我收到一条错误说明：FATAL EXCEPTION：main java.lang.RuntimeException：无法在行上启动活动ComponentInfo：
actionBar.setCustomView(R.layout.actionbar_custom_view_home);
public class MainActivity extends YouTubeBaseActivity implements
YouTubePlayer.OnInitializedListener {
private VideosListView listView;
private ActionBarDrawerToggle actionBarDrawerToggle;
private ActionBarDrawerToggle mDrawerToggle;
public static final String API_KEY = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";
public static final String VIDEO_ID = "o7VVHhK9zf0";
private DrawerLayout drawerLayout;
private ListView drawerListView;
private String[] drawerListViewItems;
ScrollView mainScrollView;
Button fav_up_btn1;
Button fav_dwn_btn1;
private YouTubePlayerView youTubePlayerView;
private YouTubeThumbnailView youTubeThumbnailView1;
private YouTubePlayer youTubePlayer;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_ACTION_BAR);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
ImagePagerAdapter adapter = new ImagePagerAdapter();
viewPager.setAdapter(adapter);
final ActionBar actionBar = getActionBar();
actionBar.setCustomView(R.layout.actionbar_custom_view_home);
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayShowCustomEnabled(true);
Bitmap d = BitmapFactory.decodeResource(this.getResources(),
R.drawable.selstation_up_btn);
ImageView imgView = (ImageView) findViewById(R.id.selstation_up_btn);
imgView.setImageBitmap(d);
// get list items from strings.xml
drawerListViewItems = getResources().getStringArray(R.array.items);
// get ListView defined in activity_main.xml
drawerListView = (ListView) findViewById(R.id.left_drawer);
// Set the adapter for the list view
drawerListView.setAdapter(new ArrayAdapter<String>(this,
R.layout.drawer_listview_item, drawerListViewItems));
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
actionBarDrawerToggle = new ActionBarDrawerToggle(this, /* host Activity */
drawerLayout, /* DrawerLayout object */
R.drawable.ic_drawer, /* nav drawer icon to replace 'Up' caret */
R.string.drawer_open, /* "open drawer" description */
R.string.drawer_close /* "close drawer" description */
);
drawerLayout.setDrawerListener(actionBarDrawerToggle);
getActionBar().setDisplayHomeAsUpEnabled(true);
drawerLayout.setDrawerShadow(R.drawable.drawer_shadow,
GravityCompat.START);
youTubePlayerView = (YouTubePlayerView) findViewById(R.id.youtubeplayerview);
youTubePlayerView.initialize(API_KEY, this);
mainScrollView = (ScrollView) findViewById(R.id.groupScrollView);
fav_up_btn1 = (Button) findViewById(R.id.fav_up_btn1);
fav_up_btn1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
boolean favIsUp = fav_up_btn1
.getBackground()
.getConstantState()
.equals(getResources().getDrawable(
R.drawable.fav_up_btn1).getConstantState());
// set the background
fav_up_btn1
.setBackgroundResource(favIsUp ? R.drawable.fav_dwn_btn1
: R.drawable.fav_up_btn1);
}
});
listView = (VideosListView) findViewById(R.id.videosListView);
// Here we are adding this activity as a listener for when any row in
// the List is 'clicked'
// The activity will be sent back the video that has been pressed to do
// whatever it wants with
// in this case we will retrieve the URL of the video and fire off an
// intent to view it
listView.setOnVideoClickListener((VideoClickListener) this);
new GetYouTubeUserVideosTask(responseHandler, "blundellp").execute();
}
Handler responseHandler = new Handler() {
public void handleMessage(Message msg) {
populateListWithVideos(msg);
};
};
private void populateListWithVideos(Message msg) {
Library lib = (Library) msg.getData().get(
GetYouTubeUserVideosTask.LIBRARY);
listView.setVideos(lib.getVideos());
}
@Override
protected void onStop() {
responseHandler = null;
super.onStop();
}
// This is the interface method that is called when a video in the listview
// is clicked!
