The TTN_NEEDTEXT notification message retrieves text for a tool. This notification message is sent in the form of a WM_NOTIFY message.
TTN_NEEDTEXT
idTT = (int) wParam;
lpttt = (LPTOOLTIPTEXT) lParam;
Parameters
idTT
Identifier of the tooltip control.
lpttt
Pointer to a TOOLTIPTEXT structure. The hdr member identifies the tool for which text is needed. The receiving window can specify the string by taking one of the following actions:
·Copying the text to the buffer specified by the szText member.
·Copying the address of the buffer that contains the text to the lpszText member.
·Copying the identifier of a string resource to the lpszText member and copying the handle of the instance that contains the resource to the hinst member.
Return Values
No return value.
Remarks
This notification message is sent to the window specified in the hwnd member of the TOOLINFO structure for the tool. This notification is sent only if the LPSTR_TEXTCALLBACK value is specified when the tool is added to a tooltip control.
When a TTN_NEEDTEXT notification is received, the application can set or clear the TTF_RTLREADING value in the uFlags member of the TOOLTIPTEXT structure pointed to by lpttt as required. This is the only flag that can be changed during the notification callback.
See Also