先看效果图：
现在大部分的app上难免会使用到圆形头像，所以今天我给大家分享一个单独使用的，并且周围带有圆环动画的花哨圆形头像控件，本控件是在圆形头像控件基础上实现的，只是在其周围再画一些不同大小的圆而已，就可以实现如图的效果。
圆形头像的基本原理是将设置的资源文件转化成Bitmap,然后通过BitmapShader类将Bitmap成为Paint的渲染器，然后在onDraw()中通过canvas.drawCircle(rx,ry,radius,paint);画布上画圆，而这个圆就是形成了圆形头像。
在xml中通过src设置的资源文件在ImageView的setImageDrawable(drawable)方法中可以得到Drawable类型的图像，然后再将Drawable转成Bitmap就可以了
public void setImageDrawable(Drawable drawable) { super.setImageDrawable(drawable); mBitmap = getBitmapFromDrawable(drawable); setup(); } private Bitmap getBitmapFromDrawable(Drawable drawable) { if (drawable == null) { return null; } if (drawable instanceof BitmapDrawable) { //从bitmap中间裁剪出最大的正方形 Bitmap bitmap = ((BitmapDrawable) drawable).getBitmap(); return getMaxSquareCenter(bitmap); //return ((BitmapDrawable) drawable).getBitmap(); } try { Bitmap bitmap; if (drawable instanceof ColorDrawable) { bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG); } else { int min = Math.min(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight()); bitmap = Bitmap.createBitmap(min, min, BITMAP_CONFIG); } Canvas canvas = new Canvas(bitmap); int left,top,right,buttom; int width = canvas.getWidth(); int height = canvas.getHeight(); int abs = Math.abs(width - height); if(width <= height){ left = 0; top = (height - abs) / 2; right = width; buttom = height - top; }else{ left = (width - abs) / 2; top = 0; right = width - left; buttom = height; } //drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight()); drawable.setBounds(left, top, right, buttom); drawable.draw(canvas); return bitmap; } catch (OutOfMemoryError e) { return null; } } /** * 从bitmap中间裁剪出最大的正方形 * @param bitmap * @return */ private Bitmap getMaxSquareCenter(Bitmap bitmap){ int w = bitmap.getWidth(); // 得到图片的宽，高 int h = bitmap.getHeight(); int cropWidth = w >= h ? h : w;// 裁切后所取的正方形区域边长 return Bitmap.createBitmap(bitmap, (w - cropWidth)/2 , (h - cropWidth)/2, cropWidth, cropWidth, null, false); }
获取到Bitmap对象后就可以将Bitmap缩小一倍后，在将其画在画布上，这样就有地方来画周围的圆环了。
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 / 2; //将图片缩放在正中间 缩小一倍 dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f; } else { scale = mDrawableRect.width() / (float) mBitmapWidth / 2; //将图片缩放在正中间 缩小一倍 dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f; } mShaderMatrix.setScale(scale , scale ); //在x轴上平移mDrawableRadius，就在正中间了 mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth + mDrawableRadius, (int) (dy + 0.5f) + mBorderWidth); mBitmapShader.setLocalMatrix(mShaderMatrix); }
下面就是画图片周围的圆环了，就是在图片的外围画两个圆，一个半径大点，颜色浅点，一个半径小点，颜色深点就可以了，然后通过Handler通过延时操作，不断的改变两个圆的半径大小和颜色的深浅，重绘就可以了
private float mChangeRateBorder;//记录外圆执行动画时半径变化率 private float mChangeRateOuter;//记录内圆执行动画时半径变化率 private float mChangeRateInner;//记录图片边框执行动画时半径变化率 private float mChangeRange;//变化范围，View半径的1/6 //*******执行动画*******// //外圆执行动画时半径变化率 private float mRateOuter[] = { -1,-1,-1,-1,-1,-1,-1,-1,-1,-1, 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.88f,0.85f,0.82f,0.76f,0.72f,0.68f,0.60f,0.54f,0.48f, 0.40f,0.33f,0.28f,0.20f}; //内圆执行动画时半径变化率 private float mRateInner[] = { -1,-1,-1,-1,-1, 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.88f,0.84f,0.80f,0.72f,0.67f,0.60f,0.54f,0.48f,-1f ,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f}; //图片边框执行动画时半径变化率 private float mRateBorder[] = { 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.90f,0.84f,0.78f,0.72f,0.64f,0.58f,-1f,-1f,-1f ,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f ,-1f,-1f,-1f,-1f}; private int mRateIndex;//动画变化率的索引
Handler不断改变半径的变化率和画笔的颜色
