1 files changed, 62 insertions, 0 deletions
diff --git a/prev/control_windows.c b/prev/control_windows.c
new file mode 100644
index 0000000..03af5c6
--- /dev/null
+++ b/prev/control_windows.c
@@ -0,0 +1,62 @@
+// 17 july 2014
+
+#include "winapi_windows.h"
+#include "_cgo_export.h"
+
+HWND newControl(LPWSTR 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());
+}
+
+void controlSetControlFont(HWND which)
+{
+	SendMessageW(which, WM_SETFONT, (WPARAM) controlFont, TRUE);
+}
+
+void moveWindow(HWND hwnd, int x, int y, int width, int height)
+{
+	if (MoveWindow(hwnd, x, y, width, height, TRUE) == 0)
+		xpanic("error setting window/control rect", GetLastError());
+}
+
+LONG controlTextLength(HWND hwnd, LPWSTR text)
+{
+	HDC dc;
+	HFONT prev;
+	SIZE size;
+
+	dc = GetDC(hwnd);
+	if (dc == NULL)
+		xpanic("error getting DC of control for text length", GetLastError());
+	prev = SelectObject(dc, controlFont);
+	if (prev == NULL)
+		xpanic("error setting control font to DC for text length", GetLastError());
+	if (GetTextExtentPoint32W(dc, text, wcslen(text), &size) == 0)
+		xpanic("error actually getting text length", GetLastError());
+	if (SelectObject(dc, prev) != controlFont)
+		xpanic("error restoring previous control font to DC for text length", GetLastError());
+	if (ReleaseDC(hwnd, dc) == 0)
+		xpanic("error releasing DC of control for text length", GetLastError());
+	return size.cx;
+}