Android开发库VUtils之圆形头像CircleImageView

开发android也有很长的一段时间了，突然觉得android开发可以更简单，很多时候我们总是重复的做着一些事，比如自定义dialog，网络访问，圆形头像等。也许我们可以把他们封成一个库？用的时候直接拿过来，或稍加修改。那么，从今天开始，我要把我在项目中用到的融进VUtils，让android开发变的更简单！

圆形头像的实现网上代码已经很多，主要用到的技术是PorterDuffXfermode类，通过Paint的setXfermode方法设置并产生效果。（还不知道如何混合的，请看大神怎么说：aige的自定义View系列）

效果图：

package com.v.vutils.views;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.ImageView;

public class CircleImageView extends ImageView {

private Bitmap mask;
private Paint paint;
private Paint mBorderPaint;
private int mBorderWidth = 2;
private int mBorderColor = Color.BLUE;

public CircleImageView(Context paramContext) {
super(paramContext);
}

public CircleImageView(Context paramContext, AttributeSet paramAttributeSet) {
this(paramContext, paramAttributeSet, 0);
}

public CircleImageView(Context context, AttributeSet paramAttributeSet, int paramInt) {
super(context, paramAttributeSet, paramInt);
//        TypedArray a = context.obtainStyledAttributes(paramAttributeSet, R.styleable.CircularImage);
//        mBorderColor = a.getColor(R.styleable.CircularImage_border_color, mBorderColor);
//        float density = context.getResources().getDisplayMetrics().density; // 获取屏幕密度
//        mBorderWidth = a.getDimensionPixelOffset(R.styleable.CircularImage_border_width, 0);
//        a.recycle();
}

private boolean useDefaultStyle = false;

public void setUseDefaultStyle(boolean useDefaultStyle) {
this.useDefaultStyle = useDefaultStyle;
}

@Override
protected void onDraw(Canvas canvas) {
if (useDefaultStyle) {
super.onDraw(canvas);
return;
}

Drawable drawable = getDrawable();
if (drawable == null) {
super.draw(canvas);
return;
}

/**
* 第一种方法，使用图层进行图片混合
*/
Drawable localDrawable = editDrawable(drawable);
drawCircleImage(canvas, localDrawable);

/**
* 第二种方法，创建新的画布，并在该画布上进行混合,生成混合后的bitmap，
* 再将该bitmap画回到该View的原画布上
*/
//        Bitmap src = ((BitmapDrawable) drawable).getBitmap();
//        Bitmap bitmap = createCircleImage(src);
//        canvas.drawBitmap(bitmap, 0, 0, null);

// 对圆形图像进行描边
drawBorder(canvas, getWidth(), getHeight());
}

private void drawCircleImage(Canvas canvas, Drawable localDrawable) {
canvas.saveLayer(0, 0, getWidth(), getHeight(), null, Canvas.ALL_SAVE_FLAG);
localDrawable.draw(canvas);

if (mask == null)
mask = createOvalBitmap(getWidth(), getHeight());

if (this.paint == null) {
final Paint localPaint = new Paint();
localPaint.setFilterBitmap(false);
localPaint.setAntiAlias(true);
// 关键！DST_IN具体情况请查阅官方文档
localPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
this.paint = localPaint;
}
canvas.drawBitmap(mask, 0, 0, paint);
canvas.restore();
}

private void drawBorder(Canvas canvas, final int width, final int height) {
if (mBorderWidth == 0) {
return;
}

if (mBorderPaint == null) {
mBorderPaint = new Paint();
mBorderPaint.setStyle(Paint.Style.STROKE);
mBorderPaint.setAntiAlias(true);
mBorderPaint.setColor(mBorderColor);
mBorderPaint.setStrokeWidth(mBorderWidth);
}

RectF rectF = new RectF(0 + mBorderWidth, 0 + mBorderWidth,
width - mBorderWidth, height - mBorderWidth);
canvas.drawOval(rectF, mBorderPaint);

}

private Drawable editDrawable(Drawable localDrawable) {
int drawableWidth = localDrawable.getIntrinsicWidth();
int drawableHeight = localDrawable.getIntrinsicHeight();
Log.i("xxx", "" + drawableWidth + "," + drawableHeight);
final int width = getWidth();
final int height = getHeight();
Log.i("xxx", "" + width + "," + height);
float rw = (float) drawableWidth / (float) w
d537
idth;
float rh = (float) drawableHeight / (float) height;
int dWidth;
int dHeight;
if (rw < rh) {
dWidth = width;
dHeight = (int) (drawableHeight / rw);
//移动到中间的偏移量
int yOff = (dHeight - height) / 2;
localDrawable.setBounds(0, -yOff, dWidth, dHeight - yOff);
} else {
dWidth = (int) (drawableWidth / rh);
dHeight = height;
int xOff = (dWidth - width) / 2;
localDrawable.setBounds(-xOff, 0, dWidth - xOff, dHeight);
}
return localDrawable;
}

/**
* 创建圆形画布
*
* @param width
* @param height
* @return
*/
public Bitmap createOvalBitmap(final int width, final int height) {
Bitmap localBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas localCanvas = new Canvas(localBitmap);
Paint localPaint = new Paint();
localPaint.setColor(Color.GREEN);
localPaint.setAntiAlias(true); // 很重要！设置抗锯齿
int padding = mBorderWidth;
RectF localRectF = new RectF(padding, padding, width - padding, height - padding);
localCanvas.drawOval(localRectF, localPaint);

return localBitmap;
}

private Bitmap createCircleImage(Bitmap source) {
Bitmap target = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);
/**
* 产生一个同样大小的画布
*/
Canvas canvas = new Canvas(target);
final Paint paint = new Paint();
paint.setAntiAlias(true);
/**
* 首先绘制圆形
*/
int padding = mBorderWidth;
RectF localRectF = new RectF(padding, padding, getWidth() - padding, getHeight() - padding);
canvas.drawOval(localRectF, paint);
/**
* 使用SRC_IN
*/
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
/**
* 绘制图片
*/
int sourceWidth = source.getWidth();
int sourceHeight = source.getHeight();
Log.i("xxx", "sourceWidth:" + sourceWidth + ",sourceHeight:" + sourceHeight);
final int width = getWidth();
final int height = getHeight();
Log.i("xxx", "width:" + width + ",height:" + height);
float rw = (float) sourceWidth / (float) width;
float rh = (float) sourceHeight / (float) height;
int dWidth;
int dHeight;
if (rw < rh) {
dWidth = width;
dHeight = (int) (sourceHeight / rw);
//移动到中间的偏移量
int yOff = (dHeight - height) / 2;
canvas.drawBitmap(source, new Rect(0, 0, sourceWidth, sourceHeight),
new Rect(0, -yOff, dWidth, dHeight - yOff), paint);

} else {
dWidth = (int) (sourceWidth / rh);
dHeight = height;
int xOff = (dWidth - width) / 2;
canvas.drawBitmap(source, new Rect(0, 0, sourceWidth, sourceHeight),
new Rect(-xOff, 0, dWidth - xOff, dHeight), paint);
}
Log.i("xxx", "dWidth:" + dWidth + ",dHeight:" + dHeight);

return target;
}
}

在xml文件中直接使用：

<!--圆形-->
<com.v.vutils.views.CircleImageView
android:layout_width="300dp"
android:layout_height="300dp"
android:src="@drawable/img1" />
<!--椭圆-->
<com.v.vutils.views.CircleImageView
android:layout_width="300dp"
android:layout_height="400dp"
android:src="@drawable/img1" />

注意，图像在onDraw过程中会对图像做压缩，居中处理，如有特殊需求请自行修改或留言。