Implemented more/most of Area.OpenTextFieldAt() on Windows.

redo/area_windows.c

@@ -233,6 +233,26 @@ static void scrollArea(HWND hwnd, void *data, WPARAM wParam, int which)
 		dx = 0;
 		dy = delta;
 	}
+
+	// first move the edit control, if any, to avoid artifacting
+	if ((HWND) GetWindowLongPtrW(hwnd, 0) != NULL) {
+		HWND edit;
+		int x, y;
+
+		edit = (HWND) GetWindowLongPtrW(hwnd, 0);
+		x = (int) GetWindowLongPtrW(hwnd, sizeof (LONG_PTR));
+		y = (int) GetWindowLongPtrW(hwnd, 2 * sizeof (LONG_PTR));
+		x += dx;
+		y += dy;
+		if (SetWindowPos(edit, NULL, x, y, 0, 0, SWP_NOSIZE | SWP_NOZORDER) == 0)
+			xpanic("error moving Area TextField in response to scroll", GetLastError());
+		SetWindowLongPtrW(hwnd, sizeof (LONG_PTR), (LONG_PTR) x);
+		SetWindowLongPtrW(hwnd, 2 * sizeof (LONG_PTR), (LONG_PTR) y);
+		// TODO doesn't work?
+		if (InvalidateRect(edit, NULL, TRUE) == 0)
+			xpanic("error marking Area TextField as needing redraw", GetLastError());
+	}
+
 	if (ScrollWindowEx(hwnd,
 		(int) dx, (int) dy,
 		// these four change what is scrolled and record info about the scroll; we're scrolling the whole client area and don't care about the returned information here
@@ -253,6 +273,9 @@ static void scrollArea(HWND hwnd, void *data, WPARAM wParam, int which)
 	// NOW redraw it
 	if (UpdateWindow(hwnd) == 0)
 		xpanic("error updating Area after scrolling", GetLastError());
+	if ((HWND) GetWindowLongPtrW(hwnd, 0) != NULL)
+		if (UpdateWindow((HWND) GetWindowLongPtrW(hwnd, 0)) == 0)
+			xpanic("error updating Area TextField after scrolling", GetLastError());
 }
 
 static void adjustAreaScrollbars(HWND hwnd, void *data)
@@ -411,7 +434,8 @@ DWORD makeAreaWindowClass(char **errmsg)
 	wc.hInstance = hInstance;
 	wc.hIcon = hDefaultIcon;
 	wc.hCursor = hArrowCursor,
-	wc.hbrBackground = NULL;		// no brush; we handle WM_ERASEBKGND
+	wc.hbrBackground = NULL;				// no brush; we handle WM_ERASEBKGND
+	wc.cbWndExtra = 3 * sizeof (LONG_PTR);		// text field handle, text field current x, text field current y
 	if (RegisterClassW(&wc) == 0) {
 		*errmsg = "error registering Area window class";
 		return GetLastError();
@@ -440,6 +464,7 @@ static LRESULT CALLBACK areaTextFieldSubProc(HWND hwnd, UINT uMsg, WPARAM wParam
 	switch (uMsg) {
 	case WM_KILLFOCUS:
 		ShowWindow(hwnd, SW_HIDE);
+		areaTextFieldDone((void *) data);
 		return (*fv_DefSubclassProc)(hwnd, uMsg, wParam, lParam);
 	case WM_NCDESTROY:
 		if ((*fv_RemoveWindowSubclass)(hwnd, areaTextFieldSubProc, id) == FALSE)
@@ -452,7 +477,7 @@ static LRESULT CALLBACK areaTextFieldSubProc(HWND hwnd, UINT uMsg, WPARAM wParam
 	return 0;		// unreached
 }
 
-HWND newAreaTextField(HWND area)
+HWND newAreaTextField(HWND area, void *goarea)
 {
 	HWND tf;
 
