So, i was following the NewBoston series on Android tutorials. So, there is this tutorial on setting up tabs using Tabhost and Tabspecs. Now, i tried exactly what the tutorial does but crashes and it points to a particular line in my code which is setContentView() method in the OnCreate(). I tried even removing it and ran the code but the program just crashes. What could be my mistake? I also tried the code in the following article to see if that works but it still crashes.
http://www.learn-android-easily.com/2013/07/android-tabwidget-example.html
This is my code-
Splash.java is the class that starts up the Launcher activity
public class Splash extends TabActivity {
TabHost th;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
th = (TabHost)findViewById(R.id.tabHost2);
TabHost.TabSpec tab1 = th.newTabSpec("First Tab");
TabHost.TabSpec tab2 = th.newTabSpec("Second Tab");
TabHost.TabSpec tab3 = th.newTabSpec("Third tab");
tab1.setIndicator("Tab1");
tab1.setContent(new Intent(this,TabActivity1.class));
tab2.setIndicator("Tab2");
tab2.setContent(new Intent(this, TabActivity2.class));
tab3.setIndicator("Tab3");
tab3.setContent(new Intent(this, TabActivity3.class));
th.addTab(tab1);
th.addTab(tab2);
th.addTab(tab3);
}
}
TabActivity1.java-
public class TabActivity1 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView tv=new TextView(this);
tv.setTextSize(25);
tv.setGravity(Gravity.CENTER_VERTICAL);
tv.setText("This Is Tab1 Activity");
setContentView(tv);
}
}
TabActivity2.java:-
public class TabActivity2 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView tv=new TextView(this);
tv.setTextSize(25);
tv.setGravity(Gravity.CENTER_VERTICAL);
tv.setText("This Is Tab2 Activity");
setContentView(tv);
}
}
TabActivity3.java
public class TabActivity3 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
TextView tv=new TextView(this);
tv.setTextSize(25);
tv.setGravity(Gravity.CENTER_VERTICAL);
tv.setText("This Is Tab3 Activity");
setContentView(tv);
}
}
splash.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">
<TabHost
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/tabHost2"
android:layout_gravity="center_horizontal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TabWidget
android:id="#android:id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"></TabWidget>
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"></LinearLayout>
<LinearLayout
android:id="#+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"></LinearLayout>
<LinearLayout
android:id="#+id/linearLayout3"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"></LinearLayout>
</FrameLayout>
</LinearLayout>
</TabHost>
</LinearLayout>
Change this line
th = (TabHost)findViewById(R.id.tabHost2);
to
th = (TabHost)findViewById(android.R.id.tabHost2);
This will do.
Because, in the layout file, you might have set Tabhost id like this android:id="#android:id/tabhost2">
Related
I'm tying to setup the toolbar in the activity, but the when i set a title and the default back button. it doesn't show anything
public class LaptopDetail extends AppCompatActivity {
Toolbar toolbar;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_laptop_detail);
setupToolbar();
}
void setupToolbar() {
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
Intent data = getIntent();
getSupportActionBar().setTitle(data.getStringExtra("laptop_name"));
getSupportActionBar().setDisplayShowHomeEnabled(true);
}
public boolean onOptionsItemSelected(MenuItem item){
Intent myIntent = new Intent(getApplicationContext(), BrandOffers.class);
startActivityForResult(myIntent, 0);
return true;
}
}
and here is my xml
<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="com.example.ahmed.myapplication3.LaptopDetail">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#273243"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" >
</android.support.v7.widget.Toolbar>
</RelativeLayout>
</RelativeLayout>
is there anything missing in my code, by the way, I'm using the same code in different activity and it is working
thanks in advance
You haven't included the content of your theme style, but I think that's where the problem might be. Check out this answer, I hope it helps.
