android 前台 后台,Android对app在前台后台的监控

app在前台还是后台的判断有很多种，如：

1.在BaseActivity中对Activity的进行保存管理，可以通过根据当前的所有Activity的状态来判断应用是否是在前台显示。

2.在application中注册registerActivityLifecycleCallbacks()的回调，通过回调来判断是否在前台

public class MyApp extends Application {

private static final String TAG = "TEST_APP";

private static int mActivityCount;

@Override

public void onCreate() {

super.onCreate();

registerActivityLifecycleCallbacks(new ActivityLifecycleCallbacks() {

@Override

public void onActivityCreated(Activity activity, Bundle savedInstanceState) {

}

@Override

public void onActivityStarted(Activity activity) {

mActivityCount++;

if(mActivityCount == 1) {

Log.e(TAG, "后台->前台");

}

}

@Override

public void onActivityResumed(Activity activity) {

}

@Override

public void onActivityPaused(Activity activity) {

}

@Override

public void onActivityStopped(Activity activity) {

mActivityCount--;

if(mActivityCount == 0) {

Log.e(TAG, "前台->后台");

}

}

@Override

public void onActivitySaveInstanceState(Activity activity, Bundle outState) {

}

@Override

public void onActivityDestroyed(Activity activity) {

}

});

}

}

3.通过获取系统ActivityManager来判断。

4.其他方法

新增一个方法

使用LifecycleObserver来获取对应生命周期的回调，从而判断是前台还是后台

public class ProcessLifecycleObserver implements LifecycleObserver {

private static final String TAG = LogHelper.makeLogTag(ProcessLifecycleObserver.class);

public ProcessLifecycleObserver() {

}

@OnLifecycleEvent(Lifecycle.Event.ON_CREATE)

public void onProcessCreate() {

LogHelper.d(TAG, "onProcessCreate: ");

}

/**

* 进入前台

*/

@OnLifecycleEvent(Lifecycle.Event.ON_START)

public void onEnterForeground() {

Log.e(TAG, "onEnterForeground: ");

}

/**

* 进入后台

*/

@OnLifecycleEvent(Lifecycle.Event.ON_STOP)

public void onEnterBackground() {

Log.e(TAG, "onEnterBackground: ");

}

}

在项目的application中注册

public class ComicApps extends Application {

@Override

public void onCreate() {

ProcessLifecycleOwner.get().getLifecycle().addObserver(new ProcessLifecycleObserver());

}

}