I am a beginner, new to android technology. Actually I tried to solve already existing question through different approach. I took 3 fragments in single activity, and in 1st fragment i took editText, in 2nd fragment I took button and after clicking on that button I tried to display the fragment1 data in 3rd fragment By passing value through Bundle and I got stuck. How to do this task by this approach.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<FrameLayout
android:id="#+id/top"
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_weight="1"
>
</FrameLayout>
<FrameLayout
android:id="#+id/mid"
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_weight="1"
>
</FrameLayout>
<FrameLayout
android:id="#+id/bottom"
android:layout_width="match_parent"
android:layout_height="150dp"
android:layout_weight="1"
>
</FrameLayout>
</LinearLayout>
MainActivity
package com.example.com.dynamicfragmentproject;
import android.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
android.support.v4.app.FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Top_fragment frg1=new Top_fragment();
transaction.add(R.id.top,frg1);
transaction.commit();
}
public void cacheData(String str) {
android.support.v4.app.FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Mid_fragment frg2=new Mid_fragment();
transaction.add(R.id.mid,frg2);
transaction.commit();
Bundle bundle = new Bundle();
bundle.putString("editText",str);
frg2.setArguments(bundle);
}
public void cacheData1(String name) {
android.support.v4.app.FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Bottom_fragment frg3=new Bottom_fragment();
transaction.add(R.id.bottom,frg3);
transaction.commit();
Bundle bundle = new Bundle();
bundle.putString("editText",name);
frg3.setArguments(bundle);
}
}
fragment1.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Top_fragment">
<!-- TODO: Update blank fragment layout -->
<EditText
android:id="#+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="#string/hello_blank_fragment"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:textColor="#color/colorPrimary"/>
</RelativeLayout>
Fragment1.java
package com.example.com.dynamicfragmentproject;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class Top_fragment extends Fragment {
private EditText editText;
View view;
public Top_fragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.fragment_top_fragment, container, false);
editText = view.findViewById(R.id.editText1);
String str = editText.getText().toString();
MainActivity main = (MainActivity) getActivity();
main.cacheData(str);
return view;
}
}
fragment2.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Mid_fragment">
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="25dp"
android:layout_marginRight="25dp"
android:text="Submit"
android:textAllCaps="false"
android:textColor="#color/colorPrimary"
android:layout_centerVertical="true"
android:layout_centerHorizontal="false"
/>
</RelativeLayout>
Fragment2.java
package com.example.com.dynamicfragmentproject;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
public class Mid_fragment extends Fragment {
private Button buttonSubmit;
View view;
public Mid_fragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_mid_fragment, container, false);
buttonSubmit = view.findViewById(R.id.button1);
buttonSubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
MainActivity main1 = (MainActivity) getActivity();
Bundle bundle = getArguments();
String name = bundle.getString("editText");
main1.cacheData1(name);
}
});
return view;
}
}
fragment3.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/bottom"
tools:context=".Bottom_fragment">
<!-- TODO: Update blank fragment layout -->
<TextView
android:id="#+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="#color/colorPrimary"
android:padding="10dp"
/>
</FrameLayout>
Fragment3.java
package com.example.com.dynamicfragmentproject;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
public class Bottom_fragment extends Fragment {
private TextView viewText;
View view;
public Bottom_fragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.fragment_bottom_fragment, container, false);
viewText = view.findViewById(R.id.textView1);
Bundle bundle = getArguments();
String name = bundle.getString("editText");
viewText.setText(name);
return view;
}
}
In first fragment create a object of second fragment.
FragmentTwo fragmenttwo=new FragementTwo();
Bundle bundle = new Bundle();
bundle.putSerializable(object,"data")
fragmenttwo.setArguments(bundle);
In the second fragment
Bundle bundle = getArguments();
if(bundle != null){
SampleModel model = (SampleModel) bundle.getSerializable("data");
}
You need to change code in MainActivity, you commit() before set args. Change code in whole app like below
public void cacheData(String str) {
android.support.v4.app.FragmentManager manager = getSupportFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
Mid_fragment frg2=new Mid_fragment();
Bundle bundle = new Bundle();
bundle.putString("editText",str);
frg2.setArguments(bundle);
transaction.add(R.id.mid,frg2);
transaction.commit();
}
And get data on Fragment onCreateView:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
String strtext = getArguments().getString("edttext");
return inflater.inflate(R.layout.fragment, container, false);
}
You can commit a transaction using commit() only prior to the activity saving its state (when the user leaves the activity). If you attempt to commit after that point, an exception is thrown. This is because the state after the commit can be lost if the activity needs to be restored. For situations in which it's okay that you lose the commit, use commitAllowingStateLoss().