// The interface is a contract between this activity and the listview
public void onVideoClicked(Video video) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(video.getUrl()));
startActivity(intent);
}
private class ImagePagerAdapter extends PagerAdapter {
private int[] mImages = new int[] { R.drawable.classical_up_btn,
R.drawable.country_up_btn, R.drawable.dance_up_btn,
R.drawable.hiphop_up_btn };
public int getCount() {
return mImages.length;
}
public boolean isViewFromObject(View view, Object object) {
return view == ((ImageView) object);
}
public Object instantiateItem(ViewGroup container, int position) {
Context context = MainActivity.this;
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(
R.dimen.padding_medium);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.FIT_XY);
imageView.setImageResource(mImages[position]);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
public void destroyItem(View container, int position, Object object) {
((ViewPager) container).removeView((View) object);
}
}
@Override
public void onInitializationFailure(Provider arg0,
YouTubeInitializationResult arg1) {
// TODO Auto-generated method stub
}
@Override
public void onInitializationSuccess(Provider provider,
YouTubePlayer player, boolean wasRestored) {
youTubePlayer = player;
if (!wasRestored) {
player.cueVideo(VIDEO_ID);
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="horizontal" >
<ImageView
android:id="@+id/actionBarLogo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="false"
android:focusable="false"
android:longClickable="false"
android:src="@drawable/ic_launcher" />
</LinearLayout>
12-04 11:18:40.998: D/AbsListView(4821): Get MotionRecognitionManager
12-04 11:18:41.053: D/AndroidRuntime(4821): Shutting down VM
12-04 11:18:41.053: W/dalvikvm(4821): threadid=1: thread exiting with uncaught exception (group=0x4126e2a0)
12-04 11:18:41.063: E/AndroidRuntime(4821): FATAL EXCEPTION: main
12-04 11:18:41.063: E/AndroidRuntime(4821): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.blundell.tut/com.blundell.tut.ui.phone.MainActivity}: java.lang.NullPointerException
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2110)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2135)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread.access$700(ActivityThread.java:140)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1237)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.os.Handler.dispatchMessage(Handler.java:99)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.os.Looper.loop(Looper.java:137)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread.main(ActivityThread.java:4921)
12-04 11:18:41.063: E/AndroidRuntime(4821): at java.lang.reflect.Method.invokeNative(Native Method)
12-04 11:18:41.063: E/AndroidRuntime(4821): at java.lang.reflect.Method.invoke(Method.java:511)
12-04 11:18:41.063: E/AndroidRuntime(4821): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1027)
12-04 11:18:41.063: E/AndroidRuntime(4821): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:794)
12-04 11:18:41.063: E/AndroidRuntime(4821): at dalvik.system.NativeStart.main(Native Method)
12-04 11:18:41.063: E/AndroidRuntime(4821): Caused by: java.lang.NullPointerException
12-04 11:18:41.063: E/AndroidRuntime(4821): at com.blundell.tut.ui.phone.MainActivity.onCreate(MainActivity.java:50)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.Activity.performCreate(Activity.java:5206)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
12-04 11:18:41.063: E/AndroidRuntime(4821): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
12-04 11:18:41.063: E/AndroidRuntime(4821): ... 11 more
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.blundell.tut"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="16"
android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:logo="@drawable/header_menu_up_btn"
android:theme="@style/AppTheme" >
<activity
android:name=".ui.phone.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ui.phone.Login"
android:label="@string/app_name" >
</activity>
<activity
android:name=".ui.phone.Splash"
android:label="@string/app_name" >
</activity>
</application>
</manifest>
我不确定我究竟缺少什么（布局存在并且没有错误）所以我不确定究竟是什么导致了这一点。
答案 0 :(得分：0)
请检查项目中的布局文件夹中是否有actionbar_custom_view_home.xml。我想这是缺失的。
答案 1 :(得分：0)
问题在于这一行：
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
如果您没有ActionBar，方法getActionBar（）将返回null。
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