ScaleDrawable.java revision cda212d79d449468384cc7744878b8c99984059c
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 17package android.graphics.drawable; 18 19import org.xmlpull.v1.XmlPullParser; 20import org.xmlpull.v1.XmlPullParserException; 21 22import android.content.res.Resources; 23import android.content.res.TypedArray; 24import android.content.res.Resources.Theme; 25import android.graphics.*; 26import android.view.Gravity; 27import android.util.AttributeSet; 28 29import java.io.IOException; 30 31/** 32 * A Drawable that changes the size of another Drawable based on its current 33 * level value. You can control how much the child Drawable changes in width 34 * and height based on the level, as well as a gravity to control where it is 35 * placed in its overall container. Most often used to implement things like 36 * progress bars. 37 * 38 * <p>It can be defined in an XML file with the <code><scale></code> element. For more 39 * information, see the guide to <a 40 * href="{@docRoot}guide/topics/resources/drawable-resource.html">Drawable Resources</a>.</p> 41 * 42 * @attr ref android.R.styleable#ScaleDrawable_scaleWidth 43 * @attr ref android.R.styleable#ScaleDrawable_scaleHeight 44 * @attr ref android.R.styleable#ScaleDrawable_scaleGravity 45 * @attr ref android.R.styleable#ScaleDrawable_drawable 46 */ 47public class ScaleDrawable extends Drawable implements Drawable.Callback { 48 private ScaleState mScaleState; 49 private boolean mMutated; 50 private final Rect mTmpRect = new Rect(); 51 52 ScaleDrawable() { 53 this(null, null); 54 } 55 56 public ScaleDrawable(Drawable drawable, int gravity, float scaleWidth, float scaleHeight) { 57 this(null, null); 58 59 mScaleState.mDrawable = drawable; 60 mScaleState.mGravity = gravity; 61 mScaleState.mScaleWidth = scaleWidth; 62 mScaleState.mScaleHeight = scaleHeight; 63 64 if (drawable != null) { 65 drawable.setCallback(this); 66 } 67 } 68 69 /** 70 * Returns the drawable scaled by this ScaleDrawable. 71 */ 72 public Drawable getDrawable() { 73 return mScaleState.mDrawable; 74 } 75 76 private static float getPercent(TypedArray a, int name) { 77 String s = a.getString(name); 78 if (s != null) { 79 if (s.endsWith("%")) { 80 String f = s.substring(0, s.length() - 1); 81 return Float.parseFloat(f) / 100.0f; 82 } 83 } 84 return -1; 85 } 86 87 @Override 88 public void inflate(Resources r, XmlPullParser parser, AttributeSet attrs, Theme theme) 89 throws XmlPullParserException, IOException { 90 super.inflate(r, parser, attrs, theme); 91 92 int type; 93 94 TypedArray a = r.obtainAttributes(attrs, com.android.internal.R.styleable.ScaleDrawable); 95 96 float sw = getPercent(a, com.android.internal.R.styleable.ScaleDrawable_scaleWidth); 97 float sh = getPercent(a, com.android.internal.R.styleable.ScaleDrawable_scaleHeight); 98 int g = a.getInt(com.android.internal.R.styleable.ScaleDrawable_scaleGravity, Gravity.LEFT); 99 boolean min = a.getBoolean( 100 com.android.internal.R.styleable.ScaleDrawable_useIntrinsicSizeAsMinimum, false); 101 Drawable dr = a.getDrawable(com.android.internal.R.styleable.ScaleDrawable_drawable); 102 103 a.recycle(); 104 105 final int outerDepth = parser.getDepth(); 106 while ((type = parser.next()) != XmlPullParser.END_DOCUMENT 107 && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) { 108 if (type != XmlPullParser.START_TAG) { 109 continue; 110 } 111 dr = Drawable.createFromXmlInner(r, parser, attrs, theme); 112 } 113 114 if (dr == null) { 115 throw new IllegalArgumentException("No drawable specified for <scale>"); 116 } 117 118 mScaleState.mDrawable = dr; 119 mScaleState.mScaleWidth = sw; 120 mScaleState.mScaleHeight = sh; 121 mScaleState.mGravity = g; 122 mScaleState.mUseIntrinsicSizeAsMin = min; 123 if (dr != null) { 124 dr.setCallback(this); 125 } 126 } 127 128 // overrides from Drawable.Callback 129 130 public void invalidateDrawable(Drawable who) { 131 if (getCallback() != null) { 132 getCallback().invalidateDrawable(this); 133 } 134 } 135 136 public void scheduleDrawable(Drawable who, Runnable what, long when) { 137 if (getCallback() != null) { 138 getCallback().scheduleDrawable(this, what, when); 139 } 140 } 141 142 public void unscheduleDrawable(Drawable who, Runnable what) { 143 if (getCallback() != null) { 144 getCallback().unscheduleDrawable(this, what); 145 } 146 } 147 148 // overrides from Drawable 149 150 @Override 151 public void draw(Canvas canvas) { 152 if (mScaleState.mDrawable.getLevel() != 0) 153 mScaleState.mDrawable.draw(canvas); 154 } 155 156 @Override 157 public int getChangingConfigurations() { 158 return super.getChangingConfigurations() 159 | mScaleState.mChangingConfigurations 160 | mScaleState.mDrawable.getChangingConfigurations(); 161 } 162 163 @Override 164 public boolean getPadding(Rect padding) { 165 // XXX need to adjust padding! 