/** * 按住执行动画 */ private Handler mHandler = new Handler(){ @Override public void handleMessage(Message msg) { super.handleMessage(msg); int index = mRateIndex ++; mChangeRateBorder = mRateBorder[(index)% mRateBorder.length]; setPaintCorlor(mBorderPaint,mChangeRateBorder,DEFAULT_BORDER_COLOR); setPaintAlpha(mBorderPaint,(index)% mRateBorder.length,mRateBorder); mChangeRateOuter = mRateOuter[(index) % mRateOuter.length]; setPaintCorlor(mOuterPaint,mChangeRateOuter,mOuterPaintColor); setPaintAlpha(mOuterPaint,(index) % mRateOuter.length,mRateOuter); mChangeRateInner = mRateInner[(index) % mRateInner.length]; setPaintCorlor(mInnerPaint,mChangeRateInner,mInnerPaintColor); setPaintAlpha(mInnerPaint,(index) % mRateInner.length,mRateInner); //System.out.println("---------mChangeRate:"+mChangeRateBorder); invalidate(); mHandler.removeCallbacksAndMessages(null); mHandler.sendEmptyMessageDelayed(0,30); } };
每执行一次handleMessage()就会触发（invalidate()）View重绘，onDraw中不断的重绘，只需改变每个Circle的半径即可
@Override protected void onDraw(Canvas canvas) { if (getDrawable() == null) { return; } //画动画的图形 canvas.drawCircle(getWidth() / 2,getHeight() / 2,getChangeRadiusOuter(mOuterRadius),mOuterPaint); canvas.drawCircle(getWidth() / 2,getHeight() / 2,getChangeRadiusInner(mInnerRadius),mInnerPaint); canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint); canvas.drawCircle(getWidth() / 2, getHeight() / 2, getChangeRadiusBorder(mBorderRadius), mBorderPaint); }
根据Handler中给的变化率来计算每个Circle的半径
private float getChangeRadiusBorder(float radius){ return mChangeRateBorder * mChangeRange + radius; } private float getChangeRadiusOuter(float radius){ return mChangeRateOuter * mChangeRange + radius; } private float getChangeRadiusInner(float radius){ return mChangeRateInner * mChangeRange + radius; }
这样在不断的向Handler发送消息时，也就会不断的触发重绘，不断改变外围圆的大小，形成上图所见的动画效果
如下四个方法，就是来控制圆环所展示的不同状态
/** * 开始动画 */ public void startAnim(){ //让外围的圆环动起来 mHandler.sendEmptyMessageDelayed(0,30); } /** * 停止动画 */ public void stopAnim(){ //停止外圆环的动画，展示默认的大小 mHandler.removeCallbacksAndMessages(null); mChangeRateBorder = 0; mChangeRateOuter = 0; mChangeRateInner = 0; initAnimColor(); enterAnim(); } /** * 进入动画 */ public void enterAnim(){ //展示外圆环，显示默认大小 mHandlerEnter.sendEmptyMessage(0); } /** * 退出动画 */ public void exitAnim(){ //隐藏外圆环 mHandlerExit.sendEmptyMessage(0); }
好了，动态头像到这基本就实现了，进入动画和退出动画的代码就不贴出来分析了，如果发现bug或者有任何意见欢迎留言。
完整源码
import android.content.Context; 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.os.Handler; import android.os.Message; import android.util.AttributeSet; import android.widget.ImageView; /** * Created by cj_28 on 2016/10/15. */ public class DynamicAvatarView extends ImageView { private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP; private static final int COLORDRAWABLE_DIMENSION = 1; private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888; private Bitmap mBitmap; private BitmapShader mBitmapShader; private final Matrix mShaderMatrix = new Matrix(); private final Paint mBitmapPaint = new Paint(); private final Paint mBorderPaint = new Paint(); private final Paint mOuterPaint = new Paint(); private final Paint mInnerPaint = new Paint(); private static final int DEFAULT_BORDER_WIDTH = 3; private static final int DEFAULT_BORDER_COLOR = Color.WHITE; private static final int OUTER_PAINT_COLOR = Color.parseColor("#55FFFFFF"); private static final int INNER_PAINT_COLOR = Color.parseColor("#66FFFFFF"); private int mBorderColor = DEFAULT_BORDER_COLOR; private int mBorderWidth = DEFAULT_BORDER_WIDTH; private int mOuterPaintColor = OUTER_PAINT_COLOR; private int mInnerPaintColor = INNER_PAINT_COLOR; private int mBitmapWidth; private int mBitmapHeight; private final RectF mDrawableRect = new RectF(); private final RectF mBorderRect = new RectF(); private float mDrawableRadius;//显示的图片 private float mBorderRadius;//..//显示的图片上的边框 private float mOuterRadius;//外层动画 private float mInnerRadius;//..