Began implementing Area.OpenTextFieldAt() on Windows.

redo/area_windows.c

@@ -438,3 +438,37 @@ HWND newArea(void *data)
 		xpanic("container creation failed", GetLastError());
 	return hwnd;
 }
+
+static LRESULT CALLBACK areaTextFieldSubProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR id, DWORD_PTR data)
+{
+	switch (uMsg) {
+	case WM_KILLFOCUS:
+		ShowWindow(hwnd, SW_HIDE);
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	case WM_NCDESTROY:
+		if ((*fv_RemoveWindowSubclass)(hwnd, areaTextFieldSubProc, id) == FALSE)
+			xpanic("error removing Area TextField subclass (which was for handling WM_KILLFOCUS)", GetLastError());
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	default:
+		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
+	}
+	xmissedmsg("Area TextField", "areaTextFieldSubProc()", uMsg);
+	return 0;		// unreached
+}
+
+HWND newAreaTextField(HWND area)
+{
+	HWND tf;
+
+	tf = CreateWindowExW(textfieldExtStyle | WS_EX_TOOLWINDOW,
+		L"edit", L"",
+		textfieldStyle | WS_POPUP,
+		0, 0, 0, 0,
+		area,			// owner window
+		NULL, hInstance, NULL);
+	if (tf == NULL)
+		xpanic("error making Area TextField", GetLastError());
+	if ((*fv_SetWindowSubclass)(tf, areaTextFieldSubProc, 0, (DWORD_PTR) NULL) == FALSE)
+		xpanic("error subclassing Area TextField to give it its own WM_KILLFOCUS handler", GetLastError());
+	return tf;
+}

redo/area_windows.go

@@ -18,6 +18,8 @@ type area struct {
 	_hwnd		C.HWND
 
 	clickCounter	*clickCounter
+
+	textfield		C.HWND
 }
 
 func makeAreaWindowClass() error {
@@ -37,6 +39,8 @@ func newArea(ab *areabase) Area {
 	}
 	a._hwnd = C.newArea(unsafe.Pointer(a))
 	a.SetSize(a.width, a.height)
+	a.textfield = C.newAreaTextField(a._hwnd)
+	C.controlSetControlFont(a.textfield)
 	return a
 }
 
@@ -67,6 +71,31 @@ func (a *area) RepaintAll() {
 	C.SendMessageW(a._hwnd, C.msgAreaRepaintAll, 0, 0)
 }
 
+// TODO somehow use textfield.preferredSIze() here
+func (a *area) OpenTextFieldAt(x, y int) {
+	if x < 0 || x >= a.width || y < 0 || y >= a.height {
+		panic(fmt.Errorf("point (%d,%d) outside Area in Area.OpenTextFieldAt()", x, y))
+	}
+	C.moveWindow(a.textfield, C.int(x), C.int(y), C.int(200), C.int(20))
+	C.ShowWindow(a.textfield, C.SW_SHOW)
+	// TODO SetFocus
+}
+
+func (a *area) TextFieldText() string {
+	return getWindowText(a.textfield)
+}
+
+func (a *area) SetTextFieldText(text string) {
+	t := toUTF16(text)
+	C.setWindowText(a.textfield, t)
+	// TODO
+//	c.settextlen(C.controlTextLength(hwnd, t))
+}
+
+func (a *area) OnTextFieldDismissed(f func()) {
+	// TODO
+}
+
 //export doPaint
 func doPaint(xrect *C.RECT, hscroll C.int, vscroll C.int, data unsafe.Pointer, dx *C.intptr_t, dy *C.intptr_t) unsafe.Pointer {
 	a := (*area)(data)

redo/textfield_windows.go

@@ -19,8 +19,8 @@ var editclass = toUTF16("EDIT")
 
 func startNewTextField(style C.DWORD) *textfield {
 	hwnd := C.newControl(editclass,
-		style | C.ES_AUTOHSCROLL | C.ES_LEFT | C.ES_NOHIDESEL | C.WS_TABSTOP,
+		style | C.textfieldStyle,
-		C.WS_EX_CLIENTEDGE)		// WS_EX_CLIENTEDGE without WS_BORDER will show the canonical visual styles border (thanks to MindChild in irc.efnet.net/#winprog)
+		C.textfieldExtStyle)		// WS_EX_CLIENTEDGE without WS_BORDER will show the canonical visual styles border (thanks to MindChild in irc.efnet.net/#winprog)
 	t := &textfield{
 		_hwnd:		hwnd,
 		changed:		newEvent(),

redo/winapi_windows.h

@@ -67,6 +67,8 @@ extern void setButtonSubclass(HWND, void *);
 extern void setCheckboxSubclass(HWND, void *);
 extern BOOL checkboxChecked(HWND);
 extern void checkboxSetChecked(HWND, BOOL);
+#define textfieldStyle (ES_AUTOHSCROLL | ES_LEFT | ES_NOHIDESEL | WS_TABSTOP)
+#define textfieldExtStyle (WS_EX_CLIENTEDGE)
 extern void setTextFieldSubclass(HWND, void *);
 extern void textfieldSetAndShowInvalidBalloonTip(HWND, WCHAR *);
 extern void textfieldHideInvalidBalloonTip(HWND);
@@ -127,6 +129,7 @@ extern void calculateBaseUnits(HWND, int *, int *, LONG *);
 extern void repaintArea(HWND, RECT *);
 extern DWORD makeAreaWindowClass(char **);
 extern HWND newArea(void *);
+extern HWND newAreaTextField(HWND);
 
 // imagelist_windows.c
 extern HBITMAP unscaledBitmap(void *, intptr_t, intptr_t);