I am trying to use an SDK that seems to need to create a handler into my service.
A error message appeared saying that I can't create handler if the thread has not called Looper.prepare(), so I do call Looper.prepare() and this problem disappear.
However, this service need to start an activity after a while, and this Looper.prepare() seems to be messing with it, as the first UI function crash saying that it cannot be called from a non-ui thread.
I am a bit confused about why this is happening, and the research I made on thread and looper didn't help me. I get why we cannot create a handler if a looper does not exist on the thread, but not why creating a looper prevent me from using the ui thread afterward.
Below my code simplified :
public class MyService extends Service implement SDKCallback{
...
void callSDK(){
Looper.prepare();
SDK.run(); //Does thing I don't know about
}
@Override
SDKCallback(){
startActivity(new Intent(this, MyActivity.class);
}
}
You dont have to call Looper.prepare(). Try this code to create Handler,
new Handler(Looper.getMainLooper()) {
@Override
public void handleMessage(Message message) {
}
};
If you put Looper.prepare() in your worker thread, it will solve your first crash problem [the thread has not called Looper.prepare()]. But its not in UI thread, so you cant start next Activity.
What this above code does is, it creates the Handler in UI thread. So you can start next Activity.
Edit: Try this.
@Override
SDKCallback(){
new Handler(Looper.getMainLooper()) {
@Override
public void handleMessage(Message message) {
startActivity(new Intent(MyService.this, MyActivity.class));
}
};
}