@@ -460,11 +485,34 @@ HWND newAreaTextField(HWND area)
 		L"edit", L"",
 		textfieldStyle | WS_CHILD,
 		0, 0, 0, 0,
-		area,			// owner window
-		NULL, hInstance, NULL);
+		area, NULL, hInstance, NULL);
 	if (tf == NULL)
 		xpanic("error making Area TextField", GetLastError());
-	if ((*fv_SetWindowSubclass)(tf, areaTextFieldSubProc, 0, (DWORD_PTR) NULL) == FALSE)
+	if ((*fv_SetWindowSubclass)(tf, areaTextFieldSubProc, 0, (DWORD_PTR) goarea) == FALSE)
 		xpanic("error subclassing Area TextField to give it its own WM_KILLFOCUS handler", GetLastError());
 	return tf;
 }
+
+void areaOpenTextField(HWND area, HWND textfield, int x, int y, int width, int height)
+{
+	int sx, sy;
+	int baseX, baseY;
+	LONG unused;
+
+	getScrollPos(area, &sx, &sy);
+	x += sx;
+	y += sy;
+	calculateBaseUnits(textfield, &baseX, &baseY, &unused);
+	width = MulDiv(width, baseX, 4);
+	height = MulDiv(height, baseY, 8);
+	if (MoveWindow(textfield, x, y, width, height, TRUE) == 0)
+		xpanic("error moving Area TextField in Area.OpenTextFieldAt()", GetLastError());
+	ShowWindow(textfield, SW_SHOW);
+	if (SetFocus(textfield) == NULL)
+		xpanic("error giving Area TextField focus", GetLastError());
+}
+
+void areaMarkTextFieldDone(HWND area)
+{
+	SetWindowLongPtrW(area, 0, (LONG_PTR) NULL);
+}

redo/area_windows.go

@@ -20,6 +20,7 @@ type area struct {
 	clickCounter	*clickCounter
 
 	textfield		C.HWND
+	textfielddone	*event
 }
 
 func makeAreaWindowClass() error {
@@ -36,10 +37,11 @@ func newArea(ab *areabase) Area {
 	a := &area{
 		areabase:		ab,
 		clickCounter:	new(clickCounter),
+		textfielddone:	newEvent(),
 	}
 	a._hwnd = C.newArea(unsafe.Pointer(a))
 	a.SetSize(a.width, a.height)
-	a.textfield = C.newAreaTextField(a._hwnd)
+	a.textfield = C.newAreaTextField(a._hwnd, unsafe.Pointer(a))
 	C.controlSetControlFont(a.textfield)
 	return a
 }
@@ -76,9 +78,7 @@ 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
+	C.areaOpenTextField(a._hwnd, a.textfield, C.int(x), C.int(y), textfieldWidth, textfieldHeight)
 }
 
 func (a *area) TextFieldText() string {
@@ -88,12 +88,17 @@ func (a *area) TextFieldText() string {
 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
+	a.textfielddone.set(f)
+}
+
+//export areaTextFieldDone
+func areaTextFieldDone(data unsafe.Pointer) {
+	a := (*area)(data)
+	C.areaMarkTextFieldDone(a._hwnd)
+	a.textfielddone.fire()
 }
 
 //export doPaint

redo/winapi_windows.h

@@ -124,12 +124,14 @@ extern DWORD makeContainerWindowClass(char **);
 extern HWND newContainer(void *);
 extern void calculateBaseUnits(HWND, int *, int *, LONG *);
 
-// area_window.c
+// area_windows.c
 #define areaWindowClass L"gouiarea"
 extern void repaintArea(HWND, RECT *);
 extern DWORD makeAreaWindowClass(char **);
 extern HWND newArea(void *);
-extern HWND newAreaTextField(HWND);
+extern HWND newAreaTextField(HWND, void *);
+extern void areaOpenTextField(HWND, HWND, int, int, int, int);
+extern void areaMarkTextFieldDone(HWND);
 
 // imagelist_windows.c
 extern HBITMAP unscaledBitmap(void *, intptr_t, intptr_t);