Develop Reference

How to get next activity when clicked from frag button

Hi i am trying to get my NextActivity when i press on Fab in my View 1
View 1 xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/Fbutton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="300dp"
android:layout_marginLeft="180dp"
android:clickable="true"
android:paddingRight="16dp"
android:paddingBottom="16dp"
/>
</RelativeLayout>,
View.java
package com.example.myapplication;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
public class View1 extends Fragment {
private FloatingActionButton mFab;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.view1, container, false);
mFab.findViewById(R.id.Fbutton);
mFab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(getActivity(),NextActivity.class);
startActivity(intent);
}
});
return view;
}
}
Error
java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View com.google.android.material.floatingactionbutton.FloatingActionButton.findViewById(int)' on a null object reference
at com.example.myapplication.View1.onCreateView(View1.java:21)
i have tried
getContext()
View1.this
nothing worked

You haven't complete the floating button assigning.
Remove mFab.findViewById(R.id.Fbutton); this line.
Add
mFab = view.findViewById(R.id.Fbutton);
Here view is used to get the ID from the layout.

From the code that you posted most probably the problem is that you are not assigning the return value of findViewById(R.id.Fbutton); to the mFab.
mFab = findViewById(R.id.Fbutton);

Passing values among fragments through bundle

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;
}
}

How to display two fragments at the same time using TabLayout?

I use Android Tab Example with two tabs, view pager and fragments (structure on the image):
For get fragments i use the solution from this post.
When my device is rotation i want to display two fragments at the same time.
I the stackoverflow.com/questions/17970021 a similar problem, but I don't know how to apply the solution to my task, because i have TabLayout.
If you know idea, can you help me?

In activity_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="16dp"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingTop="16dp"
>
<FrameLayout
android:id="#+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
</FrameLayout>
</FrameLayout>
In MainActivity.java
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.annotation.NonNull;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
replaceFragment(0);
}
public void replaceFragment(int position) {
Fragment fragment = null;
switch (position) {
case 0:
fragment = new TabOneFragment();
break;
case 1:
fragment = new TabTwoFragment();
break;
default:
break;
}
if (null != fragment) {
FragmentManager fragmentManager = MainActivity.this.getSupportFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.replace(R.id.main_content, fragment);
transaction.addToBackStack(null);
transaction.commit();
}
}
}
in TabOneFragment.java
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
public class TabOneFragment extends Fragment {
private View inflatedView = null;
public TabOneFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
this.inflatedView = inflater.inflate(R.layout.fragment_tab_one, container, false);
return this.inflatedView;
}
}
in TabTwoFragment.java
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
public class TabTwoFragment extends Fragment {
private View inflatedView = null;
public TabTwoFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
this.inflatedView = inflater.inflate(R.layout.fragment_tab_two, container, false);
return this.inflatedView;
}
}

Error inflating class fragment, inflateexception

I am having error something its written like android view inflate exception error in inflating class fragment and its pointing to MainActivity.java class , I am trying to find but still no luck, as there is no error in android studio but error shows when running in virtual device.
activity_main.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"
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="com.example.ai_agamcompaq.flexible.MainActivity">
<fragment
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:name="com.example.ai_agamcompaq.flexible.FragmentA"
android:id="#+id/fragment"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="26dp" />
<fragment
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:name="com.example.ai_agamcompaq.flexible.FragmentB"
android:id="#+id/fragment2"
android:layout_below="#+id/fragment"
android:layout_alignStart="#+id/fragment"
android:layout_marginTop="39dp" />
</RelativeLayout>
MainActivity.java
import android.app.FragmentManager;
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(int i) {
FragmentManager manager=getFragmentManager();
FragmentB f2= (FragmentB) manager.findFragmentById(R.id.fragment2);
f2.changedata(i);
}
}
FragmentA.java
import android.app.Fragment;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class FragmentA extends Fragment implements
AdapterView.OnItemClickListener {
ListView list;
Communicator communicator;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return super.onCreateView(inflater, container, savedInstanceState);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
communicator=(Communicator)getActivity();
list= (ListView) getActivity().findViewById(R.id.listView);
ArrayAdapter adapter=ArrayAdapter.createFromResource(getActivity(),R.array.titles,android.R.layout.simple_list_item_1);
list.setAdapter(adapter);
list.setOnItemClickListener(this);
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int i, long id) {
communicator.respond(i);
}
FragmentB.java
import android.app.Fragment;
import android.content.res.Resources;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.TextView;
public class FragmentB extends Fragment {
TextView text;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.fragment_b,container,false);
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
text=(TextView) getActivity().findViewById(R.id.textView);
}
public void changedata(int i){
Resources res=getResources();
String[] description=res.getStringArray(R.array.description);
text.setText(description[i]);
}
}
Communicator.java
public interface Communicator {
public void respond(int i);
}
fragment_b.xml
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:id="#+id/editText" />
</LinearLayout>
fragment_a.xml
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true"
android:layout_alignParentLeft="true"
android:id="#+id/listView" />
strings.xml
<resources>
<string name="app_name">flexible</string>
<string-array name="titles">
<item>one</item>
<item>two</item>
<item>three</item>
<item>four</item>
</string-array>
<string-array name="description">
<item>oneoneoneoneoneoneoneoneoneoneo</item>
<item>twotwotwotwotwotwotwotwotwotwo</item>
<item>threethreethreethreethreethreethr</item>
<item>fourfourfourfourfourfourfourfourfo</item>
</string-array>
</resources>
I am having error something its written like android view inflate exception error in inflating class fragment and its pointing to MainActivity.java class , I am trying to find but still no luck, as there is no error in android studio but error shows when running in virtual device.

try this way. bind your control inside oncreatview method for fragment A
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.change_pass_frag, container);
regmail=(EditText)view.findViewById(R.id.regemail);
oldpass=(EditText)view.findViewById(R.id.oldpass);
return view;
}

i got it , i have to inflate fragment_a
View view=inflater.inflate(R.layout.fragment_a,container,false);

BottomBar fragments in Android studio

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);
}