BubbleTextView.java revision bdb5c5342adc550559fd723af461e53248f2fba8
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 com.android.launcher.R; 20 21import android.content.Context; 22import android.content.res.Resources; 23import android.graphics.Bitmap; 24import android.graphics.Canvas; 25import android.graphics.Color; 26import android.graphics.Paint; 27import android.graphics.Rect; 28import android.graphics.Region; 29import android.graphics.Region.Op; 30import android.graphics.drawable.Drawable; 31import android.util.AttributeSet; 32import android.view.MotionEvent; 33import android.view.View; 34import android.widget.TextView; 35 36/** 37 * TextView that draws a bubble behind the text. We cannot use a LineBackgroundSpan 38 * because we want to make the bubble taller than the text and TextView's clip is 39 * too aggressive. 40 */ 41public class BubbleTextView extends TextView implements VisibilityChangedBroadcaster { 42 static final float CORNER_RADIUS = 4.0f; 43 static final float SHADOW_LARGE_RADIUS = 4.0f; 44 static final float SHADOW_SMALL_RADIUS = 1.75f; 45 static final float SHADOW_Y_OFFSET = 2.0f; 46 static final int SHADOW_LARGE_COLOUR = 0xCC000000; 47 static final int SHADOW_SMALL_COLOUR = 0xBB000000; 48 static final float PADDING_H = 8.0f; 49 static final float PADDING_V = 3.0f; 50 51 private Paint mPaint; 52 private float mBubbleColorAlpha; 53 private int mPrevAlpha = -1; 54 55 private final HolographicOutlineHelper mOutlineHelper = new HolographicOutlineHelper(); 56 private final Canvas mTempCanvas = new Canvas(); 57 private final Rect mTempRect = new Rect(); 58 private final Paint mTempPaint = new Paint(); 59 private boolean mDidInvalidateForPressedState; 60 private Bitmap mPressedOrFocusedBackground; 61 private int mFocusedOutlineColor; 62 private int mFocusedGlowColor; 63 private int mPressedOutlineColor; 64 private int mPressedGlowColor; 65 66 private boolean mBackgroundSizeChanged; 67 private Drawable mBackground; 68 69 private VisibilityChangedListener mOnVisibilityChangedListener; 70 71 public BubbleTextView(Context context) { 72 super(context); 73 init(); 74 } 75 76 public BubbleTextView(Context context, AttributeSet attrs) { 77 super(context, attrs); 78 init(); 79 } 80 81 public BubbleTextView(Context context, AttributeSet attrs, int defStyle) { 82 super(context, attrs, defStyle); 83 init(); 84 } 85 86 private void init() { 87 mBackground = getBackground(); 88 setFocusable(true); 89 setBackgroundDrawable(null); 90 91 final Resources res = getContext().getResources(); 92 int bubbleColor = res.getColor(R.color.bubble_dark_background); 93 mPaint = new Paint(Paint.ANTI_ALIAS_FLAG); 94 mPaint.setColor(bubbleColor); 95 mBubbleColorAlpha = Color.alpha(bubbleColor) / 255.0f; 96 mFocusedOutlineColor = res.getColor(R.color.workspace_item_focused_outline_color); 97 mFocusedGlowColor = res.getColor(R.color.workspace_item_focused_glow_color); 98 mPressedOutlineColor = res.getColor(R.color.workspace_item_pressed_outline_color); 99 mPressedGlowColor = res.getColor(R.color.workspace_item_pressed_glow_color); 100 } 101 102 public void applyFromShortcutInfo(ShortcutInfo info, IconCache iconCache) { 103 Bitmap b = info.getIcon(iconCache); 104 105 setCompoundDrawablesWithIntrinsicBounds(null, 106 new FastBitmapDrawable(b), 107 null, null); 108 setText(info.title); 109 setTag(info); 110 } 111 112 @Override 113 protected boolean setFrame(int left, int top, int right, int