BubbleTextView.java revision bc239a15464f543a41b960b946aa77258454efaf
1/* 2 * Copyright (C) 2008 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 com.android.launcher2; 18 19import android.content.Context; 20import android.content.res.Resources; 21import android.graphics.Bitmap; 22import android.graphics.Canvas; 23import android.graphics.Color; 24import android.graphics.Paint; 25import android.graphics.Rect; 26import android.graphics.Region; 27import android.graphics.Region.Op; 28import android.graphics.drawable.Drawable; 29import android.util.AttributeSet; 30import android.view.MotionEvent; 31import android.widget.TextView; 32 33import com.android.launcher.R; 34 35/** 36 * TextView that draws a bubble behind the text. We cannot use a LineBackgroundSpan 37 * because we want to make the bubble taller than the text and TextView's clip is 38 * too aggressive. 39 */ 40public class BubbleTextView extends TextView { 41 static final float CORNER_RADIUS = 4.0f; 42 static final float SHADOW_LARGE_RADIUS = 4.0f; 43 static final float SHADOW_SMALL_RADIUS = 1.75f; 44 static final float SHADOW_Y_OFFSET = 2.0f; 45 static final int SHADOW_LARGE_COLOUR = 0xDD000000; 46 static final int SHADOW_SMALL_COLOUR = 0xCC000000; 47 static final float PADDING_H = 8.0f; 48 static final float PADDING_V = 3.0f; 49 50 private Paint mPaint; 51 private float mBubbleColorAlpha; 52 private int mPrevAlpha = -1; 53 54 private final HolographicOutlineHelper mOutlineHelper = new HolographicOutlineHelper(); 55 private final Canvas mTempCanvas = new Canvas(); 56 private final Rect mTempRect = new Rect(); 57 private boolean mDidInvalidateForPressedState; 58 private Bitmap mPressedOrFocusedBackground; 59 private int mFocusedOutlineColor; 60 private int mFocusedGlowColor; 61 private int mPressedOutlineColor; 62 private int mPressedGlowColor; 63 64 private boolean mBackgroundSizeChanged; 65 private Drawable mBackground; 66 67 private boolean mStayPressed; 68 69 public BubbleTextView(Context context) { 70 super(context); 71 init(); 72 } 73 74 public BubbleTextView(Context context, AttributeSet attrs) { 75 super(context, attrs); 76 init(); 77 } 78 79 public BubbleTextView(Context context, AttributeSet attrs, int defStyle) { 80 super(context, attrs, defStyle); 81 init(); 82 } 83 84 private void init() { 85 mBackground = getBackground(); 86 87 final Resources res = getContext().getResources(); 88 int bubbleColor = res.getColor(R.color.bubble_dark_background); 89 mPaint = new Paint(Paint.ANTI_ALIAS_FLAG); 90 mPaint.setColor(bubbleColor); 91 mBubbleColorAlpha = Color.alpha(bubbleColor) / 255.0f; 92 mFocusedOutlineColor = mFocusedGlowColor = mPressedOutlineColor = mPressedGlowColor = 93 res.getColor(android.R.color.holo_blue_light); 94 95 setShadowLayer(SHADOW_LARGE_RADIUS, 0.0f, SHADOW_Y_OFFSET, SHADOW_LARGE_COLOUR); 96 } 97 98 public void applyFromShortcutInfo(ShortcutInfo info, IconCache iconCache) { 99 Bitmap b = info.getIcon(iconCache); 100 101 setCompoundDrawablesWithIntrinsicBounds(null, 102 new FastBitmapDrawable(b), 103 null, null); 104 setText(info.title); 105 setTag(info); 106 } 107 108 @Override 109 protected boolean setFrame(int left, int top, int right, int bottom) { 110 if (mLeft != left || mRight != right || mTop != top || mBottom != bottom) { 111 mBackgroundSizeChanged = true; 112 } 113 return super.setFrame(left, top, right, bottom); 114 } 115 116 @Override 117 protected boolean verifyDrawable(Drawable who) { 118 return who == mBackground || super.verifyDrawable(who); 119 } 120 121 @Override 122 protected