Implemented TextField.ReadOnly() on Mac OS X. Began standardizing window class name access on Windows.

basicctrls_darwin.m

@@ -136,6 +136,7 @@ id newTextField(void)
 	NSTextField *t;
 
 	t = [[NSTextField alloc] initWithFrame:NSZeroRect];
+	[t setSelectable:YES];		// otherwise the setting is masked by the editable default of YES
 	return finishNewTextField((id) t, YES);
 }
 
@@ -144,6 +145,7 @@ id newPasswordField(void)
 	NSSecureTextField *t;
 
 	t = [[NSSecureTextField alloc] initWithFrame:NSZeroRect];
+	[t setSelectable:YES];		// otherwise the setting is masked by the editable default of YES
 	return finishNewTextField((id) t, YES);
 }
 
@@ -184,6 +186,16 @@ void textfieldCloseInvalidPopover(id popover)
 	// don't release; close does that already
 }
 
+BOOL textfieldEditable(id textfield)
+{
+	return [toNSTextField(textfield) isEditable];
+}
+
+void textfieldSetEditable(id textfield, BOOL editable)
+{
+	[toNSTextField(textfield) setEditable:editable];
+}
+
 id newLabel(void)
 {
 	NSTextField *l;

common_windows.c

@@ -100,7 +100,7 @@ void paintControlBackground(HWND hwnd, HDC dc)
 	HWND parent;
 	RECT r;
 	POINT p, pOrig;
-	WCHAR classname[128] = L"";		// more than enough to avoid collisions
+	WCHAR classname[maxClassName + 1] = L"";
 
 	parent = hwnd;
 	for (;;) {
@@ -110,7 +110,7 @@ void paintControlBackground(HWND hwnd, HDC dc)
 		// wine sends these messages early, yay...
 		if (parent == msgwin)
 			return;
-		if (GetClassNameW(parent, classname, 128) == 0)
+		if (GetClassNameW(parent, classname, maxClassName) == 0)
 			xpanic("error getting name of focused window class in paintControlBackground()", GetLastError());
 		// skip groupboxes; they're (supposed to be) transparent
 		if (_wcsicmp(classname, L"button") != 0)

objc_darwin.h

@@ -75,6 +75,8 @@ extern const char *textfieldText(id);
 extern void textfieldSetText(id, char *);
 extern id textfieldOpenInvalidPopover(id, char *);
 extern void textfieldCloseInvalidPopover(id);
+extern BOOL textfieldEditable(id);
+extern void textfieldSetEditable(id, BOOL);
 extern id newLabel(void);
 extern id newGroup(id);
 extern const char *groupText(id);

textfield_darwin.go

@@ -62,6 +62,16 @@ func (t *textfield) Invalid(reason string) {
 	t.invalid = C.textfieldOpenInvalidPopover(t.id, creason)
 }
 
+// note that the property here is editable, which is the opposite of read-only
+
+func (t *textfield) ReadOnly() bool {
+	return !fromBOOL(C.textfieldEditable(t.id))
+}
+
+func (t *textfield) SetReadOnly(readonly bool) {
+	C.textfieldSetEditable(t.id, toBOOL(!readonly))
+}
+
 //export textfieldChanged
 func textfieldChanged(data unsafe.Pointer) {
 	t := (*textfield)(data)

uitask_windows.c

@@ -3,10 +3,6 @@
 #include "winapi_windows.h"
 #include "_cgo_export.h"
 
-// note that this includes the terminating '\0'
-// this also assumes WC_TABCONTROL is longer than areaWindowClass
-#define NCLASSNAME (sizeof WC_TABCONTROL / sizeof WC_TABCONTROL[0])
-
 void uimsgloop_area(HWND active, HWND focus, MSG *msg)
 {
 	MSG copy;
@@ -63,7 +59,7 @@ void uimsgloop(void)
 	MSG msg;
 	int res;
 	HWND active, focus;
-	WCHAR classchk[NCLASSNAME];
+	WCHAR classchk[maxClassName + 1];
 	BOOL dodlgmessage;
 
 	for (;;) {
@@ -82,12 +78,9 @@ void uimsgloop(void)
 		// bit of logic involved here:
 		// we don't want dialog messages passed into Areas, so we don't call IsDialogMessageW() there
 		// as for Tabs, we can't have both WS_TABSTOP and WS_EX_CONTROLPARENT set at the same time, so we hotswap the two styles to get the behavior we want
-		// theoretically we could use the class atom to avoid a wcscmp()
-		// however, raymond chen advises against this - http://blogs.msdn.com/b/oldnewthing/archive/2004/10/11/240744.aspx (and we're not in control of the Tab class, before you say anything)
-		// we could also theoretically just send msgAreaDefocuses directly, but what DefWindowProc() does to a WM_APP message is undocumented
 		focus = GetFocus();
 		if (focus != NULL) {
-			if (GetClassNameW(focus, classchk, NCLASSNAME) == 0)
+			if (GetClassNameW(focus, classchk, maxClassName) == 0)
 				xpanic("error getting name of focused window class for Area check", GetLastError());
 			if (_wcsicmp(classchk, areaWindowClass) == 0) {
 				uimsgloop_area(active, focus, &msg);

winapi_windows.h

@@ -41,6 +41,13 @@ enum {
 	msgOpenFileDone,
 };
 
+// there are a number of places where we need to know what window class an arbitrary handle has
+// theoretically we could use the class atom to avoid a _wcsicmp()
+// however, raymond chen advises against this - http://blogs.msdn.com/b/oldnewthing/archive/2004/10/11/240744.aspx (and we're not in control of the Tab class, before you say anything)
+// MSDN says 256 is the maximum length of a class name; add a few characters just to be safe (because it doesn't say whether this includes the terminating null character)
+// TODO localize this to a helper function
+#define maxClassName 260
+
 // uitask_windows.c
 extern void uimsgloop(void);
 extern void issue(void *);