Sumatra checkbox in tree view (made with https://codeeval.dev)

sumatra checkbox tree.txt

https://docs.microsoft.com/en-us/windows/win32/controls/tree-view-control-reference
https://docs.microsoft.com/en-us/windows/win32/controls/tree-view-controls#tree-view-image-lists
https://docs.microsoft.com/en-us/windows/win32/controls/tree-view-controls#tree-view-styles
https://docs.microsoft.com/en-us/windows/win32/controls/tree-view-control-window-styles

typedef struct tagTVITEMCHANGE {
  NMHDR     hdr;
  UINT      uChanged;
  HTREEITEM hItem;
  UINT      uStateNew;
  UINT      uStateOld;
  LPARAM    lParam;
} NMTVITEMCHANGE;

typedef struct _nmhdr {
  HWND hwndFrom;
  UINT idFrom;
  UINT code;
} NMHDR;

typedef struct tagNMTREEVIEWA {
  NMHDR   hdr;
  UINT    action;
  TVITEMA itemOld;
  TVITEMA itemNew;
  POINT   ptDrag;
} NMTREEVIEWA, *LPNMTREEVIEWA;

https://docs.microsoft.com/en-us/windows/win32/api/commctrl/ns-commctrl-tvitemw
typedef struct tagTVITEMA {
  UINT      mask;
  HTREEITEM hItem;
  UINT      state;
  UINT      stateMask;
  LPSTR     pszText;
  int       cchTextMax;
  int       iImage;
  int       iSelectedImage;
  int       cChildren;
  LPARAM    lParam;
} TVITEMA, *LPTVITEMA;

TVS_CHECKBOXES
State image 1 is the unchecked box and state image 2 is the checked box. Setting the state image to zero removes the check box altogether.

https://docs.microsoft.com/en-us/windows/win32/api/Commctrl/ns-commctrl-tvitemexa
Vista+
typedef struct tagTVITEMEXA {
  UINT      mask;
  HTREEITEM hItem;
  UINT      state;
  UINT      stateMask;
  LPSTR     pszText;
  int       cchTextMax;
  int       iImage;
  int       iSelectedImage;
  int       cChildren;
  LPARAM    lParam;
  int       iIntegral;
  UINT      uStateEx;
  HWND      hwnd;
  int       iExpandedImage;
  int       iReserved;
} TVITEMEXA, *LPTVITEMEXA;