Android 设置图片为圆角或者圆形

亦凉 2022-10-15 11:59 26阅读 0赞

自己写了一个工具类，使用自定义view，设置图片为圆角，当rect\_adius=100时，圆角就会变成圆形

public class RoundImageView extends AppCompatImageView {
        private final RectF roundRect = new RectF();
        private float rect_adius = 10;
        private final Paint maskPaint = new Paint();
        private final Paint zonePaint = new Paint();
    
        public RoundImageView(Context context, AttributeSet attrs) {
            super(context, attrs);
            TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RoundImageView);
            //根据属性名称获取对应的值，属性名称的格式为类名_属性名
            rect_adius = typedArray.getFloat(R.styleable.RoundImageView_rect_adius, 10f);
            init();
        }
    
        public RoundImageView(Context context) {
            super(context);
            init();
        }
    
        private void init() {
            maskPaint.setAntiAlias(true);
            maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
            zonePaint.setAntiAlias(true);
            zonePaint.setColor(Color.WHITE);
            float density = getResources().getDisplayMetrics().density;
            rect_adius = rect_adius * density;
        }
    
        public void setRectAdius(float adius) {
            rect_adius = adius;
            invalidate();
        }
    
        @Override
        protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
            super.onLayout(changed, left, top, right, bottom);
            int w = getWidth();
            int h = getHeight();
            roundRect.set(0, 0, w, h);
        }
    
        @Override
        public void draw(Canvas canvas) {
            canvas.saveLayer(roundRect, zonePaint, Canvas.ALL_SAVE_FLAG);
            canvas.drawRoundRect(roundRect, rect_adius, rect_adius, zonePaint);
            canvas.saveLayer(roundRect, maskPaint, Canvas.ALL_SAVE_FLAG);
            super.draw(canvas);
            canvas.restore();
    
        }
    }

在styles中添加

<declare-styleable name="RoundImageView">
            <attr name="rect_adius" format="float" />
        </declare-styleable>