WinBinder Manual/WinBinder objects
From wiki.swiftlytilting.com
Windows uses handles of type HWND to refer to most GUI objects. Since handles are 32-bit pointers that are unique to each window, it would be tempting to use them as PHP variables to refer to controls. However, this approach is not ideal for the following reasons:
- Some controls, like toolbar buttons, are not actually windows and therefore do not have a real handle;
- It is often necessary to store additional information about a control.
Therefore the WinBinder Object (WBOBJ) structure is defined. All WinBinder windows and controls are of type WBOBJ. The structure contains the window handle (HWND) and more. Below is a copy of the WBOBJ definition in WB.H:
// WinBinder object (window, control, or menu), stored with SetWindowLong() / GWL_USERDATA
typedef struct _wbo {
HWND hwnd; // Control or window handle
UINT id; // Control identifier
UINT uClass; // Object class
int item; // Item index
int subitem; // Subitem index
DWORD style; // WinBinder style
struct _wbo *parent; // Parent window
LPTSTR pszCallBackFn; // Callback function
LPARAM lparam; // User-defined parameter
union {
LONG lparams[8]; // General-purpose parameter array
struct {
RECT rcTitle; // Title area
AREA arMin; // Minimum window area
AREA arMax; // Maximum window area
};
};
HBITMAP pbuffer; // Screen buffer for windows
} WBOBJ, *PWBOBJ;
The WinBinder functions wb_create_control() and wb_create_window() effectively return a pointer to the window's WBOBJ structure as a long integer. This pointer is also stored (with Window API function SetWindowLong() and GWL_USERDATA) in every window. Therefore it always possible to obtain the HWND from a WBOBJ and vice-versa, for any given window or control.
The first LPARAM type field, lparam, carries the value of the param argument that is passed in functions wb_create_control() and wb_create_window(). The array of LPARAMs, lparams, is reserved for internal use and can be used to carry additional user information or additional 32-bit pointers. The latter are accessible only via the wb_peek() function.
Example: obtaining a window handle
// Declare constants for the WBOBJ structure
define("WBOBJ", "Vhwnd/Vid/Vuclass/litem/lsubitem/Vstyle/Vparent/Vhandler/Vlparam/V8lparams/Vpbuffer");
define("WBOBJ_RAW", "V3l2V13");
define("WBOBJ_SIZE", 72);
$wbobj = unpack(WBOBJ, wb_peek($window, WBOBJ_SIZE));
$hwnd = $wbobj["hwnd"];
echo "The handle for this window is $hwnd.";
