The RadDateInput always has worked this way, even before the 2012 Q1. We have unified the behaviour of all input controls, and currently they all have several stages client side, to be more customizable.
Actually in sample page, you don't have to do nothing in order to make your TextBoxes to work properly. Because clicking on regular Button blurs the TextBox either way, causing it's value to be set properly.
See, there was issues before, that we managed to fix, by changing the behaviour. An example of them is that before if the TextBox has AutoPostBack="true" pressing enter key, will cause 2 postbacks, one of them that to be aborted (one from the TextBox, and one from the DefaultButton). Actually you can check why we did this, since they are lots of additional benefits:
What makes different the RadInputControl from regular Asp:TextBox is that the RadInputControl has several different stages:
Focused - the user edits value (the value is not considered as edited, until the user perform action like blur, or pressing enter). It is the same as if you are editing a filename in your windows explorer. If you are currently typing, and some another action disturbs your typing (like timer making autoPostBack), the edit will be canceled, not applied. It makes most sens for the users and gives them better control.
Blurred - the user has finished with editing, now he could see his formatted value, or Empty or Error messages if they are such.
Focused after pressing enter with no AutoPostBack - The value will be applied internally, and reformatted if required, but the focus is still inside the input.
Pressing enter key with AutoPostBack - The value will be formatted and the control will initiate PostBack.
This is making the RadTextBox hardly for using with timers, but not unusable, you could still force it to apply new value in the code of your timer using the set_value() and get_textBoxValue functions. For us it is bad idea to consider the value that your user is currently typing as "final", the users are making mistakes, and they should be able to edit the values before deciding that they should submit the form.
the Telerik team
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