ScratchView 介绍
ScratchView。这是一个Android刮奖效果控件。
实现效果：
示例代码:
绘制出刮层效果
package com.clock.scratch;
import ...;
/**
* Created by Clock on 2016/8/26.
*/
public class ScratchView extends View {
...
public ScratchView(Context context) {
super(context);
TypedArray typedArray = context.obtainStyledAttributes(R.styleable.ScratchView);
init(typedArray);
}
...
private void init(TypedArray typedArray) {
...
mMaskColor = typedArray.getColor(R.styleable.ScratchView_maskColor, DEFAULT_MASKER_COLOR);
mMaskPaint = new Paint();
mMaskPaint.setAntiAlias(true);//抗锯齿
mMaskPaint.setDither(true);//防抖
setMaskColor(mMaskColor);
...
}
/**
* 设置蒙板颜色
*
* @param color 十六进制颜色值，如：0xffff0000（不透明的红色）
*/
public void setMaskColor(int color) {
mMaskPaint.setColor(color);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(mMaskBitmap, 0, 0, mBitmapPaint);//绘制图层遮罩
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
createMasker(w, h);
}
/**
* 创建蒙层
*
* @param width
* @param height
*/
private void createMasker(int width, int height) {
mMaskBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
mMaskCanvas = new Canvas(mMaskBitmap);
Rect rect = new Rect(0, 0, width, height);
mMaskCanvas.drawRect(rect, mMaskPaint);//绘制生成和控件大小一致的遮罩 Bitmap
}
}
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="ScratchView">
<!--蒙层的颜色-->
<attr name="maskColor" format="color|reference" />
</declare-styleable>
</resources>