ViewConfigurationCompat.java revision eedc67283a5a49dce86c625e54596dfdea9465a7 
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 newer features in ViewConfiguration.
23 */
24public class ViewConfigurationCompat {
25    /**
26     * Interface for the full API.
27     */
28    interface ViewConfigurationVersionImpl {
29        public int getScaledPagingTouchSlop(ViewConfiguration config);
30    }
31
32    /**
33     * Interface implementation that doesn't use anything about v4 APIs.
34     */
35    static class BaseViewConfigurationVersionImpl implements ViewConfigurationVersionImpl {
36        @Override
37        public int getScaledPagingTouchSlop(ViewConfiguration config) {
38            return config.getScaledTouchSlop();
39        }
40    }
41
42    /**
43     * Interface implementation for devices with at least v11 APIs.
44     */
45    static class FroyoViewConfigurationVersionImpl implements ViewConfigurationVersionImpl {
46        @Override
47        public int getScaledPagingTouchSlop(ViewConfiguration config) {
48            return ViewConfigurationCompatFroyo.getScaledPagingTouchSlop(config);
49        }
50    }
51
52    /**
53     * Select the correct implementation to use for the current platform.
54     */
55    static final ViewConfigurationVersionImpl IMPL;
56    static {
57        if (android.os.Build.VERSION.SDK_INT >= 11) {
58            IMPL = new FroyoViewConfigurationVersionImpl();
59        } else {
60            IMPL = new BaseViewConfigurationVersionImpl();
61        }
62    }
63
64    // -------------------------------------------------------------------
65
66    /**
67     * Call {@link ViewConfiguration#getScaledPagingTouchSlop()}.
68     * If running on a pre-{@android.os.Build.VERSION_CODES#FROYO} device,
69     * returns {@link ViewConfiguration#getScaledTouchSlop()}.
70     */
71    public static int getScaledPagingTouchSlop(ViewConfiguration config) {
72        return IMPL.getScaledPagingTouchSlop(config);
73    }
74}
75