Question

我已经集成了一个用于推送通知的信号库。我想在应用未运行时通过点击推送通知打开特定活动我正在接收推送通知但是当我点击通知时，应用程序崩溃了。这是我的通知接收器代码

public class ExampleNotificationOpenedHandler implements OneSignal.NotificationOpenedHandler 
{

Context context;
@Override
public void notificationOpened(OSNotificationOpenResult result) {
    OSNotificationAction.ActionType actionType = result.action.type;
    JSONObject data = result.notification.payload.additionalData;
    String customKey;

    if (data != null) {
        customKey = data.optString("customkey", null);
        if (customKey != null)
            Log.e("OneSignalExample", "customkey set with value: " + customKey);
    }

    if (actionType == OSNotificationAction.ActionType.ActionTaken)
        Log.i("OneSignalExample", "Button pressed with id: " + result.action.actionID);

     Intent intent = new Intent(context, User_Detail.class);
     intent.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT | Intent.FLAG_ACTIVITY_NEW_TASK);
     context.startActivity(intent);
}

这是我的错误消息

Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference

Answer 1

我错过了在onReceivedMethod

之前在类中构建构造函数

Context context2;

ExampleNotificationOpenedHandler(Context context) {
    context2 = context;
}

@Override
public void notificationOpened(OSNotificationOpenResult result) {
    OSNotificationAction.ActionType actionType = result.action.type;
    JSONObject data = result.notification.payload.additionalData;
    String customKey;

    Intent intent = new Intent(context2,User_Detail.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT | Intent.FLAG_ACTIVITY_NEW_TASK);
    context2.startActivity(intent);


   if (data != null) {
        customKey = data.optString("customkey", null);
        if (customKey != null)
            Log.e("OneSignalExample", "customkey set with value: " + customKey);
    }

    if (actionType == OSNotificationAction.ActionType.ActionTaken)
    {
        Log.i("OneSignalExample", "Button pressed with id: " + result.action.actionID);


    }

并在Application类

中传递上下文

  @Override
public void onCreate() {
    super.onCreate();
    mInstance = this;


    OneSignal.startInit(this)
            .setNotificationOpenedHandler(new ExampleNotificationOpenedHandler(this))
            .init();

}

Answer 2

这意味着context变量为空。

如果您查看Intent的源代码并选择了construcor

public Intent(Context packageContext, Class<?> cls) {
    mComponent = new ComponentName(packageContext, cls);
}

ComponentName construcor

public ComponentName(Context pkg, String cls) {
     if (cls == null) throw new NullPointerException("class name is null");
     mPackage = pkg.getPackageName(); //here you get crash
     mClass = cls;
 }

您可以使用DI来提供上下文，例如Dagger2。

或实现应用程序类

public class DemoApp extends Application {

    private static DemoApp instance;

    @Override
    public void onCreate() {
        instance = this;
        super.onCreate();
    }

    public static DemoApp getInstance() {
        return instance;
    }

}

在你的清单中

<application
        android:name=".demo.DemoApp"

OneSignal推送通知单击以打开活动

2 个答案: