Java Code Examples for android.graphics.Canvas#saveLayerAlpha()

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    if (mBytes == null) {
        return;
    }

    // Calc width
    int n = Math.min(numBars, (mBytes == null) ? 0 : mBytes.length);
    int w = n * barWidth + Math.max(0, n - 1) * gapWidth;
    float x = getPlayFraction() * w;

    canvas.saveLayerAlpha(0, 0, x, getHeight(), alphaPlayed,
            Canvas.ALL_SAVE_FLAG);
    drawBars(canvas, paint);
    canvas.restore();
    canvas.saveLayerAlpha(x, 0, getWidth(), getHeight(), alphaUnplayed,
            Canvas.ALL_SAVE_FLAG);
    drawBars(canvas, paint);
    canvas.restore();
}
 

@Override
protected void onDraw(Canvas canvas) {
    canvas.saveLayerAlpha(mSaveLayerRectF, mAlpha, Canvas.MATRIX_SAVE_FLAG
            | Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
            | Canvas.FULL_COLOR_LAYER_SAVE_FLAG | Canvas.CLIP_TO_LAYER_SAVE_FLAG);
    // 绘制蒙板
    canvas.drawBitmap(mMask, 0, mExtendOffsetY, mPaint);
    mPaint.setXfermode(mXfermode);

    // 绘制底部图片
    canvas.drawBitmap(mBottom, mRealPos, mExtendOffsetY, mPaint);
    mPaint.setXfermode(null);
    // 绘制边框
    canvas.drawBitmap(mFrame, 0, mExtendOffsetY, mPaint);

    // 绘制按钮
    canvas.drawBitmap(mCurBtnPic, mRealPos, mExtendOffsetY, mPaint);
    canvas.restore();
}
 

@Override
protected void onDraw(Canvas canvas) {
    int alpha = isEnabled() ? FULL_ALPHA : FULL_ALPHA / 2;
    canvas.saveLayerAlpha(0, 0, mMask.getWidth(), mMask.getHeight(), alpha, Canvas.ALL_SAVE_FLAG);
    // draw mask
    canvas.drawBitmap(mMask, 0, 0, null);
    // draw the background (on or off)
    drawBar(canvas);
    // draw the frame
    mFrame.draw(canvas);
    // draw the slider
    if (mSliderOnAlpha <= FULL_ALPHA) {
        mSliderOff.setBounds(mSliderOffset, 0, mSliderWidth + mSliderOffset, mHeight);
        mSliderOff.draw(canvas);
    }

    mSliderOn.setAlpha(mSliderOnAlpha);
    mSliderOn.setBounds(mSliderOffset, 0, mSliderWidth + mSliderOffset, mHeight);
    mSliderOn.draw(canvas);
    canvas.restore();
}
 

@Override
protected void onDraw(Canvas canvas) {
	super.onDraw(canvas);
	System.out.println("¿ªÊ¼£º"+canvas.getSaveCount());
	paint.setColor(Color.RED);
	paint.setDither(true);
	paint.setAntiAlias(true);
	canvas.drawCircle(100, 100, 100, paint);
	canvas.save();
	System.out.println("save£º"+canvas.getSaveCount());
	canvas.saveLayerAlpha(0, 0, getWidth(), getHeight(), 100, Canvas.ALL_SAVE_FLAG);
	System.out.println("saveLayerAlpha£º"+canvas.getSaveCount());
	canvas.translate(100, 100);
	paint.setColor(Color.BLUE);
	canvas.drawCircle(100, 100, 100, paint);
	canvas.restoreToCount(1);
	System.out.println("restore£º"+canvas.getSaveCount());
}
 

@Override
protected void onDraw(Canvas canvas) {
    canvas.saveLayerAlpha(mSaveLayerRectF, mAlpha, Canvas.MATRIX_SAVE_FLAG
            | Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
            | Canvas.FULL_COLOR_LAYER_SAVE_FLAG | Canvas.CLIP_TO_LAYER_SAVE_FLAG);
    // 绘制蒙板
    canvas.drawBitmap(mMask, 0, mExtendOffsetY, mPaint);
    mPaint.setXfermode(mXfermode);

