android自定义view仿照MIUI中音量控制效果

@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();
}
}