apprt/gtk: add gtk-tabs-location=hidden

This is only supported on libadwaita. Instead of the normal tab overview
button, we will use an AdwTabButton[0].

Link: https://gnome.pages.gitlab.gnome.org/libadwaita/doc/1.6/class.TabButton.html [0]
Signed-off-by: Tristan Partin <tristan@partin.io>

src/apprt/gtk/Window.zig

@@ -120,9 +120,13 @@ pub fn init(self: *Window, app: *App) !void {
     // Create our box which will hold our widgets in the main content area.
     const box = c.gtk_box_new(c.GTK_ORIENTATION_VERTICAL, 0);
 
+    // Setup our notebook
+    self.notebook = Notebook.create(self);
+
     // If we are using an AdwWindow then we can support the tab overview.
     self.tab_overview = if (self.isAdwWindow()) overview: {
         const tab_overview = c.adw_tab_overview_new();
+        c.adw_tab_overview_set_view(@ptrCast(tab_overview), self.notebook.adw_tab_view);
         c.adw_tab_overview_set_enable_new_tab(@ptrCast(tab_overview), 1);
         _ = c.g_signal_connect_data(
             tab_overview,
@@ -170,18 +174,34 @@ pub fn init(self: *Window, app: *App) !void {
             if (comptime !adwaita.versionAtLeast(1, 4, 0)) unreachable;
             assert(self.isAdwWindow());
 
-            const btn = c.gtk_toggle_button_new();
+            const btn = btn: {
-            c.gtk_widget_set_tooltip_text(btn, "Show Open Tabs");
+                switch (app.config.@"gtk-tabs-location") {
-            c.gtk_button_set_icon_name(@ptrCast(btn), "view-grid-symbolic");
+                    .top, .bottom, .left, .right => {
+                        const btn = c.gtk_toggle_button_new();
+                        c.gtk_widget_set_tooltip_text(btn, "Show Open Tabs");
+                        c.gtk_button_set_icon_name(@ptrCast(btn), "view-grid-symbolic");
+                        _ = c.g_object_bind_property(
+                            btn,
+                            "active",
+                            tab_overview,
+                            "open",
+                            c.G_BINDING_BIDIRECTIONAL | c.G_BINDING_SYNC_CREATE,
+                        );
+
+                        break :btn btn;
+                    },
+                    .hidden => {
+                        const btn = c.adw_tab_button_new();
+                        c.adw_tab_button_set_view(@ptrCast(btn), self.notebook.adw_tab_view);
+                        c.gtk_actionable_set_action_name(@ptrCast(btn), "overview.open");
+
+                        break :btn btn;
+                    },
+                }
+            };
+
             c.gtk_widget_set_focus_on_click(btn, c.FALSE);
             c.adw_header_bar_pack_end(@ptrCast(header), btn);
-            _ = c.g_object_bind_property(
-                btn,
-                "active",
-                tab_overview,
-                "open",
-                c.G_BINDING_BIDIRECTIONAL | c.G_BINDING_SYNC_CREATE,
-            );
         }
 
         {
@@ -225,9 +245,6 @@ pub fn init(self: *Window, app: *App) !void {
         c.gtk_box_append(@ptrCast(box), warning_box);
     }
 
-    // Setup our notebook
-    self.notebook = Notebook.create(self);
-
     // Setup our toast overlay if we have one
     self.toast_overlay = if (adwaita.enabled(&self.app.config)) toast: {
         const toast_overlay = c.adw_toast_overlay_new();
@@ -279,16 +296,20 @@ pub fn init(self: *Window, app: *App) !void {
 
         const header_widget: *c.GtkWidget = @ptrCast(@alignCast(self.header.?));
         c.adw_toolbar_view_add_top_bar(toolbar_view, header_widget);
-        const tab_bar = c.adw_tab_bar_new();
-        c.adw_tab_bar_set_view(tab_bar, self.notebook.adw_tab_view);
 
-        if (!app.config.@"gtk-wide-tabs") c.adw_tab_bar_set_expand_tabs(tab_bar, 0);
+        if (self.app.config.@"gtk-tabs-location" != .hidden) {
+            const tab_bar = c.adw_tab_bar_new();
+            c.adw_tab_bar_set_view(tab_bar, self.notebook.adw_tab_view);
 
