Android实现控件点击波纹扩散效果

来源：互联网发布：linux cp命令编辑：程序博客网时间：2024/04/29 20:08
效果图

这里写图片描述
代码

public class MyButton extends android.support.v7.widget.AppCompatImageButton {    private static final String TAG = "MyButton";    public static final int INVALIDATE_DURATION = 15;//    每次扩散半径    public static int DIFUSE_GAP = 10;//    系统判定为长按事件的时间    private int longPressTimeout;    private Paint colofrPaint;    //背景颜色    private Paint bgPaint;//    按下的时间    private long downTime = 0;    private int eventX;    private int eventY;    private boolean isPushButton;//    当前半径    private int shaderRadio;//    最大半径    private int maxRadio;    private int viewwidth;    private int viewheight;    public MyButton(Context context) {        this(context,null);    }    public MyButton(Context context, AttributeSet attrs) {        super(context, attrs);        initPaint();//        系统判定长按的时间        longPressTimeout = ViewConfiguration.getLongPressTimeout();//500        Log.d(TAG, "MyButton: "+longPressTimeout);    }    public void initPaint(){        colofrPaint = new Paint(Paint.ANTI_ALIAS_FLAG);        bgPaint = new Paint(Paint.ANTI_ALIAS_FLAG);        colofrPaint.setColor(getResources().getColor(R.color.bottom_color));        bgPaint.setColor(getResources().getColor(R.color.reveal_color));    }    @Override    public boolean onTouchEvent(MotionEvent event) {        switch (event.getAction()) {            case MotionEvent.ACTION_DOWN:                if(downTime==0) {                    downTime = SystemClock.elapsedRealtime();                }                eventX = (int) event.getX();                eventY = (int) event.getY();                countMaxRatio();                isPushButton = true;                Log.d(TAG, "onTouchEvent: "+maxRadio);                postInvalidateDelayed(INVALIDATE_DURATION);                break;            case MotionEvent.ACTION_MOVE:                break;            case MotionEvent.ACTION_UP:                //判断是否是长按                if (SystemClock.elapsedRealtime() - downTime < longPressTimeout) {                    DIFUSE_GAP = 30;                    postInvalidate();                } else {                    clearData();                }                break;        }        return super.onTouchEvent(event);    }    @Override    protected void dispatchDraw(Canvas canvas) {        super.dispatchDraw(canvas);        if(!isPushButton)return;        //绘制按下后的背景        canvas.drawRect(0,0,viewwidth,viewheight,bgPaint);        canvas.save();        //绘制扩散圆背景        canvas.clipRect(0,0,viewwidth,viewheight);        Log.d(TAG, "dispatchDraw: "+shaderRadio);        canvas.drawCircle(eventX,eventY,shaderRadio,colofrPaint);        canvas.restore();        if(shaderRadio<maxRadio) {            postInvalidateDelayed(INVALIDATE_DURATION,0,0,viewwidth,viewheight);            shaderRadio += DIFUSE_GAP;        } else{            clearData();        }    }    //计算最大半径    public void countMaxRatio(){        if (viewwidth>viewheight) {            if(eventX<viewwidth/2){                maxRadio =  viewwidth - eventX;            } else{                maxRadio = eventX;            }        }else{            if (eventY < viewheight/2){                maxRadio = viewheight - eventY;            }else{                maxRadio = viewheight/2+eventY;            }        }    }    public void clearData(){        downTime = 0;        DIFUSE_GAP = 10;        isPushButton = false;        shaderRadio = 0;        postInvalidate();    }    @Override    protected void onSizeChanged(int w, int h, int oldw, int oldh) {        super.onSizeChanged(w, h, oldw, oldh);        viewwidth = w;        viewheight = h;    }}
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