Mainactivity:
public class MainActivity extends AppCompatActivity {
TabHost mTabHost;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTabHost = (TabHost) findViewById(android.R.id.tabhost);
setupTab(new TextView(this), "Tab 1");
setupTab(new TextView(this), "Tab 2");
setupTab(new TextView(this), "Tab 3");
}
private void setupTab(final View view, final String tag) {
View tabview = createTabView(mTabHost.getContext(), tag);
TabHost.TabSpec setContent = mTabHost.newTabSpec(tag).setIndicator(tabview).setContent(new TabHost.TabContentFactory() {
public View createTabContent(String tag) {return view;}
});
mTabHost.addTab(setContent);
}
private static View createTabView(final Context context, final String text) {
View view = LayoutInflater.from(context).inflate(R.layout.tabs_bg, null);
TextView tv = (TextView) view.findViewById(R.id.tabsText);
tv.setText(text);
return view;
}
}
Activity_main
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TabWidget android:id="#android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<FrameLayout android:id="#android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
</FrameLayout>
</LinearLayout>
</TabHost>
I am experimenting with tabs in order to make a bottom navigation bar without material design library.
How to fix this error? (Attempt to invoke virtual method 'void android.widget.TabWidget.setStripEnabled(boolean)' on a null object reference)
You need invoke mTabHost.setup(...);
The reason is your activity does not extends TabActivity, you should invoke TabHost.setup(...) before TabHost.addTab(...) method.
I encountered a problem that I didn't managed to solve: I have a MainActivity where there's a NavigationDrawer that allows me to go to three different activities. Those extend the MainActivity so I get the Drawer in every activity.
In the same MainActivity, I put a TabLayout with three tab Fragments.
The problem I'm facing is that whenever I go to one of the three activity from the drawer layout, I don't get the layout xml attached to Activity1 but instead I get again the TabLayout with the Fragments.
How can I solve this?
The result should look like Google Play app.
Here's my MainActivity:
public class MainActivity extends AppCompatActivity {
DrawerLayout mDrawerLayout;
ListView mDrawerList;
ActionBarDrawerToggle mDrawerToggle;
CollectionPagerAdapter mCollectionPagerAdapter;
ViewPager mViewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar_layout);
TextView mTitle = (TextView) toolbar.findViewById(R.id.toolbar_title);
mTitle.setText(R.string.app_name);
setSupportActionBar(toolbar);
assert getSupportActionBar() != null;
this.getSupportActionBar().setDisplayShowTitleEnabled(false);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer);
Button button1 = (Button)findViewById(R.id.button1); //this is inside the drawer layout
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, Activity1.class);
startActivity(intent);
}
});
mDrawerToggle = new ActionBarDrawerToggle(this,
mDrawerLayout,
null,
R.string.drawer_open,
R.string.drawer_close) {
public void onDrawerClosed(View v) {
super.onDrawerClosed(v);
invalidateOptionsMenu();
syncState();
}
public void onDrawerOpened(View v) {
super.onDrawerOpened(v);
invalidateOptionsMenu();
syncState();
}
};
mDrawerLayout.addDrawerListener(mDrawerToggle);
mDrawerToggle.setDrawerIndicatorEnabled(false);
mDrawerToggle.syncState();
mCollectionPagerAdapter = new CollectionPagerAdapter(
getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mCollectionPagerAdapter);
TabLayout tabs = (TabLayout)findViewById(R.id.tabs);
tabs.setupWithViewPager(mViewPager);
}
public class CollectionPagerAdapter extends FragmentPagerAdapter {
//final int NUM_ITEMS = 3; // number of tabs
public CollectionPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position)
{
switch (position) {
case 0:
return new Tab1();
case 1:
return new Tab2();
case 2:
return new Tab3();
}
return null;
}
#Override
public int getCount()
{
return 3;
}
#Override
public CharSequence getPageTitle(int position) {
switch (position)
{
case 0:
return getString(R.string.tab1);
case 1:
return getString(R.string.tab2);
case 2:
return getString(R.string.tab3);
}
return null;
}
}
#Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
mDrawerToggle.syncState();
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home: {
if (mDrawerLayout.isDrawerOpen(mDrawerList)) {
mDrawerLayout.closeDrawer(mDrawerList);
} else {
mDrawerLayout.openDrawer(mDrawerList);
}
return true;
}
default:
return super.onOptionsItemSelected(item);
}
}
Activity1:
public class Activity1 extends MainActivity { //extends MainActivity
#Override
protected void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.classe1); //setContentView before super.onCreate(savedInstanceState) allows me to get drawer in each activity