For more detail you may refer this link
Updated :
In your code pass bundle value is perfect but when you get string of editext in Mid_fragment
getArguments().getString("editText");
this getting empty that's why solution is you do not need to pass Top fragment value to Mid Fragment just edittext make static like this
change public static EditText editText
Top_fragment extends Fragment {
View view;
public static EditText editText;
}
and Mid_fragment add this
onClick(View v) {
if (Top_fragment.editText!=null)
strtext=Top_fragment.editText.getText().toString();
here is full code of Mid_fragment
public class Mid_fragment extends Fragment {
View view;
private Button buttonSubmit;
public Mid_fragment() {
// Required empty public constructor
}
String strtext="";
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_mid_fragment, container, false);
//strtext = getArguments().getString("editText");
buttonSubmit = view.findViewById(R.id.button1);
buttonSubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (Top_fragment.editText!=null)
strtext=Top_fragment.editText.getText().toString();
MainActivity main1 = (MainActivity) getActivity();
main1.cacheData1(strtext);
}
});
return view;
}
}
Related
So I'm making an app where the bottom navigation lets you click through different web pages and I've come across a problem. I can't seem to get it where the webview will function correctly inside the fragment class.
activity_main
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragment_container"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginBottom="56dp">
</FrameLayout>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/nav_view"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="0dp"
android:layout_marginEnd="0dp"
android:background="?android:attr/windowBackground"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:menu="#menu/bottom_nav_menu" />
</androidx.constraintlayout.widget.ConstraintLayout>
fragment_clever.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<WebView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/clever_web"></WebView>
</RelativeLayout>
cleverfragment.java (the one im currently working with)
package com.port.schoool;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
public class CleverFragment extends Fragment {
WebView webview;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
webview.findViewById(R.id.clever_web);
webview.getSettings().setJavaScriptEnabled(true);
webview.loadUrl("google.com");
return inflater.inflate(R.layout.fragment_clever, null);
}
}
mainactivity.java
package com.port.schoool;
import android.os.Bundle;
import android.view.MenuItem;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import com.google.android.material.bottomnavigation.BottomNavigationView;
public class MainActivity extends AppCompatActivity implements BottomNavigationView.OnNavigationItemSelectedListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
BottomNavigationView navView = findViewById(R.id.nav_view);
navView.setOnNavigationItemSelectedListener(this);
loadFragment(new ReadWorksFragment());
}
private boolean loadFragment(Fragment fragment) {
if (fragment != null) {
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragment_container, fragment)
.commit();
return true;
}
return false;
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem menuItem) {
Fragment fragment = null;
switch (menuItem.getItemId()) {
case R.id.navigation_home:
fragment = new ReadWorksFragment();
break;
case R.id.navigation_dashboard:
fragment = new CleverFragment();
break;
case R.id.navigation_notifications:
fragment = new PortalFragment();
break;
}
return loadFragment(fragment);
}
}
Here is my logcat logs for the crashes:
2019-08-04 18:05:25.164 7425-7425/com.port.schoool E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.port.schoool, PID: 7425
java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.webkit.WebView.findViewById(int)' on a null object reference
at com.port.schoool.CleverFragment.onCreateView(CleverFragment.java:20)
at androidx.fragment.app.Fragment.performCreateView(Fragment.java:2439)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1460)
at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:802)
at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625)
at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411)
at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2273)
at androidx.fragment.app.FragmentManagerImpl$1.run(FragmentManager.java:733)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6960)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:441)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1408)
Replace your fragment with:
public class CleverFragment extends Fragment {
WebView webview;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_clever, container, false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
webview = view.findViewById(R.id.clever_web);
webview.getSettings().setJavaScriptEnabled(true);
webview.loadUrl("https://google.com");
}
}
Of note:
Your original code would not compile, as there is no findViewById() on Fragment
The right version of inflate() to use in onCreateView() is the one that takes the container and false as the second and third parameters
You configure your fragment's views in onViewCreated()
You need to call findViewById() on the inflated layout (view in onViewCreated()) and assign that to webview
You need to use a valid URL with loadUrl()
This sort of stuff should be covered in your book on Android app development.
I am very new to android development. I went through several tutorials on fragments but for some reason i cant seem to add a fragment from my main view. I'm not trying to do anything painfully complicated. All I want is to create my fragments and add them to my main activity. That's it. But every time I run my application all I get is a blank screen. I debug it and it is going to the fragment. This leads me to believe that the issue may be in the xml laout file (maybe).
Here is my MainActivity.java
package com.android.myCompany.nameOfApp;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Begin the transaction
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.foo_frame_layout, new FooFragment());
ft.commit();
}
}
Here is my Fragment.cs
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
/**
* A simple {#link Fragment} subclass.
*/
public class FooFragment extends Fragment {
public FooFragment () {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
TextView textView = new TextView(getActivity());
textView.setText(R.string.hello_blank_fragment);
return textView;
}
}
Here is my layout activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:background="#drawable/background_portrait">
<FrameLayout
android:id="#+id/copyright_frame_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
</RelativeLayout>
Here is my fragment_foo.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/copyright_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".FooFragment">
<!-- TODO: Update blank fragment layout -->
<ImageView
android:id="#+id/imageView5"
android:layout_width="wrap_content"
android:layout_height="102dp"
android:layout_marginTop="16dp"
android:layout_marginBottom="8dp"
android:adjustViewBounds="false"
android:cropToPadding="false"
app:layout_constraintBottom_toTopOf="#+id/imageView6"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.504"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/logo" />
<ImageView
</RelativeLayout>
Can anyone tell me what is wrong with my set up? Many thanks in advance.
Change with this in your fragment class :
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_foo, container, false); // This line will inflate your fragment_foo layout and return it's rootview for fragment inflation
}
and then find your fragment views in onViewCreated method of fragment.
Try adding this in your fragment class...
public static FooFragment newInstance()
{
return new FooFragment();
}
#Override
public View onCreateView(#NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_layout, container, false);
// work with your ui code here.
return view;
}
And call this method in your activity...
// Begin the transaction
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.foo_frame_layout, FooFragment.newInstance());
ft.commit();
java & Two.java)
into each fragments there's editext:
One : editText_One
Two : editText_Two
How to save and resotre editText_One (and editText_Two), when i switch between fragments?
I've tried several things after reading tutos, but nothing working well ;(
One.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/tv_one"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="one" />
<EditText
android:layout_width="237dp"
android:layout_height="wrap_content"
android:inputType="date"
android:ems="10"
android:id="#+id/editText_One"
android:text="blabla"
android:layout_gravity="center_horizontal" />
</LinearLayout>
Two.xml :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/tv_one"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="TWO" />
<EditText
android:layout_width="237dp"
android:layout_height="wrap_content"
android:inputT`enter code here`ype="date"
android:ems="10"
android:id="#+id/editText_Two"
android:layout_gravity="center_horizontal" />
One.java :
/**
*
*/
package com.example.navigationsubmenu;
/**
* #author info-medios
*
*/
import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
import java.util.Calendar;
public class One extends Fragment {
// public static final String EXTRA_URL_nommatiere = "url";
EditText editText_one;
// String valeur;
private final String PERSISTENT_VARIABLE_BUNDLE_KEY = "persistentVariable";
public One() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Bundle bundle = new Bundle();
/* Bundle bundle = getActivity().getIntent().getExtras();
Bundle mySavedInstanceState = getArguments();
if (bundle!= null) {// to avoid the NullPointerException
// editText_one.setText("premiere");
String persistentVariable = mySavedInstanceState.getString(PERSISTENT_VARIABLE_BUNDLE_KEY);
editText_one.setText(persistentVariable);
}*/
Bundle extras = getActivity().getIntent().getExtras();
if (extras != null) {
String persistentVariable = extras.getString(PERSISTENT_VARIABLE_BUNDLE_KEY);
editText_one.setText(persistentVariable);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.one, container, false);
//Instancier vos composants graphique ici (faƮtes vos findViewById)
editText_one = (EditText) view.findViewById(R.id.editText_One); //getview marche aussi
/* Bundle extras = getActivity().getIntent().getExtras();
if (extras != null) {
valeur = extras.getString(EXTRA_URL_nommatiere); //Affiche le nom matiere
}
else
{
}
editText_one.setText(valeur );*/
return view;
}
#Override
public void onPause() {
super.onPause();
String persistentVariable = editText_one.getText().toString();
Intent intent = new Intent(getActivity(), One.class);
intent.putExtra(persistentVariable, PERSISTENT_VARIABLE_BUNDLE_KEY);
//startActivity(intent);
getArguments().putString(persistentVariable, PERSISTENT_VARIABLE_BUNDLE_KEY);
}
/* #Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
Bundle extras = getActivity().getIntent().getExtras();
if (savedInstanceState != null) {
// Restore last state for checked position.
valeur = extras.getString(EXTRA_URL_nommatiere);
}
}
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
savedInstanceState.putString("TEXT", valeur);
}*/
/* #Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
Log.v(TAG, "Inside of onRestoreInstanceState");
valeur = extras.getString(EXTRA_URL_nommatiere);
}*/
}
Can someone can help me please,
many thnaks
First you need to attach the fragments to activity then you can simply define two strings String one ,String two in the activity containing the fragments and assign the value of each editText to diffrent one
i.e
String one=editTextOne.getText.toString();
String two=editTextTwo.getText.toString();
When you have to switch between either activities or fragments, you can use Shared Preferences to store a small amount of datas and retrieve them.
