1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.support.v4.view; 18 19import android.view.ViewConfiguration; 20 21/** 22 * Helper for accessing features in {@link ViewConfiguration} 23 * introduced after API level 4 in a backwards compatible fashion. 24 */ 25public class ViewConfigurationCompat { 26 /** 27 * Interface for the full API. 28 */ 29 interface ViewConfigurationVersionImpl { 30 public int getScaledPagingTouchSlop(ViewConfiguration config); 31 } 32 33 /** 34 * Interface implementation that doesn't use anything about v4 APIs. 35 */ 36 static class BaseViewConfigurationVersionImpl implements ViewConfigurationVersionImpl { 37 @Override 38 public int getScaledPagingTouchSlop(ViewConfiguration config) { 39 return config.getScaledTouchSlop(); 40 } 41 } 42 43 /** 44 * Interface implementation for devices with at least v11 APIs. 45 */ 46 static class FroyoViewConfigurationVersionImpl implements ViewConfigurationVersionImpl { 47 @Override 48 public int getScaledPagingTouchSlop(ViewConfiguration config) { 49 return ViewConfigurationCompatFroyo.getScaledPagingTouchSlop(config); 50 } 51 } 52 53 /** 54 * Select the correct implementation to use for the current platform. 55 */ 56 static final ViewConfigurationVersionImpl IMPL; 57 static { 58 if (android.os.Build.VERSION.SDK_INT >= 11) { 59 IMPL = new FroyoViewConfigurationVersionImpl(); 60 } else { 61 IMPL = new BaseViewConfigurationVersionImpl(); 62 } 63 } 64 65 // ------------------------------------------------------------------- 66 67 /** 68 * Call {@link ViewConfiguration#getScaledPagingTouchSlop()}. 69 * If running on a pre-{@link android.os.Build.VERSION_CODES#FROYO} device, 70 * returns {@link ViewConfiguration#getScaledTouchSlop()}. 71 */ 72 public static int getScaledPagingTouchSlop(ViewConfiguration config) { 73 return IMPL.getScaledPagingTouchSlop(config); 74 } 75} 76