android图片处理之让图片变成圆形

这几天做项目，有些地方的图片需要用到圆形图片，所以百度了一下，在github上找到一个开源项目，处理很简单，效果如下：

 

使用起来特别简单，一共三步，具体如下：

 1、创建一个java类circleimageview把下面的代码复制过去，报错的导包

package de.hdodenhof.circleimageview;
import edu.njupt.zhb.main.r;
import android.content.context;
import android.content.res.typedarray;
import android.graphics.bitmap;
import android.graphics.bitmapshader;
import android.graphics.canvas;
import android.graphics.color;
import android.graphics.matrix;
import android.graphics.paint;
import android.graphics.rectf;
import android.graphics.shader;
import android.graphics.drawable.bitmapdrawable;
import android.graphics.drawable.colordrawable;
import android.graphics.drawable.drawable;
import android.util.attributeset;
import android.widget.imageview;

public class circleimageview extends imageview {

  private static final scaletype scale_type = scaletype.center_crop;

  private static final bitmap.config bitmap_config = bitmap.config.argb_8888;
  private static final int colordrawable_dimension = 1;

  private static final int default_border_width = 0;
  private static final int default_border_color = color.black;

  private final rectf mdrawablerect = new rectf();
  private final rectf mborderrect = new rectf();

  private final matrix mshadermatrix = new matrix();
  private final paint mbitmappaint = new paint();
  private final paint mborderpaint = new paint();

  private int mbordercolor = default_border_color;
  private int mborderwidth = default_border_width;

  private bitmap mbitmap;
  private bitmapshader mbitmapshader;
  private int mbitmapwidth;
  private int mbitmapheight;

  private float mdrawableradius;
  private float mborderradius;

  private boolean mready;
  private boolean msetuppending;

  public circleimageview(context context) {
    super(context);
  }

  public circleimageview(context context, attributeset attrs) {
    this(context, attrs, 0);
  }

  public circleimageview(context context, attributeset attrs, int defstyle) {
    super(context, attrs, defstyle);
    super.setscaletype(scale_type);

    typedarray a = context.obtainstyledattributes(attrs, r.styleable.circleimageview, defstyle, 0);

    mborderwidth = a.getdimensionpixelsize(r.styleable.circleimageview_border_width, default_border_width);
    mbordercolor = a.getcolor(r.styleable.circleimageview_border_color, default_border_color);

    a.recycle();

    mready = true;

    if (msetuppending) {
      setup();
      msetuppending = false;
    }
  }

  @override
  public scaletype getscaletype() {
    return scale_type;
  }

  @override
  public void setscaletype(scaletype scaletype) {
    if (scaletype != scale_type) {
      throw new illegalargumentexception(string.format("scaletype %s not supported.", scaletype));
    }
  }

  @override
  protected void ondraw(canvas canvas) {
    if (getdrawable() == null) {
      return;
    }

    canvas.drawcircle(getwidth() / 2, getheight() / 2, mdrawableradius, mbitmappaint);
    canvas.drawcircle(getwidth() / 2, getheight() / 2, mborderradius, mborderpaint);
  }

  @override
  protected void onsizechanged(int w, int h, int oldw, int oldh) {
    super.onsizechanged(w, h, oldw, oldh);
    setup();
  }

  public int getbordercolor() {
    return mbordercolor;
  }

  public void setbordercolor(int bordercolor) {
    if (bordercolor == mbordercolor) {
      return;
    }

    mbordercolor = bordercolor;
    mborderpaint.setcolor(mbordercolor);
    invalidate();
  }

  public int getborderwidth() {
    return mborderwidth;
  }

  public void setborderwidth(int borderwidth) {
    if (borderwidth == mborderwidth) {
      return;
    }

    mborderwidth = borderwidth;
    setup();
  }

  @override
  public void setimagebitmap(bitmap bm) {
    super.setimagebitmap(bm);
    mbitmap = bm;
    setup();
  }

