android - How to know an application is Launched ? using Broadcast receiver

Question

There is any way to know if any Application is opened, then MainActivity of this Application(Launcher activity) is launched. So my question is that, how could I know that MainActivity(Launcher activity) detail using Broadcast Receiver?

Answer 1

这可以通过使用粘性服务来完成。

   @Override
public int onStartCommand(Intent intent, int flags, int startId) 
{

Timer timer  =  new Timer();
timer.scheduleAtFixedRate(new TimerTask() {

    public void run() 
    {
        final ActivityManager activityManager  =  (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);
        final List<RunningTaskInfo> services  =  activityManager.getRunningTasks(Integer.MAX_VALUE);
             for (int i = 0; i < services.size(); i++) {
                 if(!stalkList.contains(services.get(i).baseActivity.getPackageName()))
                 {
                      // you may broad cast a new application launch here.  
                      stalkList.add(services.get(i).baseActivity.getPackageName());
                 }
            }

             List<RunningAppProcessInfo> procInfos = activityManager.getRunningAppProcesses();
            for(int i = 0; i < procInfos.size(); i++) {  

                ArrayList<String> runningPkgs = new ArrayList<String>(Arrays.asList(procInfos.get(i).pkgList));

                Collection diff = subtractSets(runningPkgs, stalkList); 

                if(diff != null)
                {
                    stalkList.removeAll(diff);
                }
           }


    }
}, 20000, 6000);  // every 6 seconds


return START_STICKY;
}




private RunningAppProcessInfo getForegroundApp() {
RunningAppProcessInfo result = null, info = null;

final ActivityManager activityManager  =  (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);

List <RunningAppProcessInfo> l = activityManager.getRunningAppProcesses();
Iterator <RunningAppProcessInfo> i = l.iterator();
while(i.hasNext()) {
    info = i.next();
    if(info.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND
            && !isRunningService(info.processName)) {
        result = info;
        break;
    }
}
return result;
}    

private boolean isRunningService(String processName) {
if(processName == null)
    return false;

RunningServiceInfo service;

final ActivityManager activityManager = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);

List <RunningServiceInfo> l = activityManager.getRunningServices(9999);
Iterator <RunningServiceInfo> i = l.iterator();
while(i.hasNext()){
    service = i.next();
    if(service.process.equals(processName))
        return true;
}
return false;
}    

private boolean isRunningApp(String processName) {
if(processName == null)
    return false;

RunningAppProcessInfo app;

final ActivityManager activityManager = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);

List <RunningAppProcessInfo> l = activityManager.getRunningAppProcesses();
Iterator <RunningAppProcessInfo> i = l.iterator();
while(i.hasNext()){
    app = i.next();
    if(app.processName.equals(processName) && app.importance != RunningAppProcessInfo.IMPORTANCE_SERVICE)
        return true;
}
return false;
}


private boolean checkifThisIsActive(RunningAppProcessInfo target){
boolean result = false;
ActivityManager.RunningTaskInfo info;

if(target == null)
    return false;

final ActivityManager activityManager = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);

List <ActivityManager.RunningTaskInfo> l = activityManager.getRunningTasks(9999);
Iterator <ActivityManager.RunningTaskInfo> i = l.iterator();

while(i.hasNext()){
    info=i.next();
    if(info.baseActivity.getPackageName().equals(target.processName)) {
        result = true;
        break;
    }
}

return result;
}  


// what is in b that is not in a ?
public static Collection subtractSets(Collection a, Collection b)
{
Collection result = new ArrayList(b);
result.removeAll(a);
return result;
}