ViewUtilsApi19.java
/*
* Copyright (C) 2017 The Android Open Source Project
*
* 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 androidx.transition;
import android.annotation.SuppressLint;
import android.view.View;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
@RequiresApi(19)
class ViewUtilsApi19 extends ViewUtilsBase {
/**
* False when linking of the hidden set[get]TransitionAlpha method has previously failed.
*/
private static boolean sTryHiddenTransitionAlpha = true;
@Override
@SuppressLint("NewApi") // Lint doesn't know about the hidden method.
public void setTransitionAlpha(@NonNull View view, float alpha) {
if (sTryHiddenTransitionAlpha) {
// Since this was an @hide method made public, we can link directly against it with
// a try/catch for its absence instead of doing the same through reflection.
try {
view.setTransitionAlpha(alpha);
return;
} catch (NoSuchMethodError e) {
sTryHiddenTransitionAlpha = false;
}
}
view.setAlpha(alpha);
}
@Override
@SuppressLint("NewApi") // Lint doesn't know about the hidden method.
public float getTransitionAlpha(@NonNull View view) {
if (sTryHiddenTransitionAlpha) {
// Since this was an @hide method made public, we can link directly against it with
// a try/catch for its absence instead of doing the same through reflection.
try {
return view.getTransitionAlpha();
} catch (NoSuchMethodError e) {
sTryHiddenTransitionAlpha = false;
}
}
return view.getAlpha();
}
@Override
public void saveNonTransitionAlpha(@NonNull View view) {
// Do nothing
}
@Override
public void clearNonTransitionAlpha(@NonNull View view) {
// Do nothing
}
}