AndroidDeferredObject running callbacks in background thread

[korkag]

In Android I want to be able to run callbacks in background thread when resolve called from UI thread and AndroidExecutionScope.BACKGROUND passed in constructor. For example if i run this code in UI thread:

DeferredObject deferred = new DeferredObject();
AndroidDeferredObject androidDeffered = new
AndroidDeferredObject(deferred,AndroidExecutionScope.BACKGROUND);

androidDeffered.then(new DoneCallback(){
// currently run in UI thread, suppose to be running in background thread
});

androidDeffered.resolve("Done");

I don't want to use AndroidDefferedManager, since i want to return to my application Promise without done method and trigger it via resolve function.

[saturnism]

@korkag let me look into that.. but if you always want to do things in the background, you should be able to simply use the DefaultDeferredManager.

[korkag]

No, sometimes i want to be able to run it in background, sometimes in UI thread (android).
There's AndroidDefferedManager which using when(...) with AndroidAsyncTask. I don't want to use "when", instead I want to trigger the Promise via resolve function.

Workaround, i extended from AndroidDeferredObject and did override trigger functions like:

@OverRide
protected void triggerDone(final DoneCallback callback,final D resolved) {
if (determineAndroidExecutionScope(callback) == AndroidExecutionScope.UI || Looper.myLooper() != Looper.getMainLooper()) {
super.triggerDone(callback, resolved);
} else {
new Thread(new Runnable() {
@OverRide
public void run() {
callback.onDone(resolved);
}
}).start();
}
};

Thanks

[saturnism]

gotcha - i think that's a bit more tricky...

[korkag]

Any progress? Do you want me to help? Lets discuss about implementation.
I have another question/feature request - to add cancel functionality/state to the promise. When you cancel promise, no done/fail callbacks are executed. Is it possible to add?

[saturnism]

absolutely would be happy to discuss and help is definitely welcomed.

cancellation is a bit tricky - there was an open issue on this, since the thread will need to handle cancellation properly. when not handled properly, it will cause issues.

[korkag]

Are you using this library in your projects?

On Mon, Aug 11, 2014 at 6:08 PM, Ray Tsang notifications@github.com wrote:

absolutely would be happy to discuss and help is definitely welcomed.

cancellation is a bit tricky - there was an open issue on this, since the
thread will need to handle cancellation properly. when not handled
properly, it will cause issues.

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Reply to this email directly or view it on GitHub
#33 (comment).

[saturnism]

of course =) but it is opensource after all, any contribution for needs/fixes are welcomed.

i don't think that spawning new threads w/o an executor service is a general enough use case. I'm happy that you were able to extend it to fit your need.

it is a bit tricky.