how to appear a modeless dialog by draging the button on the main dialog?

In a dialog based app program, when the program starts, there are two dialogs: MainDlg and ModeLessDlg, and if you press the "close "Button on the ModelessDlg, the "DragMe" button will appear on the MainDlg, and if you click and drag the "DragMe" button on the MainDlg, the ModeLessDlg will appear in the place.

how to realize the function? I can not ahieve the function that is"if you click and drag the "DragMe" button on the MainDlg, the ModeLessDlg will appear in the place"

can you help me? thank you!

do you want to let modelessdlg in maindlg ?
take all maindlg client place?

The only thing you should learn is how to use these 2 WINAPI functions.
ShowWindow(BOOL)
GetDlgItem(UINT)

look them up in MSDN..

no, I want the modeless dialog independent, I click and drag the button on the Maindlg ,the modeless dialog can appear there

reply wuyh :

I tried it , but It can not get the result