以特定角度畫線（動態）

Question

我想繪製一個圓並且該活動必須接收值（以度爲單位）。我會在這個圈子上畫線，並有機會在上面畫點。

如果你能幫助我，這將是巨大的:)

Answer 1

我想這：

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); 
    } 
} 

但結果卻是2個圈screenshot
我爲UR新謝謝幫助:)