@Override

    protected void onDraw(Canvas canvas) {

        float cx = getMeasuredWidth() / 2;

        float cy = getMeasuredHeight() / 2;

        r1 = cx - w1 / 2;

        r2 = cx - w1 / 2 - w2 / 2;

        r3 = cx - w1 / 2 - w2;

        // 绘制外圆

        paint.setStrokeWidth(w1);

        paint.setColor(Color.parseColor("#454547"));

        canvas.drawCircle(cx, cy, r1, paint);

        // 绘制中间圆环

        paint.setColor(Color.parseColor("#747476"));

        paint.setStrokeWidth(w2);

        canvas.drawCircle(cx, cy, r2, paint);

        // 绘制内圆

        paint.setColor(Color.parseColor("#464648"));

        paint.setStyle(Style.FILL);

        canvas.drawCircle(cx, cy, r3, paint);

        // 绘制中间的图片

        canvas.drawBitmap(bitmap, cx - bitmap.getWidth() / 2,

                cx - bitmap.getHeight() / 2, paint);

        // 绘制文本

        paint.setColor(Color.WHITE);

        paint.setStrokeWidth(0);

        paint.setTextSize(40);

        float textWidth = paint.measureText("铃声"); // 测量字体宽度，我们需要根据字体的宽度设置在圆环中间

        canvas.drawText("铃声", cx - textWidth / 2, cx + bitmap.getHeight() / 2

                + 40, paint);

        // 绘制进度

        paint.setStyle(Style.STROKE);

        paint.setStrokeWidth(w2);

        paint.setColor(Color.WHITE);

        RectF oval = new RectF(cx - r2, cy - r2, cx + r2, cy + r2); // 用于定义的圆弧的形状和大小的界限

        canvas.drawArc(oval, 270, 360 * progress / 100, false, paint);

        super.onDraw(canvas);

    }

public class VolumnController {

    Toast t;

    VolumnView tv;

    Context context;

    public VolumnController(Context context) {

        this.context = context;

    }

    public void show(float progress) {

        if (t == null) {

            t = new Toast(context);

            View layout = LayoutInflater.from(context).inflate(R.layout.vv,

                    null);

            tv = (VolumnView) layout.findViewById(R.id.volumnView1);

            t.setView(layout);

            t.setGravity(Gravity.BOTTOM, 0, 100);

            t.setDuration(Toast.LENGTH_SHORT);

        }

        tv.setProgress(progress);

        t.show();

    }

}