Shared Prefs are small sets of key/value pairs.
Write
SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.();
editor.putInt(getString(R.string.saved_high_score), newHighScore);
editor.commit();
Read
SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
int defaultValue = getResources().getInteger(R.string.saved_high_score_default);
long highScore = sharedPref.getInt(getString(R.string.saved_high_score), defaultValue);
You can write and read any primitive data types such as Strings using put[Type] and get[Type] methods.
Source codes above come from the official android developer training and belongs to Android.
"is there a way with saveInstanceState ?"
I think this bundle is usefull when one activity is destroyed and created by Screen rotation or resumed after a call, but not when switching between activities and fragments.
But you can try it. I know that views like EditText with id have a built-in saveInstanceState so you do not have to handle it manually.
To switch between fragments you can use activity class scoped properties. You will need to add interfaces to your fragments to allow them to communicate with the activity.
EXAMPLE
The following example shows how to switch between fragments and keep EditText values.
The MainActivity contains a FrameLayout and two buttons. The fragment transaction is done on button click events.
Fragments include an interface to communicate with the activity. Each time the EditText value is changed, the activity's property is updated.
The activity communicates with the fragment to set EditText value right after the transaction.
First of all, here are xml layouts files for the MainActivity, the FragmentA and the FragmentB classes :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="100"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="morbak.stackoverflow.fragmentcommunication.MainActivity">
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="50"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="50"
android:orientation="horizontal"
android:weightSum="100">
<Button
android:id="#+id/button1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="50"
android:text="Fragment A" />
<Button
android:id="#+id/button2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="50"
android:text="Fragment B" />
</LinearLayout>
</LinearLayout>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:id="#+id/etOne"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Fragment A content"/>
</LinearLayout>
fragment_a.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:id="#+id/etTwo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Fragment B content"/>
</LinearLayout>
fragment_b.xml
Then, here are Fragments A and B classes. Source code is self explanatory.
package morbak.stackoverflow.fragmentcommunication;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class FragmentA extends Fragment {
//Views
EditText etOne;
//Fields
String value;
//Listeners
OnFragmentASelectedListener mCallback;
//Context
Context context;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
//Inflate views and layouts
View rootView = inflater.inflate(R.layout.fragment_a, container, false);
etOne = (EditText) rootView.findViewById(R.id.etOne);
//Events
etOne.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
//Execute the interface's abstract method
mCallback.onFragmentASelected(s.toString());
}
#Override
public void afterTextChanged(Editable s) {
}
});
etOne.setText(value);
return rootView;
}
//Set the fragment's field value
public void setEditText(String newValue) {
value = newValue;
}
//Interface
public interface OnFragmentASelectedListener {
public void onFragmentASelected(String value);
}
//Throws an exception if the activity implements FragmentA.OnFragmentASelectedListener, but not the abstract method
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
context = activity;
// This makes sure that the container activity has implemented
// the callback interface. If not, it throws an exception
try {
mCallback = (OnFragmentASelectedListener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement OnFragmentASelectedListener");
}
}
}
FragmentA.java
The same work should be done with FragmentB, but you obviously have to search and replace FragmentA to FragmentB and etOne to etTwo.
Finally, here is the MainActivity who handles fragment transactions and uses fragments' listeners :
package morbak.stackoverflow.fragmentcommunication;
import android.content.Context;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements FragmentA.OnFragmentASelectedListener, FragmentB.OnFragmentBSelectedListener {
Button button1;
Button button2;
FragmentTransaction transaction;
FragmentA fragmentA;
FragmentB fragmentB;
String editTextOne;
String editTextTwo;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1 = (Button) findViewById(R.id.button1);
button2 = (Button) findViewById(R.id.button2);
editTextOne = "";
editTextTwo = "";
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
transaction = getSupportFragmentManager().beginTransaction();
fragmentA = new FragmentA();
transaction.replace(R.id.fragment_container, fragmentA);
transaction.addToBackStack(null);
transaction.commit();
fragmentA.setEditText(editTextOne);
}
});
button2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
transaction = getSupportFragmentManager().beginTransaction();
fragmentB = new FragmentB();
transaction.replace(R.id.fragment_container, fragmentB);
transaction.addToBackStack(null);
transaction.commit();
fragmentB.setEditText(editTextTwo);
}
});
}
public void onFragmentASelected(String value) {
editTextOne = value;
}
public void onFragmentBSelected(String value) {
editTextTwo = value;
}
}
MainActivity.java
How can I add fragments for each tab in BottomBar in Android studio please a good example like list view or grid view for each tab..thanks
You need to implement SetOnTabSelectListerner.
