XRC and wxPython

[Austin]

I've seen the examples about xrc and wxpython. Most examples demostrate one
frame or dialog and use menubar or button to produce events. I met a
problem.
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sample.xrc
<?xml version="1.0" ?>
<resource>
<object class="wxFrame" name="MainFrame">
<title>Simple Test</title>
<object class="wxButton" name="Button1">
<label>hi</label>
</object>
</object>
</resource>

close.xrc
<?xml version="1.0" ?>
<resource>
<object class="wxDialog" name="DIALOG1">
<title>close</title>
<object class="wxButton" name="CloseButton">
<label>close</label>
</object>
</object>
</resource>

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sample is a frame, and close is a dialog. Assume that ex.(sample.py) is a
main program. When you click Button1, it will show the dialog ex.(close.py).
And you click close button in close.py, it will close but the main frame
still exists. Because most examples don't show how to open another dialog, i
try to write codes referenced by the examples but it's doesn't work. Could
anybody show me the examples used those two xrc files or some other useful
websites? Thanks a lot.