void drawableStateChanged() { 123 if (isPressed()) { 124 // In this case, we have already created the pressed outline on ACTION_DOWN, 125 // so we just need to do an invalidate to trigger draw 126 if (!mDidInvalidateForPressedState) { 127 setCellLayoutPressedOrFocusedIcon(); 128 } 129 } else { 130 // Otherwise, either clear the pressed/focused background, or create a background 131 // for the focused state 132 final boolean backgroundEmptyBefore = mPressedOrFocusedBackground == null; 133 if (!mStayPressed) { 134 mPressedOrFocusedBackground = null; 135 } 136 if (isFocused()) { 137 if (mLayout == null) { 138 // In some cases, we get focus before we have been layed out. Set the 139 // background to null so that it will get created when the view is drawn. 140 mPressedOrFocusedBackground = null; 141 } else { 142 mPressedOrFocusedBackground = createGlowingOutline( 143 mTempCanvas, mFocusedGlowColor, mFocusedOutlineColor); 144 } 145 mStayPressed = false; 146 setCellLayoutPressedOrFocusedIcon(); 147 } 148 final boolean backgroundEmptyNow = mPressedOrFocusedBackground == null; 149 if (!backgroundEmptyBefore && backgroundEmptyNow) { 150 setCellLayoutPressedOrFocusedIcon(); 151 } 152 } 153 154 Drawable d = mBackground; 155 if (d != null && d.isStateful()) { 156 d.setState(getDrawableState()); 157 } 158 super.drawableStateChanged(); 159 } 160 161 /** 162 * Draw this BubbleTextView into the given Canvas. 163 * 164 * @param destCanvas the canvas to draw on 165 * @param padding the horizontal and vertical padding to use when drawing 166 */ 167 private void drawWithPadding(Canvas destCanvas, int padding) { 168 final Rect clipRect = mTempRect; 169 getDrawingRect(clipRect); 170 171 // adjust the clip rect so that we don't include the text label 172 clipRect.bottom = 173 getExtendedPaddingTop() - (int) BubbleTextView.PADDING_V + getLayout().getLineTop(0); 174 175 // Draw the View into the bitmap. 176 // The translate of scrollX and scrollY is necessary when drawing TextViews, because 177 // they set scrollX and scrollY to large values to achieve centered text 178 destCanvas.save(); 179 destCanvas.scale(getScaleX(), getScaleY(), getWidth() / 2, getHeight() / 2); 180 destCanvas.translate(-getScrollX() + padding / 2, -getScrollY() + padding / 2); 181 destCanvas.clipRect(clipRect, Op.REPLACE); 182 draw(destCanvas); 183 destCanvas.restore(); 184 } 185 186 /** 187 * Returns a new bitmap to be used as the object outline, e.g. to visualize the drop location. 188 * Responsibility for the bitmap is transferred to the caller. 189 */ 190 private Bitmap createGlowingOutline(Canvas canvas, int outlineColor, int glowColor) { 191 final int padding = HolographicOutlineHelper.MAX_OUTER_BLUR_RADIUS; 192 final Bitmap b = Bitmap.createBitmap( 193 getWidth() + padding, getHeight() + padding, Bitmap.Config.ARGB_8888); 194 195 canvas.setBitmap(b); 196 drawWithPadding(canvas, padding); 197 mOutlineHelper.applyExtraThickExpensiveOutlineWithBlur(b, canvas, glowColor, outlineColor); 198 canvas.setBitmap(null); 199 200 return b; 201 } 202 203 @Override 204 public boolean onTouchEvent(MotionEvent event) { 205 // Call the superclass onTouchEvent first, because sometimes it changes the state to 206 // isPressed() on an ACTION_UP 207 boolean result = super.onTouchEvent(event); 208 209 switch (event.getAction()) { 210 case MotionEvent.ACTION_DOWN: 211 // So that the pressed outline is visible immediately when isPressed() is true, 212 // we pre-create it on ACTION_DOWN (it takes a small but perceptible amount of time 213 // to create