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Android开发之制作圆形头像自定义View,直接引用工具类，加快开发速度。带有源代码学习

大家都知道。现在好多头像都是圆形的，不再是以前的正方形或者长方形。

因此今天给大家带来的就是如何制作一个圆形头像。下面是效果图： 当然利用一个自定义View集成ImageView即可。

package com.qq986945193.zoomimageviewrounddemo;import android.content.Context;import android.content.res.TypedArray;import android.graphics.Bitmap;import android.graphics.Bitmap.Config;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.PorterDuff.Mode;import android.graphics.PorterDuffXfermode;import android.graphics.Rect;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.graphics.drawable.NinePatchDrawable;import android.util.AttributeSet;import android.widget.ImageView;/** * 微博：http://weibo.com/mcxiaobing * ============================================================================ * Copyright (c) 2015-2016 QQ986945193 All rights reserved. * ---------------------------------------------------------------------------- * 类名：自定义圆形头像View * ---------------------------------------------------------------------------- * 功能描述：http://blog.csdn.net/qq_21376985 * ---------------------------------------------------------------------------- */public class RoundImageView extends ImageView {
        private int mBorderThickness = 0;    private Context mContext;    private int defaultColor = 0xFFFFFFFF;    // 如果只有其中一个有值，则只画一个圆形边框    private int mBorderOutsideColor = 0;// 图片的外边界    private int mBorderInsideColor = 0;// 图片的内边界    // 控件默认长、宽    private int defaultWidth = 0;    private int defaultHeight = 0;    public RoundImageView(Context context) {        super(context);        mContext = context;    }    public RoundImageView(Context context, AttributeSet attrs) {        super(context, attrs);        mContext = context;        setCustomAttributes(attrs);    }    public RoundImageView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        mContext = context;        setCustomAttributes(attrs);    }    private void setCustomAttributes(AttributeSet attrs) {        TypedArray a = mContext.obtainStyledAttributes(attrs,                R.styleable.RoundImageView);        // 边界的宽度        mBorderThickness = a.getDimensionPixelSize(                R.styleable.RoundImageView_border_thickness, 0);        // 外边界的颜色        mBorderOutsideColor = a.getColor(                R.styleable.RoundImageView_border_outside_color, defaultColor);        // 内边界的颜色        mBorderInsideColor = a.getColor(                R.styleable.RoundImageView_border_inside_color, defaultColor);    }    @Override    protected void onDraw(Canvas canvas) {        Drawable drawable = getDrawable();        if (drawable == null) {            return;        }        if (getWidth() == 0 || getHeight() == 0) {            return;        }        this.measure(0, 0);        if (drawable.getClass() == NinePatchDrawable.class)            return;        Bitmap b = ((BitmapDrawable) drawable).getBitmap();        Bitmap bitmap = b.copy(Config.ARGB_8888, true);        if (defaultWidth == 0) {            defaultWidth = getWidth();        }        if (defaultHeight == 0) {            defaultHeight = getHeight();        }        // 保证重新读取图片后不会因为图片大小而改变控件宽、高的大小（针对宽、高为wrap_content布局的imageview，但会导致margin无效）        // if (defaultWidth != 0 && defaultHeight != 0) {
            // LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(        // defaultWidth, defaultHeight);        // setLayoutParams(params);        // }        int radius = 0;        if (mBorderInsideColor != defaultColor                && mBorderOutsideColor != defaultColor) {
    // 定义画两个边框，分别为外圆边框和内圆边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - 2 * mBorderThickness;            // 画内圆            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderInsideColor);            // 画外圆            drawCircleBorder(canvas, radius + mBorderThickness                    + mBorderThickness / 2, mBorderOutsideColor);        } else if (mBorderInsideColor != defaultColor                && mBorderOutsideColor == defaultColor) {
    // 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderInsideColor);        } else if (mBorderInsideColor == defaultColor                && mBorderOutsideColor != defaultColor) {
    // 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderOutsideColor);        } else {
    // 没有边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2;        }        Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);        canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight                / 2 - radius, null);    }    /** * 获取裁剪后的圆形图片 * * http://blog.csdn.net/qq_21376985 * @param radius * 半径 */    public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {        Bitmap scaledSrcBmp;        int diameter = radius * 2;        // 为了防止宽高不相等，造成圆形图片变形，因此截取长方形中处于中间位置最大的正方形图片        int bmpWidth = bmp.getWidth();        int bmpHeight = bmp.getHeight();        int squareWidth = 0, squareHeight = 0;        int x = 0, y = 0;        Bitmap squareBitmap;        if (bmpHeight > bmpWidth) {
    // 高大于宽            squareWidth = squareHeight = bmpWidth;            x = 0;            y = (bmpHeight - bmpWidth) / 2;            // 截取正方形图片            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,                    squareHeight);        } else if (bmpHeight < bmpWidth) {
    // 宽大于高            squareWidth = squareHeight = bmpHeight;            x = (bmpWidth - bmpHeight) / 2;            y = 0;            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,                    squareHeight);        } else {            squareBitmap = bmp;        }        if (squareBitmap.getWidth() != diameter                || squareBitmap.getHeight() != diameter) {            scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,                    diameter, true);        } else {            scaledSrcBmp = squareBitmap;        }        Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),                scaledSrcBmp.getHeight(), Config.ARGB_8888);        Canvas canvas = new Canvas(output);        Paint paint = new Paint();        Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),                scaledSrcBmp.getHeight());        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        canvas.drawARGB(0, 0, 0, 0);        canvas.drawCircle(scaledSrcBmp.getWidth() / 2,                scaledSrcBmp.getHeight() / 2, scaledSrcBmp.getWidth() / 2,                paint);        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));        canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);        // bitmap回收(recycle导致在布局文件XML看不到效果)        // bmp.recycle();        // squareBitmap.recycle();        // scaledSrcBmp.recycle();        bmp = null;        squareBitmap = null;        scaledSrcBmp = null;        return output;    }    /** * 边缘画圆 * * http://blog.csdn.net/qq_21376985 */    private void drawCircleBorder(Canvas canvas, int radius, int color) {        Paint paint = new Paint();        /* 去锯齿 */        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        paint.setColor(color);        /* 设置paint的　style　为STROKE：空心 */        paint.setStyle(Paint.Style.STROKE);        /* 设置paint的外框宽度 */        paint.setStrokeWidth(mBorderThickness);        canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);    }}

然后我们需要在布局中引用。下面是布局的一个引用，其实很简单，就和咱们

引用自定义View一模一样。由于它继承了ImageView。所以，方法大致相同。

当然还有，我们写了一个样式，所以需要在styles样式中添加：

OK,这样，圆形的的效果就能出来了，是不是很简单呢？当然，自定义View那一块想了解的可以深入。毕竟，你只会用，看不懂源代码也是不太好吧？是不是呢？

（Eclipse版本）源代码传送门： （Android Studio版本）源代码传送门：