doInBackground like you have it is not the way to do that -- what you have coded is called spinning
Kostya Vasilyev's explanation is clearer than mine and will move you in the direction of correct code if you take the suggestion and continue to work it but rather than doing a spin-lock as a wait we use instead a programming approach known as interfaces - sometimes called callbacks - which will be in the AsyncTask documents rather than detaching what you do is call dot start on AsyncTask (a form of Threading) and let it run If it ( the program ) has to callback to the User Interface then use of AsyncTask needs to have the UI element in it that the UI thread will call into If background thread does not need UI to then dont really need AsyncTask but need a service or something instead you can pass object references to some forms of background processing which then can set a var in the AsyncTask based class from background processing or there are callbacks / interfaces in some supplied classes that are meant for that Google I/O 2010 - Writing zippy Android apps http://developer.android.com/videos/index.html#v=Oq05KqjXTvs the guy talks fast by most people but seems rather simple to me -- you fix this stuff now or get blown off the sidewalk later by an NPE when IntentService.onBind (Intent intent) default implementation returns null but you decided not to implement android:maxSdkVersion to do this work you have to keep clear in your mind that a Thread ( from wherever it came ) is an instruction pointer in whatever is driving the code ( which usually is a processor ) then the whole thing becomes remarkably simple surprisingly for those who have not bit the dust on it several times one can do an amazing amount just by making all method calls synchronized or using synchronizaton blocks -- you will see in most accomplished code a style of code design Object lock = new Object() and you just barrier on that On Nov 18, 9:40 pm, Bluemercury <[email protected]> wrote: > Hi there! Sorry for posting here again, but i was hoping if i could try > this sample, you said to put the synchronized in the detach method here: > > void detach() { > *activity=null;* > > } > > in the asynctask, is this correct?but detach() is only called in the > activity and not the in the async task itself, i thought synchronized > methods assumed that they're both launched from 2 different threads....but > in this case the activity(UI thread) calls the detach method like you said, > but the async task doesnt, only the attach method... -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
