android - how i can get width and height dimension from my customview? -

i have custom view ...

package nan.salsa.goal.customview;  import android.r; import android.content.context; import android.graphics.canvas; import android.graphics.drawable.shapedrawable; import android.graphics.drawable.shapes.rectshape; import android.util.attributeset; import android.util.log; import android.view.view;  public class dayview extends view {      private static string tag="dayview";      private shapedrawable mdrawable;      public dayview(context context) {         super(context);     }      public dayview(context context, attributeset attrs) {         super(context, attrs);         init();     }      public dayview(context context, attributeset attrs, int defstyle) {         super(context, attrs, defstyle);         init();     }      public void init() {          int x = 10;         int y = 10;         int width = 300;         int height = 300;          mdrawable = new shapedrawable(new rectshape());         mdrawable.getpaint().setcolor(0xff74ac23);         mdrawable.setbounds(x, y, x + width, y + height);        }      @override     protected void ondraw(canvas canvas) {         // todo auto-generated method stub         super.ondraw(canvas);         setbackgroundcolor(r.color.black);         mdrawable.draw(canvas);      } } 

with simple configuration file :

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     android:orientation="vertical" android:layout_width="fill_parent"     android:layout_height="fill_parent" android:background="#e06f00">      <nan.salsa.goal.customview.dayview android:id="@+id/dayview"         android:layout_height="match_parent"          android:layout_width="fill_parent" />   </linearlayout> 

in view want dinamically set width of rectangle ...

i have tried :

    view parent = getparent();      int width = parent.getwidth();   

// throw nullpointerexception because parent null ...

and also:

          getrootview().getwidth(); 

// in case no null pointerexception method return 0:

how can ?

regards

antonio musella

by adding method custom view class:

    @override     public void onsizechanged (int w, int h, int oldw, int oldh){         super.onsizechanged(w, h, oldw, oldh);         screenw = w;         screenh = h;     }