To show the WaitingPopup while loading dynamic content to the dialog control using AJAX request, after the data is retrieved from client the WaitingPopup should be closed.
Please refer the following code snippet.
In the above sample, when we open the dialog the AJAX request will be sent to the corresponding page to load the content of dialog component. Before the AJAX request is initiated, the WaitingPopup is shown using the beforeSend event of AJAX. In the success function of AJAX, the WaitingPopup is closed and the obtained data will be placed to the content of dialog component.
You can download the complete sample from the following location.
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