Android四个圆角的ImageView

最新推荐文章于 2025-07-29 12:38:50 发布

mahongy

最新推荐文章于 2025-07-29 12:38:50 发布

阅读量1.9k

点赞数 1

CC 4.0 BY-SA版权

文章标签： Android ImageView圆角

本文链接：https://blog.youkuaiyun.com/mahongy/article/details/90693666

项目中需实现四个圆角的ImageView，经参考后找到适合自己项目的方法。代码中默认圆角半径为18，可按需调整。此方法仅作为工作记录，方便后续查询。

项目中有用到四个圆角的ImageView，在各种参考之后，找到了一种适合自己项目的方法，话不多讲，直接上代码：

public class RoundImageView extends AppCompatImageView {
    private int radius = 18; // 圆角半径
    private int diameter = radius << 1; // 圆角直径
    private Paint paint;
    private Path path;

    public RoundImageView(Context context) {
        super(context);
        initPaint();
    }

    public RoundImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initPaint();
    }

    public RoundImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        initPaint();
    }

    private void initPaint() {
        path = new Path();
        paint = new Paint();
        paint.setColor(Color.WHITE);
        paint.setAntiAlias(true);// 消除锯齿
    }

    @Override
    public void draw(Canvas canvas) {
        super.draw(canvas);
        drawLeftTop(canvas);
        drawRightTop(canvas);
        drawLeftBottom(canvas);
        drawRightBottom(canvas);
    }

    private void drawLeftTop(Canvas canvas) {
        path.moveTo(0, radius);
        path.lineTo(0, 0);
        path.lineTo(radius, 0);
        path.arcTo(new RectF(0, 0, diameter, diameter), -90, -90);
        path.close();
        canvas.drawPath(path, paint);
    }

    private void drawRightTop(Canvas canvas) {
        path.moveTo(getWidth(), radius);
        path.lineTo(getWidth(), 0);
        path.lineTo(getWidth() - radius, 0);
        path.arcTo(new RectF(getWidth() - diameter, 0, getWidth(), diameter), -90, 90);
        path.close();
        canvas.drawPath(path, paint);
    }

    private void drawLeftBottom(Canvas canvas) {
        path.moveTo(0, getHeight() - radius);
        path.lineTo(0, getHeight());
        path.lineTo(radius, getHeight());
        path.arcTo(new RectF(0,getHeight() - diameter, diameter, getHeight()), 90, 90);
        path.close();
        canvas.drawPath(path, paint);
    }

    private void drawRightBottom(Canvas canvas) {
        path.moveTo(getWidth() - radius, getHeight());
        path.lineTo(getWidth(), getHeight());
        path.lineTo(getWidth(), getHeight() - radius);
        RectF oval = new RectF(getWidth() - diameter, getHeight() - diameter, getWidth(), getHeight());
        path.arcTo(oval, 0, 90);
        path.close();
        canvas.drawPath(path, paint);
    }
}

代码中，默认圆角的半径为18，要借鉴的小伙伴可根据需求自行调整。

该方法可能对很多项目都不使用，它仅作为自己的工作记录，方便以后查询。