[gnome-contacts] ContactList: only show checkbox on hover.

[Niels De Graef <nielsdg src gnome org>]

commit f36cc8e5fa1b867fe3181f6cf30505fdfedfce56
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Sun Jan 21 11:23:12 2018 +0100

    ContactList: only show checkbox on hover.
    
    * Removed the select_button in ContactWindow (as selection_mode is
    implicitly started by selecting a checkbox).
    * Updated the cancel_select_button with a new icon (complying with the
    new mockups).

 data/ui/contacts-window.ui     |   23 +++---------------
 src/contacts-contact-list.vala |   51 +++++++++++++++++++++++++++++-----------
 src/contacts-window.vala       |    4 ---
 3 files changed, 41 insertions(+), 37 deletions(-)
---
diff --git a/data/ui/contacts-window.ui b/data/ui/contacts-window.ui
index 2294701..7571709 100644
--- a/data/ui/contacts-window.ui
+++ b/data/ui/contacts-window.ui
@@ -53,20 +53,16 @@
               </packing>
             </child>
             <child>
-              <object class="GtkButton" id="select_button">
-                <property name="visible">True</property>
+              <object class="GtkButton" id="select_cancel_button">
+                <property name="visible">False</property>
                 <property name="can_focus">True</property>
                 <property name="focus_on_click">False</property>
-                <child internal-child="accessible">
-                  <object class="AtkObject" id="select_button_atkobject">
-                    <property name="AtkObject::accessible-name" translatable="yes">Selection mode</property>
-                  </object>
-                </child>
                 <child>
                   <object class="GtkImage">
                     <property name="visible">True</property>
                     <property name="can_focus">False</property>
-                    <property name="icon_name">object-select-symbolic</property>
+                    <property name="icon_name">edit-clear-symbolic</property>
+                    <property name="icon_size">1</property>
                   </object>
                 </child>
               </object>
@@ -74,17 +70,6 @@
                 <property name="pack_type">end</property>
               </packing>
             </child>
-            <child>
-              <object class="GtkButton" id="select_cancel_button">
-                <property name="visible">False</property>
-                <property name="can_focus">True</property>
-                <property name="focus_on_click">False</property>
-                <property name="label" translatable="yes">Cancel</property>
-              </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
-            </child>
           </object>
         </child>
         <child>
diff --git a/src/contacts-contact-list.vala b/src/contacts-contact-list.vala
index 80cf036..99efa95 100644
--- a/src/contacts-contact-list.vala
+++ b/src/contacts-contact-list.vala
@@ -32,6 +32,8 @@ public class Contacts.ContactList : ListBox {
     public Label label;
     private Avatar avatar;
     public CheckButton selector_button;
+    // Whether the selector should always be visible (or only on hover)
+    private bool checkbox_exposed = false;
     public bool filtered;
 
     public ContactDataRow(Contact c) {
@@ -69,6 +71,22 @@ public class Contacts.ContactList : ListBox {
       this.label.set_text (this.contact.display_name);
       this.avatar.set_image.begin (this.contact.individual, this.contact);
     }
+
+    // Sets whether the checbox should always be shown (and not only on hover)
+    public void expose_checkbox (bool expose) {
+      this.checkbox_exposed = expose;
+      this.selector_button.visible = expose;
+    }
+
+    // Normally, we would use the (enter/leave)_notify_event here, but since ListBoxRow
+    // doesn't have its own Gdk.Window, this won't work (at least in GTK+3).
+    public override void state_flags_changed (StateFlags previous_state) {
+      var hovering_now = StateFlags.PRELIGHT in get_state_flags ();
+      var was_hovering = StateFlags.PRELIGHT in previous_state;
+
+      if (hovering_now != was_hovering) // If hovering changed
+        this.selector_button.visible = checkbox_exposed || hovering_now;
+    }
   }
 
   public signal void selection_changed (Contact? contact);
@@ -107,7 +125,7 @@ public class Contacts.ContactList : ListBox {
   private void on_ui_state_changed () {
     foreach (var widget in get_children ()) {
       var row = widget as ContactDataRow;
-      row.selector_button.visible = (this.state == UiState.SELECTING);
+      row.expose_checkbox (this.state == UiState.SELECTING);
 
       if (this.state != UiState.SELECTING)
         row.selector_button.active = false;
@@ -211,23 +229,28 @@ public class Contacts.ContactList : ListBox {
   }
 
   private void contact_added_cb (Store store, Contact c) {
-    var data =  new ContactDataRow(c);
+    var row =  new ContactDataRow(c);
+    row.update_data (calculate_filtered (c));
+    row.selector_button.toggled.connect ( () => { on_row_checkbox_toggled (row); });
+    row.selector_button.visible = (this.state == UiState.SELECTING);
 
-    data.update_data (calculate_filtered (c));
+    contacts[c] = row;
+    add (row);
+  }
 
-    data.selector_button.toggled.connect (() => {
-       if (data.selector_button.active)
-         this.nr_contacts_marked++;
-       else
-         this.nr_contacts_marked--;
+  private void on_row_checkbox_toggled (ContactDataRow row) {
+    this.nr_contacts_marked += (row.selector_button.active)? 1 : -1;
 
-       contacts_marked (this.nr_contacts_marked);
-      });
+    // User selected a first checkbox: enter selection mode
+    if (row.selector_button.active && this.nr_contacts_marked == 1)
+      this.state = UiState.SELECTING;
 
-    if (this.state != UiState.SELECTING)
-      data.selector_button.hide ();
-    contacts.set (c, data);
-    this.add (data);
+
+    // User deselected the last checkbox: leave selection mode
+    if (!row.selector_button.active && this.nr_contacts_marked == 0)
+      this.state = UiState.SHOWING;
+
+    contacts_marked (this.nr_contacts_marked);
   }
 
   private void contact_removed_cb (Store store, Contact c) {
diff --git a/src/contacts-window.vala b/src/contacts-window.vala
index 2b842b8..25ce666 100644
--- a/src/contacts-window.vala
+++ b/src/contacts-window.vala
@@ -38,8 +38,6 @@ public class Contacts.Window : Gtk.ApplicationWindow {
   [GtkChild]
   private Button add_button;
   [GtkChild]
-  private Button select_button;
-  [GtkChild]
   private Button select_cancel_button;
   [GtkChild]
   private ToggleButton favorite_button;
@@ -120,7 +118,6 @@ public class Contacts.Window : Gtk.ApplicationWindow {
     // UI when we're not editing of selecting stuff
     this.add_button.visible
         = this.right_header.show_close_button
-        = this.select_button.visible
         = (this.state == UiState.NORMAL || this.state == UiState.SHOWING);
 
     // UI when showing a contact
@@ -242,7 +239,6 @@ public class Contacts.Window : Gtk.ApplicationWindow {
   }
 
   private void connect_button_signals () {
-    this.select_button.clicked.connect (() => { this.state = UiState.SELECTING; });
     this.select_cancel_button.clicked.connect (() => { this.state = UiState.NORMAL; });
     this.done_button.clicked.connect (() => stop_editing ());
     this.cancel_button.clicked.connect (() => stop_editing (true));