//内层动画 private float mRealDrawableRadius;//这是View没有被缩放之前的mDrawableRadius的半径 private float mRealBorderRadius;//.. private boolean mReady; private boolean mSetupPending; private float mChangeRateBorder;//记录外圆执行动画时半径变化率 private float mChangeRateOuter;//记录内圆执行动画时半径变化率 private float mChangeRateInner;//记录图片边框执行动画时半径变化率 private float mChangeRange;//变化范围，View半径的1/6 //*******执行动画*******// //外圆执行动画时半径变化率 private float mRateOuter[] = { -1,-1,-1,-1,-1,-1,-1,-1,-1,-1, 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.88f,0.85f,0.82f,0.76f,0.72f,0.68f,0.60f,0.54f,0.48f, 0.40f,0.33f,0.28f,0.20f}; //内圆执行动画时半径变化率 private float mRateInner[] = { -1,-1,-1,-1,-1, 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.88f,0.84f,0.80f,0.72f,0.67f,0.60f,0.54f,0.48f,-1f ,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f}; //图片边框执行动画时半径变化率 private float mRateBorder[] = { 0,0.1f,0.2f,0.3f,0.4f,0.5f,0.6f,0.7f,0.8f,0.9f,1.0f ,0.92f,0.90f,0.84f,0.78f,0.72f,0.64f,0.58f,-1f,-1f,-1f ,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f,-1f ,-1f,-1f,-1f,-1f}; //private int mColor[] = {0x55FFFFFF,0x44FFFFFF,0x33FFFFFF,0x22FFFFFF,0x11FFFFFF,0x00FFFFFF,0x00FFFFFF,0x00FFFFFF,0x00FFFFFF,0x00FFFFFF}; private int mRateIndex;//动画变化率的索引 //*******进入动画*******// //外圆执行动画时半径变化率 private float mRateOuterEnter[] = { -2,-2,//外圆要缩小2个mChangeRange才会完全隐藏 -2,-2,-2,-2,-2, -0.8f,-0.6f,-0.4f,-0.2f,-0.1f, 0,0.1f,0.2f,0.3f,0.4f,0.5f ,0.44f,0.4f,0.35f,0.3f,0.25f ,0.20f,0.15f,0.1f,0.0f}; //内圆执行动画时半径变化率 private float mRateInnerEnter[] = { -1,-1,//外圆要缩小1个mChangeRange才会完全隐藏 -0.8f,-0.6f,-0.4f,-0.2f,-0.1f, 0,0.1f,0.2f,0.3f,0.35f,0.4f ,0.45f,0.5f,0.45f,0.4f,0.35f ,0.3f,0.25f,0.2f,0.15f,0.1f ,0.05f,0f,0f,0f}; private int mRateIndexEnter;//进入动画变化率的索引 //*******退出动画*******// //外圆执行动画时半径变化率 private float mRateOuterExit[] = { 0.0f,-0.2f,-0.4f,-0.6f,-0.8f ,-1f,-1.2f,-1.4f,-1.6f,-1.8f ,-2f}; //内圆执行动画时半径变化率 private float mRateInnerExit[] = { 0.0f,-0.1f,-0.2f,-0.3f,-0.4f ,-0.5f,-0.6f,-0.7f,-0.8f,-0.9f ,-1f}; private int mRateIndexExit;//进入动画变化率的索引 /** * 按住执行动画 */ private Handler mHandler = new Handler(){ @Override public void handleMessage(Message msg) { super.handleMessage(msg); int index = mRateIndex ++; mChangeRateBorder = mRateBorder[(index)% mRateBorder.length]; setPaintCorlor(mBorderPaint,mChangeRateBorder,DEFAULT_BORDER_COLOR); setPaintAlpha(mBorderPaint,(index)% mRateBorder.length,mRateBorder); mChangeRateOuter = mRateOuter[(index) % mRateOuter.length]; setPaintCorlor(mOuterPaint,mChangeRateOuter,mOuterPaintColor); setPaintAlpha(mOuterPaint,(index) % mRateOuter.length,mRateOuter); mChangeRateInner = mRateInner[(index) % mRateInner.length]; setPaintCorlor(mInnerPaint,mChangeRateInner,mInnerPaintColor); setPaintAlpha(mInnerPaint,(index) % mRateInner.length,mRateInner); //System.out.println("---------mChangeRate:"+mChangeRateBorder); invalidate(); mHandler.removeCallbacksAndMessages(null); mHandler.sendEmptyMessageDelayed(0,30); } }; private Handler mHandlerEnter = new Handler(){ @Override public void handleMessage(Message msg) { super.handleMessage(msg); int index = mRateIndexEnter ++; if(index >= mRateOuterEnter.length) { mRateIndexEnter = 0; mHandlerEnter.removeCallbacksAndMessages(null); return; } mChangeRateOuter = mRateOuterEnter[(index) % mRateOuterEnter.length]; mChangeRateInner = mRateInnerEnter[(index) % mRateInnerEnter.length]; invalidate(); mHandlerEnter.removeCallbacksAndMessages(null); mHandlerEnter.sendEmptyMessageDelayed(0,20); } }; private Handler mHandlerExit = new Handler(){ @Override public void handleMessage(Message msg) { super.handleMessage(msg); int index = mRateIndexExit ++; if(index >= mRateOuterExit.length) { mRateIndexExit = 