("inline_editing_started", "inline_editing_finished"): new signals

New signals added to the canvas view, so that GPS can invalidate the
current context whenever something occurs on the canvas that might
change which actions are applicable.

When an item is edited inline, and moved at the time, we now also
move the editing widget to keep overlapping the item.

Change-Id: I458ef32a90e607aa3e86bd588d1c0ea62cbfa69e

Author: briot

features-17

@@ -13,6 +13,21 @@ of the feature.
 New features in GtkAda 17
 -------------------------
 
+NF-17-P930-028 Gtkada.Canvas_View: inline editing improvements (2016-09-30)
+
+   New signals have been aded:
+      Signal_Inline_Editing_Started
+      Signal_Inline_Editing_Finished
+   New subprograms have been added:
+      Set_Editable, Is_Editable
+      Inline_Editing_In_Progress
+   When an item that is edited interactively by the user is moved, we now
+   also move the editing widget (generally a GtkTextView). This text view
+   now also inherits the font size and attributes from the edited item.
+   End of editing is done via a simple <return>, since the previous
+   <ctrl-return> was impossible to guess by the user. Preselect the whole
+   text when editing, so that the user can more easily change it all.
+
 NF-17-P722-028 New MDI child signals (2016-07-22)
 
    New signals have been introduced in the MDI

src/gtkada-canvas_view-views.adb

@@ -310,10 +310,10 @@ package body Gtkada.Canvas_View.Views is
    ---------------------------
 
    procedure Cancel_Inline_Editing
-     (Self    : not null access Canvas_View_Record'Class)
-   is
+     (Self    : not null access Canvas_View_Record'Class) is
    begin
       if Self.Inline_Edit.Item /= null then
+         Self.Inline_Editing_Finished (Self.Inline_Edit.Item);
          Self.Inline_Edit.Item := null;
          Self.Remove (Self.Get_Child);
       end if;
@@ -347,6 +347,7 @@ package body Gtkada.Canvas_View.Views is
          Self.Add (W);  --  also queues a resize, so calls On_Size_Allocate
          W.Show_All;
          W.Grab_Focus;
+         Self.Inline_Editing_Started (Item);
       end if;
    end Start_Inline_Editing;
 

src/gtkada-canvas_view.adb

@@ -69,7 +69,9 @@ package body Gtkada.Canvas_View is
       4 => New_String (String (Signal_Item_Destroyed)));
    View_Signals : constant Gtkada.Types.Chars_Ptr_Array :=
      (1 => New_String (String (Signal_Viewport_Changed)),
-      2 => New_String (String (Signal_Item_Event)));
+      2 => New_String (String (Signal_Item_Event)),
+      3 => New_String (String (Signal_Inline_Editing_Started)),
+      4 => New_String (String (Signal_Inline_Editing_Finished)));
 
    Model_Class_Record : Glib.Object.Ada_GObject_Class :=
      Glib.Object.Uninitialized_Class;
@@ -102,6 +104,10 @@ package body Gtkada.Canvas_View is
    pragma Convention (C, On_Size_Allocate);
    --  default handler for "size_allocate" on views.
 
+   procedure Move_Inline_Edit_Widget
+     (Self : not null access Canvas_View_Record'Class);
+   --  Move the inline editing widget, if one exists
+
    function GValue_To_Abstract_Item (Value : GValue) return Abstract_Item;
    function Abstract_Item_To_Address is new Ada.Unchecked_Conversion
      (Abstract_Item, System.Address);
@@ -508,6 +514,8 @@ package body Gtkada.Canvas_View is
          Set_Adjustment_Values (Self);
          Self.Queue_Draw;
       end if;
+
+      Move_Inline_Edit_Widget (Self);
    end On_Layout_Changed_For_View;
 
