Straight to the question. There isn't a property which restricts the tooltip loading. The tooltip control is loaded as soon as the data is retrieved. After Setting Width
properties of the RadToolTip, the loading panel will be shown which indicates that the data is loading.
In our online demo the loading of the RadToolTip takes around 300 milliseconds. Could you please profile how long it takes to retrieve the data from your SQL server ? E.g.
var start = DateTime.Now;
// Example: Thread.Sleep(5000);
// execute here your logic for retrieving the data
var end = DateTime.Now;
var loadingTime = end - start;
Keep in mind that when RadToolTip is used with an Ajax request the whole page life cycle is executed.
In case you still experience the mentioned issue, please setup a working sample project, that reproduces the problematic behavior, and send it for a local test.
the Telerik team
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