bottomBar.setOnTabSelectListener(new OnTabSelectListener() {
#Override
public void onTabSelected(#IdRes int tabId) {
Fragment fragment = null;
Class fragmentClass = null;
switch (tabId) {
case R.id.tab_one:
fragmentClass = TabOneFragment.class;
break;
case R.id.tab_two:
fragmentClass = TabTwoFragment.class;
break;
case R.id.tab_three:
fragmentClass = TabThreeFragment.class;
break;
case R.id.tab_four:
fragmentClass = TabFourFragment.class;
break;
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
}
});
main_activity.java
import android.app.Activity;
import android.app.FragmentManager;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
public class MainActivity extends FragmentActivity implements communicator{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public void respond(int i) {
android.support.v4.app.FragmentManager fm=getSupportFragmentManager();
FragmentB f2= (FragmentB)fm.findFragmentById(R.id.fragment2);
f2.changedata(i);
}
}
main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<android.widget.LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#00BBFF"
android:orientation="vertical"
tools:context="com.example.dhanya.myfragmentexample.MainActivity">
<fragment
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/fragment"
android:name="com.example.dhanya.myfragmentexample.FragmentA"
/>
<fragment
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragment2"
android:name="com.example.dhanya.myfragmentexample.FragmentB"
/>
</android.widget.LinearLayout>
fragmentA.java
package com.example.dhanya.myfragmentexample;
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
public class FragmentA extends Fragment implements AdapterView.OnItemClickListener{
ListView list;
communicator comm;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
comm= (communicator) getActivity();
list=(ListView)getActivity().findViewById(R.id.lv);
ArrayAdapter ad=ArrayAdapter.createFromResource(getActivity(),R.array.listval,android.R.layout.simple_list_item_1);
list.setAdapter(ad);
list.setOnItemClickListener(this);
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
TextView txt=(TextView)view;
String str=txt.getText().toString();
comm.respond(position);
}
}
fragmentA.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.dhanya.myfragmentexample.FragmentA"
android:background="#FFBB00">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/lv"/>
</FrameLayout>
fragmentB.java
package com.example.dhanya.myfragmentexample;
import android.content.Context;
import android.content.res.Resources;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class FragmentB extends Fragment {
TextView txt;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_fragment_b, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
txt=(TextView)getActivity().findViewById(R.id.textv);
}
public void changedata(int i)
{
Resources res=getResources();
String[] des=res.getStringArray(R.array.desciptions);
// String str=Integer.toString(i);
txt.setText(des[i]);
// txt.setText(str); }}
fragmentB.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.dhanya.myfragmentexample.FragmentB"
android:background="#99CC00"
>
<!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/textv"/>
</FrameLayout>
strings.xml
<resources>
<string name="app_name">MyFragmentExample</string>
<!-- TODO: Remove or change this placeholder text -->
<string name="hello_blank_fragment">Hello blank fragment</string>
<string-array name="listval">
<item>fragments</item>
<item>Activities</item>
<item>Services</item>
<item>Content Providers</item>
</string-array>
<string-array name="desciptions">
<item>A Fragment represents a behavior or a portion of user interface in an Activity. You can combine multiple fragments in a single activity to build a multi-pane UI and reuse a fragment in multiple activities. You can think of a fragment as a modular section of an activity, which has its own lifecycle, receives its own input events, and which you can add or remove while the activity is running (sort of like a "sub activity" that you can reuse in different activities).</item>
<item>Activities are one of the fundamental building blocks of apps on the Android platform. They serve as the entry point for a user's interaction with an app, and are also central to how a user navigates within an app (as with the Back button) or between apps (as with the Recents button). </item>
<item>A Service is an application component that can perform long-running operations in the background, and it does not provide a user interface. Another application component can start a service, and it continues to run in the background even if the user switches to another application. Additionally, a component can bind to a service to interact with it and even perform interprocess communication (IPC). For example, a service can handle network transactions, play music, perform file I/O, or interact with a content provider, all from the background.</item>
<item>Content providers can help an application manage access to data stored by itself, stored by other apps, and provide a way to share data with other apps. They encapsulate the data, and provide mechanisms for defining data security. Content providers are the standard interface that connects data in one process with code running in another process. Implementing a content provider has many advantages. </item>
</string-array>
</resources>
communicator.java
public interface communicator {
public void respond(int i);
}
//Grid view
main_activity.xml
<ScrollView xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<GridView
android:id="#+id/gridview1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:columnWidth="50dp"
android:gravity="center"
android:numColumns="auto_fit"
android:stretchMode="columnWidth" >
</GridView>
</RelativeLayout>
</ScrollView>
mainactivity.java
package com.example.harish.mylayoutexamples;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.GridView;
