ShapeDrawable.java revision 6efd2bad954e0e5bd74916a32f036a0f149dcd4d
1/* 2 * Copyright (C) 2007 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 android.graphics.*; 20import android.graphics.drawable.shapes.Shape; 21import android.content.res.Resources; 22import android.content.res.TypedArray; 23import android.util.AttributeSet; 24 25import org.xmlpull.v1.XmlPullParser; 26import org.xmlpull.v1.XmlPullParserException; 27 28import java.io.IOException; 29 30/** 31 * A Drawable object that draws primitive shapes. 32 * A ShapeDrawable takes a {@link android.graphics.drawable.shapes.Shape} 33 * object and manages its presence on the screen. If no Shape is given, then 34 * the ShapeDrawable will default to a 35 * {@link android.graphics.drawable.shapes.RectShape}. 36 * 37 * <p>It can be defined in an XML file with the <code><shape></code> element. For more 38 * information, see the guide to <a 39 * href="{@docRoot}guide/topics/resources/drawable-resource.html">Drawable Resources</a>.</p> 40 * 41 * @attr ref android.R.styleable#ShapeDrawablePadding_left 42 * @attr ref android.R.styleable#ShapeDrawablePadding_top 43 * @attr ref android.R.styleable#ShapeDrawablePadding_right 44 * @attr ref android.R.styleable#ShapeDrawablePadding_bottom 45 * @attr ref android.R.styleable#ShapeDrawable_color 46 * @attr ref android.R.styleable#ShapeDrawable_width 47 * @attr ref android.R.styleable#ShapeDrawable_height 48 */ 49public class ShapeDrawable extends Drawable { 50 private ShapeState mShapeState; 51 private boolean mMutated; 52 53 /** 54 * ShapeDrawable constructor. 55 */ 56 public ShapeDrawable() { 57 this((ShapeState) null); 58 } 59 60 /** 61 * Creates a ShapeDrawable with a specified Shape. 62 * 63 * @param s the Shape that this ShapeDrawable should be 64 */ 65 public ShapeDrawable(Shape s) { 66 this((ShapeState) null); 67 68 mShapeState.mShape = s; 69 } 70 71 private ShapeDrawable(ShapeState state) { 72 mShapeState = new ShapeState(state); 73 } 74 75 /** 76 * Returns the Shape of this ShapeDrawable. 77 */ 78 public Shape getShape() { 79 return mShapeState.mShape; 80 } 81 82 /** 83 * Sets the Shape of this ShapeDrawable. 84 */ 85 public void setShape(Shape s) { 86 mShapeState.mShape = s; 87 updateShape(); 88 } 89 90 /** 91 * Sets a ShaderFactory to which requests for a 92 * {@link android.graphics.Shader} object will be made. 93 * 94 * @param fact an instance of your ShaderFactory implementation 95 */ 96 public void setShaderFactory(ShaderFactory fact) { 97 mShapeState.mShaderFactory = fact; 98 } 99 100 /** 101 * Returns the ShaderFactory used by this ShapeDrawable for requesting a 102 * {@link android.graphics.Shader}. 103 */ 104 public ShaderFactory getShaderFactory() { 105 return mShapeState.mShaderFactory; 106 } 107 108 /** 109 * Returns the Paint used to draw the shape. 110 */ 111 public Paint getPaint() { 112 return mShapeState.mPaint; 113 } 114 115 /** 116 * Sets padding for the shape. 117 * 118 * @param left padding for the left side (in pixels) 119 * @param top padding for the top (in pixels) 120 * @param right padding for the right side (in pixels) 121 * @param bottom padding for the bottom (in pixels) 122 */ 123 public void setPadding(int left, int top, int right, int bottom) { 124 if ((left | top | right | bottom) == 0) { 125 mShapeState.mPadding = null; 126 } else { 127 if (mShapeState.mPadding == null) { 128 mShapeState.mPadding = new Rect(); 129 } 130 mShapeState.mPadding.set(left, top, right, bottom); 131 } 132 invalidateSelf(); 133 } 134 135 /** 136 * Sets padding for this shape, defined by a Rect object. 137 * Define the padding in the Rect object as: left, top, right, bottom. 138 */ 139 public void setPadding(Rect padding) { 140 if (padding == null) { 141 mShapeState.mPadding = null; 142 } else { 143 if (mShapeState.mPadding == null) { 144 mShapeState.mPadding = new Rect(); 145 } 146 mShapeState.mPadding.set(padding); 147 } 148 invalidateSelf(); 149 } 150 151 /** 152 * Sets the intrinsic (default) width for this shape. 153 * 154 * @param width the intrinsic width (in pixels) 155 */ 156 public void setIntrinsicWidth(int width) { 157 mShapeState.mIntrinsicWidth = width; 158 invalidateSelf(); 159 } 160 161 /** 162 * Sets the intrinsic (default) height for this shape. 