Problem running android HelloTabWidget example - NullPointerException on addTab()

Posted by Poindextrose on Stack Overflow See other posts from Stack Overflow or by Poindextrose
Published on 2010-02-21T20:35:02Z Indexed on 2010/05/13 0:34 UTC
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I've tried the Tab Layout example, and I've also fixed the few typos in the example (and added all the activities to the manifest). However, when I run it on the emulator I get a NullPointerException on the first line that says

tabHost.addTab(spec);

So my question, of course, is. What is wrong with the example that would cause this exception? I'm using Eclipse Galileo and set the target package as Android 1.5. So far I've had no other problems with the other examples on the android dev site.

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 {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) throws RuntimeException {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    Resources res = getResources(); // Resource object to get Drawables
    TabHost tabHost = getTabHost();  // The activity TabHost
    TabHost.TabSpec spec;  // Reusable TabSpec for each tab
    Intent intent;  // Reusable Intent for each tab

    // Create an Intent to launch an Activity for the tab (to be reused)
    //final Context context = getApplicationContext();
    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); //******** NullPointerException after running this line

    // 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))
            .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))
            .setContent(intent);
    tabHost.addTab(spec);

    tabHost.setCurrentTabByTag("artists");
}
}

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>

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