bottom) { 114 if (mLeft != left || mRight != right || mTop != top || mBottom != bottom) { 115 mBackgroundSizeChanged = true; 116 } 117 return super.setFrame(left, top, right, bottom); 118 } 119 120 @Override 121 protected boolean verifyDrawable(Drawable who) { 122 return who == mBackground || super.verifyDrawable(who); 123 } 124 125 @Override 126 protected void drawableStateChanged() { 127 if (isPressed()) { 128 // In this case, we have already created the pressed outline on ACTION_DOWN, 129 // so we just need to do an invalidate to trigger draw 130 if (!mDidInvalidateForPressedState) { 131 invalidate(); 132 } 133 } else { 134 // Otherwise, either clear the pressed/focused background, or create a background 135 // for the focused state 136 final boolean backgroundEmptyBefore = mPressedOrFocusedBackground == null; 137 mPressedOrFocusedBackground = null; 138 if (isFocused()) { 139 mPressedOrFocusedBackground = createGlowingOutline( 140 mTempCanvas, mFocusedGlowColor, mFocusedOutlineColor); 141 invalidate(); 142 } 143 final boolean backgroundEmptyNow = mPressedOrFocusedBackground == null; 144 if (!backgroundEmptyBefore && backgroundEmptyNow) { 145 invalidate(); 146 } 147 } 148 149 Drawable d = mBackground; 150 if (d != null && d.isStateful()) { 151 d.setState(getDrawableState()); 152 } 153 super.drawableStateChanged(); 154 } 155 156 /** 157 * Draw the View v into the given Canvas. 158 * 159 * @param v the view to draw 160 * @param destCanvas the canvas to draw on 161 * @param padding the horizontal and vertical padding to use when drawing 162 */ 163 private void drawWithPadding(Canvas destCanvas, int padding) { 164 final Rect clipRect = mTempRect; 165 getDrawingRect(clipRect); 166 167 // adjust the clip rect so that we don't include the text label 168 clipRect.bottom = 169 getExtendedPaddingTop() - (int) BubbleTextView.PADDING_V + getLayout().getLineTop(0); 170 171 // Draw the View into the bitmap. 172 // The translate of scrollX and scrollY is necessary when drawing TextViews, because 173 // they set scrollX and scrollY to large values to achieve centered text 174 destCanvas.save(); 175 destCanvas.translate(-getScrollX() + padding / 2, -getScrollY() + padding / 2); 176 destCanvas.clipRect(clipRect, Op.REPLACE); 177 draw(destCanvas); 178 destCanvas.restore(); 179 } 180 181 /** 182 * Returns a new bitmap to be used as the object outline, e.g. to visualize the drop location. 183 * Responsibility for the bitmap is transferred to the caller. 184 */ 185 private Bitmap createGlowingOutline(Canvas canvas, int outlineColor, int glowColor) { 186 final int padding = HolographicOutlineHelper.MAX_OUTER_BLUR_RADIUS; 187 final Bitmap b = Bitmap.createBitmap( 188 getWidth() + padding, getHeight() + padding, Bitmap.Config.ARGB_8888); 189 190 canvas.setBitmap(b); 191 drawWithPadding(canvas, padding); 192 mOutlineHelper.applyExtraThickExpensiveOutlineWithBlur(b, canvas, glowColor, outlineColor); 193 194 return b; 195 } 196 197 @Override 198 public boolean onTouchEvent(MotionEvent event) { 199 // Call the superclass onTouchEvent first, because sometimes it changes the state to 200 // isPressed() on an ACTION_UP 201 boolean result = super.onTouchEvent(event); 202 203 switch (event.getAction()) { 204 case MotionEvent.ACTION_DOWN: 205 // So that the pressed outline is visible immediately when isPressed() is true, 206 // we pre-create it on ACTION_DOWN (it takes a small but perceptible