163 * 164 * @param height the intrinsic height (in pixels) 165 */ 166 public void setIntrinsicHeight(int height) { 167 mShapeState.mIntrinsicHeight = height; 168 invalidateSelf(); 169 } 170 171 @Override 172 public int getIntrinsicWidth() { 173 return mShapeState.mIntrinsicWidth; 174 } 175 176 @Override 177 public int getIntrinsicHeight() { 178 return mShapeState.mIntrinsicHeight; 179 } 180 181 @Override 182 public boolean getPadding(Rect padding) { 183 if (mShapeState.mPadding != null) { 184 padding.set(mShapeState.mPadding); 185 return true; 186 } else { 187 return super.getPadding(padding); 188 } 189 } 190 191 private static int modulateAlpha(int paintAlpha, int alpha) { 192 int scale = alpha + (alpha >>> 7); // convert to 0..256 193 return paintAlpha * scale >>> 8; 194 } 195 196 /** 197 * Called from the drawable's draw() method after the canvas has been set 198 * to draw the shape at (0,0). Subclasses can override for special effects 199 * such as multiple layers, stroking, etc. 200 */ 201 protected void onDraw(Shape shape, Canvas canvas, Paint paint) { 202 shape.draw(canvas, paint); 203 } 204 205 @Override 206 public void draw(Canvas canvas) { 207 Rect r = getBounds(); 208 Paint paint = mShapeState.mPaint; 209 210 int prevAlpha = paint.getAlpha(); 211 paint.setAlpha(modulateAlpha(prevAlpha, mShapeState.mAlpha)); 212 213 if (mShapeState.mShape != null) { 214 // need the save both for the translate, and for the (unknown) Shape 215 int count = canvas.save(); 216 canvas.translate(r.left, r.top); 217 onDraw(mShapeState.mShape, canvas, paint); 218 canvas.restoreToCount(count); 219 } else { 220 canvas.drawRect(r, paint); 221 } 222 223 // restore 224 paint.setAlpha(prevAlpha); 225 } 226 227 @Override 228 public int getChangingConfigurations() { 229 return super.getChangingConfigurations() 230 | mShapeState.mChangingConfigurations; 231 } 232 233 /** 234 * Set the alpha level for this drawable [0..255]. Note that this drawable 235 * also has a color in its paint, which has an alpha as well. These two 236 * values are automatically combined during drawing. Thus if the color's 237 * alpha is 75% (i.e. 192) and the drawable's alpha is 50% (i.e. 128), then 238 * the combined alpha that will be used during drawing will be 37.5% 239 * (i.e. 96). 240 */ 241 @Override public void setAlpha(int alpha) { 242 mShapeState.mAlpha = alpha; 243 invalidateSelf(); 244 } 245 246 @Override 247 public void setColorFilter(ColorFilter cf) { 248 mShapeState.mPaint.setColorFilter(cf); 249 invalidateSelf(); 250 } 251 252 @Override 253 public int getOpacity() { 254 if (mShapeState.mShape == null) { 255 final Paint p = mShapeState.mPaint; 256 if (p.getXfermode() == null) { 257 final int alpha = p.getAlpha(); 258 if (alpha == 0) { 259 return PixelFormat.TRANSPARENT; 260 } 261 if (alpha == 255) { 262 return PixelFormat.OPAQUE; 263 } 264 } 265 } 266 // not sure, so be safe 267 return PixelFormat.TRANSLUCENT; 268 } 269 270 @Override 271 public void setDither(boolean dither) { 272 mShapeState.mPaint.setDither(dither); 273 invalidateSelf(); 274 } 275 276 @Override 277 protected void onBoundsChange(Rect bounds) { 278 super.onBoundsChange(bounds); 279 updateShape(); 280 } 281 282 /** 283 * Subclasses override this to parse custom subelements. 284 * If you handle it, return true, else return <em>super.inflateTag(...)</em>. 285 */ 286 protected boolean inflateTag(String name, Resources r, XmlPullParser parser, 287 AttributeSet attrs) { 288 289 if (name.equals("padding")) { 290 TypedArray a = r.obtainAttributes(attrs, 291 com.android.internal.R.styleable.ShapeDrawablePadding); 292 setPadding( 293 a.getDimensionPixelOffset( 294 com.android.internal.R.styleable.ShapeDrawablePadding_left, 0), 295 a.getDimensionPixelOffset( 296 com.android.internal.R.styleable.ShapeDrawablePadding_top, 0), 297 a.getDimensionPixelOffset( 298 com.android.internal.R.styleable.ShapeDrawablePadding_right, 0), 299 a.getDimensionPixelOffset( 300 com.android.internal.R.styleable.ShapeDrawablePadding_bottom, 0)); 301 a.recycle(); 302 return true; 303 } 304 305 return false; 306 } 307 308 @Override 309 public void inflate(Resources r, XmlPullParser parser, AttributeSet