安卓：NPE试图activityForResult与ACTION_APPWIDGET_PICK意图 [英] Android:NPE while trying to activityForResult with ACTION_APPWIDGET_PICK intent

问题描述

我有一个问题，然后试图把与 AppWidgetManager.ACTION_APPWIDGET_PICK 的意图是有问题somethere Android的AppWidget生态系统里面，我可以从日志中看到。 所以，我做错了什么？
请参阅下面

I have a problem then trying to put an intent with AppWidgetManager.ACTION_APPWIDGET_PICK there is a problem somethere inside of android AppWidget ecosystem as I can see from the logs. So that I doing wrong?
See sample code and stack trace below

public class NPEDemoActivity extends Activity {

    private final static int HOST_CODE = 1024;

    private AppWidgetHost host;
    private AppWidgetManager manager;
    private int PICK_WIDGET_RC = 1;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);        
        setContentView(R.layout.main);
        host = new AppWidgetHost(this, HOST_CODE);
        host.startListening();
        manager = AppWidgetManager.getInstance(this);
        Button b = (Button)findViewById(R.id.Button01);
        b.setOnClickListener(new View.OnClickListener() {

    		@Override
    		public void onClick(View v) {
    			int nextId = host.allocateAppWidgetId();
    			Intent pickIntent = new Intent(AppWidgetManager.ACTION_APPWIDGET_PICK);				
                pickIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, nextId);
                startActivityForResult(pickIntent, PICK_WIDGET_RC);   
    		}
    	});
    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
    }
}

从日志猫堆栈跟踪：

stack trace from log cat:

10-15 17:33:06.873: ERROR/AndroidRuntime(821): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.android.settings/com.android.settings.AppWidgetPickActivity}: java.lang.NullPointerException
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2401)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread.access$2100(ActivityThread.java:116)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.os.Looper.loop(Looper.java:123)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread.main(ActivityThread.java:4203)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at java.lang.reflect.Method.invokeNative(Native Method)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at java.lang.reflect.Method.invoke(Method.java:521)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at dalvik.system.NativeStart.main(Native Method)
10-15 17:33:06.873: ERROR/AndroidRuntime(821): Caused by: java.lang.NullPointerException
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.settings.AppWidgetPickActivity.putAppWidgetItems(AppWidgetPickActivity.java:170)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.settings.AppWidgetPickActivity.putCustomAppWidgets(AppWidgetPickActivity.java:132)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.settings.AppWidgetPickActivity.getItems(AppWidgetPickActivity.java:208)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.settings.ActivityPicker.onCreate(ActivityPicker.java:99)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at com.android.settings.AppWidgetPickActivity.onCreate(AppWidgetPickActivity.java:63)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
10-15 17:33:06.873: ERROR/AndroidRuntime(821):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2364)

另外一个小的问题，在这种机器人项目的支持com.android.settings住呢？ （我坚持使用Windows所以不能用回购不幸） 帮助真的是preciated。

Another small question, in which of android projects does com.android.settings live in? (I'm stuck with windows so can't use repo unfortunatly) Help really apreciated.

推荐答案

看起来像Android设置的错误，如果你想appwidget挑不指定，你会失败的任何额外的部件，在谷歌code填补了一个问题链接

Looks like a bug in android settings, if you trying to pick appwidget without any extra widgets specified you'll fail, filled an issue at google code link

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