Android 图片截取人物头像(仿逗拍)

要求

根据给定的头部模板，截取资源图。

分析

定义剪切浮层，实现背景资源图的操作view

实现

• 绘制剪切浮层

/**
     * 初始化绘制笔
     */
    private void initRectPaint()
    {
        mFloatPaint = new Paint();
        mFloatPaint.setAlpha(mAlpha);
        mFloatPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.XOR));

        mEdgePaint = new Paint();
        mEdgePaint.setColor(Color.parseColor("#ff000000"));
        mEdgePaint.setAlpha(mAlpha);
    }


@Override
    public void draw(Canvas canvas)
    {

        /** 绘制周围的背景色 **/
        drawEdge(canvas);

        /** 绘制中间浮层 **/
        canvas.drawBitmap(mCropDrawable, mFloatRect.left, mFloatRect.top,
                mFloatPaint);

    }

• 操作图层手势

@Override
    protected void onDraw(Canvas canvas)
    {
        canvas.save();
        canvas.drawColor(Color.parseColor("#ff1c1c22"));
        canvas.drawBitmap(mBGHeadBitmap, mFloatRect.left, mFloatRect.top, null);
        canvas.drawBitmap(mBGBitmap, mBGgmatrix, null);
        mFloatView.draw(canvas);
        canvas.restore();
    }




//手势操作


public boolean onTouchEvent(MotionEvent event)
    {
        switch (event.getAction() & MotionEvent.ACTION_MASK)
        {
            case MotionEvent.ACTION_DOWN :
                eventMode = EventMode.DRAG;
                x_down = event.getX();
                y_down = event.getY();
                savedMatrix.set(mBGgmatrix);
                break;
            case MotionEvent.ACTION_POINTER_DOWN :
                eventMode = EventMode.ZOOM;
                oldDist = spacing(event);
                mRotation = rotation(event);
                savedMatrix.set(mBGgmatrix);
                midPoint(midPoint, event);
                break;
            case MotionEvent.ACTION_MOVE :

                if (eventMode == EventMode.DRAG)
                {
                    matrix1.set(savedMatrix);
                    matrix1.postTranslate(event.getX() - x_down, event.getY()
                            - y_down);
                    mBGgmatrix.set(matrix1);
                    invalidate();
                } else if (eventMode == EventMode.ZOOM)
                {

                    float rotation = rotation(event) - mRotation;
                    float newDist = spacing(event);
                    float scale = newDist / oldDist;

                    /** 缩放 **/
                    float values[] = new float[9];

                    {
                        matrix1.set(savedMatrix);
                        matrix1.postScale(scale, scale, midPoint.x, midPoint.y);
                    }

                    /** 旋转 **/
                    matrix1.postRotate(rotation, midPoint.x, midPoint.y);

                    mBGgmatrix.set(matrix1);

                    invalidate();
                }

                break;
            case MotionEvent.ACTION_UP :
            case MotionEvent.ACTION_POINTER_UP :

                eventMode = EventMode.NONE;
                break;
        }

        return true;
    }

• 获取剪切图片

        Bitmap tmpBitmap = Bitmap.createBitmap(mScrrenWidth, mScrrenHeight,
                Config.ARGB_8888); // 背景图片
        Canvas canvas = new Canvas(tmpBitmap); // 新建画布
        canvas.drawBitmap(mBGHeadBitmap, mFloatRect.left, mFloatRect.top, null);
        canvas.drawBitmap(mBGBitmap, mBGgmatrix, null); // 画图片
        canvas.save(Canvas.ALL_SAVE_FLAG); // 保存画布
        canvas.restore();

        Bitmap ret = Bitmap.createBitmap(tmpBitmap, mFloatRect.left,
                mFloatRect.top, mFloatRect.width(), mFloatRect.height(), null,
                true);
        tmpBitmap.recycle();
        tmpBitmap = null;

        Bitmap newRet = Bitmap.createBitmap(mFloatRect.width(),
                mFloatRect.height(), Config.ARGB_8888);

        Canvas canvasHead = new Canvas(newRet);
        canvasHead.drawBitmap(ret, 0, 0, null);
        Paint paintHead = new Paint();
        paintHead.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
        Bitmap crop = BitmapFactory.decodeResource(mContext.getResources(),
                R.drawable.headmask);

        canvasHead.drawBitmap(crop, 0, 0, paintHead);

        return newRet;

效果

***基本上我不提供源代码，但是我会尽量用文字把对应的算法描述清楚

****因为靠自己的努力和实践写出来的效果才真正是自己的东西

如果想要源码Demo，请联系我