Vulture is an Android library that let you handle asynchronous callbacks properly within Activity/Fragment's life cycle.
Vulture frees you from the hassle with IllegalStateException when coping with FragmentTransaction#commit() after onSaveInstanceState.
Say you have fetchAsynchronously() method to feth a message from a server asynchronously then call doCallback(message) to show DialogFragment like below,
void fetchAsynchronously() {
/* do heavy asynchronous task here */
doCallback("finished!");
}
void doCallback(@NonNull String message) {
FinishDialog.newInstance().show(getSupportFragmentManager(), "TAG");
}You simply annotate your Activity with @ObserveLifecycle, then annotate your methods with @SafeCallback that have to be callbacked safely like below.
Vulture automatically generates a class named SafeMainActivity that has corresponding methods with @SafeCallback annotations at compile time without any Reflection APIs.
@ObserveLifecycle
public class YourActivity extends AppCompatActivity {
void fetchAsynchronously() {
SafeMainActivity.doCallbackSafely("finished!");
}
@SafeCallback
void doCallback(@NonNull String message) {
FinishDialog.newInstance().show(getSupportFragmentManager(), "TAG");
}
}When you call SafeMainActivity.doCallbackSafely(message) after asynchronous task, the actual doCallback(message) is called only within crash free window.
Finally, call register()/unregister() methods to let Vulture know about the safe window.
@Override
protected void onResume() {
super.onResume();
SafeMainActivity.register(this);
}
@Override
protected void onPause() {
SafeMainActivity.unregister();
super.onPause();
}Check sample and generated codes for details.
annotationProcessor 'us.shiroyama.android:vulture-processor:0.3.0'
compile 'us.shiroyama.android:vulture:0.3.0'
Vulture supports argument types for methods annotated with @SafeCallback listed below.
- All primitive types and its boxed types.
- All primitive array types (arrays of boxed types are NOT supported)
- String
- Bundle
- Serializable
- Parcelable
- ParcelableArray
- ParcelableArrayList
Vulture is based on the brilliant idea of PauseHandler discussed at Stack Overflow. Thank you.
Copyright 2017 Fumihiko Shiroyama
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
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distributed under the License is distributed on an "AS IS" BASIS,
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