When implementing this design, we decided to reverse the order of the difficulty levels such that Easy appears on top and Very Hard on the bottom.

The icon to use for the back button is "go-previous-symbolic"

Created attachment 278268 [details] [review]
Simplify New Game Screen

The updated New Game screen looks like this - http://i.imgur.com/7X3z5DL.png

Review of attachment 278268 [details] [review]:

Yeah, removing code :)

Code that isn't written, can't have bugs. :)

Looks fine overall. Good Work.

::: data/gnome-sudoku.ui
@@ +129,3 @@
+                                <property name="use_underline">True</property>
+                                <property name="label" translatable="yes">_Hard</property>
+                                <property name="action-name">app.start-game</property>

I am not good with the UI stuff. Does this work with the mnemonics and stuff? Have you tried navigating this with the keyboard.

@@ +156,3 @@
+                        <property name="expand">True</property>
+                        <property name="fill">True</property>
+                        <!--<property name="padding">20</property>-->

The comment?

::: src/gnome-sudoku.vala
@@ +281,3 @@
+    private void start_game_cb (SimpleAction action, Variant? difficulty)
+    {
+        var selected_difficulty = (DifficultyCategory) difficulty.get_int32 ();

Can we add a comment here, where this comes from and that we sadly can't have the enum in the .ui-file. Could we also comment that in the ui-file, that the values correspond to the enum in this class?

Whenever we have such dependencies that we can't solve with a common data structure or type, we want to document that.

:)

Created attachment 278326 [details] [review]
Simplify New Game Screen

Patch updated.

> ::: data/gnome-sudoku.ui
> @@ +129,3 @@
> +                                <property name="use_underline">True</property>
> +                                <property name="label"
> translatable="yes">_Hard</property>
> +                                <property
> name="action-name">app.start-game</property>
> 
> I am not good with the UI stuff. Does this work with the mnemonics and stuff?
> Have you tried navigating this with the keyboard.

Yes, Alt+{E, M, H, V} work for {Easy, Medium, Hard, Very Hard}
Thats why the underscore before the character to be used as shortcut and 'use_underline' property set to True
 
> @@ +156,3 @@
> +                        <property name="expand">True</property>
> +                        <property name="fill">True</property>
> +                        <!--<property name="padding">20</property>-->
> 
> The comment?

Sorry !
removed.

> ::: src/gnome-sudoku.vala
> @@ +281,3 @@
> +    private void start_game_cb (SimpleAction action, Variant? difficulty)
> +    {
> +        var selected_difficulty = (DifficultyCategory) difficulty.get_int32
> ();
> 
> Can we add a comment here, where this comes from and that we sadly can't have
> the enum in the .ui-file. Could we also comment that in the ui-file, that the
> values correspond to the enum in this class?

Done.

This looks ready to commit; I guess it just got forgotten?

Comment on attachment 278326 [details] [review]
Simplify New Game Screen

Pushed as 85840ca