-        const tab_bar_widget: *c.GtkWidget = @ptrCast(@alignCast(tab_bar));
+            if (!app.config.@"gtk-wide-tabs") c.adw_tab_bar_set_expand_tabs(tab_bar, 0);
-        switch (self.app.config.@"gtk-tabs-location") {
+
-            // left and right is not supported in libadwaita.
+            const tab_bar_widget: *c.GtkWidget = @ptrCast(@alignCast(tab_bar));
-            .top, .left, .right => c.adw_toolbar_view_add_top_bar(toolbar_view, tab_bar_widget),
+            switch (self.app.config.@"gtk-tabs-location") {
-            .bottom => c.adw_toolbar_view_add_bottom_bar(toolbar_view, tab_bar_widget),
+                // left and right are not supported in libadwaita.
+                .top, .left, .right => c.adw_toolbar_view_add_top_bar(toolbar_view, tab_bar_widget),
+                .bottom => c.adw_toolbar_view_add_bottom_bar(toolbar_view, tab_bar_widget),
+                .hidden => unreachable,
+            }
         }
         c.adw_toolbar_view_set_content(toolbar_view, box);
 
@@ -322,15 +343,16 @@ pub fn init(self: *Window, app: *App) !void {
                 @ptrCast(@alignCast(toolbar_view)),
             );
         }
-    } else {
+    } else tab_bar: {
         switch (self.notebook) {
             .adw_tab_view => |tab_view| if (comptime adwaita.versionAtLeast(0, 0, 0)) {
+                if (app.config.@"gtk-tabs-location" == .hidden) break :tab_bar;
+
                 // In earlier adwaita versions, we need to add the tabbar manually since we do not use
                 // an AdwToolbarView.
                 const tab_bar: *c.AdwTabBar = c.adw_tab_bar_new().?;
                 c.gtk_widget_add_css_class(@ptrCast(@alignCast(tab_bar)), "inline");
                 switch (app.config.@"gtk-tabs-location") {
-                    // left and right is not supported in libadwaita.
                     .top,
                     .left,
                     .right,
@@ -343,12 +365,11 @@ pub fn init(self: *Window, app: *App) !void {
                         @ptrCast(box),
                         @ptrCast(@alignCast(tab_bar)),
                     ),
+                    .hidden => unreachable,
                 }
                 c.adw_tab_bar_set_view(tab_bar, tab_view);
 
-                if (!app.config.@"gtk-wide-tabs") {
+                if (!app.config.@"gtk-wide-tabs") c.adw_tab_bar_set_expand_tabs(tab_bar, 0);
-                    c.adw_tab_bar_set_expand_tabs(tab_bar, 0);
-                }
             },
 
             .gtk_notebook => {},

src/apprt/gtk/notebook.zig

@@ -29,7 +29,7 @@ pub const Notebook = union(enum) {
         const notebook_widget: *c.GtkWidget = c.gtk_notebook_new();
         const notebook: *c.GtkNotebook = @ptrCast(notebook_widget);
         const notebook_tab_pos: c_uint = switch (app.config.@"gtk-tabs-location") {
-            .top => c.GTK_POS_TOP,
+            .top, .hidden => c.GTK_POS_TOP,
             .bottom => c.GTK_POS_BOTTOM,
             .left => c.GTK_POS_LEFT,
             .right => c.GTK_POS_RIGHT,

src/config/Config.zig

@@ -1727,10 +1727,17 @@ keybind: Keybinds = .{},
 @"gtk-titlebar": bool = true,
 
 /// Determines the side of the screen that the GTK tab bar will stick to.
-/// Top, bottom, left, and right are supported. The default is top.
+/// Top, bottom, left, right, and hidden are supported. The default is top.
 ///
 /// If this option has value `left` or `right` when using Adwaita, it falls
-/// back to `top`.
+/// back to `top`. `hidden`, meaning that tabs don't exist, is not supported
+/// without using Adwaita, falling back to `top`.
+///
+/// When `hidden` is set and Adwaita is enabled, a tab button displaying the
+/// number of tabs will appear in the title bar. It has the ability to open a
+/// tab overview for displaying tabs. Alternatively, you can use the
+/// `toggle_tab_overview` action in a keybind if your window doesn't have a
+/// title bar, or you can switch tabs with keybinds.
 @"gtk-tabs-location": GtkTabsLocation = .top,
 
 /// Determines the appearance of the top and bottom bars when using the
@@ -4854,6 +4861,7 @@ pub const GtkTabsLocation = enum {
     bottom,
     left,
     right,
+    hidden,
 };
 
 /// See adw-toolbar-style