-
Notifications
You must be signed in to change notification settings - Fork 24
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Correctly process tracking state changes
- Loading branch information
1 parent
9f2cf03
commit dc023c7
Showing
6 changed files
with
121 additions
and
43 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,72 @@ | ||
| /* | ||
| * Copyright 2017 Google Inc. | ||
| * | ||
| * 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 | ||
| * | ||
| * Unless required by applicable law or agreed to in writing, software | ||
| * distributed under the License is distributed on an "AS IS" BASIS, | ||
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
| * See the License for the specific language governing permissions and | ||
| * limitations under the License. | ||
| */ | ||
|
|
||
| package mobi.maptrek.util; | ||
|
|
||
| import android.util.Log; | ||
|
|
||
| import androidx.annotation.MainThread; | ||
| import androidx.annotation.NonNull; | ||
| import androidx.annotation.Nullable; | ||
| import androidx.lifecycle.LifecycleOwner; | ||
| import androidx.lifecycle.MutableLiveData; | ||
| import androidx.lifecycle.Observer; | ||
|
|
||
| import java.util.concurrent.atomic.AtomicBoolean; | ||
|
|
||
| /** | ||
| * A lifecycle-aware observable that sends only new updates after subscription, used for events like | ||
| * navigation and Snackbar messages. | ||
| * <p> | ||
| * This avoids a common problem with events: on configuration change (like rotation) an update | ||
| * can be emitted if the observer is active. This LiveData only calls the observable if there's an | ||
| * explicit call to setValue() or call(). | ||
| * <p> | ||
| * Note that only one observer is going to be notified of changes. | ||
| */ | ||
| public class SingleLiveEvent<T> extends MutableLiveData<T> { | ||
|
|
||
| private static final String TAG = "SingleLiveEvent"; | ||
|
|
||
| private final AtomicBoolean mPending = new AtomicBoolean(false); | ||
|
|
||
| @MainThread | ||
| public void observe(@NonNull LifecycleOwner owner, @NonNull Observer<? super T> observer) { | ||
| if (hasActiveObservers()) { | ||
| Log.w(TAG, "Multiple observers registered but only one will be notified of changes."); | ||
| } | ||
| // Observe the internal MutableLiveData | ||
| super.observe(owner, t -> { | ||
| if (mPending.compareAndSet(true, false)) { | ||
| observer.onChanged(t); | ||
| } | ||
| }); | ||
| } | ||
|
|
||
| @MainThread | ||
| public void setValue(@Nullable T value) { | ||
| mPending.set(true); | ||
| super.setValue(value); | ||
| } | ||
|
|
||
| /** | ||
| * Used for cases where T is Void, to make calls cleaner. | ||
| */ | ||
| @MainThread | ||
| public void call() { | ||
| setValue(null); | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters