I have an activity that load data from internet and it works fine except that o have to double click back button to finish it. I also noticed that in the activities that don't connect to internet back button works from first click. and when debugging it i found that fragment manager callback is handling first click
FragmentManager.this.handleOnBackPressed();
from source
void handleOnBackPressed() {
// First, execute any pending actions to make sure we're in an
// up to date view of the world just in case anyone is queuing
// up transactions that change the back stack then immediately
// calling onBackPressed()
execPendingActions();
if (mOnBackPressedCallback.isEnabled()) {
// We still have a back stack, so we can pop
popBackStackImmediate();
} else {
// Sigh. Due to FragmentManager's asynchronicity, we can
// get into cases where we *think* we can handle the back
// button but because of frame perfect dispatch, we fell
// on our face. Since our callback is disabled, we can
// re-trigger the onBackPressed() to dispatch to the next
// enabled callback
mOnBackPressedDispatcher.onBackPressed();
}
}
although i don't use fragment