Android之布局转圆角

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说明

很多需求比较无语，需要某个布局转圆角，像个显眼包一样，所以为了满足显眼包，必须整呐

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提示：以下是本篇文章正文内容，下面案例可供参考

一、效果图

说明：轮播图可以直接转圆角，图片也可以，我这里只是在轮播图外层嵌套了一个RoundRelativeLayout，直接对RoundRelativeLayout进行转角。

二、实现步骤

1.自定义RoundRelativeLayout

代码如下（示例）：

public class RoundRelativeLayout extends RelativeLayout {private final RectF roundRect = new RectF();private final Paint maskPaint = new Paint();private final Paint zonePaint = new Paint();private Context mContext;private float rect_adius = 20;  //圆角大小public RoundRelativeLayout(Context context) {super(context);init(context);}public RoundRelativeLayout(Context context, AttributeSet attrs) {super(context, attrs);init(context);}public RoundRelativeLayout(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);init(context);}private void init(Context context) {this.mContext = context;maskPaint.setAntiAlias(true);maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));zonePaint.setAntiAlias(true);zonePaint.setColor(Color.WHITE);}@Overrideprotected void onLayout(boolean changed, int left, int top, int right, int bottom) {super.onLayout(changed, left, top, right, bottom);int w = getWidth();int h = getHeight();roundRectSet(w, h);}@Overridepublic void draw(Canvas canvas) {canvasSetLayer(canvas);super.draw(canvas);canvas.restore();}/*** 从新设置圆角** @param adius*/public void setRectAdius(float adius) {rect_adius = adius;invalidate();}/*** 圆角区域设置** @param width* @param height*/private void roundRectSet(int width, int height) {roundRect.set(0, 0, width, height);}/*** 画布区域裁剪** @param canvas*/private void canvasSetLayer(Canvas canvas) {canvas.saveLayer(roundRect, zonePaint, Canvas.ALL_SAVE_FLAG);canvas.drawRoundRect(roundRect, rect_adius, rect_adius, zonePaint);//canvas.saveLayer(roundRect, maskPaint, Canvas.ALL_SAVE_FLAG);}
}

2.使用

说明：其实xml布局引用自定义这个就已经成功转角了，这里贴一下设置布局背景的代码，跟正常设置背景一样。

relative_back.setBackgroundColor(Color.parseColor("#ffffff"))

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总结

其实就是自定义RoundRelativeLayout进行转角，角度可设置，很简单。