it) 214 if (mPressedOrFocusedBackground == null) { 215 mPressedOrFocusedBackground = createGlowingOutline( 216 mTempCanvas, mPressedGlowColor, mPressedOutlineColor); 217 } 218 // Invalidate so the pressed state is visible, or set a flag so we know that we 219 // have to call invalidate as soon as the state is "pressed" 220 if (isPressed()) { 221 mDidInvalidateForPressedState = true; 222 setCellLayoutPressedOrFocusedIcon(); 223 } else { 224 mDidInvalidateForPressedState = false; 225 } 226 break; 227 case MotionEvent.ACTION_CANCEL: 228 case MotionEvent.ACTION_UP: 229 // If we've touched down and up on an item, and it's still not "pressed", then 230 // destroy the pressed outline 231 if (!isPressed()) { 232 mPressedOrFocusedBackground = null; 233 } 234 break; 235 } 236 return result; 237 } 238 239 void setStayPressed(boolean stayPressed) { 240 mStayPressed = stayPressed; 241 if (!stayPressed) { 242 mPressedOrFocusedBackground = null; 243 } 244 setCellLayoutPressedOrFocusedIcon(); 245 } 246 247 void setCellLayoutPressedOrFocusedIcon() { 248 if (getParent() instanceof CellLayoutChildren) { 249 CellLayoutChildren parent = (CellLayoutChildren) getParent(); 250 if (parent != null) { 251 CellLayout layout = (CellLayout) parent.getParent(); 252 layout.setPressedOrFocusedIcon((mPressedOrFocusedBackground != null) ? this : null); 253 } 254 } 255 } 256 257 void clearPressedOrFocusedBackground() { 258 mPressedOrFocusedBackground = null; 259 setCellLayoutPressedOrFocusedIcon(); 260 } 261 262 Bitmap getPressedOrFocusedBackground() { 263 return mPressedOrFocusedBackground; 264 } 265 266 int getPressedOrFocusedBackgroundPadding() { 267 return HolographicOutlineHelper.MAX_OUTER_BLUR_RADIUS / 2; 268 } 269 270 @Override 271 public void draw(Canvas canvas) { 272 final Drawable background = mBackground; 273 if (background != null) { 274 final int scrollX = mScrollX; 275 final int scrollY = mScrollY; 276 277 if (mBackgroundSizeChanged) { 278 background.setBounds(0, 0, mRight - mLeft, mBottom - mTop); 279 mBackgroundSizeChanged = false; 280 } 281 282 if ((scrollX | scrollY) == 0) { 283 background.draw(canvas); 284 } else { 285 canvas.translate(scrollX, scrollY); 286 background.draw(canvas); 287 canvas.translate(-scrollX, -scrollY); 288 } 289 } 290 291 // If text is transparent, don't draw any shadow 292 if (getCurrentTextColor() == getResources().getColor(android.R.color.transparent)) { 293 getPaint().clearShadowLayer(); 294 super.draw(canvas); 295 return; 296 } 297 298 // We enhance the shadow by drawing the shadow twice 299 getPaint().setShadowLayer(SHADOW_LARGE_RADIUS, 0.0f, SHADOW_Y_OFFSET, SHADOW_LARGE_COLOUR); 300 super.draw(canvas); 301 canvas.save(Canvas.CLIP_SAVE_FLAG); 302 canvas.clipRect(mScrollX, mScrollY + getExtendedPaddingTop(), mScrollX + getWidth(), 303 mScrollY + getHeight(), Region.Op.INTERSECT); 304 getPaint().setShadowLayer(SHADOW_SMALL_RADIUS, 0.0f, 0.0f, SHADOW_SMALL_COLOUR); 305 super.draw(canvas); 306 canvas.restore(); 307 } 308 309 @Override 310 protected void onAttachedToWindow() { 311 super.onAttachedToWindow(); 312 if (mBackground != null) mBackground.setCallback(this); 313 } 314 315 @Override 316 protected void onDetachedFromWindow() { 317 super.onDetachedFromWindow(); 318 if (mBackground != null) mBackground.setCallback(null); 319 } 320 321 @Override 322 protected boolean onSetAlpha(int alpha) { 323 if (mPrevAlpha != alpha) { 324 mPrevAlpha = alpha; 325 mPaint.setAlpha((int) (alpha * mBubbleColorAlpha)); 326 super.onSetAlpha(alpha); 327 } 328 return true; 329 } 330} 331