在Android中实现正方形、彩色和圆边按钮？

public class SquareColorfulButton extends Button {
    private Paint paint;
    private int backgroundColor;
    private int borderColor;
    private int borderWidth;
    private int cornerRadius;

    public SquareColorfulButton(Context context) {
        super(context);
        init();
    }

    public SquareColorfulButton(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public SquareColorfulButton(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        paint = new Paint();
        paint.setAntiAlias(true);
        backgroundColor = Color.BLUE; // 设置默认背景颜色为蓝色
        borderColor = Color.WHITE; // 设置默认边框颜色为白色
        borderWidth = 2; // 设置默认边框宽度为2px
        cornerRadius = 10; // 设置默认圆角半径为10px
    }

    @Override
    protected void onDraw(Canvas canvas) {
        // 绘制背景
        paint.setColor(backgroundColor);
        canvas.drawRect(0, 0, getWidth(), getHeight(), paint);

        // 绘制边框
        paint.setColor(borderColor);
        paint.setStrokeWidth(borderWidth);
        paint.setStyle(Paint.Style.STROKE);
        canvas.drawRect(0, 0, getWidth(), getHeight(), paint);

        // 绘制文字
        super.onDraw(canvas);
    }

    // 设置背景颜色
    public void setBackgroundColor(int color) {
        backgroundColor = color;
        invalidate();
    }

    // 设置边框颜色
    public void setBorderColor(int color) {
        borderColor = color;
        invalidate();
    }

    // 设置边框宽度
    public void setBorderWidth(int width) {
        borderWidth = width;
        invalidate();
    }

    // 设置圆角半径
    public void setCornerRadius(int radius) {
        cornerRadius = radius;
        invalidate();
    }
}

<com.example.myapplication.SquareColorfulButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button"
    android:textColor="#FFFFFF"
    android:padding="10dp"
    app:backgroundColor="#FF0000"
    app:borderColor="#000000"
    app:borderWidth="2"
    app:cornerRadius="20" />