java - why the coordinates of a view is always Zero -

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i created simple example know how can coordinates of given view. below attempts, , display 0.0. idea why happens?

code:

private int [] tv1location = new int[2]; private int [] tv2location = new int[2];  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.main);      rect tv1rect = new rect();     rect tv2rect = new rect();      tablelayout tl = (tablelayout) findviewbyid(r.id.tablelayout);     textview tv1 = (textview) findviewbyid(r.id.tv1);     textview tv2 = (textview) findviewbyid(r.id.tv2);      tv1.getlocalvisiblerect(tv1rect);     tv1.getlocationonscreen(tv1location);      tv2.getlocalvisiblerect(tv1rect);     tv2.getlocationonscreen(tv2location);       tv1.settext("xcords: "+tv1.getx()+", ycords: "+tv1.gety());     tv2.settext("xcords: "+tv2.getx()+", ycords: "+tv2.gety());     //tv2.settext("xcords: "+tv2location[0]+", ycords: "+tv2location[1]);     //tv1.settext("xcords: "+tv1location[0]+", ycords: "+tv1location[1]);     //tv2.settext("xcords: "+tv2location[0]+", ycords: "+tv2location[1]);

updated

@override public void onwindowfocuschanged(boolean hasfocus) {     // todo auto-generated method stub     super.onwindowfocuschanged(hasfocus);      if (hasfocus) {             tv1.getlocalvisiblerect(tv1rect);             tv1.getlocationonscreen(tv1location);              tv2.getlocalvisiblerect(tv1rect);             tv2.getlocationonscreen(tv2location);              //tv1.settext("xcords: "+tv1.getx()+", ycords: "+tv1.gety());             //tv2.settext("xcords: "+tv2.getx()+", ycords: "+tv2.gety());             //tv1.settext("xcords: "+tv1rect.centerx()+", ycords: "+tv1rect.centery());             //tv2.settext("xcords: "+tv2rect.centerx()+", ycords: "+tv2rect.centery());             //tv1.settext("xcords: "+tv1location[0]+", ycords: "+tv1location[1]);             //tv2.settext("xcords: "+tv2location[0]+", ycords: "+tv2location[1]);         }     }

you views not visible yet. shouldn't put code check things in oncreate() because might not drawn yet. there several different ways accomplish this. best place may in onwindowfocuschanged

the docs onwindowfocuschanged()

this best indicator of whether activity visible user

so know views laid out @ point. post runnable on views or use.

here answer uses listener ongloballayout work need.


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