Android：调整customview的高度

Question

I have created a Circular customview as shown in screenShot.As you can see the lower part of the circle is sliced in the layout.How can i adjust its height. Here is the relevant code

CustomView.class

protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    float width = (float)getWidth();
    float height = (float)getHeight();
    float radius;
    if (width > height){
        radius = height/2;
    }else{
        radius = width/2;
    }

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

    Paint paint = new Paint();
    //change color of arc
    paint.setColor(Color.parseColor("#d50000"));
    paint.setStrokeWidth(5);
    paint.setFlags(Paint.ANTI_ALIAS_FLAG);
    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, 270, 270, false, paint);
}

layout.xml

<com.gosemathraj.CustomSemicircleUp
    android:layout_height="@dimen/semicircle" // 86dp
    android:layout_width="wrap_content" />

screenshot

Answer 1

You can try to wrap the CustomSemicircleUp inside a LinearLayout (or any layout) and then center the circle view, so the aspect ratio is kept for the original view:

<LinearLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent">

     <com.gosemathraj.CustomSemicircleUp
         android:layout_gravity="center"
         android:layout_height="@dimen/semicircle" // 86dp
         android:layout_width="wrap_content" />

</LinearLayout>

But the android:layout_width="wrap_content" is still problematic because of different screen sizes. You will then have get the screen width and set the height accordingly.