自定义圆形的ImageVIew

/** * 圆形ImageView */public class CircleImageView extends ImageView {    private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;      //只允许CENTER_CROP模式    private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;  //默认创建的格式    private static final int COLORDRAWABLE_DIMENSION = 2;   //对于 colorDrawable 的大小    //以下是自定义属性    private int mBorderWidth = 3;            //默认边框的宽度，单位 dp    private int mBorderColor = 0xFFFF0000;   //默认边框的颜色    private int mFillColor = 0x00000000;     //纯色的填充色    private boolean mBorderOverlay = false;  //true表示边框会覆盖一部分图片，false表示边框不会覆盖在图片之上    //以下是成员变量    private final Matrix mShaderMatrix = new Matrix();  //对图片缩放的矩阵    private final Paint mBitmapPaint = new Paint();     //图片的画笔    private final Paint mBorderPaint = new Paint();     //边框的画笔    private final Paint mFillPaint = new Paint();       //背景色的画笔    private Bitmap mBitmap;            //设置的图片    private float mBorderRadius;       //边框的半径，默认向内部偏移了 mBorderWidth/2 的长度，保证边框不超出有效绘画区域    private float mDrawableRadius;     //内容的绘制半径，自动根据 mBorderOverlay 参数决定是否包括边框的半径    private ColorFilter mColorFilter;  //滤色    private boolean mSetupPending;     //是否执行了setUp方法    public CircleImageView(Context context) {        this(context, null);    }    public CircleImageView(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public CircleImageView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        mBorderWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, mBorderWidth, getResources().getDisplayMetrics());        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);        mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_civBorderWidth, mBorderWidth);        mBorderColor = a.getColor(R.styleable.CircleImageView_civBorderColor, mBorderColor);        mBorderOverlay = a.getBoolean(R.styleable.CircleImageView_civBorderOverlay, mBorderOverlay);        mFillColor = a.getColor(R.styleable.CircleImageView_civFillColor, mFillColor);        a.recycle();        super.setScaleType(SCALE_TYPE);    }    @Override    protected void onSizeChanged(int w, int h, int oldw, int oldh) {        super.onSizeChanged(w, h, oldw, oldh);        mSetupPending = true;        setup();    }    private void setup() {        if (!mSetupPending || getWidth() == 0 && getHeight() == 0) return;        if (mBitmap == null) {            invalidate();            return;        }        BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);        mBitmapPaint.setAntiAlias(true);        mBitmapPaint.setShader(bitmapShader);        mBorderPaint.setStyle(Paint.Style.STROKE);        mBorderPaint.setAntiAlias(true);        mBorderPaint.setColor(mBorderColor);        mBorderPaint.setStrokeWidth(mBorderWidth);        mFillPaint.setStyle(Paint.Style.FILL);        mFillPaint.setAntiAlias(true);        mFillPaint.setColor(mFillColor);        int drawableWidth = getWidth() - getPaddingLeft() - getPaddingRight();        int drawableHeight = getHeight() - getPaddingTop() - getPaddingBottom();        mDrawableRadius = Math.min(drawableWidth, drawableHeight) / 2;        mBorderRadius = mDrawableRadius - mBorderWidth / 2;        if (!mBorderOverlay) {            mDrawableRadius -= mBorderWidth;        }        int bitmapHeight = mBitmap.getHeight();        int bitmapWidth = mBitmap.getWidth();        float dx = (drawableWidth - mDrawableRadius * 2) / 2 + getPaddingLeft();        float dy = (drawableHeight - mDrawableRadius * 2) / 2 + getPaddingTop();        float scale;        mShaderMatrix.set(null);        if (bitmapWidth > bitmapHeight) {            scale = mDrawableRadius * 2 / bitmapHeight;            //图片的宽高比 大于 有效绘制区域的宽高比，此时缩放比以 高度的缩放比为基准            dx += (mDrawableRadius * 2 - bitmapWidth * scale) / 2; //dx 为负值，表示向左平移        } else {            scale = mDrawableRadius * 2 / bitmapWidth;             //图片的宽高比 小于 有效绘制区域的宽高比，此时缩放比以 宽度的缩放比为基准            dy += (mDrawableRadius * 2 - bitmapHeight * scale) / 2;//dy 为负值，表示向上平移        }        mShaderMatrix.postScale(scale, scale);   //设置图片的缩放大小        