Creating Modeless Dialog Boxes
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The latest version of this topic can be found at Creating Modeless Dialog Boxes.
For a modeless dialog box, you must provide your own public constructor in your dialog class. To create a modeless dialog box, call your public constructor and then call the dialog object's Create member function to load the dialog resource. You can call Create either during or after the constructor call. If the dialog resource has the property WS_VISIBLE, the dialog box appears immediately. If not, you must call its ShowWindow member function.