import android.widget.TextView;
import android.widget.Toast;
public class GridActivity extends AppCompatActivity implements AdapterView.OnItemClickListener{
GridView gridView;
static final String[] numbers = new String[] {
"A", "B", "C", "D", "E",
"F", "G", "H", "I", "J",
"K", "L", "M", "N", "O",
"P", "Q", "R", "S", "T",
"U", "V", "W", "X", "Y", "Z"
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_grid);
gridView = (GridView) findViewById(R.id.gridview1);
// Create adapter to set value for grid view
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, numbers);
gridView.setAdapter(adapter);
gridView.setOnItemClickListener(this);
/* gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
Toast.makeText(getApplicationContext(),
((TextView) v).getText() , Toast.LENGTH_SHORT).show();
}
});*/
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getApplicationContext(),
((TextView) view).getText() , Toast.LENGTH_SHORT).show();
}
}
fragments dynamic loading
Main activity. Java
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
Button firstFragment, secondFragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// get the reference of Button's
firstFragment = (Button) findViewById(R.id.firstFragment);
secondFragment = (Button) findViewById(R.id.secondFragment);
// perform setOnClickListener event on First Button
firstFragment.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// load First Fragment
loadFragment(new FirstFragment());
}
});
// perform setOnClickListener event on Second Button
secondFragment.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// load Second Fragment
loadFragment(new SecondFragment());
}
});
}
private void loadFragment(Fragment fragment) {
// create a FragmentManager
FragmentManager fm = getFragmentManager();
// android.support.v4.app.FragmentManager fm=getSupportFragmentManager();
// create a FragmentTransaction to begin the transaction and replace the Fragment
FragmentTransaction fragmentTransaction = fm.beginTransaction();
// replace the FrameLayout with new Fragment
fragmentTransaction.replace(R.id.frameLayout, fragment);
//fragmentTransaction.add(R.id.firstFragment,fragment);
fragmentTransaction.commit(); // save the changes
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
MAIN_ACTIVTY.XML
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity">
<!-- display two Button's and a FrameLayout to replace the Fragment's -->
<Button
android:id="#+id/firstFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/button_background_color"
android:text="First Fragment"
android:textColor="#color/white"
android:textSize="20sp" />
<Button
android:id="#+id/secondFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:background="#color/button_background_color"
android:text="Second Fragment"
android:textColor="#color/white"
android:textSize="20sp" />
<FrameLayout
android:id="#+id/frameLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="10dp" />
</LinearLayout>
FIRST_FRAGMENT.JAVA
package com.abhiandroid.fragmentexample;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class FirstFragment extends Fragment {
View view;
Button firstButton;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.fragment_first, container, false);
// get the reference of Button
firstButton = (Button) view.findViewById(R.id.firstButton);
// perform setOnClickListener on first Button
firstButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// display a message by using a Toast
Toast.makeText(getActivity(), "First Fragment", Toast.LENGTH_LONG).show();
}
});
return view;
}
}
FIRST_FRAGMENT>XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.abhiandroid.fragmentexample.FirstFragment">
<!--TextView and Button displayed in First Fragment -->
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="100dp"
android:text="This is First Fragment"
android:textColor="#color/black"
android:textSize="25sp" />
<Button
android:id="#+id/firstButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:background="#color/green"
android:text="First Fragment"
android:textColor="#color/white"
android:textSize="20sp"
android:textStyle="bold" />
</RelativeLayout>
SECOND_FRAGMENT>JAVA
package com.abhiandroid.fragmentexample;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class SecondFragment extends Fragment {
View view;
Button secondButton;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
view = inflater.inflate(R.layout.fragment_second, container, false);
// get the reference of Button
secondButton = (Button) view.findViewById(R.id.secondButton);
// perform setOnClickListener on second Button
secondButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// display a message by using a Toast
Toast.makeText(getActivity(), "Second Fragment", Toast.LENGTH_LONG).show();
}
});
return view;
}
}
SECOND_FRAGMENT>XML
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.abhiandroid.fragmentexample.SecondFragment">
<!--TextView and Button displayed in Second Fragment -->
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="100dp"
android:text="This is Second Fragment"
android:textColor="#color/black"
android:textSize="25sp" />
<Button
android:id="#+id/secondButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:background="#color/green"
android:text="Second Fragment"
android:textColor="#color/white"
android:textSize="20sp"
android:textStyle="bold" />
</RelativeLayout>
main_activity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class MainActivity extends AppCompatActivity implements communicator {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public void respond(String i) {
android.support.v4.app.FragmentManager fm=getSupportFragmentManager();
FragmentB f2= (FragmentB)fm.findFragmentById(R.id.fragment2);
f2.changedata(i);
}
}
main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<android.widget.LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.dhanya.myfragmentcommsimple.MainActivity"
android:orientation="vertical">
