Double-click on the title bar. What happened?

我的马甲

FormDblClick does not work.

xietao405

No event will trigger it ...

夜云男爵

Double clicking on the title bar will trigger the WM_NCLBUTTONDBLCLK message. Intercepting this message is fine.

我的马甲

Thank you upstairs, can you elaborate more? It is better to give a small piece of code.

夜云男爵

I guess the next step is to ask how to intercept this message and answer it in advance.

In the unit file .h:
private: // User declarations
    void __fastcall WndProc (TMessage&Msg);

In the unit file .cpp:
void __fastcall TForm1 :: WndProc (TMessage&Msg)
{
    if (Msg.Msg == WM_NCLBUTTONDBLCLK)
    {
        ShowMessage ("It looks like I double-clicked the title bar");
        // If you don't want the title bar to respond to this double-click message, add the following sentence
        // return;
    }
    TForm :: WndProc (Msg);
}