diff --git a/declarative/dialog.go b/declarative/dialog.go
index ca6fee4b..915ba1fa 100644
--- a/declarative/dialog.go
+++ b/declarative/dialog.go
@@ -31,10 +31,19 @@ type Dialog struct {
 	Children         []Widget
 	DefaultButton    **walk.PushButton
 	CancelButton     **walk.PushButton
+	FixedSize        bool
 }
 
 func (d Dialog) Create(owner walk.Form) error {
-	w, err := walk.NewDialog(owner)
+	var w *walk.Dialog
+	var err error
+
+	if d.FixedSize {
+		w, err = walk.NewDialogWithFixedSize(owner)
+	} else {
+		w, err = walk.NewDialog(owner)
+	}
+
 	if err != nil {
 		return err
 	}
@@ -86,7 +95,9 @@ func (d Dialog) Create(owner walk.Form) error {
 			}
 
 			if db := *d.DataBinder.AssignTo; db != nil {
-				(*d.DefaultButton).SetEnabled(db.CanSubmit())
+				if db.DataSource() != nil {
+					(*d.DefaultButton).SetEnabled(db.CanSubmit())
+				}
 
 				db.CanSubmitChanged().Attach(func() {
 					(*d.DefaultButton).SetEnabled(db.CanSubmit())
diff --git a/dialog.go b/dialog.go
index e039bbe2..ef9a3025 100644
--- a/dialog.go
+++ b/dialog.go
@@ -49,6 +49,14 @@ type Dialog struct {
 }
 
 func NewDialog(owner Form) (*Dialog, error) {
+	return newDialogWithStyle(owner, win.WS_THICKFRAME)
+}
+
+func NewDialogWithFixedSize(owner Form) (*Dialog, error) {
+	return newDialogWithStyle(owner, 0)
+}
+
+func newDialogWithStyle(owner Form, style uint32) (*Dialog, error) {
 	dlg := &Dialog{
 		FormBase: FormBase{
 			owner: owner,
@@ -59,7 +67,7 @@ func NewDialog(owner Form) (*Dialog, error) {
 		dlg,
 		owner,
 		dialogWindowClass,
-		win.WS_CAPTION|win.WS_SYSMENU|win.WS_THICKFRAME,
+		win.WS_CAPTION|win.WS_SYSMENU|style,
 		win.WS_EX_DLGMODALFRAME); err != nil {
 		return nil, err
 	}