【实例简介】

【实例截图】

【核心代码】

package davidzoomimageviewrounddemo.qq986945193.com.davidzoomimageviewrounddemo.view;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Bitmap;

import android.graphics.Canvas;

import android.graphics.Paint;

import android.graphics.PorterDuff;

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;

import davidzoomimageviewrounddemo.qq986945193.com.davidzoomimageviewrounddemo.R;

/**

* @author ：程序员小冰

* @新浪微博 ：http://weibo.com/mcxiaobing

* @CSDN博客: http://blog.csdn.net/qq_21376985

* @交流Qq ：986945193

* @GitHub:https://github.com/QQ986945193

*/

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(Bitmap.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(), Bitmap.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(PorterDuff.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);

}

}