Android Custom View (v) view.requestlayout () and Invalidate ()

One. Points

1. If in the course of processing the event, the view's bounds may need to be changed, the view would call requestLayout() .

2. Similarly, if in the course of processing the event the view's appearance may need to be changed, the view invalidate() would call .

3. If either requestLayout() or invalidate() were called, the framework would take care of measuring, laying out, and drawing the tree as Appro Priate.

Two. Instance

     Public void setswitchtypeface (Typeface tf) {        if (mtextpaint.gettypeface () = tf) {            Mtextpaint.settypeface (TF);            Requestlayout ();            Invalidate ();        }    }      Public void setswitchpadding (int  pixels) {        = pixels;        Requestlayout ();    }