android - 在android圆圈内绘制文字

Question

public static Bitmap drawCircle(int width,int height, int borderWidth) {
    Bitmap canvasBitmap = Bitmap.createBitmap( 350, 350, Bitmap.Config.ARGB_8888);
    BitmapShader shader = new BitmapShader(canvasBitmap, TileMode.CLAMP, TileMode.CLAMP);
    Paint paint = new Paint();
    paint.setAntiAlias(true);
    paint.setShader(shader);
    paint.setShader(null);
    paint.setStyle(Paint.Style.STROKE);
    paint.setColor(Color.WHITE);
    paint.setStrokeWidth(borderWidth);

    Paint paint1 = new Paint();
    paint1.setAntiAlias(true);
    paint1.setShader(shader);
    paint1.setShader(null);
    paint1.setStyle(Paint.Style.STROKE);
    paint1.setColor(Color.WHITE);
    paint1.setStrokeWidth(borderWidth); 
    Canvas canvas = new Canvas(canvasBitmap);
    float radius = width > height ? ((float) height) / 2f : ((float) width) / 2f;
    //canvas.drawCircle(width / 2, height / 2, radius - borderWidth / 2, paint);
    final RectF rect = new RectF();
    rect.set(100, 100, 300, 300); 
    canvas.drawArc(rect, 270, 90, false, paint1);
    canvas.drawText("25%", 100, 100, 100, 100, paint1);
    return canvasBitmap;
}

如何在圆弧内绘制文本？我在 drawtext 中得到 IndexOutOfBoundException...我应该传递什么参数？我怎样才能让它进入弧线？

Answer 1

你可以试试这个。

    private Paint paint;
    private Paint circlePaint;

    paint = new Paint();
    circlePaint = new Paint();

    paint.setColor(Color.WHITE);
    paint.setTextSize(18f);
    paint.setAntiAlias(true);
    paint.setTextAlign(Paint.Align.CENTER);

    Rect bounds = new Rect();
    paint.getTextBounds(text, 0, text.length(), bounds);

    circlePaint.setColor(Color.RED);
    circlePaint.setAntiAlias(true);

    canvas.drawCircle(-3, 15 - (bounds.height() / 2), bounds.width() + 5, circlePaint);

    canvas.drawText(text, -3, 15, paint);

注意:(-3,15) 是绘制文本的起始坐标，(+5) 是填充。

这应该会为您提供类似通知标志的输出 ->