    -----------------------------------
@@ -1136,7 +1144,9 @@ package body Gtkada.Canvas_View is
          Class_Record => View_Class_Record'Access,
          Type_Name    => "GtkadaCanvasView",
          Parameters   => (1 => (1 => GType_None),
-                          2 => (1 => GType_Pointer)),
+                          2 => (1 => GType_Pointer),
+                          3 => (1 => GType_Pointer),
+                          4 => (1 => GType_Pointer)),
          Returns      => (1 => GType_None,
                           2 => GType_Boolean),
          Class_Init   => View_Class_Init'Access)
@@ -1357,6 +1367,36 @@ package body Gtkada.Canvas_View is
          return 0;
    end On_View_Draw;
 
+   -----------------------------
+   -- Move_Inline_Edit_Widget --
+   -----------------------------
+
+   procedure Move_Inline_Edit_Widget
+      (Self : not null access Canvas_View_Record'Class)
+   is
+      Edit   : Gtk_Widget;
+      Box    : View_Rectangle;
+      SAlloc : Gtk_Allocation;
+      WMin, WNat, HMin, HNat : Gint;
+   begin
+      if Self.Inline_Edit.Item /= null then
+         Edit := Self.Get_Child;
+         Box := Self.Model_To_View (Self.Inline_Edit.Item.Model_Bounding_Box);
+
+         --  SAlloc is relative to the view, so we should not add Alloc.{X,Y}
+         SAlloc.X := Gint (Box.X);
+         SAlloc.Y := Gint (Box.Y);
+
+         Edit.Get_Preferred_Height (HMin, HNat);
+         SAlloc.Height := Gint'Max (HMin, Gint (Box.Height));
+
+         Edit.Get_Preferred_Width_For_Height (SAlloc.Height, WMin, WNat);
+         SAlloc.Width := Gint'Max (WMin, Gint (Box.Width));
+
+         Edit.Size_Allocate (SAlloc);
+      end if;
+   end Move_Inline_Edit_Widget;
+
    ----------------------
    -- On_Size_Allocate --
    ----------------------
@@ -1366,9 +1406,6 @@ package body Gtkada.Canvas_View is
    is
       Self : constant Canvas_View := Canvas_View (Glib.Object.Convert (View));
       SAlloc : Gtk_Allocation := Alloc;
-      Edit   : Gtk_Widget;
-      Box    : View_Rectangle;
-      WMin, WNat, HMin, HNat : Gint;
    begin
       --  For some reason, when we maximize the toplevel window in testgtk, or
       --  at least enlarge it horizontally, we are starting to see an alloc
@@ -1393,22 +1430,7 @@ package body Gtkada.Canvas_View is
       end if;
 
       --  Are we in the middle of inline-editing ?
-      if Self.Inline_Edit.Item /= null then
-         Edit := Self.Get_Child;
-         Box := Self.Model_To_View (Self.Inline_Edit.Item.Model_Bounding_Box);
-
-         --  SAlloc is relative to the view, so we should not add Alloc.{X,Y}
-         SAlloc.X := Gint (Box.X);
-         SAlloc.Y := Gint (Box.Y);
-
-         Edit.Get_Preferred_Height (HMin, HNat);
-         SAlloc.Height := Gint'Max (HMin, Gint (Box.Height));
-
-         Edit.Get_Preferred_Width_For_Height (SAlloc.Height, WMin, WNat);
-         SAlloc.Width := Gint'Max (WMin, Gint (Box.Width));
-
-         Edit.Size_Allocate (SAlloc);
-      end if;
+      Move_Inline_Edit_Widget (Self);
 
       if Self.Scale_To_Fit_Requested /= 0.0 then
          Self.Scale_To_Fit
@@ -1830,6 +1852,76 @@ package body Gtkada.Canvas_View is
       end if;
    end On_Item_Event;
 
