I'm using a RadTabStrip that contains RadTabs with Silverlight grids (RadGridView). The grids are configured with validators. On postback while attempting to save to the database I'm having the following issue: Can't move focus to the control because it is invisible, not enabled, or of a type that does not accept the focus. The Java script debugger breaks on the d.focus() call in the script segment below. This segement is from RadInputControl.js from Telerik.Web.UI. d is the Silverlight grid and its offsetWidth is 0 at this point. Also, this grid is not on the current visible tab. Let me know if you need more information.

Thanks, Mike Fernandez

if(typeof(ValidatorSetFocus)=="function"){

ValidatorSetFocus=function(f,c){

var d;

if(typeof(f.controlhookup)=="string"){

var a;

if((typeof(c)!="undefined")&&(c!=null)){

if((typeof(c.srcElement)!="undefined")&&(c.srcElement!=null)){

a=c.srcElement;

}

else{

a=c.target;

}

}

if((typeof(a)!="undefined")&&(a!=null)&&(typeof(a.id)=="string")&&(a.id==f.controlhookup)){

d=a;

}

}

if((typeof(d)=="undefined")||(d==null)){

d=document.getElementById(f.controltovalidate);

}

var b=false;

if((d.style)&&(typeof(d.style.visibility)!="undefined")&&(d.style.visibility=="hidden")&&

(typeof(d.style.width)!="undefined")&&(document.getElementById(d.id+"_text")||

document.getElementById(d.id+"_dateInput_text"))&&(d.tagName.toLowerCase()=="input"||

d.tagName.toLowerCase()=="textarea")){

b=true;

}

if((typeof(d)!="undefined")&&(d!=null)&&(d.tagName.toLowerCase()!="table"||(typeof(c)=="undefined")

||(c==null))&&((d.tagName.toLowerCase()!="input")||(d.type.toLowerCase()!="hidden"))&&

(typeof(d.disabled)=="undefined"||d.disabled==null||d.disabled==false)&&(typeof(d.visible)=="undefined"||

d.visible==null||d.visible!=false)&&(IsInVisibleContainer(d)||b)){

if(d.tagName.toLowerCase()=="table"&&(typeof(__nonMSDOMBrowser)=="undefined"||__nonMSDOMBrowser)){

var g=d.getElementsByTagName("input");

var e=g[g.length-1];

if(e!=null){

d=e;

}

}

if(typeof(d.focus)!="undefined"&&d.focus!=null){

if(b&&document.getElementById(d.id+"_text")){

document.getElementById(d.id+"_text").focus();

}

else {

if(b&&document.getElementById(d.id+"_dateInput_text")){

document.getElementById(d.id+"_dateInput_text").focus();

}

else{

d.focus();  //breaks here.

}

}

Page_InvalidControlToBeFocused=d;

}

}

};

}

This turned out to be a problem with one of our custom validators and not an issue with the RadTabStrip.