android.support.v4.view.ScaleGestureDetectorCompat Maven / Gradle / Ivy
/*
* Copyright (C) 2013 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 android.support.v4.view;
/**
* Helper for accessing features in ScaleGestureDetector introduced
* after API level 19 (KitKat) in a backwards compatible fashion.
*/
public class ScaleGestureDetectorCompat {
static final ScaleGestureDetectorImpl IMPL;
interface ScaleGestureDetectorImpl {
public void setQuickScaleEnabled(Object o, boolean enabled);
public boolean isQuickScaleEnabled(Object o);
}
private static class BaseScaleGestureDetectorImpl implements ScaleGestureDetectorImpl {
@Override
public void setQuickScaleEnabled(Object o, boolean enabled) {
// Intentionally blank
}
@Override
public boolean isQuickScaleEnabled(Object o) {
return false;
}
}
private static class ScaleGestureDetectorCompatKitKatImpl implements ScaleGestureDetectorImpl {
@Override
public void setQuickScaleEnabled(Object o, boolean enabled) {
ScaleGestureDetectorCompatKitKat.setQuickScaleEnabled(o, enabled);
}
@Override
public boolean isQuickScaleEnabled(Object o) {
return ScaleGestureDetectorCompatKitKat.isQuickScaleEnabled(o);
}
}
static {
final int version = android.os.Build.VERSION.SDK_INT;
if (version >= 19) { // KitKat
IMPL = new ScaleGestureDetectorCompatKitKatImpl();
} else {
IMPL = new BaseScaleGestureDetectorImpl();
}
}
private ScaleGestureDetectorCompat() {}
/**
* Set whether the associated OnScaleGestureListener should receive onScale
* callbacks when the user performs a doubleTap followed by a swipe. Note that this is enabled
* by default if the app targets API 19 and newer.
* @param enabled true to enable quick scaling, false to disable
*/
public static void setQuickScaleEnabled(Object scaleGestureDetector, boolean enabled) {
IMPL.setQuickScaleEnabled(scaleGestureDetector, enabled);
}
/**
* Return whether the quick scale gesture, in which the user performs a double tap followed by a
* swipe, should perform scaling. See setQuickScaleEnabled(Object, boolean).
*/
public static boolean isQuickScaleEnabled(Object scaleGestureDetector) {
return IMPL.isQuickScaleEnabled(scaleGestureDetector); // KitKat
}
}