mShaderMatrix.postTranslate((int) (dx + 0.5f), (int) (dy + 0.5f)); //设置图片的平移距离        bitmapShader.setLocalMatrix(mShaderMatrix);  //最后赋值给BitmapShader        invalidate();    }    /**     * 没有调用父类的 super 方法，全完靠自定义控件绘制出来     */    @Override    protected void onDraw(Canvas canvas) {        if (mBitmap != null)            canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mDrawableRadius, mBitmapPaint);//绘制图片        else if (mFillColor != Color.TRANSPARENT)            canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mDrawableRadius, mFillPaint);  //绘制纯色背景        if (mBorderWidth != 0)            canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mBorderRadius, mBorderPaint);  //绘制边框    }    /**     * 将传入的drawable转换成bitmap     */    private Bitmap getBitmapFromDrawable(Drawable drawable) {        if (drawable == null) return null;        if (drawable instanceof BitmapDrawable) return ((BitmapDrawable) drawable).getBitmap();        try {            Bitmap bitmap;            if (drawable instanceof ColorDrawable) {                bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);            } else {                bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);            }            Canvas canvas = new Canvas(bitmap);            drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());            drawable.draw(canvas);            return bitmap;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }    @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    public void setAdjustViewBounds(boolean adjustViewBounds) {        if (adjustViewBounds) {            throw new IllegalArgumentException("adjustViewBounds not supported.");        }    }    @Override    public void setImageBitmap(Bitmap bm) {        super.setImageBitmap(bm);        mBitmap = bm;        setup();    }    @Override    public void setImageDrawable(Drawable drawable) {        super.setImageDrawable(drawable);        mBitmap = getBitmapFromDrawable(drawable);        setup();    }    @Override    public void setImageResource(@DrawableRes int resId) {        super.setImageResource(resId);        mBitmap = getBitmapFromDrawable(getDrawable());        setup();    }    @Override    public void setImageURI(Uri uri) {        super.setImageURI(uri);        mBitmap = uri != null ? getBitmapFromDrawable(getDrawable()) : null;        setup();    }    @Override    public void setColorFilter(ColorFilter cf) {        if (cf == mColorFilter) return;        mColorFilter = cf;        mBitmapPaint.setColorFilter(mColorFilter);        invalidate();    }    @Override    public void setPadding(int left, int top, int right, int bottom) {        super.setPadding(left, top, right, bottom);        setup();    }    public int getBorderColor() {        return mBorderColor;    }    public void setBorderColor(@ColorInt int borderColor) {        if (borderColor == mBorderColor) return;        mBorderColor = borderColor;        mBorderPaint.setColor(mBorderColor);        invalidate();    }    public void setBorderColorResource(@ColorRes int borderColorRes) {        setBorderColor(getContext().getResources().getColor(borderColorRes));    }    public int getFillColor() {        return mFillColor;    }    public void setFillColor(@ColorInt int fillColor) {        if (fillColor == mFillColor) return;        mFillColor = fillColor;        mFillPaint.setColor(fillColor);        invalidate();    }    public void setFillColorResource(@ColorRes int fillColorRes) {        setFillColor(getContext().getResources().getColor(fillColorRes));    }    public int getBorderWidth() {        return mBorderWidth;    }    public void setBorderWidth(int borderWidth) {        if (borderWidth == mBorderWidth) return;        mBorderWidth = borderWidth;        setup();    }    public boolean isBorderOverlay() {        return mBorderOverlay;    }    public void setBorderOverlay(boolean borderOverlay) {        if (borderOverlay == mBorderOverlay) return;        mBorderOverlay = borderOverlay;        setup();    }}