Question

我正在使用解析通过自定义接收器将Json通知推送到我的应用，因为我想导航到应用中的不同位置，这取决于我收到的Json值，我有2个案例要导航：

a）7

b）1,2,3,4,5,6

案例a会打开activity，这样可以正常工作。 case b在`MainActivity中打开fragment。＆＃34;问题在这里。＆＃34;

我尝试用正常意图打开MainActivity然后用片段替换它的容器。

当我尝试打开案例b时，我在此代码段的第三行中获得了ClassCastException，因为它无法将BaseClass上下文转换为v4片段。当我只给出属于接收器上下文的context时，我得到了同样的异常。

intent = new Intent(context, MainScreen.class);
Fragment fragment = new NotificationFragment();
FragmentTransaction transaction = ((FragmentActivity) context.getApplicationContext()).getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.container, fragment).commit();

这是个例外：

FATAL EXCEPTION: main
Process: com.myapp.SomeApp, PID: 9639
java.lang.RuntimeException: Unable to start receiver com.myapp.SomeApp.Receivers.NotifyReceiver: java.lang.ClassCastException: com.myapp.SomeApp.utils.BaseClass cannot be cast to android.support.v4.app.FragmentActivity
 at android.app.ActivityThread.handleReceiver(ActivityThread.java:2616)
 at android.app.ActivityThread.access$1700(ActivityThread.java:151)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1380)
 at android.os.Handler.dispatchMessage(Handler.java:102)
 at android.os.Looper.loop(Looper.java:135)
 at android.app.ActivityThread.main(ActivityThread.java:5254)
 at java.lang.reflect.Method.invoke(Native Method)
 at java.lang.reflect.Method.invoke(Method.java:372)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
 at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:114)
 Caused by: java.lang.ClassCastException: com.myapp.SomeApp.utils.BaseClass cannot be cast to android.support.v4.app.FragmentActivity
 at com.myapp.SomeApp.Receivers.NotifyReceiver.onReceive(NotifyReceiver.java:52)
 at android.app.ActivityThread.handleReceiver(ActivityThread.java:2609)
 at android.app.ActivityThread.access$1700(ActivityThread.java:151) 
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1380) 
 at android.os.Handler.dispatchMessage(Handler.java:102) 
 at android.os.Looper.loop(Looper.java:135) 
 at android.app.ActivityThread.main(ActivityThread.java:5254) 
 at java.lang.reflect.Method.invoke(Native Method) 
 at java.lang.reflect.Method.invoke(Method.java:372) 
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
 at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:114)

这是完整的接收者代码：

public class NotifyReceiver extends BroadcastReceiver {

private String title, itemID, notifyType;
private int id;

@Override
public void onReceive(Context context, Intent intent) {

    if (intent != null) {
        try {
            String response = intent.getExtras().getString("com.parse.Data");

            JSONObject data = new JSONObject(response);
            itemID = data.getString("ItemID");
            notifyType = data.getString("NotificationTypeID");
            title = data.getString("alert");

            id = Integer.parseInt(notifyType);
        } catch (JSONException e) {
            Log.e("NotifyReceiver", e.getMessage());
        }
    }
    if (id == 7) {
        intent = new Intent(context, TendersActivity.class);
    } else {
        intent = new Intent(context, MainScreen.class);
        Fragment fragment = new NotificationFragment();
        FragmentTransaction transaction =
                ((FragmentActivity) context.getApplicationContext())
                        .getSupportFragmentManager().beginTransaction();
        transaction.replace(R.id.container, fragment).commit();
    }
    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);

    Notification notify = new NotificationCompat.Builder(context)
            .setContentTitle(context.getResources().getString(R.string.app_name))
            .setContentText(title)
            .setSmallIcon(R.drawable.ic_stat_notify)
            .setContentIntent(pendingIntent)
            .setVibrate(new long[]{250, 250, 250, 250})
            .setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION))
            .setAutoCancel(true)
            .build();

    NotificationManager manager = (NotificationManager)
            context.getSystemService(Context.NOTIFICATION_SERVICE);
    manager.notify(0, notify);
    }
}

Answer 1

请使用此代码替换您的其他部分：

else {
        intent = new Intent(context, MainScreen.class);
        resultIntent.putExtra("From", "notifyFrag");
    }

并在MainScreen.class检查是否使用此代码从通知密钥调用活动：

String type = getIntent().getStringExtra("From");
if (type != null) {
    switch (type) {
        case "notifyFrag":
            Fragment fragment = new NotificationFragment();
            FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
            transaction.replace(R.id.container, fragment).commit();
            break;
    }
}

希望这有帮助。

Answer 2

避免使用此行。这是BaseClass上下文的来源。

((FragmentActivity) context.getApplicationContext())

在后台应用程序时从通知中打开片段

2 个答案: