如何在弧的边缘添加小圆。
并且它也应该在时钟方向上以弧形边缘移动
现在我通过改变扫掠角度成功地为弧设置动画
还有黑点。
下面是getView和动画类的代码
--- init method and implement constructor ----
mRectF = new RectF(mWidth / 2 - 360, mHeight / 2 - 360, mWidth / 2 + 360, mHeight / 2 + 360);
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//draw circle background
mPaint.setColor(getResources().getColor(R.color.timer_background_color));
canvas.drawCircle(mWidth / 2, mHeight / 2, 360, mPaint);
mPaint.setColor(getResources().getColor(R.color.actionbar_back_color));
canvas.drawArc(mRectF, mStartAnagle, mSweepAngle, false, mPaint);
}
public class TimerAnimation extends Animation{
public TimerAnimation (float startAngle, float sweepAngle, long duration) {
mStartAnagle = startAngle;
mSweepAngle = sweepAngle;
setDuration(duration);
setRepeatCount(Animation.INFINITE);
setInterpolator(new LinearInterpolator());
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
if (!isComplete) {
mSweepAngle = mSweepAngle + 6;
if (mSweepAngle >= 360) {
isComplete = true;
mSweepAngle = 360;
}
} else {
mStartAnagle = mStartAnagle + 6;
mSweepAngle = mSweepAngle - 6;
if (mStartAnagle >= 360)
mStartAnagle = 0;
if (mStartAnagle == 270 || mSweepAngle <= 0) {
isComplete = false;
mSweepAngle = 0;
}
}
invalidate();
}
}
答案 0 :(得分:3)
也许您应该使用Path
:
Path path = new Path();
// Set the starting position of the path to (0,0).
path.moveTo(0, 0);
path.arcTo(...); //draw your arc here
path.circleTo(); //draw a small circle here at the end of arc
也许你应该calc the arc's end position并用作小圈子的中心。
答案 1 :(得分:2)
第1步:计算黑点的位置
建议中心位置是(centerX,centerY),黑点的位置是(x,y),然后,
x = radius * cos(mStartAnagle+mSweepAngle) + centerX;
y = radius * sin(mStartAnagle+mSweepAngle) + centerY;
第2步:绘制黑点
建议点图像为R.drawable.dot
,
Bitmap bitmap = BitmapFactory.decodeResource(getResources(),R.drawable.dot)
.copy(Bitmap.Config.ARGB_8888, true);
canvas.drawBitmap(bitmap, x, y, null);