1 /* 2 * Copyright (C) 2018 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 17 package com.android.layoutlib.bridge.resources; 18 19 import com.android.layoutlib.bridge.bars.Config; 20 import com.android.resources.Density; 21 import com.android.resources.LayoutDirection; 22 23 import java.io.InputStream; 24 25 public class IconLoader { 26 27 private final String mIconName; 28 private final Density mDesiredDensity; 29 private final int mPlatformVersion; 30 private final LayoutDirection mDirection; 31 32 private Density mCurrentDensity; 33 private StringBuilder mCurrentPath; 34 IconLoader(String iconName, Density density, int platformVersion, LayoutDirection direction)35 public IconLoader(String iconName, Density density, int platformVersion, LayoutDirection 36 direction) { 37 mIconName = iconName; 38 mDesiredDensity = density; 39 mPlatformVersion = platformVersion; 40 mDirection = direction; 41 // An upper bound on the length of the path for the icon: /bars/v21/ldrtl-xxxhdpi/ 42 final int iconPathLength = 24; 43 mCurrentPath = new StringBuilder(iconPathLength + iconName.length()); 44 } 45 getIcon()46 public InputStream getIcon() { 47 for (String resourceDir : Config.getResourceDirs(mPlatformVersion)) { 48 mCurrentDensity = null; 49 InputStream stream = getIcon(resourceDir); 50 if (stream != null) { 51 return stream; 52 } 53 } 54 return null; 55 } 56 57 /** 58 * Should only be called after {@link #getIcon()}. Returns the density of the icon, if found by 59 * {@code getIcon()}. If no icon was found, then the return value has no meaning. 60 */ getDensity()61 public Density getDensity() { 62 return mCurrentDensity; 63 } 64 65 /** 66 * Should only be called after {@link #getIcon()}. Returns the path to the icon, if found by 67 * {@code getIcon()}. If no icon was found, then the return value has no meaning. 68 */ getPath()69 public String getPath() { 70 return mCurrentPath.toString(); 71 } 72 73 /** 74 * Search for icon in the resource directory. This iterates over all densities. 75 * If a match is found, mCurrentDensity will be set to the icon's density. 76 */ getIcon(String resourceDir)77 private InputStream getIcon(String resourceDir) { 78 // First check for the desired density. 79 InputStream stream = getIcon(resourceDir, mDesiredDensity); 80 if (stream != null) { 81 mCurrentDensity = mDesiredDensity; 82 return stream; 83 } 84 // Didn't find in the desired density. Search in all. 85 for (Density density : Density.values()) { 86 if (density == mDesiredDensity) { 87 // Skip the desired density since it's already been checked. 88 continue; 89 } 90 stream = getIcon(resourceDir, density); 91 if (stream != null) { 92 mCurrentDensity = density; 93 return stream; 94 } 95 } 96 return null; 97 } 98 99 /** 100 * Returns the icon for given density present in the given resource directory, taking layout 101 * direction into consideration. 102 */ getIcon(String resourceDir, Density density)103 private InputStream getIcon(String resourceDir, Density density) { 104 mCurrentPath.setLength(0); 105 // Currently we don't have any LTR only resources and hence the check is skipped. If they 106 // are ever added, change to: 107 // if (mDirection == LayoutDirection.RTL || mDirection == LayoutDirection.LTR) { 108 if (mDirection == LayoutDirection.RTL) { 109 mCurrentPath.append(resourceDir) 110 .append(mDirection.getResourceValue()) 111 .append('-') 112 .append(density.getResourceValue()) 113 .append('/') 114 .append(mIconName); 115 InputStream stream = getClass().getResourceAsStream(mCurrentPath.toString()); 116 if (stream != null) { 117 return stream; 118 } 119 mCurrentPath.setLength(0); 120 } 121 mCurrentPath.append(resourceDir) 122 .append(density.getResourceValue()) 123 .append('/') 124 .append(mIconName); 125 return getClass().getResourceAsStream(mCurrentPath.toString()); 126 } 127 } 128