super.onCreate(savedInstanceState);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar_layout);
TextView mTitle = (TextView) toolbar.findViewById(R.id.toolbar_title);
mTitle.setText("Activity 1");
setSupportActionBar(toolbar);
assert getSupportActionBar() != null;
this.getSupportActionBar().setDisplayShowTitleEnabled(false);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
}
Tab1 (Fragment):
public class Tab1 extends Fragment {
View view;
public Tab1() {
}
#SuppressLint("InflateParams")
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.tab1, null);
return view;
}
and my activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:layout_height="match_parent"
android:layout_width="match_parent">
<android.support.v4.view.ViewPager
android:layout_height="match_parent"
android:layout_width="match_parent"
android:layout_marginBottom="60dp"
android:id="#+id/pager">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none"
android:overScrollMode="never">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
android:orientation="vertical">
</LinearLayout>
</ScrollView>
</android.support.v4.view.ViewPager>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="bottom">
<android.support.design.widget.TabLayout
android:layout_width="match_parent"
android:layout_height="30dp"
android:id="#+id/tabs"
app:tabMode="scrollable"
app:tabSelectedTextColor="#color/colorPrimaryDark"
app:tabTextColor="#color/tab_text"
app:tabIndicatorColor="#android:color/transparent"
app:tabBackground="#drawable/selected_tab_color"
style="#style/MyCustomTabLayout"/>
<include layout="#layout/toolbar" android:id="#+id/toolbar_layout"/>
</LinearLayout>
</RelativeLayout>
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="304dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:clickable="true"
android:background="#ffffff">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/uno"
android:text="Button to Activity1"/>
</LinearLayout>
</ScrollView>
</LinearLayout>
classe1.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent">
<FrameLayout
android:layout_height="match_parent"
android:layout_width="match_parent"
android:layout_marginBottom="30dp"
android:id="#+id/content_frame">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none"
android:overScrollMode="never">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="CLASSE 1"
android:textSize="35sp"
android:gravity="center"/>
</LinearLayout>
</ScrollView>
</FrameLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="bottom">
<include layout="#layout/toolbar" android:id="#+id/toolbar_layout"/>
</RelativeLayout>
</RelativeLayout>
Your problem is that the super.onCreate() call in Activity1 is calling setContentView() again in MainActivity, which is completely replacing Activity1's layout set with its call to setContentView().
Since you want tabs in MainActivity but not the other Activities, your other Activities shouldn't extend MainActivity. Instead, you should create a base Activity with the DrawerLayout that all of your Activities extend, including MainActivity, and then add whichever Views you need in the individual subclasses.
In the base Activity, we'll override the setContentView() method to first set the base layout, setup the drawer and toggle, and then inflate the subclass's layout into the DrawerLayout's content View. Note that we do not call setContentView() in the base Activity's onCreate() method.
public abstract class BaseActivity extends AppCompatActivity {
protected Toolbar toolbar;
protected DrawerLayout mDrawerLayout;
protected ActionBarDrawerToggle mDrawerToggle;
protected TextView mTitle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
}
#Override
public void setContentView(int layoutResID) {
super.setContentView(R.layout.activity_base);
toolbar = (Toolbar) findViewById(R.id.toolbar_layout);
mTitle = (TextView) toolbar.findViewById(R.id.toolbar_title);
mTitle.setText(R.string.app_name);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayShowTitleEnabled(false);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
//this is inside the drawer layout
Button button1 = (Button)findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(BaseActivity.this, Activity1.class);
startActivity(intent);
}
});
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerToggle = new ActionBarDrawerToggle(this,
mDrawerLayout,
null,
R.string.drawer_open,
R.string.drawer_close) {
public void onDrawerClosed(View v) {
super.onDrawerClosed(v);
invalidateOptionsMenu();
syncState();
}
public void onDrawerOpened(View v) {
super.onDrawerOpened(v);
invalidateOptionsMenu();
syncState();
}
};
mDrawerLayout.addDrawerListener(mDrawerToggle);
mDrawerToggle.setDrawerIndicatorEnabled(false);
mDrawerToggle.syncState();
getLayoutInflater().inflate(layoutResID,
(ViewGroup) findViewById(R.id.content));
}
}
The base layout is pretty much the same, except everything specific to MainActivity is removed.