<fragment
android:layout_width="match_parent"
android:layout_height="250dp"
android:id="#+id/fragment"
android:name="com.example.dhanya.myfragmentcommsimple.FragmentA">
</fragment>
<fragment
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragment2"
android:name="com.example.dhanya.myfragmentcommsimple.FragmentB">
</fragment>
</android.widget.LinearLayout>
fragment_A.java
package com.example.dhanya.myfragmentcommsimple;
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ListView;
public class FragmentA extends Fragment implements View.OnClickListener{
int count=0;
Button bt;
communicator comm;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
comm= (communicator) getActivity();
bt=(Button)getActivity().findViewById(R.id.btn);
bt.setOnClickListener(this);
}
#Override
public void onClick(View v) {
count++;
comm.respond("The button is clicked "+ count+" times");
}
}
FRAGMET_A.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.dhanya.myfragmentcommsimple.FragmentA"
android:background="#99FF00">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/btn"
android:text="counter"
android:layout_margin="40dp"/>
</FrameLayout>
FRAGMENT_B.java
package com.example.dhanya.myfragmentcommsimple;
import android.content.Context;
import android.content.res.Resources;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class FragmentB extends Fragment {
TextView txt;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_fragment_b, container, false);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
txt=(TextView)getActivity().findViewById(R.id.tv);
}
public void changedata(String i)
{
txt.setText(i);
}
}
FRAGMENT_B.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.dhanya.myfragmentcommsimple.FragmentB"
android:background="#FFBB00">
<!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="haiiii"
android:id="#+id/tv"
android:layout_margin="50dp"/>
</FrameLayout>
COMMUNICATOR.java
package com.example.dhanya.myfragmentcommsimple;
public interface communicator {
public void respond(String i);
}
I am working on fragments
Use case i am trying to implement::
I am using dynamic fragments
I am using three fragments in a single activity
my goal is to communicate between all the three fragments
I am using support package for fragments
Each fragment has a single widget
my_fragment1 has edittext
my_fragment2 has button
my_fragment3 has TextView
On click of button the text from the edittext must be displayed in the textview
What i have tried so far i have constructed most of the scenario below
Top_Fragment.java
public class Top_Fragment extends Fragment{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view=inflater.inflate(R.layout.my_fragment1, container, false);
return view;
}
}
Middle_Fragment.java
package com.example.deleteme;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
public class Middle_Fragment extends Fragment{
View view;
Button btn;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
view=inflater.inflate(R.layout.my_fragment2, container, false);
btn=(Button) view.findViewById(R.id.button1);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
});
return view;
}
}
Bottom_Fragment.java
public class Bottom_Fragment extends Fragment{
View view;
TextView display_text;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
view=inflater.inflate(R.layout.my_fragment3, container,false);
display_text=(TextView) view.findViewById(R.id.editText1);
return view;
}
public void setName(String Name){
display_text.setText("Result::" + Name);
}
}
MainActivity.java
public class MainActivity extends FragmentActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Top_Fragment frg=new Top_Fragment();//create the fragment instance for the top fragment
Middle_Fragment frg1=new Middle_Fragment();//create the fragment instance for the middle fragment
Bottom_Fragment frg2=new Bottom_Fragment();//create the fragment instance for the bottom fragment
FragmentManager manager=getSupportFragmentManager();//create an instance of fragment manager
FragmentTransaction transaction=manager.beginTransaction();//create an instance of Fragment-transaction
transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
transaction.add(R.id.My_Container_2_ID, frg1, "Frag_Middle_tag");
transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");
transaction.commit();
}
}
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
tools:context=".MainActivity"
android:background="#color/black">
<FrameLayout
android:id="#+id/My_Container_1_ID"
android:layout_width="fill_parent"
android:layout_height="150dp"
android:background="#color/yellow">
</FrameLayout>
<FrameLayout
android:id="#+id/My_Container_2_ID"
android:layout_width="fill_parent"
android:layout_height="150dp"
android:layout_alignParentLeft="true"
android:layout_below="#+id/My_Container_1_ID"
android:background="#color/Orange" >
</FrameLayout>
<FrameLayout
android:id="#+id/My_Container_3_ID"
android:layout_width="fill_parent"
android:layout_height="150dp"
android:layout_alignParentLeft="true"
android:layout_below="#+id/My_Container_2_ID"
android:background="#color/purple" >
</FrameLayout>
</RelativeLayout>
my_fragment1.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/green" >
<EditText
android:id="#+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:ems="10"
android:textColor="#000000"
android:singleLine="true" >
<requestFocus />
</EditText>
</RelativeLayout>
my_fragment2.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#color/pink">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:background="#color/black"
android:text="Button"
android:textColor="#FFFFFF" />
</RelativeLayout>
my_fragment3.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="TextView"
android:textColor="#000000"
android:textSize="30dp" />
</RelativeLayout>
My output is Like below ::
What I am having problem in achieving ::
I am not able to set the value obtained from edit text to
textview on click of the button
Any Ideas?
