Question

问题：应用程序不时会在启动时抛出异常，但并非总是如此。我不明白为什么有时会发生这种情况，但有时候不会发生。任何建议都会非常感激。

一些日志：

04-18 17:58:12.437: E/AndroidRuntime(26208): FATAL EXCEPTION: main
04-18 17:58:12.437: E/AndroidRuntime(26208): java.lang.RuntimeException: Unable to start receiver com.cm.clou.ContactsListUpdateReceiver: java.lang.NullPointerException
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.app.ActivityThread.handleReceiver(ActivityThread.java:1805)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.app.ActivityThread.access$2400(ActivityThread.java:117)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:981)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.os.Handler.dispatchMessage(Handler.java:99)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.os.Looper.loop(Looper.java:130)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.app.ActivityThread.main(ActivityThread.java:3683)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at java.lang.reflect.Method.invokeNative(Native Method)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at java.lang.reflect.Method.invoke(Method.java:507)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at dalvik.system.NativeStart.main(Native Method)
04-18 17:58:12.437: E/AndroidRuntime(26208): Caused by: java.lang.NullPointerException
04-18 17:58:12.437: E/AndroidRuntime(26208):    at com.cm.clou.ConversationsListActivity.notifyAdaper(ConversationsListActivity.java:270)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at com.cm.clou.ContactsListUpdateReceiver.onReceive(ContactsListUpdateReceiver.java:17)
04-18 17:58:12.437: E/AndroidRuntime(26208):    at android.app.ActivityThread.handleReceiver(ActivityThread.java:1794)

接收者代码：

public class ContactsListUpdateReceiver extends BroadcastReceiver {

    public static final String TAG = ContactsListUpdateReceiver.class.getSimpleName();

    @Override
    public void onReceive(Context context, Intent intent) {
        String message = intent.getStringExtra("message");
        if (message != null) {
            Log.d(TAG, "Uslishali otvet ot servisa po apdejtu contactov: " + message);
            ConversationsListActivity.notifyAdaper(context);
        }
    }

}

在清单中：

<receiver
    android:name="com.cm.clou.ContactsListUpdateReceiver"
    android:enabled="true"
    android:exported="false" >
    <intent-filter>
        <action android:name="com.cm.clou.ACTION_CONTACTS_LIST_UPDATE" />
    </intent-filter>
</receiver>

我的notifyAdaper代码：

private static ConversationsListCursorAdapter conversationsListCursorAdapter = null;
@SuppressLint("NewApi")
    public static void notifyAdaper(Context context) {

        Uri uri = ClouContentProvider.CONVERSATIONS_CONTENT_URI;
        Cursor cursor = null;

        if (android.os.Build.VERSION.SDK_INT < 11) {
            cursor = context.getContentResolver().query(uri, null, null, null, null);
        } else {
            CursorLoader cursorLoader = new CursorLoader(context, uri, null, null, null, null);
            cursor = cursorLoader.loadInBackground();
        }

        conversationsListCursorAdapter.changeCursor(cursor);
        conversationsListCursorAdapter.notifyDataSetChanged();
    }

Answer 1

看起来你永远不会实例化conversationsListCursorAdapter。

您需要在访问它之前对其进行实例化。

无法启动接收器异常

1 个答案: