Android 切换到后台监控

//activity中
public boolean isAppOnForeground() {
// Returns a list of application processes that are running on the
// device

ActivityManager activityManager = (ActivityManager) getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
String packageName = getApplicationContext().getPackageName();

List<ActivityManager.RunningAppProcessInfo> appProcesses = activityManager
.getRunningAppProcesses();
if (appProcesses == null)
return false;

for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
// The name of the process that this object is associated with.
if (appProcess.processName.equals(packageName)
&& appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
return true;
}
}

return false;
}

public class AppStateManage extends Observable{
private AppState m_iAppState = AppState.INIT;
private static AppStateManage instance;

private AppStateManage() {
}

public static AppStateManage getInstance() {
if (instance == null) {
synchronized (AppStateManage.class) {
if (instance == null) {
instance = new AppStateManage();
}
}
}
return instance;
}

public void changeAppState(AppState appState) {
m_iAppState = appState;
notifyChange(appState);
}

private void notifyChange(AppState appState) {
setChanged();
notifyObservers(appState);
}

public enum AppState {
INIT,
RESUME,
GO_BACKGROUND;
}

public boolean isGoBackgroundState() {
if (m_iAppState == AppState.GO_BACKGROUND) {
return true;
}

return false;
}

public AppState getAppState() {
return m_iAppState;
}
}

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (this instanceof SplashActivity) {
// 如果是第一次启动应用 清一下通知栏
AppStateManage.getInstance().changeAppState(AppStateManage.AppState.INIT);
} else {
AppStateManage.getInstance().changeAppState(AppStateManage.AppState.RESUME);
}
}

@Override
protected void onResume() {
super.onResume();

if (AppStateManage.getInstance().isGoBackgroundState()) {
// 如果是从后台切换到前台 清一下通知栏
AppStateManage.getInstance().changeAppState(AppStateManage.AppState.RESUME);
} else {
AppStateManage.getInstance().changeAppState(AppStateManage.AppState.RESUME);
}
}

@Override
protected void onStop() {
super.onStop();
m_iStop = 1;
if (!isAppOnForeground()) {
AppStateManage.getInstance().changeAppState(AppStateManage.AppState.GO_BACKGROUND);
}
}