amount of time 207 // to create it) 208 if (mPressedOrFocusedBackground == null) { 209 mPressedOrFocusedBackground = createGlowingOutline( 210 mTempCanvas, mPressedGlowColor, mPressedOutlineColor); 211 } 212 // Invalidate so the pressed state is visible, or set a flag so we know that we 213 // have to call invalidate as soon as the state is "pressed" 214 if (isPressed()) { 215 mDidInvalidateForPressedState = true; 216 invalidate(); 217 } else { 218 mDidInvalidateForPressedState = false; 219 } 220 break; 221 case MotionEvent.ACTION_CANCEL: 222 case MotionEvent.ACTION_UP: 223 // If we've touched down and up on an item, and it's still not "pressed", then 224 // destroy the pressed outline 225 if (!isPressed()) { 226 mPressedOrFocusedBackground = null; 227 } 228 break; 229 } 230 return result; 231 } 232 233 public void setVisibilityChangedListener(VisibilityChangedListener listener) { 234 mOnVisibilityChangedListener = listener; 235 } 236 237 @Override 238 protected void onVisibilityChanged(View changedView, int visibility) { 239 if (mOnVisibilityChangedListener != null) { 240 mOnVisibilityChangedListener.receiveVisibilityChangedMessage(this); 241 } 242 super.onVisibilityChanged(changedView, visibility); 243 } 244 245 @Override 246 public void draw(Canvas canvas) { 247 if (mPressedOrFocusedBackground != null && (isPressed() || isFocused())) { 248 // The blue glow can extend outside of our clip region, so we first temporarily expand 249 // the canvas's clip region 250 canvas.save(Canvas.CLIP_SAVE_FLAG); 251 int padding = HolographicOutlineHelper.MAX_OUTER_BLUR_RADIUS / 2; 252 canvas.clipRect(-padding + mScrollX, -padding + mScrollY, 253 getWidth() + padding + mScrollX, getHeight() + padding + mScrollY, 254 Region.Op.REPLACE); 255 // draw blue glow 256 canvas.drawBitmap(mPressedOrFocusedBackground, 257 mScrollX - padding, mScrollY - padding, mTempPaint); 258 canvas.restore(); 259 } 260 261 final Drawable background = mBackground; 262 if (background != null) { 263 final int scrollX = mScrollX; 264 final int scrollY = mScrollY; 265 266 if (mBackgroundSizeChanged) { 267 background.setBounds(0, 0, mRight - mLeft, mBottom - mTop); 268 mBackgroundSizeChanged = false; 269 } 270 271 if ((scrollX | scrollY) == 0) { 272 background.draw(canvas); 273 } else { 274 canvas.translate(scrollX, scrollY); 275 background.draw(canvas); 276 canvas.translate(-scrollX, -scrollY); 277 } 278 } 279 // We enhance the shadow by drawing the shadow twice 280 setShadowLayer(SHADOW_LARGE_RADIUS, 0.0f, SHADOW_Y_OFFSET, SHADOW_LARGE_COLOUR); 281 super.draw(canvas); 282 canvas.save(Canvas.CLIP_SAVE_FLAG); 283 canvas.clipRect(mScrollX, mScrollY + getExtendedPaddingTop(), mScrollX + getWidth(), 284 mScrollY + getHeight(), Region.Op.REPLACE); 285 setShadowLayer(SHADOW_SMALL_RADIUS, 0.0f, 0.0f, SHADOW_SMALL_COLOUR); 286 super.draw(canvas); 287 canvas.restore(); 288 } 289 290 @Override 291 protected void onAttachedToWindow() { 292 super.onAttachedToWindow(); 293 if (mBackground != null) mBackground.setCallback(this); 294 } 295 296 @Override 297 protected void onDetachedFromWindow() { 298 super.onDetachedFromWindow(); 299 if (mBackground != null) mBackground.setCallback(null); 300 } 301 302 @Override 303 protected boolean onSetAlpha(int alpha) { 304 if (mPrevAlpha != alpha) { 305 mPrevAlpha = alpha; 306 mPaint.setAlpha((int) (alpha * mBubbleColorAlpha)); 307 super.onSetAlpha(alpha); 308 } 309 return true; 310 } 311} 312