Do not use save button for readonly screen

Even if save_current is set, a readonly screen is never saved on response.

Closes #12538

sao/src/window.js

@@ -179,8 +179,7 @@
                 }
             });
 
-            var readonly = (this.screen.attributes.readonly ||
-                    this.screen.group.readonly);
+            var readonly = this.screen.readonly || this.screen.group.readonly;
 
             this.but_ok = null;
             this.but_new = null;
@@ -223,7 +222,7 @@
                 }));
             }
 
-            if (this.save_current) {
+            if (this.save_current && !readonly) {
                 this.but_ok = jQuery('<button/>', {
                     'class': 'btn btn-primary',
                     'type': 'submit',
@@ -396,7 +395,7 @@
             var name = '_';
             var access = Sao.common.MODELACCESS.get(this.screen.model_name);
             var deletable = this.screen.deletable;
-            var readonly = this.screen.group.readonly || this.screen.readonly;
+            var readonly = this.screen.readonly || this.screen.group.readonly;
             if (position >= 1) {
                 name = position;
                 if (this.domain) {
@@ -486,7 +485,7 @@
         response: function(response_id) {
             var result;
             this.screen.current_view.set_value();
-            var readonly = this.screen.group.readonly;
+            var readonly = this.screen.readonly || this.screen.group.readonly;
             if (~['RESPONSE_OK', 'RESPONSE_ACCEPT'].indexOf(response_id) &&
                     !readonly &&
                     this.screen.current_record) {

tryton/tryton/gui/window/win_form.py

@@ -101,7 +101,7 @@ class WinForm(NoModal, InfoBar):
             self.but_new.set_always_show_image(True)
             self.but_new.set_accel_path('<tryton>/Form/New', self.accel_group)
 
-        if self.save_current:
+        if self.save_current and not readonly:
             self.but_ok = Gtk.Button(label=_('_Save'), use_underline=True)
             self.but_ok.set_image(common.IconFactory.get_image(
                     'tryton-save', Gtk.IconSize.BUTTON))
@@ -353,7 +353,7 @@ class WinForm(NoModal, InfoBar):
         deletable = True
         if self.screen.current_record:
             deletable = self.screen.current_record.deletable
-        readonly = self.screen.group.readonly
+        readonly = self.screen.readonly or self.screen.group.readonly
         if position >= 1:
             name = str(position)
             if self.domain is not None:
@@ -401,7 +401,7 @@ class WinForm(NoModal, InfoBar):
         cancel_responses = [
             Gtk.ResponseType.CANCEL, Gtk.ResponseType.DELETE_EVENT]
         self.screen.current_view.set_value()
-        readonly = self.screen.group.readonly
+        readonly = self.screen.readonly or self.screen.group.readonly
         if (response_id not in cancel_responses
                 and not readonly
                 and self.screen.current_record is not None):