All Fragment-to-Fragment communication is done through the associated Activity. Two Fragments should never communicate directly.
http://developer.android.com/training/basics/fragments/communicating.html
test.java // in your case its MainActivity
public class test extends FragmentActivity implements textEntered {
String value;
boolean check = false;
BottomFragment frg2;
FragmentTransaction transaction;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Top_Fragment frg = new Top_Fragment();
frg2 = new BottomFragment();
FragmentManager manager = getSupportFragmentManager();
transaction = manager.beginTransaction();
transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");
transaction.commit();
}
#Override
public void setValue(String editextvalue) {
value = editextvalue;
if (frg2 != null) {
frg2.setName(value);
} else {
Toast.makeText(getApplicationContext(), "fragment 2 is null", 1000).show();
}
}
}
Top_Fragment.java
public class Top_Fragment extends Fragment {
textEntered mCallback;
Button b;
EditText ed;
public interface textEntered {
public void setValue(String editextvalue);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.my_fragment1, container, false);
ed = (EditText) view.findViewById(R.id.editText1);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
b = (Button) getView().findViewById(R.id.button1);
b.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
String s = ed.getText().toString();
mCallback.setValue(s);
}
});
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// This makes sure that the container activity has implemented
// the callback interface. If not, it throws an exception
try {
mCallback = (textEntered) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString() +
" must implement textEntered");
}
}
}
my_fragment1.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<EditText
android:id="#+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:ems="10"
android:textColor="#000000"
android:singleLine="true" >
<requestFocus />
</EditText>
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/editText1"
android:layout_centerHorizontal="true"
android:layout_marginTop="20dp"
android:text="Button" />
</RelativeLayout>
Change to
display_text=(TextView) view.findViewById(R.id.textView1);
// id is textView 1 not editText1
in BottomFragment
snap
Communication between Fragments
There can be many scenarios where communication between fragment is required. You need to pass data between fragments on button click event. You may also use Android toolbar to switch between fragments. When you add buttons to your toolbar, you need to dynamically change screen using fragment.
Create an interface which will help us to communicate
Communicate.java
package com.example.amaanmemon.testfragment;
interface Communicate {
public void sendData();
}
TopFragment.java
package com.example.amaanmemon.testfragment;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class TopFragment extends Fragment {
EditText firstName;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view=inflater.inflate(R.layout.my_fragment1, container, false);
return view;
}
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
firstName = (EditText) getActivity().findViewById(R.id.editText1);
}
public String getData(){
return firstName.getText().toString();
}
}
MiddleFragment.java
package com.example.amaanmemon.testfragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
public class MiddleFragment extends Fragment implements OnClickListener{
View view;
Button btn;
Communicate cm;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
view=inflater.inflate(R.layout.my_fragment2, container, false);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
cm = (Communicate) getActivity();
btn = (Button) getActivity().findViewById(R.id.button1);
btn.setOnClickListener(this);
}
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
cm.sendData();
}
}
BottomFragment.java
package com.example.amaanmemon.testfragment;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
public class BottomFragment extends Fragment{
int count;
View view;
TextView display_text;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
view=inflater.inflate(R.layout.my_fragment3, container,false);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
display_text = (TextView)getActivity().findViewById(R.id.textView1);
}
public void incrementData(String displayText){
display_text.setText(displayText);
}
}
MainActivity.java
package com.example.amaanmemon.testfragment;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
public class MainActivity extends FragmentActivity implements Communicate{
TopFragment frg;
MiddleFragment frg1;
BottomFragment frg2;
FragmentTransaction transaction;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
frg = new TopFragment();
frg1 = new MiddleFragment();
frg2 = new BottomFragment();
FragmentManager manager=getSupportFragmentManager();
transaction=manager.beginTransaction();
transaction.add(R.id.My_Container_1_ID, frg, "Frag_Top_tag");
transaction.add(R.id.My_Container_2_ID, frg1, "Frag_Middle_tag");
transaction.add(R.id.My_Container_3_ID, frg2, "Frag_Bottom_tag");
transaction.commit();
}
#Override
public void sendData() {
String temp = frg.getData();
frg2.incrementData(temp);
}
}
You can copy xml files from question.
you can watch the output below.
You can use the Activity for that.
in the onClick of the bottom fragment you can do something like
((MainActivity) getActivity()).doIt();
And make a method doIt in your MainActivity maybe something like this
public void doIt(){
frg2.setName(frg.getText())
}
and in the top fragment make a method getText that returns the text of the EditText