DrawableCompat.java revision ac00a989afc2f1c559fc33174f481a0a0ef5b3d8 
1/*
2 * Copyright (C) 2013 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.graphics.drawable;
18
19import android.graphics.drawable.Drawable;
20import android.os.Build;
21
22/**
23 * Helper for accessing features in {@link android.graphics.drawable.Drawable}
24 * introduced after API level 4 in a backwards compatible fashion.
25 */
26public class DrawableCompat {
27    /**
28     * Interface for the full API.
29     */
30    interface DrawableImpl {
31        void jumpToCurrentState(Drawable drawable);
32        void setAutoMirrored(Drawable drawable, boolean mirrored);
33        boolean isAutoMirrored(Drawable drawable);
34        void setHotspot(Drawable drawable, float x, float y);
35        void setHotspotBounds(Drawable drawable, int left, int top, int right, int bottom);
36    }
37
38    /**
39     * Interface implementation that doesn't use anything about v4 APIs.
40     */
41    static class BaseDrawableImpl implements DrawableImpl {
42        @Override
43        public void jumpToCurrentState(Drawable drawable) {
44        }
45
46        @Override
47        public void setAutoMirrored(Drawable drawable, boolean mirrored) {
48        }
49
50        @Override
51        public boolean isAutoMirrored(Drawable drawable) {
52            return false;
53        }
54
55        @Override
56        public void setHotspot(Drawable drawable, float x, float y) {
57        }
58
59        @Override
60        public void setHotspotBounds(Drawable drawable, int left, int top, int right, int bottom) {
61        }
62    }
63
64    /**
65     * Interface implementation for devices with at least v11 APIs.
66     */
67    static class HoneycombDrawableImpl extends BaseDrawableImpl {
68        @Override
69        public void jumpToCurrentState(Drawable drawable) {
70            DrawableCompatHoneycomb.jumpToCurrentState(drawable);
71        }
72    }
73
74    /**
75     * Interface implementation for devices with at least KitKat APIs.
76     */
77    static class KitKatDrawableImpl extends HoneycombDrawableImpl {
78        @Override
79        public void setAutoMirrored(Drawable drawable, boolean mirrored) {
80            DrawableCompatKitKat.setAutoMirrored(drawable, mirrored);
81        }
82
83        @Override
84        public boolean isAutoMirrored(Drawable drawable) {
85            return DrawableCompatKitKat.isAutoMirrored(drawable);
86        }
87    }
88
89    /**
90     * Interface implementation for devices with at least L APIs.
91     */
92    static class LDrawableImpl extends KitKatDrawableImpl {
93        @Override
94        public void setHotspot(Drawable drawable, float x, float y) {
95            DrawableCompatL.setHotspot(drawable, x, y);
96        }
97
98        @Override
99        public void setHotspotBounds(Drawable drawable, int left, int top, int right, int bottom) {
100            DrawableCompatL.setHotspotBounds(drawable, left, top, right, bottom);
101        }
102    }
103
104    /**
105     * Select the correct implementation to use for the current platform.
106     */
107    static final DrawableImpl IMPL;
108    static {
109        final int version = android.os.Build.VERSION.SDK_INT;
110        if (version >= 21 || Build.VERSION.CODENAME.equals("L")) {
111            IMPL = new LDrawableImpl();
112        } else if (version >= 19) {
113            IMPL = new KitKatDrawableImpl();
114        } else if (version >= 11) {
115            IMPL = new HoneycombDrawableImpl();
116        } else {
117            IMPL = new BaseDrawableImpl();
118        }
119    }
120
121    /**
122     * Call {@link Drawable#jumpToCurrentState() Drawable.jumpToCurrentState()}.
123     * <p>
124     * If running on a pre-{@link android.os.Build.VERSION_CODES#HONEYCOMB}
125     * device this method does nothing.
126     *
127     * @param drawable The Drawable against which to invoke the method.
128     */
129    public static void jumpToCurrentState(Drawable drawable) {
130        IMPL.jumpToCurrentState(drawable);
131    }
132
133    /**
134     * Set whether this Drawable is automatically mirrored when its layout
135     * direction is RTL (right-to left). See
136     * {@link android.util.LayoutDirection}.
137     * <p>
138     * If running on a pre-{@link android.os.Build.VERSION_CODES#KITKAT} device
139     * this method does nothing.
140     *
141     * @param drawable The Drawable against which to invoke the method.
142     * @param mirrored Set to true if the Drawable should be mirrored, false if
143     *            not.
144     */
145    public static void setAutoMirrored(Drawable drawable, boolean mirrored) {
146        IMPL.setAutoMirrored(drawable, mirrored);
147    }
148
149    /**
150     * Tells if this Drawable will be automatically mirrored when its layout
151     * direction is RTL right-to-left. See {@link android.util.LayoutDirection}.
152     * <p>
153     * If running on a pre-{@link android.os.Build.VERSION_CODES#KITKAT} device
154     * this method returns false.
155     *
156     * @param drawable The Drawable against which to invoke the method.
157     * @return boolean Returns true if this Drawable will be automatically
158     *         mirrored.
159     */
160    public static boolean isAutoMirrored(Drawable drawable) {
161        return IMPL.isAutoMirrored(drawable);
162    }
163
164    /**
165     * Specifies the hotspot's location within the drawable.
166     *
167     * @param drawable The Drawable against which to invoke the method.
168     * @param x The X coordinate of the center of the hotspot
169     * @param y The Y coordinate of the center of the hotspot
170     */
171    public static void setHotspot(Drawable drawable, float x, float y) {
172        IMPL.setHotspot(drawable, x, y);
173    }
174
175    /**
176     * Sets the bounds to which the hotspot is constrained, if they should be
177     * different from the drawable bounds.
178     *
179     * @param drawable The Drawable against which to invoke the method.
180     */
181    public static void setHotspotBounds(Drawable drawable, int left, int top,
182            int right, int bottom) {
183        IMPL.setHotspotBounds(drawable, left, top, right, bottom);
184    }
185}
186