    // 绘制底部图片
    canvas.drawBitmap(mBottom, mRealPos, mExtendOffsetY, mPaint);
    mPaint.setXfermode(null);
    // 绘制边框
    canvas.drawBitmap(mFrame, 0, mExtendOffsetY, mPaint);

    // 绘制按钮
    canvas.drawBitmap(mCurBtnPic, mRealPos, mExtendOffsetY, mPaint);
    canvas.restore();
}
 

@Override
protected void onDraw(Canvas canvas) {
	canvas.saveLayerAlpha(mSaveLayerRectF, mAlpha, Canvas.MATRIX_SAVE_FLAG
			| Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
			| Canvas.FULL_COLOR_LAYER_SAVE_FLAG
			| Canvas.CLIP_TO_LAYER_SAVE_FLAG);
	// 绘制蒙板
	canvas.drawBitmap(mMask, 0, mExtendOffsetY, mPaint);
	mPaint.setXfermode(mXfermode);

	// 绘制底部图片
	canvas.drawBitmap(mBottom, mRealPos, mExtendOffsetY, mPaint);
	mPaint.setXfermode(null);
	// 绘制边框
	canvas.drawBitmap(mFrame, 0, mExtendOffsetY, mPaint);

	// 绘制按钮
	canvas.drawBitmap(mCurBtnPic, mRealPos, mExtendOffsetY, mPaint);
	canvas.restore();
}
 

/**
 * Convenience for {@link Canvas#saveLayer(RectF, Paint)} but instead of taking a entire Paint
 * object it takes only the {@code alpha} parameter.
 */
public static int saveLayerAlpha(@NonNull Canvas canvas, @Nullable RectF bounds, int alpha) {
  if (VERSION.SDK_INT > VERSION_CODES.LOLLIPOP) {
    return canvas.saveLayerAlpha(bounds, alpha);
  } else {
    return canvas.saveLayerAlpha(bounds, alpha, Canvas.ALL_SAVE_FLAG);
  }
}
 

@Override
public void draw(Canvas canvas) {
  Rect bounds = getBounds();
  canvas.saveLayerAlpha(bounds.left, bounds.top, bounds.right, bounds.bottom, mAlpha, Canvas.ALL_SAVE_FLAG);
  super.draw(canvas);
  canvas.restore();
}
 

@Override
public void draw(Canvas canvas) {
  Rect bounds = getBounds();
  canvas.saveLayerAlpha(bounds.left, bounds.top, bounds.right, bounds.bottom, mAlpha, Canvas.ALL_SAVE_FLAG);
  super.draw(canvas);
  canvas.restore();
}
 

@Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
  super.onDraw(c, parent, state);

  boolean foundFirstChild = false;
  float viewVerticalCenter = 0f;
  float left = 0f;
  float limit = -(layout.getMeasuredWidth() / 2f);
  float initialPosition =
      ((headerSize / 2f) - (layout.getMeasuredWidth() / 2f) - (margin / 2f)) * PARALLAX_RATIO;

  for (int i = 0; i < parent.getChildCount(); i++) {
    View view = parent.getChildAt(i);
    if (viewVerticalCenter == 0f) {
      viewVerticalCenter =
          view.getTop() + (view.getMeasuredHeight() / 2f) - (layout.getMeasuredWidth() / 2f);
    }
    if (parent.getChildAdapterPosition(view) == 0) {
      left =
          view.getLeft() - (headerSize / 2f) - (layout.getMeasuredWidth() / 2f) - (margin / 2f);
      left *= PARALLAX_RATIO;
      if (left < limit) {
        left = limit;
      }
      foundFirstChild = true;
      break;
    }
  }
  if (!foundFirstChild) {
    left = limit;
  }
  // With API <= 23, there's a bug where if alpha is set to 0, TextViews' alpha is not set correctly
  int movementPercentage = Math.max((int) (getPercentage(limit, initialPosition, left) * 255), 1);
  c.save();
  c.saveLayerAlpha(new RectF(0, 0, headerSize - 2, c.getHeight()), movementPercentage,
      Canvas.ALL_SAVE_FLAG);
  c.translate(left, viewVerticalCenter - VERTICAL_OFFSET);
  layout.draw(c);
  c.restore();
}
 

@Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        int width = getWidth();

        if (width != oldWidth) {
            reloadWidth(width);
        }

        if (targetImg == null && sourceImg != null) {
            loadTargetImg(width);
        }

        backgroundRes.draw(canvas);
//        canvas.save();

        if (targetImg != null) {
            targetImg.draw(canvas);
        }

        canvas.saveLayerAlpha(0, 0, width, width, 125, Canvas.ALL_SAVE_FLAG);
//        canvas.save();
        canvas.drawRect(clearBtnRect, backgroundPaint);
        clearBtnRes.draw(canvas);
        canvas.restore();

        drawPoints(canvas);
    }
 

@Override
protected void onDraw(Canvas canvas) {
    canvas.saveLayerAlpha(0, 0, canvas.getWidth(), canvas.getHeight(), 255, Canvas.HAS_ALPHA_LAYER_SAVE_FLAG);
    super.onDraw(canvas);
    canvas.drawPath(mRectanglePath, mEraser);
    //5 is the margin of the close circle
    canvas.drawCircle((int) ((mCloseSize * 0.5) - ((LayoutParams) getLayoutParams()).leftMargin),
            (int) ((mCloseSize * 0.5) - ((LayoutParams) getLayoutParams()).topMargin),
            (int) (((mCloseSize * 0.5) + mCloseButtonMargin)), mEraser);
}
 

@Override
public void draw(Canvas canvas) {
        Rect bounds = getBounds();
        canvas.saveLayerAlpha(bounds.left, bounds.top, bounds.right, bounds.bottom, mAlpha, Canvas.ALL_SAVE_FLAG);
        super.draw(canvas);
        canvas.restore();
}
 

@Override
protected void onDraw(Canvas canvas) {
	canvas.saveLayerAlpha(mSaveLayerRectF, mAlpha, Canvas.MATRIX_SAVE_FLAG | Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG | Canvas.FULL_COLOR_LAYER_SAVE_FLAG
			| Canvas.CLIP_TO_LAYER_SAVE_FLAG);

	// 绘制底部图片
	canvas.drawBitmap(bmCurBgPic, 0, 0, mPaint);

	// 绘制按钮
	canvas.drawBitmap(bmCurBtnPic, curBtnPos, 0, mPaint);

	canvas.restore();
}
 

/**
 * Convenience for {@link #saveLayerAlpha(Canvas, RectF, int)} that takes the four float
 * coordinates of the bounds rectangle.
 */
public static int saveLayerAlpha(
    @NonNull Canvas canvas, float left, float top, float right, float bottom, int alpha) {
  if (VERSION.SDK_INT > VERSION_CODES.LOLLIPOP) {
    return canvas.saveLayerAlpha(left, top, right, bottom, alpha);
  } else {
    return canvas.saveLayerAlpha(left, top, right, bottom, alpha, Canvas.ALL_SAVE_FLAG);
  }
}
 

@Override
protected void dispatchDraw(Canvas canvas) {
  super.dispatchDraw(canvas);

  if (mDragState != IDLE) {
    // draw the divider over the expanded item
    if (mFirstExpPos != mSrcPos) {
      drawDivider(mFirstExpPos, canvas);
    }
    if (mSecondExpPos != mFirstExpPos && mSecondExpPos != mSrcPos) {
      drawDivider(mSecondExpPos, canvas);
    }
  }

  if (mFloatView != null) {
    // draw the float view over everything
    final int w = mFloatView.getWidth();
    final int h = mFloatView.getHeight();

    int x = mFloatLoc.x;

    int width = getWidth();
    if (x < 0) {
      x = - x;
    }
    float alphaMod;
    if (x < width) {
      alphaMod = ((float) (width - x)) / ((float) width);
      alphaMod *= alphaMod;
    }
    else {
      alphaMod = 0;
    }

    final int alpha = (int) (255f * mCurrFloatAlpha * alphaMod);

    canvas.save();
    // Log.d("mobeta", "clip rect bounds: " + canvas.getClipBounds());
    canvas.translate(mFloatLoc.x, mFloatLoc.y);
    canvas.clipRect(0, 0, w, h);