0; mHandlerExit.removeCallbacksAndMessages(null); return; } mChangeRateOuter = mRateOuterExit[(index) % mRateOuterExit.length]; mChangeRateInner = mRateInnerExit[(index) % mRateInnerExit.length]; invalidate(); mHandlerExit.removeCallbacksAndMessages(null); mHandlerExit.sendEmptyMessageDelayed(0,20); } }; /** * 设置outer和inner的画笔颜色 * @param paint * @param rate * @param color */ private void setPaintCorlor(Paint paint,float rate,int color){ if(rate < 0){ paint.setColor(Color.TRANSPARENT); }else{ paint.setColor(color); } } /** * 设置透明度 * @param paint * @param index * @param rate */ private void setPaintAlpha(Paint paint,int index,float[] rate){ int pre = index -1; if(pre >= 0 ){ if(rate[pre] > rate[index] && rate[index] > 0){ int color = paint.getColor(); int colorTransparent = color & 0xff000000; int colorValue = color & 0x00ffffff; colorTransparent = colorTransparent >>> 7; paint.setColor((int)(rate[index] * colorTransparent) << 7 | colorValue); } } } public DynamicAvatarView(Context context) { this(context,null); } public DynamicAvatarView(Context context, AttributeSet attrs) { this(context, attrs,0); } public DynamicAvatarView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); super.setScaleType(SCALE_TYPE); //可以执行了 mReady = true; if (mSetupPending) { setup(); mSetupPending = false; } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int widthMode = MeasureSpec.getMode(widthMeasureSpec); int widthSize = MeasureSpec.getSize(widthMeasureSpec); int heightMode = MeasureSpec.getMode(heightMeasureSpec); int heightSize = MeasureSpec.getSize(heightMeasureSpec); int size = Math.min(widthSize, heightSize); super.onMeasure(MeasureSpec.makeMeasureSpec(size,widthMode), MeasureSpec.makeMeasureSpec(size,heightMode)); } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); enterAnim(); } @Override protected void onDraw(Canvas canvas) { if (getDrawable() == null) { return; } //画动画的图形 canvas.drawCircle(getWidth() / 2,getHeight() / 2,getChangeRadiusOuter(mOuterRadius),mOuterPaint); canvas.drawCircle(getWidth() / 2,getHeight() / 2,getChangeRadiusInner(mInnerRadius),mInnerPaint); canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint); canvas.drawCircle(getWidth() / 2, getHeight() / 2, getChangeRadiusBorder(mBorderRadius), mBorderPaint); } private float getChangeRadiusBorder(float radius){ return mChangeRateBorder * mChangeRange + radius; } private float getChangeRadiusOuter(float radius){ return mChangeRateOuter * mChangeRange + radius; } private float getChangeRadiusInner(float radius){ return mChangeRateInner * mChangeRange + radius; } private void initAnimColor(){ mOuterPaint.setStyle(Paint.Style.FILL); mOuterPaint.setAntiAlias(true); mOuterPaint.setColor(mOuterPaintColor); mInnerPaint.setStyle(Paint.Style.FILL); mInnerPaint.setAntiAlias(true); mInnerPaint.setColor(mInnerPaintColor); //图片边框（默认白色） mBorderPaint.setColor(mBorderColor); mOuterRadius = mRealBorderRadius / 6 * 5; mInnerRadius = mRealBorderRadius / 6 * 4; mChangeRange = mRealBorderRadius / 6; mRateIndex = 0; } /** * 开始动画 */ public void startAnim(){ mHandler.sendEmptyMessageDelayed(0,30); } /** * 停止动画 */ public void stopAnim(){ mHandler.removeCallbacksAndMessages(null); mChangeRateBorder = 0; mChangeRateOuter = 0; mChangeRateInner = 0; // mBorderPaint.setColor(DEFAULT_BORDER_COLOR); // mOuterPaint.setColor(mOuterPaintColor); // mInnerPaint.setColor(mInnerPaintColor); // mRateIndex = 0; initAnimColor(); //invalidate(); enterAnim(); } /** * 进入动画 */ public void enterAnim(){ mHandlerEnter.sendEmptyMessage(0); } /** * 退出动画 */ public void exitAnim(){ mHandlerExit.sendEmptyMessage(0); } /** * 设置外圆动画的颜色 * @param outerPaintColor */ public void setOuterPaintColor(int outerPaintColor) { if (outerPaintColor == mOuterPaintColor) { return; } mOuterPaintColor = outerPaintColor; mOuterPaint.setColor(mOuterPaintColor); invalidate(); } /** * 设置内圆动画的颜色 * @param innerPaintColor */ public void setInnerPaintColor(int innerPaintColor) { if (innerPaintColor == mInnerPaintColor) { return; } mInnerPaintColor = innerPaintColor; mInnerPaint.setColor(mInnerPaintColor); invalidate(); } /** * 设置图片边框的颜色 * @param borderColor */ public void setBorderColor(int borderColor) { if (borderColor == mBorderColor) { return; } mBorderColor = borderColor; mBorderPaint.setColor(mBorderColor); invalidate(); } /** * 设置图片边框的宽度 * @param borderWidth */ public void setBorderWidth(int borderWidth) { if (borderWidth == mBorderWidth) { return; } mBorderWidth = borderWidth; setup(); } @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 onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); //只有在此方法中调用setup，setup中的getWidth方法得到的值才不会是0， setup(); } @Override public void setImageBitmap(Bitmap bm) { super.setImageBitmap(bm); mBitmap = getMaxSquareCenter(bm); setup(); } /** * mxl中设置src就会走此方法 * @param drawable */ @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(); } /** * 从bitmap中间裁剪出最大的正方形 * @param bitmap * @return */ private Bitmap getMaxSquareCenter(Bitmap bitmap){ int w = bitmap.getWidth(); // 得到图片的宽，高 int h = bitmap.getHeight(); int cropWidth = w >= h ? h : w;// 裁切后所取的正方形区域边长 return Bitmap.createBitmap(bitmap, (w - cropWidth)/2 , (h - cropWidth)/2, cropWidth, cropWidth, null, false); } private Bitmap getBitmapFromDrawable(Drawable drawable) { if (drawable == null) { return null; } if (drawable instanceof BitmapDrawable) { //从bitmap中间裁剪出最大的正方形 Bitmap bitmap = ((BitmapDrawable) drawable).getBitmap(); return getMaxSquareCenter(bitmap); //return ((BitmapDrawable) drawable).getBitmap(); } try { Bitmap bitmap; if (drawable instanceof ColorDrawable) { bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG); } else { int min = Math.min(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight()); bitmap = Bitmap.createBitmap(min, min, BITMAP_CONFIG); } Canvas canvas = new Canvas(bitmap); int left,top,right,buttom; int width = canvas.getWidth(); int height = canvas.getHeight(); int abs = Math.abs(width - height); if(width <= height){ left = 0; top = (height - abs) / 2; right = width; buttom = height - top; }else{ left = (width - abs) / 2; top = 0; right = width - left; buttom = height; } //drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight()); drawable.setBounds(left, top, right, buttom); drawable.draw(canvas); return bitmap; } catch (OutOfMemoryError e) { return null; } } private void setup() { //只有执行过构造函数之后，所有的成员才被初始化完毕 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(); //图片边框设置的范围 mBorderRect.set(0, 0, getWidth(), getHeight()); mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2) / 2; mRealBorderRadius = 2 * mBorderRadius; //图片显示的范围 mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth); //让图片显示的范围是控件大小的一半 mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2) / 2; mRealDrawableRadius = 2 * mDrawableRadius; updateShaderMatrix(); initAnimColor(); 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 / 2; //将图片缩放在正中间 dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f; } else { scale = mDrawableRect.width() / (float) mBitmapWidth / 2; dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f; } mShaderMatrix.setScale(scale , scale ); mShaderMatrix.postTranslate((int) (dx + 0.5f) + mBorderWidth + mDrawableRadius, (int) (dy + 0.5f) + mBorderWidth); mBitmapShader.setLocalMatrix(mShaderMatrix); } }
参考：https://github.com/hdodenhof/CircleImageView
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查字典教程网。
【Android实现动态圆环的图片头像控件】相关文章：
★ Android 平台实现Gif 图像解码并播放代码及组件