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<include layout="#layout/toolbar" android:id="#+id/toolbar_layout"/>
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout"
android:layout_width="304dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:clickable="true"
android:background="#ffffff">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/button1"
android:text="Button to Activity1"/>
</LinearLayout>
</ScrollView>
</LinearLayout>
</android.support.v4.widget.DrawerLayout>
In MainActivity, we no longer need to setup the drawer and toggle.
public class MainActivity extends BaseActivity {
private CollectionPagerAdapter mCollectionPagerAdapter;
private ViewPager mViewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mCollectionPagerAdapter = new CollectionPagerAdapter(
getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.pager);
mViewPager.setAdapter(mCollectionPagerAdapter);
TabLayout tabs = (TabLayout)findViewById(R.id.tabs);
tabs.setupWithViewPager(mViewPager);
}
...
}
And the layout for MainActivity is now basically just the ViewPager and TabLayout.
<LinearLayout 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">
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:id="#+id/pager">
...
</android.support.v4.view.ViewPager>
<android.support.design.widget.TabLayout
android:layout_width="match_parent"
android:layout_height="30dp"
android:id="#+id/tabs"
app:tabMode="scrollable"
app:tabSelectedTextColor="#color/colorPrimaryDark"
app:tabTextColor="#color/tab_text"
app:tabIndicatorColor="#android:color/transparent"
app:tabBackground="#drawable/selected_tab_color"
style="#style/MyCustomTabLayout" />
</LinearLayout>
Then, to accomplish everything in Activity1 that your posted code is doing, all we need is this, since the Toolbar and title TextView are now in BaseActivity.:
public class Activity1 extends BaseActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.classe1);
mTitle.setText("Activity 1");
}
}
And the layout for Activity1 can be pared down significantly:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="none"
android:overScrollMode="never">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="CLASSE 1"
android:textSize="35sp"
android:gravity="center"/>
</LinearLayout>
</ScrollView>
You call setContentView two times in the Activity1 onCreate method, the first time with R.layout.classe1 and the second time with R.layout.activity_main (when you call the super.onCreate). The last setContentView wins, your problem is here.
I'm using eclipse to code my android app and I'm wondering how I can change the background image of my MainActivity when I click a button. I have img1.png and img2.png. The background is currently set on img1.png with the following xml code:
<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:background="#drawable/img1"
tools:context=".MainActivity" >
<Button
android:id="#+id/btn1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="46dp"
android:layout_marginTop="55dp"
android:background="#android:color/transparent"
android:text="" />
</RelativeLayout>
I'm just unsure what java code I would use to change the background image on btn1 click.
This code can be used to set background image programmattically
RelativeLayout layout =(RelativeLayout)findViewById(R.id.relativelayout);
layout.setBackgroundResource(R.drawable.img1);
This could be a solution.
In your layout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/lyt_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/img1"
tools:context=".MainActivity" >
In your Activity
RelativeLayout layout;
public void onCreate(Bundle savedInstanceState){
super.onCreate(Bundle savedInstanceState);
setContentView(your_xml.xml);
layout = (RelativeLayout) findById(R.id.lyt_main);
button = (Button) findById(R.id.lyt_main);
button.setOnClickListener(new OnClickListener{
public void onClick(View v) {
layout.setBackgroundDrawable(your_image));
}
});
}
Add android ID to Your Layout:
<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:background="#drawable/img1"
android:id="#+id/rlayout"
tools:context=".MainActivity" >
...
