how to draw a half circle in android

this is how i created my semi circle in a drawable xml file.

<size
    android:width="180dp"
    android:height="90dp"></size>

<corners
    android:topLeftRadius="200dp"
    android:topRightRadius="200dp"></corners>


I would suggest to draw it through code.

1- Create class MyView and put below code.

public class MyView extends View {

    public MyView(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

    @Override
    protected void onDraw(Canvas canvas) {

        // TODO Auto-generated method stub
        super.onDraw(canvas);
        float width = (float) getWidth();
        float height = (float) getHeight();
        float radius;

        if (width > height) {
         radius = height / 4;
        } else {
         radius = width / 4;
        }

        Path path = new Path();
        path.addCircle(width / 2,
         height / 2, radius,
         Path.Direction.CW);

        Paint paint = new Paint();
        paint.setColor(Color.BLACK);
        paint.setStrokeWidth(5);
        paint.setStyle(Paint.Style.FILL);

        float center_x, center_y;
        final RectF oval = new RectF();
        paint.setStyle(Paint.Style.STROKE);

        center_x = width / 2;
        center_y = height / 2;

        oval.set(center_x - radius,
            center_y - radius,
            center_x + radius,
            center_y + radius);
        canvas.drawArc(oval, 90, 180, false, paint);
    }
}

2-Initialize this class inside you activity or fragment:-

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new MyView(this));
}

Your can use a rectangle shape .xml file and edit the corners on one side only.

Example:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <size android:height="30dp"
        android:width="30dp"/>
    <solid android:color="@color/black"/>
    <corners android:topLeftRadius="15dp"
        android:bottomLeftRadius="15dp"/>
</shape>

You can use <clip /> drawable in order to cut-off part of your circle.

http://developer.android.com/guide/topics/resources/drawable-resource.html#Clip

Tags:

Android