  @override
  public void setimagedrawable(drawable drawable) {
    super.setimagedrawable(drawable);
    mbitmap = getbitmapfromdrawable(drawable);
    setup();
  }

  @override
  public void setimageresource(int resid) {
    super.setimageresource(resid);
    mbitmap = getbitmapfromdrawable(getdrawable());
    setup();
  }

  private bitmap getbitmapfromdrawable(drawable drawable) {
    if (drawable == null) {
      return null;
    }

    if (drawable instanceof bitmapdrawable) {
      return ((bitmapdrawable) drawable).getbitmap();
    }

    try {
      bitmap bitmap;

      if (drawable instanceof colordrawable) {
        bitmap = bitmap.createbitmap(colordrawable_dimension, colordrawable_dimension, bitmap_config);
      } else {
        bitmap = bitmap.createbitmap(drawable.getintrinsicwidth(), drawable.getintrinsicheight(), bitmap_config);
      }

      canvas canvas = new canvas(bitmap);
      drawable.setbounds(0, 0, canvas.getwidth(), canvas.getheight());
      drawable.draw(canvas);
      return bitmap;
    } catch (outofmemoryerror e) {
      return null;
    }
  }

  private void setup() {
    if (!mready) {
      msetuppending = true;
      return;
    }

    if (mbitmap == null) {
      return;
    }

    mbitmapshader = new bitmapshader(mbitmap, shader.tilemode.clamp, shader.tilemode.clamp);

    mbitmappaint.setantialias(true);
    mbitmappaint.setshader(mbitmapshader);

    mborderpaint.setstyle(paint.style.stroke);
    mborderpaint.setantialias(true);
    mborderpaint.setcolor(mbordercolor);
    mborderpaint.setstrokewidth(mborderwidth);

    mbitmapheight = mbitmap.getheight();
    mbitmapwidth = mbitmap.getwidth();

    mborderrect.set(0, 0, getwidth(), getheight());
    mborderradius = math.min((mborderrect.height() - mborderwidth) / 2, (mborderrect.width() - mborderwidth) / 2);

    mdrawablerect.set(mborderwidth, mborderwidth, mborderrect.width() - mborderwidth, mborderrect.height() - mborderwidth);
    mdrawableradius = math.min(mdrawablerect.height() / 2, mdrawablerect.width() / 2);

    updateshadermatrix();
    invalidate();
  }

  private void updateshadermatrix() {
    float scale;
    float dx = 0;
    float dy = 0;

    mshadermatrix.set(null);

    if (mbitmapwidth * mdrawablerect.height() > mdrawablerect.width() * mbitmapheight) {
      scale = mdrawablerect.height() / (float) mbitmapheight;
      dx = (mdrawablerect.width() - mbitmapwidth * scale) * 0.5f;
    } else {
      scale = mdrawablerect.width() / (float) mbitmapwidth;
      dy = (mdrawablerect.height() - mbitmapheight * scale) * 0.5f;
    }

    mshadermatrix.setscale(scale, scale);
    mshadermatrix.posttranslate((int) (dx + 0.5f) + mborderwidth, (int) (dy + 0.5f) + mborderwidth);

    mbitmapshader.setlocalmatrix(mshadermatrix);
  }

}

2、在values文件夹下面创建一个xlm文件attrs.xml把下面的代码复制进去

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <declare-styleable name="circleimageview">
    <attr name="border_width" format="dimension" />
    <attr name="border_color" format="color" />
  </declare-styleable>
</resources>

3、接下来就是使用了，直接在布局文件中使用，具体使用如下：

直接创建一个自定义的circleimageview   src属性设置你要改变成圆形的图片

<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="#ff00ff"
   >

<com.example.circleimageview.circleimageview 
  android:id="@+id/imageview"
  android:layout_width="100dp"
  android:layout_height="100dp"
  android:layout_centerinparent="true"
  android:src="@drawable/control_image"
  />
</relativelayout>

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。