圆角矩形“RoundRectShape”使用详解

圆角矩形 常用作一些组件的背景

构造函数：

RoundRectShape(float[] outerRadii, RectF inset, float[] innerRadii)

Specifies an outer (round)rect and an optional inner (round)rect.// 指定一个外部（圆角）矩形 和 一个 可选的 内部（圆角）矩形。

Parameters:

outerRadii 

An
array of 8 radius values, for the outer roundrect. The first two floats
are for the top-left corner (remaining pairs correspond clockwise). For
no rounded corners on the outer
rectangle, pass null.

//一个包含8个弧度值，指定外部圆角矩形的 4个角部的弧度及 ：new float[] {l, l, t, t, r, r, b, b};

// 前2个 左上角， 3 4 ， 右上角， 56， 右下， 78 ，左下，如果没弧度的话，传入null即可。

inset 

A RectF that specifies the distance from the inner rect to each side of the outer rect. For no inner, pass null.

//指定外部矩形4条边 与内部矩形的4条边的个距离，也用RectF的方式指定。

innerRadii 

An
array of 8 radius values, for the inner roundrect. The first two floats
are for the top-left corner (remaining pairs correspond clockwise). For
no rounded corners on
the inner rectangle, pass null. If inset parameter is null, this parameter is ignored.

//同第一个参数。

例子如下：

package com.example.testroundrectshape;

import android.app.Activity;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.RoundRectShape;
import android.os.Bundle;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		TextView test = (TextView) findViewById(R.id.test);
		// 外部矩形弧度
		float[] outerR = new float[] { 8, 8, 8, 8, 8, 8, 8, 8 };
		// 内部矩形与外部矩形的距离
		RectF inset = new RectF(100, 100, 50, 50);
		// 内部矩形弧度
		float[] innerRadii = new float[] { 20, 20, 20, 20, 20, 20, 20, 20 };

		RoundRectShape rr = new RoundRectShape(outerR, inset, null);
		ShapeDrawable drawable = new ShapeDrawable(rr);
		//指定填充颜色
		drawable.getPaint().setColor(Color.YELLOW);
		// 指定填充模式
		drawable.getPaint().setStyle(Paint.Style.FILL);

		test.setBackgroundDrawable(drawable);

	}
}

效果图：