</RelativeLayout>
Now In Your MainActivity.java :
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.btn1);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
RelativeLayout rlayot = (RelativeLayout) findViewById(R.id.rlayout);
rlayot.setBackgroundResource(R.drawable.img2);
}
});
}
I have looked at posts on Stack Overflow and at tutorials on other websites, and I cannot understand how to use TabHost. Can someone please explain it to me and maybe send me a link to a tutorial?
In ManiActivity extends TabActivity
public class MainActivity extends TabActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
TabHost mTabHost = getTabHost();
mTabHost.addTab(mTabHost.newTabSpec("first").setIndicator("First").setContent(new Intent(this ,FirstActivity.class )));
mTabHost.addTab(mTabHost.newTabSpec("second").setIndicator("Second").setContent(new Intent(this , SecondActivity.class )));
mTabHost.setCurrentTab(0);
}
}
In this activity not use layout "activity_main.xml" .
Tabhost mTabHost = getTabHost(); is create main tab.
mTabHost.newTabSpec("first") is create tabspec id "first".
setIndicator("First") is create text "First" in title tab.
setContent(new Intent(this ,FirstActivity.class )) is use content from FirstActivity.class ( FirstActivity.java )
mTabHost.addTab(....) is add spectab to main tab
mTabHost.setCurrentTab(0) is defult tab when start page.
FirstActivity.java
public class FirstActivity extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView( R.layout.first_layout );
}
}
SecondActivity.java
public class SecondActivity extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView( R.layout.second_layout );
}
}
"R.layout.first_layout" is content from first_layout.xml
"R.layout.second_layout" is content from second_layout.xml
In AndroidManifest.xml add activity name ".FirstActivity" and ".SecondActivity" in example xml.
Finish!!!!!
First of all while TabHost is not deprecated, TabActivity on other hand is deprecated due to Fragment API.
There are two ways to use TabHost; using Fragment via FragmentTabHost and using TabHost.TabContentFactory.
1. Using Fragment via FragmentTabHost
This sample code show you how to use TabHost in Activity.
FragmentTabHostActivity.java
public class FragmentTabHostActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_tab_host_activity);
FragmentTabHost fragmentTabHost = (FragmentTabHost) findViewById(android.R.id.tabhost);
fragmentTabHost.setup(this, getSupportFragmentManager(), android.R.id.tabcontent);
fragmentTabHost.addTab(getTabSpec1(fragmentTabHost), Tab1Fragment.class, null);
fragmentTabHost.addTab(getTabSpec2(fragmentTabHost), Tab2Fragment.class, null);
}
private TabHost.TabSpec getTabSpec1(FragmentTabHost tabHost) {
return tabHost.newTabSpec("First Tab")
.setIndicator("Tab1");
}
private TabHost.TabSpec getTabSpec2(FragmentTabHost tabHost) {
return tabHost.newTabSpec("Second Tab")
.setIndicator("Tab 2");
}
}
fragment_tab_host_activity.xml
<android.support.v4.app.FragmentTabHost
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TabWidget
android:id="#android:id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
</android.support.v4.app.FragmentTabHost>
Actually by using Fragment, you can use Tab inside a Fragment (Android docs).
2. Using TabHost.ContentFactory
TabHostActivity.java
public class TabHostActivity extends AppCompatActivity implements TabHost.TabContentFactory {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TabHost tabHost = (TabHost) findViewById(android.R.id.tabhost);
tabHost.setup();
tabHost.addTab(getTabSpec1(tabHost));
tabHost.addTab(getTabSpec2(tabHost));
}
private TabHost.TabSpec getTabSpec1(TabHost tabHost) {
return tabHost.newTabSpec("First Tab")
.setIndicator("Tab1")
.setContent(this);
}
private TabHost.TabSpec getTabSpec2(TabHost tabHost) {
return tabHost.newTabSpec("Second Tab")
.setIndicator("Tab 2")
.setContent(this);
}
#Override
public View createTabContent(String tag) {
return LayoutInflater.from(this).inflate(R.layout.activity_tab_1, null);
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<TabHost
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TabWidget
android:id="#android:id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
</TabHost>
However, I personally recommend using newest Material Design style TabLayout class.