以特定角度画一条线（动态）

Question

我想绘制一个圆圈，该活动必须接收值（以度为单位）。我会在这个圆圈上绘制线条，并有机会在其上绘制点。

如果你可以帮助我，那就太棒了:)。

Answer 1

我试过了这个：

public class DiagObstActivity extends Activity {
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.diagobstacles_main);
    int radius;
    radius = 200;
    final ImageView imgCircle = (ImageView) findViewById(R.id.imgCircle);
     Paint paint = new Paint();
    paint.setColor(getResources().getColor((R.color.blue)));
    paint.setStyle(Paint.Style.STROKE);

    Bitmap bmp = Bitmap.createBitmap(500,500,Bitmap.Config.ARGB_4444);

    Canvas canvas = new Canvas(bmp);
    canvas.drawCircle(bmp.getWidth() / 2, bmp.getHeight() / 2, radius, paint);

    RectF rectF = new RectF(50, 20, 100, 80);
    canvas.drawOval(rectF, paint);
    paint.setColor(Color.BLACK);
    canvas.drawArc(rectF, 180, 0, true, paint);

    imgCircle.setImageBitmap(bmp);
  }
}

但结果是2个圈screenshot
我感谢您的帮助：）