Android Tutorial 'HelloTabWidget'
I think I've added the code exactly as it says on the android tab layout tutorial and corrected any problems. The app seems to compile ok but when I run it on the emulator it says 'The application * has stopped unexpectedly please try again'. Here are my files please let me know if you see any problem with the code.
there are 4 separate activity files.
package com.example.HelloTabWidget;
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.*;
public class AlbumsActivity extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resou开发者_JAVA百科rces res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, ArtistsActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("artists").setIndicator("Artists",
res.getDrawable(R.drawable.ic_tab_artists))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, AlbumsActivity.class);
spec = tabHost.newTabSpec("albums").setIndicator("Albums",
res.getDrawable(R.drawable.ic_tab_artists_grey))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, SongsActivity.class);
spec = tabHost.newTabSpec("songs").setIndicator("Songs",
res.getDrawable(R.drawable.ic_tab_artists_white))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(2);
}
}
package com.example.HelloTabWidget;
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
public class ArtistsActivity extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, ArtistsActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("artists").setIndicator("Artists",
res.getDrawable(R.drawable.ic_tab_artists))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, AlbumsActivity.class);
spec = tabHost.newTabSpec("albums").setIndicator("Albums",
res.getDrawable(R.drawable.ic_tab_artists_grey))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, SongsActivity.class);
spec = tabHost.newTabSpec("songs").setIndicator("Songs",
res.getDrawable(R.drawable.ic_tab_artists_white))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(2);
}
}
package com.example.HelloTabWidget;
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
public class HelloTabWidget extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, ArtistsActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("artists").setIndicator("Artists",
res.getDrawable(R.drawable.ic_tab_artists))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, AlbumsActivity.class);
spec = tabHost.newTabSpec("albums").setIndicator("Albums",
res.getDrawable(R.drawable.ic_tab_artists_grey))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, SongsActivity.class);
spec = tabHost.newTabSpec("songs").setIndicator("Songs",
res.getDrawable(R.drawable.ic_tab_artists_white))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(2);
}}
package com.example.HelloTabWidget;
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
public class SongsActivity extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, ArtistsActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("artists").setIndicator("Artists",
res.getDrawable(R.drawable.ic_tab_artists))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, AlbumsActivity.class);
spec = tabHost.newTabSpec("albums").setIndicator("Albums",
res.getDrawable(R.drawable.ic_tab_artists_grey))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, SongsActivity.class);
spec = tabHost.newTabSpec("songs").setIndicator("Songs",
res.getDrawable(R.drawable.ic_tab_artists_white))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(2);
}}
This is the artists xml file in res/drawable (the images are present in res/drawable as well)
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- When selected, use grey -->
<item android:drawable="@drawable/ic_tab_artists_grey"
android:state_selected="true" />
<!-- When not selected, use white-->
<item android:drawable="@drawable/ic_tab_artists_white" />
</selector>
This is the 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="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp">
<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"
android:padding="5dp" />
</LinearLayout>
</TabHost>
this is the android manifest file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.HelloTabWidget" android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="7" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".HelloTabWidget" android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".AlbumsActivity" android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar">
</activity>
<activity android:name=".ArtistsActivity" android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar">
</activity>
<activity android:name=".SongsActivity" android:label="@string/app_name"
android:theme="@android:style/Theme.NoTitleBar">
</activity>
</application>
</manifest>
I have spend ages going over this looking for typos and found nothing, I've also spent ages looking on forums and nothing seems to adequately address why this doesn't work - I am new to this though so could be mistaken and maybe dont understand the answers but i dont think thats it.
At the moment all your Activity.java classes look exactly the same as the HelloTabWidget.java which they probably shouldn't
Try:
HelloTabWidget.java
package com.example.HelloTabWidget;
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
public class HelloTabWidget extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources();
TabHost tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("artists").setIndicator("Artists",res.getDrawable(R.drawable.ic_tab_artists)).setContent(new Intent(this, ArtistsActivity.class)));
tabHost.addTab(tabHost.newTabSpec("albums").setIndicator("Albums",res.getDrawable(R.drawable.ic_tab_artists)).setContent(new Intent(this, AlbumsActivity.class)));
tabHost.addTab(tabHost.newTabSpec("songs").setIndicator("Songs",res.getDrawable(R.drawable.ic_tab_artists)).setContent(new Intent(this, SongsActivity.class)));
tabHost.setCurrentTab(2);
}
}
ArtistsActivity.java
package com.example.HelloTabWidget;
import android.app.Activity;
import android.os.Bundle;
public class ArtistsActivity extends Activity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.artistslayout);
// your code for this activity ... (not the same as HelloTabWidget.java)
}
}
And the same for the other 2 Activity classes.
精彩评论