Hello,

AddStyle() would not be used if you customize all your style with CSS. WebToolBar/WebMenuBar provides properties which can be configured for its style. I already sent you the sample which I include all the style  in CSS and set it in those properties.

 <MenuStyleSettings BackgroundStripColor2="" MenuDropShadow="True" MenuAnimation="True"
  MenuWindowType="Normal" BackgroundStripColor="#E3EFFF">
 <CustomStyle CssClass="CustomStyle">
 </CustomStyle>
 <DisabledItemStyle>
 <Over CssClass="DisabledItemStyle-Over">
 </Over>
 <Normal CssClass="DisabledItemStyle-Normal">
 </Normal>
 </DisabledItemStyle>
 <CheckedItemStyle>
 <Over CssClass="CheckedItemStyle-Over">
 </Over>
 <Normal CssClass="CheckedItemStyle-Normal">
 </Normal>
 </CheckedItemStyle>
 <SeparatorStyle CssClass="SeparatorStyle"></SeparatorStyle>
 <FrameStyle CssClass="FrameStyle">
 </FrameStyle>
 <ItemStyle>
 <Over CssClass="ItemStyle-Over">
 </Over>
 <Normal CssClass="ItemStyle-Normal">
 </Normal>
 </ItemStyle>
 </MenuStyleSettings>
 <HeaderButtonStyle>
 <Active CssClass="HeaderButtonStyle-Active">
 </Active>
 <Over CssClass="HeaderButtonStyle-Over">
 </Over>
 <Normal CssClass="HeaderButtonStyle-Normal">
 </Normal>
 </HeaderButtonStyle>
 <BodyStyle BackColor="#BFDBFF"></BodyStyle>
 <CommandStyle>
 <Active CssClass="CommandStyle-Active">
 </Active>
 <Over CssClass="CommandStyle-Over">
 </Over>
 <Normal CssClass="CommandStyle-Normal">
 </Normal>
 </CommandStyle>
 <CommandDisabledStyle CssClass="CommandDisabledStyle">
 </CommandDisabledStyle>
 <SeparatorStyle CssClass="SeparatorStyle1"></SeparatorStyle>
 <HandleStyle BackColor="#BFDBFF"></HandleStyle>
 <OptionStyle BackColor="#C4C4AD"></OptionStyle>
 <HeaderCaptionStyle CssClass="HeaderCaptionStyle">
 </HeaderCaptionStyle>

I will need to discuss with our developer about AutoFitColumn property. But after configure CSS, without AutoFitColumn, the performance works well.

Regards,
Handy

Hi,

Yes. All the style should be customized in CSS. If you don't use CSS, WebToolBar/WebMenuBar would use AddStyle() (default mechanism). As I said before, somehow this method is not functioning in IE.
If you run the sample in other browser, the performance would not slow.
Also, In your sample, I didn't touch anything about AutoFitColumn. 

Regards,
Handy

Hello Maged,

I am sorry that I was not being detail in my previous post. You can change the DataKeyField with ItemID, but you also need to add ItemID in your column. This the one that caused the error.
If you don't like to show ItemID column, you can set Visible false properties in that column.
When you specify a datakeyfield, It must be need also added into your column. Otherwise, you will face the error.

Regards,
Handy

Hello Jean,

I got a response from our developer teams. This issue happens only when you resize the window.
 Our WebTextEditor has its own logic mechanism to resize the toolbar. When the size is getting reduced, some of command would be hidded into "more options"dropdown button. Or, it will moved into the bottom.
In other words, your scenario messed up with our resize and hide scenario.
Is it possible for not using hide?
Such as switch the current image with your custom image. You can also override the command.
Or you can use disable command instead of hiding the command.

Regards,
Handy  

Hello Maged,

Based on Martin sample, there is no field "ItemID" in his database. Also, DataKeyField is necessary to be filled. Otherwise, you will find some issue in insert, update and delete. Please fill DataKeyField properties with your current Primary key in database.

Regards,
Handy