Migrated controls_windows.go to C.

1 files changed, 71 insertions, 0 deletions

diff --git a/redo/controls_windows.c b/redo/controls_windows.c
new file mode 100644
index 0000000..dadce75
--- /dev/null
+++ b/redo/controls_windows.c
@@ -0,0 +1,71 @@
+/* 17 july 2014 */
+
+#include "winapi_windows.h"
+
+HWND newWidget(LPCWSTR class, DWORD style, DWORD extstyle)
+{
+	HWND hwnd;
+
+	hwnd = CreateWindowExW(
+		extstyle,
+		class, L"",
+		style | WS_CHILD | WS_VISIBLE,
+		CW_USEDEFAULT, CW_USEDEFAULT,
+		CW_USEDEFAULT, CW_USEDEFAULT,
+		/*
+		the following has the consequence of making the control message-only at first
+		this shouldn't cause any problems... hopefully not
+		but see the msgwndproc() for caveat info
+		also don't use low control IDs as they will conflict with dialog boxes (IDCANCEL, etc.)
+		*/
+		msgwin, (HMENU) 100, hInstance, NULL);
+	if (hwnd == NULL) {
+		xpanic("error creating control", GetLastError());
+	return hwnd;
+}
+
+void controlSetParent(HWND control, HWND parent)
+{
+	if (SetParent(control, parent) == NULL)
+		xpanic("error changing control parent", GetLastError());
+}
+
+/*
+all controls that have events receive the events themselves through subclasses
+to do this, all windows (including the message-only window; see http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q104069) forward WM_COMMAND to each control with this function
+*/
+LRESULT forwardCommand(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+	HWND control = (HWND) lParam;
+
+	/* don't generate an event if the control (if there is one) is unparented (a child of the message-only window) */
+	if (control != NULL && IsChild(msgwin, control) == 0)
+		return SendMessageW(control, msgCOMMAND, wParam, lParam);
+	return DefWindowProcW(hwnd, uMsg, wParam, lParam);
+}
+
+static LRESULT CALLBACK buttonSubProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR id, DWORD_PTR data)
+{
+	switch (uMsg) {
+	case msgCOMMAND:
+		if (HIWORD(wParam) == BN_CLICKED) {
+			buttonClicked(data);
+			return 0;
+		}
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	case WM_NCDESTROY:
+		if ((*fv_RemoveWindowSubclass)(hwnd, buttonSubProc, id) == FALSE)
+			xpanic("error removing Button subclass (which was for its own event handler)", GetLastError());
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	default:
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	}
+	xmissedmsg("Button", "buttonSubProc()", uMsg);
+	return 0;		/* unreached */
+}
+
+void setButtonSubclass(HWND hwnd, void *data)
+{
+	if ((*fv_SetWindowSubclass)(hwnd, buttonSubProc, 0, (DWORD_PTR) data) == FALSE)
+		xpanic("error subclassing Button to give it its own event handler", GetLastError());
+}