Android自定义Drawable实现圆形和圆角

本文实例为大家分享了自定义drawable实现圆形和圆角的具体代码，供大家参考，具体内容如下

圆形

package com.customview.widget;

import android.graphics.bitmap;
import android.graphics.bitmapshader;
import android.graphics.canvas;
import android.graphics.colorfilter;
import android.graphics.paint;
import android.graphics.pixelformat;
import android.graphics.shader;
import android.graphics.drawable.drawable;
import android.support.annotation.intrange;
import android.support.annotation.nonnull;
import android.support.annotation.nullable;

/**
 * 自定义drawable 实现圆形图片
 * created by hust_twj on 2017/9/26.
 */

public class circledrawable extends drawable {
  private paint mpaint;
  private int mwidth; //宽/高，直径
  private bitmap mbitmap;

  public circledrawable(bitmap bitmap) {
    this.mbitmap = bitmap;
    bitmapshader bitmapshader = new bitmapshader(mbitmap, shader.tilemode.clamp, shader.tilemode.clamp);//着色器 水平和竖直都需要填充满
    mpaint = new paint();
    mpaint.setantialias(true);
    mpaint.setshader(bitmapshader);
    mwidth = math.min(mbitmap.getwidth(), mbitmap.getheight()); //宽高的最小值作为直径
  }

  @override
  public void draw(@nonnull canvas canvas) {
    canvas.drawcircle(mwidth/2, mwidth/2, mwidth/2, mpaint); //绘制圆形
  }

  @override
  public void setalpha(@intrange(from = 0, to = 255) int i) {
    mpaint.setalpha(i);
  }

  @override
  public void setcolorfilter(@nullable colorfilter colorfilter) {
    mpaint.setcolorfilter(colorfilter);
  }

  @override
  public int getopacity() {
    return pixelformat.translucent; //设置系统默认，让drawable支持和窗口一样的透明度
  }

  //还需要从重写以下2个方法，返回drawable实际宽高
  @override
  public int getintrinsicwidth() {
    return mwidth;
  }

  @override
  public int getintrinsicheight() {
    return mwidth;
  }


}

圆角：

package com.customview.widget;

import android.graphics.bitmap;
import android.graphics.bitmapshader;
import android.graphics.canvas;
import android.graphics.colorfilter;
import android.graphics.paint;
import android.graphics.pixelformat;
import android.graphics.rectf;
import android.graphics.shader;
import android.graphics.drawable.drawable;
import android.support.annotation.intrange;
import android.support.annotation.nonnull;
import android.support.annotation.nullable;

/**
 * 自定义drawable 实现圆角图片
 * created by hust_twj on 2017/9/26.
 */

public class roundcornerdrawable extends drawable {
  private paint mpaint;
  private rectf rectf;//定义矩形区域
  private bitmap mbitmap;

  public roundcornerdrawable(bitmap bitmap) {
    this.mbitmap = bitmap;
    bitmapshader bitmapshader = new bitmapshader(mbitmap, shader.tilemode.clamp, shader.tilemode.clamp);//着色器 水平和竖直都需要填充满
    mpaint = new paint();
    mpaint.setantialias(true);
    mpaint.setshader(bitmapshader);
    //rectf = new rectf(0, 0, bitmap.getwidth(), bitmap.getheight());
  }

  @override
  public void draw(@nonnull canvas canvas) {
    //rectf:圆角矩形区域
    canvas.drawroundrect(new rectf(0, 0, mbitmap.getwidth(), mbitmap.getheight()),100, 100, mpaint);//rx：x方向上的圆角半径; ry：y方向上的圆角半径。
  }

/*  @override
  public void setbounds(int left, int top, int right, int bottom) {
    super.setbounds(left, top, right, bottom);
    rectf = new rectf(left, top, right, bottom);
  }*/

  @override
  public void setalpha(@intrange(from = 0, to = 255) int i) {
    mpaint.setalpha(i);
  }

  @override
  public void setcolorfilter(@nullable colorfilter colorfilter) {
    mpaint.setcolorfilter(colorfilter);
  }

  @override
  public int getopacity() {
    return pixelformat.translucent; //设置系统默认，让drawable支持和窗口一样的透明度
  }

  //还需要从重写以下2个方法，返回drawable实际宽高
  @override
  public int getintrinsicwidth() {
    return mbitmap.getwidth();
  }

  @override
  public int getintrinsicheight() {
    return mbitmap.getheight();
  }

}

mainactivity中：

bitmap bitmap = bitmapfactory.decoderesource(getresources(), r.drawable.xxx);
imageview.setimagedrawable(new roundcornerdrawable(bitmap));

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。