视觉要求改变字体大小，背景的圆角按照百分比改变

 RoundedCornerHelper 控制

public class RoundedCornerHelper {
    private Paint paint;
    private RectF rectF;
    private float cornerRadiusPercentage = 0.5f; // 默认 50%
    private float calculatedRadius;
    private int backgroundColor = 0x99636363; // 默认颜色

    public RoundedCornerHelper(Context context, AttributeSet attrs) {
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        rectF = new RectF();

        if (attrs != null) {
            TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.PercentageRoundedView);
            cornerRadiusPercentage = a.getFloat(R.styleable.PercentageRoundedView_cornerRadiusPercentage, cornerRadiusPercentage);
            backgroundColor = a.getColor(R.styleable.PercentageRoundedView_backgroundColor, backgroundColor);
            a.recycle();
        }

        paint.setColor(backgroundColor);
    }

    public void onSizeChanged(int width, int height) {
        calculatedRadius = Math.min(width, height) * cornerRadiusPercentage;
    }

    public void onDraw(Canvas canvas, View view) {
        rectF.set(0, 0, view.getWidth(), view.getHeight());
        canvas.drawRoundRect(rectF, calculatedRadius, calculatedRadius, paint);
    }

    public void setCornerRadiusPercentage(float percentage, View view) {
        cornerRadiusPercentage = Math.max(0f, Math.min(percentage, 1f));
        calculatedRadius = Math.min(view.getWidth(), view.getHeight()) * cornerRadiusPercentage;
        view.invalidate();
    }

    public void setBackgroundColorCustom(int color, View view) {
        backgroundColor = color;
        paint.setColor(backgroundColor);
        view.invalidate();
    }

    public int getBackgroundColorCustom() {
        return backgroundColor;
    }

    public float getCornerRadiusPercentage() {
        return cornerRadiusPercentage;
    }
}

 

PercentageRoundedTextView 实现

public class PercentageRoundedTextView extends android.support.v7.widget.AppCompatTextView {


    private RoundedCornerHelper roundedCornerHelper;

    public PercentageRoundedTextView(Context context) {
        super(context);
        init(null);
    }

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

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

    private void init(AttributeSet attrs) {
        roundedCornerHelper = new RoundedCornerHelper(getContext(), attrs);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        roundedCornerHelper.onSizeChanged(w, h);
        super.onSizeChanged(w, h, oldw, oldh);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        roundedCornerHelper.onDraw(canvas, this);
        super.onDraw(canvas);
    }

    // 提供设置方法
    public void setCornerRadiusPercentage(float percentage) {
        roundedCornerHelper.setCornerRadiusPercentage(percentage, this);
    }

    public void setBackgroundColorCustom(int color) {
        roundedCornerHelper.setBackgroundColorCustom(color, this);
    }

    public int getBackgroundColorCustom() {
        return roundedCornerHelper.getBackgroundColorCustom();
    }

    public float getCornerRadiusPercentage() {
        return roundedCornerHelper.getCornerRadiusPercentage();
    }
}