android 自定义圆角头像以及使用declare-styleable进行配置属性解析由于最新项目中正在检查UI是否与效果图匹配，结果关于联系人模块给的默认图片是四角稍带弧度的圆角，而我们截取的图片是正方形的，现在要给应用统一替换。

应用中既用到大圆角头像（即整个头像是圆的）又用到四角稍带弧度的圆角头像，封装一下以便重用。

以下直接见代码[java] view plain copy 在CODE上查看代码片派生到我的代码片package com.test.demo;import com.test.demo.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.Matrix;import android.graphics.Paint;import android.graphics.RectF;import android.graphics.Shader.TileMode;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.os.Parcelable;import android.util.AttributeSet;import android.util.Log;import android.util.TypedValue;import android.widget.ImageView;/*** 圆角imageview*/public class RoundImageView extends ImageView {private static final String TAG = "RoundImageView";/*** 图片的类型，圆形or圆角*/private int type;public static final int TYPE_CIRCLE = 0;public static final int TYPE_ROUND = 1;/*** 圆角大小的默认值*/private static final int CORNER_RADIUS_DEFAULT = 10;/*** 圆角的大小*/private int mCornerRadius;/*** 绘图的Paint*/private Paint mBitmapPaint;// 按下状态颜色private Paint mPressedColorPaint;private int pressedColor;/*** 圆角的半径*/private int mRadius;/*** 3x3 矩阵，主要用于缩小放大*/private Matrix mMatrix;/*** view的宽度*/private int mWidth;private RectF mRoundRect;public RoundImageView(Context context, AttributeSet attrs) {super(context, attrs);mMatrix = new Matrix();mBitmapPaint = new Paint();mBitmapPaint.setAntiAlias(true);TypedArray a = context.obtainStyledAttributes(attrs,R.styleable.RoundImageView);pressedColor = a.getColor(R.styleable.RoundImageView_pressed_color, -1);if (pressedColor != -1) {mPressedColorPaint = new Paint();mPressedColorPaint.setAntiAlias(true);mPressedColorPaint.setColor(pressedColor);}mCornerRadius = a.getDimensionPixelSize(R.styleable.RoundImageView_corner_radius, (int) TypedValue.applyDimension(PLEX_UNIT_DIP,CORNER_RADIUS_DEFAULT, getResources().getDisplayMetrics()));// 默认为10dp type = a.getInt(R.styleable.RoundImageView_type, TYPE_CIRCLE);// 默认为Circlea.recycle();}public RoundImageView(Context context) {this(context, null);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec);/*** 如果类型是圆形，则强制改变view的宽高一致，以小值为准*/if (type == TYPE_CIRCLE) {mWidth = Math.min(MeasureSpec.getSize(widthMeasureSpec),MeasureSpec.getSize(heightMeasureSpec));mRadius = mWidth / 2;}}/*** 初始化BitmapShader*/private void setUpShader() {Drawable drawable = getDrawable();if (drawable == null) {return;}Bitmap bmp = drawableToBitamp(drawable);// 将bmp作为着色器，就是在指定区域内绘制bmp// 渲染图像，使用图像为绘制图形着色BitmapShader mBitmapShader = new BitmapShader(bmp, TileMode.CLAMP,TileMode.CLAMP);float scale = 1.0f;if (type == TYPE_CIRCLE) {// 拿到bitmap宽或高的小值int bSize = Math.min(bmp.getWidth(), bmp.getHeight());scale = mWidth * 1.0f / bSize;} else if (type == TYPE_ROUND) {if (!(bmp.getWidth() == getWidth() && bmp.getHeight() == getHeight())) {// 如果图片的宽或者高与view的宽高不匹配，计算出需要缩放的比例；缩放后的图片的宽高，一定要大于我们view的宽高；所以我们这里取大值；scale = Math.max(getWidth() * 1.0f / bmp.getWidth(),getHeight() * 1.0f / bmp.getHeight());}}// shader的变换矩阵，我们这里主要用于放大或者缩小mMatrix.setScale(scale, scale);// 设置变换矩阵mBitmapShader.setLocalMatrix(mMatrix);// 设置shadermBitmapPaint.setShader(mBitmapShader);}@Overrideprotected void onDraw(Canvas canvas) {if (getDrawable() == null) {return;}setUpShader();if (type == TYPE_ROUND) {canvas.drawRoundRect(mRoundRect, mCornerRadius, mCornerRadius,mBitmapPaint);if (isPressed() && mPressedColorPaint != null) {canvas.drawRoundRect(mRoundRect, mCornerRadius, mCornerRadius,mPressedColorPaint);}} else {canvas.drawCircle(mRadius, mRadius, mRadius, mBitmapPaint);if (isPressed() && mPressedColorPaint != null) {canvas.drawCircle(mRadius, mRadius, mRadius, mPressedColorPaint);}}}@Overrideprotected void onSizeChanged(int w, int h, int oldw, int oldh) {super.onSizeChanged(w, h, oldw, oldh);Log.d(TAG, "onSizeChanged,w=" + w + ",h=" + h + ",oldw=" + oldw+ ",oldh=" + oldh);// 圆角图片的范围if (type == TYPE_ROUND) {mRoundRect = new RectF(0, 0, w, h);}}/*** drawable转bitmap*/private Bitmap drawableToBitamp(Drawable drawable) {if (drawable instanceof BitmapDrawable) {BitmapDrawable bd = (BitmapDrawable) drawable;return bd.getBitmap();}int w = drawable.getIntrinsicWidth();int h = drawable.getIntrinsicHeight();Bitmap bitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);Canvas canvas = new Canvas(bitmap);drawable.setBounds(0, 0, w, h);drawable.draw(canvas);return bitmap;}private static final String STATE_INSTANCE = "state_instance";private static final String STATE_TYPE = "state_type";private static final String STATE_BORDER_RADIUS = "state_border_radius"; private static final String STATE_PRESSED_COLOR = "state_pressed_color";@Overrideprotected Parcelable onSaveInstanceState() {Bundle bundle = new Bundle();bundle.putParcelable(STA TE_INSTANCE, super.onSaveInstanceState());bundle.putInt(STA TE_TYPE, type);bundle.putInt(STA TE_BORDER_RADIUS, mCornerRadius);bundle.putInt(STA TE_PRESSED_COLOR, pressedColor);return bundle;}@Overrideprotected void onRestoreInstanceState(Parcelable state) {if (state instanceof Bundle) {Bundle bundle = (Bundle) state;super.onRestoreInstanceState(((Bundle) state).getParcelable(STATE_INSTANCE));this.type = bundle.getInt(STATE_TYPE);this.mCornerRadius = bundle.getInt(STA TE_BORDER_RADIUS);this.pressedColor = bundle.getInt(STA TE_PRESSED_COLOR);if (pressedColor != -1) {mPressedColorPaint = new Paint();mPressedColorPaint.setAntiAlias(true);mPressedColorPaint.setColor(pressedColor);}} else {super.onRestoreInstanceState(state);}}public void setType(int type) {if (this.type != type) {this.type = type;if (this.type != TYPE_ROUND && this.type != TYPE_CIRCLE) {this.type = TYPE_CIRCLE;}requestLayout();}}@Overrideprotected void dispatchSetPressed(boolean pressed) {// imageView.setClickable(true),或imageView.setOnClickListener时才可触发dispatchSetPressedsuper.dispatchSetPressed(pressed);invalidate();}}declare-styleable：declare-styleable是给自定义控件添加自定义属性用的。