When a user double-clicks a dbgrid, I show a non-modal form.
When they close that form, I want to refresh the grid.
To accomplish that, I have tried the following:
1 - Define a custom message constant:
const
WM_REFRESH_MSG = WM_USER + 1; //defined in a globally available unit
2 - In the OnClose event of my non-modal form, I have this:
procedure TMyNonModalForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
PostMessage(Self.Handle,WM_REFRESH_MSG,0,0);
end;
3 - In the private declarations of the form that holds the dbGrid, I have this:
procedure OnRefreshRequest(var Msg: TMessage); message WM_REFRESH_MSG;
...
procedure TMyFormWithADBGrid.OnRefreshRequest(var Msg: TMessage);
begin
RefreshGrid;
end;
After doing these things, the PostMessage fires fine, but the OnRefreshRequest procedure never runs. What am I doing wrong?
Aside from the message name in the other answer, you are posting a message to Self.Handle while Self is going away. You probably meant to post to a different handle (the window that launched the modeless one). Give your modeless window access to that handle when you create it, and post the message there instead.