166 return mScaleState.mDrawable.getPadding(padding); 167 } 168 169 @Override 170 public boolean setVisible(boolean visible, boolean restart) { 171 mScaleState.mDrawable.setVisible(visible, restart); 172 return super.setVisible(visible, restart); 173 } 174 175 @Override 176 public void setAlpha(int alpha) { 177 mScaleState.mDrawable.setAlpha(alpha); 178 } 179 180 @Override 181 public int getAlpha() { 182 return mScaleState.mDrawable.getAlpha(); 183 } 184 185 @Override 186 public void setColorFilter(ColorFilter cf) { 187 mScaleState.mDrawable.setColorFilter(cf); 188 } 189 190 @Override 191 public int getOpacity() { 192 return mScaleState.mDrawable.getOpacity(); 193 } 194 195 @Override 196 public boolean isStateful() { 197 return mScaleState.mDrawable.isStateful(); 198 } 199 200 @Override 201 protected boolean onStateChange(int[] state) { 202 boolean changed = mScaleState.mDrawable.setState(state); 203 onBoundsChange(getBounds()); 204 return changed; 205 } 206 207 @Override 208 protected boolean onLevelChange(int level) { 209 mScaleState.mDrawable.setLevel(level); 210 onBoundsChange(getBounds()); 211 invalidateSelf(); 212 return true; 213 } 214 215 @Override 216 protected void onBoundsChange(Rect bounds) { 217 final Rect r = mTmpRect; 218 final boolean min = mScaleState.mUseIntrinsicSizeAsMin; 219 int level = getLevel(); 220 int w = bounds.width(); 221 if (mScaleState.mScaleWidth > 0) { 222 final int iw = min ? mScaleState.mDrawable.getIntrinsicWidth() : 0; 223 w -= (int) ((w - iw) * (10000 - level) * mScaleState.mScaleWidth / 10000); 224 } 225 int h = bounds.height(); 226 if (mScaleState.mScaleHeight > 0) { 227 final int ih = min ? mScaleState.mDrawable.getIntrinsicHeight() : 0; 228 h -= (int) ((h - ih) * (10000 - level) * mScaleState.mScaleHeight / 10000); 229 } 230 final int layoutDirection = getLayoutDirection(); 231 Gravity.apply(mScaleState.mGravity, w, h, bounds, r, layoutDirection); 232 233 if (w > 0 && h > 0) { 234 mScaleState.mDrawable.setBounds(r.left, r.top, r.right, r.bottom); 235 } 236 } 237 238 @Override 239 public int getIntrinsicWidth() { 240 return mScaleState.mDrawable.getIntrinsicWidth(); 241 } 242 243 @Override 244 public int getIntrinsicHeight() { 245 return mScaleState.mDrawable.getIntrinsicHeight(); 246 } 247 248 @Override 249 public ConstantState getConstantState() { 250 if (mScaleState.canConstantState()) { 251 mScaleState.mChangingConfigurations = getChangingConfigurations(); 252 return mScaleState; 253 } 254 return null; 255 } 256 257 @Override 258 public Drawable mutate() { 259 if (!mMutated && super.mutate() == this) { 260 mScaleState.mDrawable.mutate(); 261 mMutated = true; 262 } 263 return this; 264 } 265 266 final static class ScaleState extends ConstantState { 267 Drawable mDrawable; 268 int mChangingConfigurations; 269 float mScaleWidth; 270 float mScaleHeight; 271 int mGravity; 272 boolean mUseIntrinsicSizeAsMin; 273 274 private boolean mCheckedConstantState; 275 private boolean mCanConstantState; 276 277 ScaleState(ScaleState orig, ScaleDrawable owner, Resources res) { 278 if (orig != null) { 279 if (res != null) { 280 mDrawable = orig.mDrawable.getConstantState().newDrawable(res); 281 } else { 282 mDrawable = orig.mDrawable.getConstantState().newDrawable(); 283 } 284 mDrawable.setCallback(owner); 285 mDrawable.setLayoutDirection(orig.mDrawable.getLayoutDirection()); 286 mScaleWidth = orig.mScaleWidth; 287 mScaleHeight = orig.mScaleHeight; 288 mGravity = orig.mGravity; 289 mUseIntrinsicSizeAsMin = orig.mUseIntrinsicSizeAsMin; 290 mCheckedConstantState = mCanConstantState = true; 291 } 292 } 293 294 @Override 295 public Drawable newDrawable() { 296 return new ScaleDrawable(this, null); 297 } 298 299 @Override 300 public Drawable newDrawable(Resources res) { 301 return new ScaleDrawable(this, res); 302 } 303 304 @Override 305 public int getChangingConfigurations() { 306 return mChangingConfigurations; 307 } 308 309 boolean canConstantState() { 310 if (!mCheckedConstantState) { 311 mCanConstantState = mDrawable.getConstantState() != null; 312 mCheckedConstantState = true; 313 } 314 315 return mCanConstantState; 316 } 317 } 318 319 private ScaleDrawable(ScaleState state, Resources res) { 320 mScaleState = new ScaleState(state, this, res); 321 } 322} 323 324