+   ----------------------------
+   -- Inline_Editing_Started --
+   ----------------------------
+
+   procedure Inline_Editing_Started
+     (Self   : not null access Canvas_View_Record'Class;
+      Item : not null access Abstract_Item_Record'Class) is
+   begin
+      Abstract_Item_Emit
+        (Self, Signal_Inline_Editing_Started & ASCII.NUL,
+         Abstract_Item (Item));
+   end Inline_Editing_Started;
+
+   -------------------------------
+   -- On_Inline_Editing_Started --
+   -------------------------------
+
+   function On_Inline_Editing_Started
+     (Self : not null access Canvas_View_Record'Class;
+      Call : not null access procedure
+        (Self : access GObject_Record'Class; Item : Abstract_Item);
+      Slot : access GObject_Record'Class := null)
+      return Gtk.Handlers.Handler_Id is
+   begin
+      if Slot = null then
+         return Object_Callback.Connect
+           (Self, Signal_Inline_Editing_Started,
+            Abstract_Item_Marshallers.To_Marshaller (Call));
+      else
+         return Object_Callback.Object_Connect
+           (Self, Signal_Inline_Editing_Started,
+            Abstract_Item_Marshallers.To_Marshaller (Call), Slot);
+      end if;
+   end On_Inline_Editing_Started;
+
+   -----------------------------
+   -- Inline_Editing_Finished --
+   -----------------------------
+
+   procedure Inline_Editing_Finished
+     (Self  : not null access Canvas_View_Record'Class;
+      Item : not null access Abstract_Item_Record'Class) is
+   begin
+      Abstract_Item_Emit
+        (Self, Signal_Inline_Editing_Finished & ASCII.NUL,
+         Abstract_Item (Item));
+   end Inline_Editing_Finished;
+
+   --------------------------------
+   -- On_Inline_Editing_Finished --
+   --------------------------------
+
+   function On_Inline_Editing_Finished
+     (Self : not null access Canvas_View_Record'Class;
+      Call : not null access procedure
+        (Self : access GObject_Record'Class; Item : Abstract_Item);
+      Slot : access GObject_Record'Class := null)
+      return Gtk.Handlers.Handler_Id is
+   begin
+      if Slot = null then
+         return Object_Callback.Connect
+           (Self, Signal_Inline_Editing_Finished,
+            Abstract_Item_Marshallers.To_Marshaller (Call));
+      else
+         return Object_Callback.Object_Connect
+           (Self, Signal_Inline_Editing_Finished,
+            Abstract_Item_Marshallers.To_Marshaller (Call), Slot);
+      end if;
+   end On_Inline_Editing_Finished;
+
    -------------
    -- Refresh --
    -------------

src/gtkada-canvas_view.ads

@@ -1295,6 +1295,33 @@ package Gtkada.Canvas_View is
    --  compatible callbacks which enable behaviors such as a moving items,
    --  scrolling the canvas by dragging the background,...
 
+   procedure Inline_Editing_Started
+     (Self : not null access Canvas_View_Record'Class;
+      Item : not null access Abstract_Item_Record'Class);
+   function On_Inline_Editing_Started
+     (Self : not null access Canvas_View_Record'Class;
+      Call : not null access procedure
+        (Self : access GObject_Record'Class; Item : Abstract_Item);
+      Slot : access GObject_Record'Class := null)
+      return Gtk.Handlers.Handler_Id;
+   Signal_Inline_Editing_Started : constant Glib.Signal_Name :=
+      "inline_editing_started";
+   --  Called when the user starts inline editing of items.
+
+   procedure Inline_Editing_Finished
+     (Self : not null access Canvas_View_Record'Class;
+      Item : not null access Abstract_Item_Record'Class);
+   function On_Inline_Editing_Finished
+     (Self : not null access Canvas_View_Record'Class;
+      Call : not null access procedure
+        (Self : access GObject_Record'Class; Item : Abstract_Item);
+      Slot : access GObject_Record'Class := null)
+      return Gtk.Handlers.Handler_Id;
+   Signal_Inline_Editing_Finished : constant Glib.Signal_Name :=
+      "inline_editing_finished";
+   --  Called when the user finishes (cancels ot validates) inline
+   --  editing of items.
+
    ------------------------
    -- Object hierarchies --
    ------------------------