Up-Down control doesn't show its position in its buddy window - c++

Question

I created an up-down control by the following code.
HWND hEdit, hUpDown;
hEdit = CreateWindowExW(WS_EX_CLIENTEDGE,
L"EDIT",
Content.c_str(),
ES_LEFT | WS_VISIBLE | WS_CHILD,
600,
260,
100,
25,
hWndParent,
NULL,
hInstance,
NULL);
INITCOMMONCONTROLSEX iccx;
iccx.dwSize = sizeof(INITCOMMONCONTROLSEX);
iccx.dwICC = ICC_UPDOWN_CLASS;
InitCommonControlsEx(&iccx);
hUpDown = CreateWindowExW( 0,
UPDOWN_CLASSW,
L"",
UDS_ARROWKEYS | UDS_ALIGNRIGHT | WS_VISIBLE | WS_CHILD,
0,
0,
0,
0,
hWndParent,
NULL,
hInstance,
NULL);
SendMessageW(hUpDown, UDM_SETBUDDY, (WPARAM) hEdit, (LPARAM) NULL);
SendMessageW(hUpDown, UDM_SETRANGE32, (WPARAM) 0, (LPARAM) 100);
Sleep(5000);
SendMessageW(hUpDown, UDM_SETPOS32, (WPARAM) NULL, (LPARAM) 20);
Sleep(5000);
SendMessageW(hUpDown, UDM_SETPOS32, (WPARAM) NULL, (LPARAM) 60);
I checked the return values of the SendMessageW() functions. They terminate successfully by returning the previous position value as documented.
The created up-down control looks normal:
The problem is, sending the UDM_SETPOS32 message, clicking the up and down arrows and pressing the up and down keys on the keyboard have no effect. I can't change the contents of the edit control (the buddy window of the up-down control) without directly typing something into it. It just stays empty.
I am able to type anything in it manually by using keyboard:
How do I change the position/value of this up-down control by pressing keyboard arrow keys, by clicking the arrows in the GUI and by sending UDM_SETPOS32 in the code? What am I missing in my code?

Answer 1

Use the style UDS_SETBUDDYINT to the up-down control while creating it.
From MSDN documentation:
UDS_SETBUDDYINT
Causes the up-down control to set the text of the buddy window (using the WM_SETTEXT message) when the position changes. The text consists of the position formatted as a decimal or hexadecimal string.
Change the creation code of the up-down control like this by adding the UDS_SETBUDDYINT style:
hUpDown = CreateWindowExW( 0,
UPDOWN_CLASSW,
L"",
UDS_SETBUDDYINT | UDS_ARROWKEYS | UDS_ALIGNRIGHT | WS_VISIBLE | WS_CHILD,
0,
0,
0,
0,
hWndParent,
NULL,
hInstance,
NULL);