1/* 2 * Copyright (C) 2015 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.design.widget; 18 19import android.graphics.drawable.Drawable; 20import android.graphics.drawable.DrawableContainer; 21import android.os.Build; 22import android.util.Log; 23 24import java.lang.reflect.Field; 25import java.lang.reflect.Method; 26 27/** 28 * Caution. Gross hacks ahead. 29 */ 30class DrawableUtils { 31 32 private static final String LOG_TAG = "DrawableUtils"; 33 34 private static Method sSetConstantStateMethod; 35 private static boolean sSetConstantStateMethodFetched; 36 37 private static Field sDrawableContainerStateField; 38 private static boolean sDrawableContainerStateFieldFetched; 39 40 private DrawableUtils() {} 41 42 static boolean setContainerConstantState(DrawableContainer drawable, 43 Drawable.ConstantState constantState) { 44 if (Build.VERSION.SDK_INT >= 9) { 45 // We can use getDeclaredMethod() on v9+ 46 return setContainerConstantStateV9(drawable, constantState); 47 } else { 48 // Else we'll just have to set the field directly 49 return setContainerConstantStateV7(drawable, constantState); 50 } 51 } 52 53 private static boolean setContainerConstantStateV9(DrawableContainer drawable, 54 Drawable.ConstantState constantState) { 55 if (!sSetConstantStateMethodFetched) { 56 try { 57 sSetConstantStateMethod = DrawableContainer.class.getDeclaredMethod( 58 "setConstantState", DrawableContainer.DrawableContainerState.class); 59 sSetConstantStateMethod.setAccessible(true); 60 } catch (NoSuchMethodException e) { 61 Log.e(LOG_TAG, "Could not fetch setConstantState(). Oh well."); 62 } 63 sSetConstantStateMethodFetched = true; 64 } 65 if (sSetConstantStateMethod != null) { 66 try { 67 sSetConstantStateMethod.invoke(drawable, constantState); 68 return true; 69 } catch (Exception e) { 70 Log.e(LOG_TAG, "Could not invoke setConstantState(). Oh well."); 71 } 72 } 73 return false; 74 } 75 76 private static boolean setContainerConstantStateV7(DrawableContainer drawable, 77 Drawable.ConstantState constantState) { 78 if (!sDrawableContainerStateFieldFetched) { 79 try { 80 sDrawableContainerStateField = DrawableContainer.class 81 .getDeclaredField("mDrawableContainerStateField"); 82 sDrawableContainerStateField.setAccessible(true); 83 } catch (NoSuchFieldException e) { 84 Log.e(LOG_TAG, "Could not fetch mDrawableContainerStateField. Oh well."); 85 } 86 sDrawableContainerStateFieldFetched = true; 87 } 88 if (sDrawableContainerStateField != null) { 89 try { 90 sDrawableContainerStateField.set(drawable, constantState); 91 return true; 92 } catch (Exception e) { 93 Log.e(LOG_TAG, "Could not set mDrawableContainerStateField. Oh well."); 94 } 95 } 96 return false; 97 } 98 99} 100