1 /* 2 * Copyright (C) 2006 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 android.graphics.drawable; 18 19 import org.xmlpull.v1.XmlPullParser; 20 import org.xmlpull.v1.XmlPullParserException; 21 22 import java.io.IOException; 23 import java.util.Arrays; 24 25 import android.content.res.Resources; 26 import android.content.res.TypedArray; 27 import android.util.AttributeSet; 28 import android.util.StateSet; 29 30 /** 31 * Lets you assign a number of graphic images to a single Drawable and swap out the visible item by a string 32 * ID value. 33 * <p/> 34 * <p>It can be defined in an XML file with the <code><selector></code> element. 35 * Each state Drawable is defined in a nested <code><item></code> element. For more 36 * information, see the guide to <a 37 * href="{@docRoot}guide/topics/resources/drawable-resource.html">Drawable Resources</a>.</p> 38 * 39 * @attr ref android.R.styleable#StateListDrawable_visible 40 * @attr ref android.R.styleable#StateListDrawable_variablePadding 41 * @attr ref android.R.styleable#StateListDrawable_constantSize 42 * @attr ref android.R.styleable#DrawableStates_state_focused 43 * @attr ref android.R.styleable#DrawableStates_state_window_focused 44 * @attr ref android.R.styleable#DrawableStates_state_enabled 45 * @attr ref android.R.styleable#DrawableStates_state_checkable 46 * @attr ref android.R.styleable#DrawableStates_state_checked 47 * @attr ref android.R.styleable#DrawableStates_state_selected 48 * @attr ref android.R.styleable#DrawableStates_state_activated 49 * @attr ref android.R.styleable#DrawableStates_state_active 50 * @attr ref android.R.styleable#DrawableStates_state_single 51 * @attr ref android.R.styleable#DrawableStates_state_first 52 * @attr ref android.R.styleable#DrawableStates_state_middle 53 * @attr ref android.R.styleable#DrawableStates_state_last 54 * @attr ref android.R.styleable#DrawableStates_state_pressed 55 */ 56 public class StateListDrawable extends DrawableContainer { 57 private static final boolean DEBUG = false; 58 private static final String TAG = "StateListDrawable"; 59 60 /** 61 * To be proper, we should have a getter for dither (and alpha, etc.) 62 * so that proxy classes like this can save/restore their delegates' 63 * values, but we don't have getters. Since we do have setters 64 * (e.g. setDither), which this proxy forwards on, we have to have some 65 * default/initial setting. 66 * 67 * The initial setting for dither is now true, since it almost always seems 68 * to improve the quality at negligible cost. 69 */ 70 private static final boolean DEFAULT_DITHER = true; 71 private final StateListState mStateListState; 72 private boolean mMutated; 73 74 public StateListDrawable() { 75 this(null, null); 76 } 77 78 /** 79 * Add a new image/string ID to the set of images. 80 * 81 * @param stateSet - An array of resource Ids to associate with the image. 82 * Switch to this image by calling setState(). 83 * @param drawable -The image to show. 84 */ 85 public void addState(int[] stateSet, Drawable drawable) { 86 if (drawable != null) { 87 mStateListState.addStateSet(stateSet, drawable); 88 // in case the new state matches our current state... 89 onStateChange(getState()); 90 } 91 } 92 93 @Override 94 public boolean isStateful() { 95 return true; 96 } 97 98 @Override 99 protected boolean onStateChange(int[] stateSet) { 100 int idx = mStateListState.indexOfStateSet(stateSet); 101 if (DEBUG) android.util.Log.i(TAG, "onStateChange " + this + " states " 102 + Arrays.toString(stateSet) + " found " + idx); 103 if (idx < 0) { 104 idx = mStateListState.indexOfStateSet(StateSet.WILD_CARD); 105 } 106 if (selectDrawable(idx)) { 107 return true; 108 } 109 return super.onStateChange(stateSet); 110 } 111 112 @Override 113 public void inflate(Resources r, XmlPullParser parser, 114 AttributeSet attrs) 115 throws XmlPullParserException, IOException { 116 117 TypedArray a = r.obtainAttributes(attrs, 118 com.android.internal.R.styleable.StateListDrawable); 119 120 super.inflateWithAttributes(r, parser, a, 121 com.android.internal.R.styleable.StateListDrawable_visible); 122 123 mStateListState.setVariablePadding(a.getBoolean( 124 com.android.internal.R.styleable.StateListDrawable_variablePadding, false)); 125 mStateListState.setConstantSize(a.getBoolean( 126 com.android.internal.R.styleable.StateListDrawable_constantSize, false)); 127 mStateListState.setEnterFadeDuration(a.getInt( 128 com.android.internal.R.styleable.StateListDrawable_enterFadeDuration, 0)); 129 mStateListState.setExitFadeDuration(a.getInt( 130 com.android.internal.R.styleable.StateListDrawable_exitFadeDuration, 0)); 131 132 setDither(a.getBoolean(com.android.internal.R.styleable.StateListDrawable_dither, 133 DEFAULT_DITHER)); 134 135 setAutoMirrored(a.getBoolean( 136 com.android.internal.R.styleable.StateListDrawable_autoMirrored, false)); 137 138 a.recycle(); 139 140 int type; 141 142 final int innerDepth = parser.getDepth() + 1; 143 int depth; 144 while ((type = parser.next()) != XmlPullParser.END_DOCUMENT 145 && ((depth = parser.getDepth()) >= innerDepth 146 || type != XmlPullParser.END_TAG)) { 147 if (type != XmlPullParser.START_TAG) { 148 continue; 149 } 150 151 if (depth > innerDepth || !parser.getName().equals("item")) { 152 continue; 153 } 154 155 int drawableRes = 0; 156 157 int i; 158 int j = 0; 159 final int numAttrs = attrs.getAttributeCount(); 160 int[] states = new int[numAttrs]; 161 for (i = 0; i < numAttrs; i++) { 162 final int stateResId = attrs.getAttributeNameResource(i); 163 if (stateResId == 0) break; 164 if (stateResId == com.android.internal.R.attr.drawable) { 165 drawableRes = attrs.getAttributeResourceValue(i, 0); 166 } else { 167 states[j++] = attrs.getAttributeBooleanValue(i, false) 168 ? stateResId 169 : -stateResId; 170 } 171 } 172 states = StateSet.trimStateSet(states, j); 173 174 Drawable dr; 175 if (drawableRes != 0) { 176 dr = r.getDrawable(drawableRes); 177 } else { 178 while ((type = parser.next()) == XmlPullParser.TEXT) { 179 } 180 if (type != XmlPullParser.START_TAG) { 181 throw new XmlPullParserException( 182 parser.getPositionDescription() 183 + ": <item> tag requires a 'drawable' attribute or " 184 + "child tag defining a drawable"); 185 } 186 dr = Drawable.createFromXmlInner(r, parser, attrs); 187 } 188 189 mStateListState.addStateSet(states, dr); 190 } 191 192 onStateChange(getState()); 193 } 194 195 StateListState getStateListState() { 196 return mStateListState; 197 } 198 199 /** 200 * Gets the number of states contained in this drawable. 201 * 202 * @return The number of states contained in this drawable. 203 * @hide pending API council 204 * @see #getStateSet(int) 205 * @see #getStateDrawable(int) 206 */ 207 public int getStateCount() { 208 return mStateListState.getChildCount(); 209 } 210 211 /** 212 * Gets the state set at an index. 213 * 214 * @param index The index of the state set. 215 * @return The state set at the index. 216 * @hide pending API council 217 * @see #getStateCount() 218 * @see #getStateDrawable(int) 219 */ 220 public int[] getStateSet(int index) { 221 return mStateListState.mStateSets[index]; 222 } 223 224 /** 225 * Gets the drawable at an index. 226 * 227 * @param index The index of the drawable. 228 * @return The drawable at the index. 229 * @hide pending API council 230 * @see #getStateCount() 231 * @see #getStateSet(int) 232 */ 233 public Drawable getStateDrawable(int index) { 234 return mStateListState.getChild(index); 235 } 236 237 /** 238 * Gets the index of the drawable with the provided state set. 239 * 240 * @param stateSet the state set to look up 241 * @return the index of the provided state set, or -1 if not found 242 * @hide pending API council 243 * @see #getStateDrawable(int) 244 * @see #getStateSet(int) 245 */ 246 public int getStateDrawableIndex(int[] stateSet) { 247 return mStateListState.indexOfStateSet(stateSet); 248 } 249 250 @Override 251 public Drawable mutate() { 252 if (!mMutated && super.mutate() == this) { 253 final int[][] sets = mStateListState.mStateSets; 254 final int count = sets.length; 255 mStateListState.mStateSets = new int[count][]; 256 for (int i = 0; i < count; i++) { 257 final int[] set = sets[i]; 258 if (set != null) { 259 mStateListState.mStateSets[i] = set.clone(); 260 } 261 } 262 mMutated = true; 263 } 264 return this; 265 } 266 267 /** @hide */ 268 @Override 269 public void setLayoutDirection(int layoutDirection) { 270 super.setLayoutDirection(layoutDirection); 271 272 // Let the container handle setting its own layout direction. Otherwise, 273 // we're accessing potentially unused states. 274 mStateListState.setLayoutDirection(layoutDirection); 275 } 276 277 static final class StateListState extends DrawableContainerState { 278 int[][] mStateSets; 279 280 StateListState(StateListState orig, StateListDrawable owner, Resources res) { 281 super(orig, owner, res); 282 283 if (orig != null) { 284 mStateSets = Arrays.copyOf(orig.mStateSets, orig.mStateSets.length); 285 } else { 286 mStateSets = new int[getCapacity()][]; 287 } 288 } 289 290 int addStateSet(int[] stateSet, Drawable drawable) { 291 final int pos = addChild(drawable); 292 mStateSets[pos] = stateSet; 293 return pos; 294 } 295 296 private int indexOfStateSet(int[] stateSet) { 297 final int[][] stateSets = mStateSets; 298 final int N = getChildCount(); 299 for (int i = 0; i < N; i++) { 300 if (StateSet.stateSetMatches(stateSets[i], stateSet)) { 301 return i; 302 } 303 } 304 return -1; 305 } 306 307 @Override 308 public Drawable newDrawable() { 309 return new StateListDrawable(this, null); 310 } 311 312 @Override 313 public Drawable newDrawable(Resources res) { 314 return new StateListDrawable(this, res); 315 } 316 317 @Override 318 public void growArray(int oldSize, int newSize) { 319 super.growArray(oldSize, newSize); 320 final int[][] newStateSets = new int[newSize][]; 321 System.arraycopy(mStateSets, 0, newStateSets, 0, oldSize); 322 mStateSets = newStateSets; 323 } 324 } 325 326 private StateListDrawable(StateListState state, Resources res) { 327 StateListState as = new StateListState(state, this, res); 328 mStateListState = as; 329 setConstantState(as); 330 onStateChange(getState()); 331 } 332 } 333 334