attrs) 310 throws XmlPullParserException, IOException { 311 super.inflate(r, parser, attrs); 312 313 TypedArray a = r.obtainAttributes(attrs, com.android.internal.R.styleable.ShapeDrawable); 314 315 int color = mShapeState.mPaint.getColor(); 316 color = a.getColor(com.android.internal.R.styleable.ShapeDrawable_color, color); 317 mShapeState.mPaint.setColor(color); 318 319 setIntrinsicWidth((int) 320 a.getDimension(com.android.internal.R.styleable.ShapeDrawable_width, 0f)); 321 setIntrinsicHeight((int) 322 a.getDimension(com.android.internal.R.styleable.ShapeDrawable_height, 0f)); 323 324 a.recycle(); 325 326 int type; 327 final int outerDepth = parser.getDepth(); 328 while ((type=parser.next()) != XmlPullParser.END_DOCUMENT 329 && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) { 330 if (type != XmlPullParser.START_TAG) { 331 continue; 332 } 333 334 final String name = parser.getName(); 335 // call our subclass 336 if (!inflateTag(name, r, parser, attrs)) { 337 android.util.Log.w("drawable", "Unknown element: " + name + 338 " for ShapeDrawable " + this); 339 } 340 } 341 } 342 343 private void updateShape() { 344 if (mShapeState.mShape != null) { 345 final Rect r = getBounds(); 346 final int w = r.width(); 347 final int h = r.height(); 348 349 mShapeState.mShape.resize(w, h); 350 if (mShapeState.mShaderFactory != null) { 351 mShapeState.mPaint.setShader(mShapeState.mShaderFactory.resize(w, h)); 352 } 353 } 354 invalidateSelf(); 355 } 356 357 @Override 358 public ConstantState getConstantState() { 359 mShapeState.mChangingConfigurations = getChangingConfigurations(); 360 return mShapeState; 361 } 362 363 @Override 364 public Drawable mutate() { 365 if (!mMutated && super.mutate() == this) { 366 mShapeState.mPaint = new Paint(mShapeState.mPaint); 367 mShapeState.mPadding = new Rect(mShapeState.mPadding); 368 try { 369 mShapeState.mShape = mShapeState.mShape.clone(); 370 } catch (CloneNotSupportedException e) { 371 return null; 372 } 373 mMutated = true; 374 } 375 return this; 376 } 377 378 /** 379 * Defines the intrinsic properties of this ShapeDrawable's Shape. 380 */ 381 final static class ShapeState extends ConstantState { 382 int mChangingConfigurations; 383 Paint mPaint; 384 Shape mShape; 385 Rect mPadding; 386 int mIntrinsicWidth; 387 int mIntrinsicHeight; 388 int mAlpha = 255; 389 ShaderFactory mShaderFactory; 390 391 ShapeState(ShapeState orig) { 392 if (orig != null) { 393 mPaint = orig.mPaint; 394 mShape = orig.mShape; 395 mPadding = orig.mPadding; 396 mIntrinsicWidth = orig.mIntrinsicWidth; 397 mIntrinsicHeight = orig.mIntrinsicHeight; 398 mAlpha = orig.mAlpha; 399 mShaderFactory = orig.mShaderFactory; 400 } else { 401 mPaint = new Paint(Paint.ANTI_ALIAS_FLAG); 402 } 403 } 404 405 @Override 406 public Drawable newDrawable() { 407 return new ShapeDrawable(this); 408 } 409 410 @Override 411 public Drawable newDrawable(Resources res) { 412 return new ShapeDrawable(this); 413 } 414 415 @Override 416 public int getChangingConfigurations() { 417 return mChangingConfigurations; 418 } 419 } 420 421 /** 422 * Base class defines a factory object that is called each time the drawable 423 * is resized (has a new width or height). Its resize() method returns a 424 * corresponding shader, or null. 425 * Implement this class if you'd like your ShapeDrawable to use a special 426 * {@link android.graphics.Shader}, such as a 427 * {@link android.graphics.LinearGradient}. 428 * 429 */ 430 public static abstract class ShaderFactory { 431 /** 432 * Returns the Shader to be drawn when a Drawable is drawn. 433 * The dimensions of the Drawable are passed because they may be needed 434 * to adjust how the Shader is configured for drawing. 435 * This is called by ShapeDrawable.setShape(). 436 * 437 * @param width the width of the Drawable being drawn 438 * @param height the heigh of the Drawable being drawn 439 * @return the Shader to be drawn 440 */ 441 public abstract Shader resize(int width, int height); 442 } 443 444 // other subclass could wack the Shader's localmatrix based on the 445 // resize params (e.g. scaletofit, etc.). This could be used to scale 446 // a bitmap to fill the bounds without needing any other special casing. 447} 448 449