    // Log.d("mobeta", "clip rect bounds: " + canvas.getClipBounds());
    canvas.saveLayerAlpha(0, 0, w, h, alpha, Canvas.ALL_SAVE_FLAG);
    mFloatView.draw(canvas);
    canvas.restore();
    canvas.restore();
  }
}
 

@Override
protected void dispatchDraw(@NonNull Canvas canvas) {
    super.dispatchDraw(canvas);

    if (mDragState != IDLE) {
        // draw the divider over the expanded item
        if (mFirstExpPos != mSrcPos) {
            drawDivider(mFirstExpPos, canvas);
        }
        if (mSecondExpPos != mFirstExpPos && mSecondExpPos != mSrcPos) {
            drawDivider(mSecondExpPos, canvas);
        }
    }

    if (mFloatView != null) {
        // draw the float view over everything
        final int w = mFloatView.getWidth();
        final int h = mFloatView.getHeight();

        int x = mFloatLoc.x;

        int width = getWidth();
        if (x < 0)
            x = -x;
        float alphaMod;
        if (x < width) {
            alphaMod = ((float) (width - x)) / ((float) width);
            alphaMod *= alphaMod;
        } else {
            alphaMod = 0;
        }

        final int alpha = (int) (255f * mCurrFloatAlpha * alphaMod);

        canvas.save();
        // Log.d(tag, "clip rect bounds: " + canvas.getClipBounds());
        canvas.translate(mFloatLoc.x, mFloatLoc.y);
        canvas.clipRect(0, 0, w, h);

        // Log.d(tag, "clip rect bounds: " + canvas.getClipBounds());
        canvas.saveLayerAlpha(0, 0, w, h, alpha, Canvas.ALL_SAVE_FLAG);
        mFloatView.draw(canvas);
        canvas.restore();
        canvas.restore();
    }
}
 

@Override
protected void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(canvas);

    if (mDragState != IDLE) {
        // draw the divider over the expanded item
        if (mFirstExpPos != mSrcPos) {
            drawDivider(mFirstExpPos, canvas);
        }
        if (mSecondExpPos != mFirstExpPos && mSecondExpPos != mSrcPos) {
            drawDivider(mSecondExpPos, canvas);
        }
    }

    if (mFloatView != null) {
        // draw the float view over everything
        final int w = mFloatView.getWidth();
        final int h = mFloatView.getHeight();

        int x = mFloatLoc.x;

        int width = getWidth();
        if (x < 0)
            x = -x;
        float alphaMod;
        if (x < width) {
            alphaMod = ((float) (width - x)) / ((float) width);
            alphaMod *= alphaMod;
        } else {
            alphaMod = 0;
        }

        final int alpha = (int) (255f * mCurrFloatAlpha * alphaMod);

        canvas.save();
        // Log.d("mobeta", "clip rect bounds: " + canvas.getClipBounds());
        canvas.translate(mFloatLoc.x, mFloatLoc.y);
        canvas.clipRect(0, 0, w, h);

        // Log.d("mobeta", "clip rect bounds: " + canvas.getClipBounds());
        canvas.saveLayerAlpha(0, 0, w, h, alpha, Canvas.ALL_SAVE_FLAG);
        mFloatView.draw(canvas);
        canvas.restore();
        canvas.restore();
    }
}
 

@Override
	protected void onDraw(Canvas canvas) {
		
		// 控件宽高
	    int height = getHeight();
	    int width = getWidth();

	    // 单个字母高度
	    float singleHeight = height / (float)ConstChar.length;
	    
	    int workHeight = 0;
	    
	    if( mAlpha == 0 )
	    	return;
	    
	    mPaint.reset();
	    
	    int saveCount = 0;
	    
	    if( mHideAnimation )
	    {
	    	saveCount = canvas.save();
	    	canvas.saveLayerAlpha( 0, 0, width, height, mAlpha, Canvas.ALL_SAVE_FLAG );
	    }
	    
	    for(int i=0;i<ConstChar.length;i++) {
	    	
	       mPaint.setColor(mFontColor);
	       mPaint.setAntiAlias(true);
	       
	       float xPos = width - mWidthOffset;
	       float yPos = workHeight + singleHeight/2;
	       
	       //float adjustX = adjustXPos( yPos, i == mChooseIndex );
	       // 根据当前字母y的位置计算得到字体大小
	       int fontSize = adjustFontSize(i, yPos ); 
	       mPaint.setTextSize(fontSize);
    	   
	       // 添加一个字母的高度
	       workHeight += singleHeight;
	       
	       // 绘制字母
	       drawTextInCenter(canvas, ConstChar[i], xPos + ajustXPosAnimation(i,  yPos )  , yPos );
	       
	       // 绘制的字母和当前触摸到的一致, 绘制红色被选中字母
	       if(i == mChooseIndex) {
	    	   mPaint.setColor( mTipFontColor );
	    	   mPaint.setFakeBoldText(true);
	    	   mPaint.setTextSize( mTipFontSize );
	    	   yPos = mTouch.y;
	    	   
	    	   float pos = 0;
	    	   
	    	   if( mAnimating || mHideAnimation ) {
	    		   pos = mLastFucusPostion.x;
	    		   yPos = mLastFucusPostion.y;
	    	   } else {
	    		   pos = xPos + ajustXPosAnimation(i, yPos ) - mAdditionalTipOffset;
	    		   mLastFucusPostion.x = pos;
	    		   mLastFucusPostion.y = yPos;
	    	   }
	    		   
	    	   drawTextInCenter(canvas, ConstChar[i], pos, yPos );
//	    	   mPaint.setStrokeWidth(5);
//	    	   canvas.drawLine(0, yPos, width, yPos, mPaint);
	       }
	       mPaint.reset();
	    }
	    
	    if( mHideAnimation ) 
	    {
	    	canvas.restoreToCount(saveCount);
	    }
	   
	}
 

/**
 * Inner render the canvas.
 * 
 * @param canvas
 */
private void innerRender(Canvas canvas) {
    if (!transform.isIdentity()) {
        // apply transform
        canvas.concat(transform);
    }

    // apply clipping path, if we have one
    if (clippingPath != null) {
        canvas.clipPath(clippingPath.getPath());
    }

    // setup transparency layer
    int alphaSaveCount = -1;
    if (opacity < 1.0F) {
        int alpha = (int) (opacity * 255);
        alphaSaveCount = canvas.saveLayerAlpha(new RectF(canvas.getClipBounds()), alpha,
                Canvas.HAS_ALPHA_LAYER_SAVE_FLAG);
    }

    // render content
    if (getPath() != null) {
        // Apply shadow outset
        if (shadow != null) {
            shadow.applyOutsetToPath(path, canvas);
        }
        // Set fill
        if (fillColor != null) {
            Paint fillPaint = ObjectPool.paintPool.checkOut();
            fillPaint.setStyle(Style.FILL);
            fillColor.applyFillToPath(path, fillPaint, canvas);
            // Check the paint back into the pool
            ObjectPool.paintPool.checkIn(fillPaint);
        }
        // Apply shadow insets
        if (shadow != null) {
            shadow.applyInsetToPath(path, canvas);
        }
        // Set stroke
        if (stroke != null) {
            // Passing a null paint. This will eventually be rendered as new
            // Paint with Paint.ANTI_ALIAS_FLAG.
            stroke.applyStrokeToPath(path, null, canvas);
        }
    }

    // Draw the children
    renderChildren(canvas);

    if (opacity < 1.0F) {
        canvas.restoreToCount(alphaSaveCount);
    }
    // Release the path after the rendering. Usually, this method will
    // render into a Picture, so no new Path will be created, unless a
    // complete redraw is performed after a Picture disposal.
    ObjectPool.pathPool.checkIn(path);
    path = null;
}