lablgtk_20001129* created

[helm.git] / helm / DEVEL / lablgtk / lablgtk_20001129-0.1.0 / gUtil.mli

diff --git a/helm/DEVEL/lablgtk/lablgtk_20001129-0.1.0/gUtil.mli b/helm/DEVEL/lablgtk/lablgtk_20001129-0.1.0/gUtil.mli
new file mode 100644 (file)
index 0000000..cd88d86
--- /dev/null
+++ b/helm/DEVEL/lablgtk/lablgtk_20001129-0.1.0/gUtil.mli
@@ -0,0 +1,109 @@
+(* $Id$ *)
+
+open GObj
+
+(* The memo class provides an easy way to remember the real class of
+   a widget.
+   Insert all widgets of class in one single t memo, and you can then
+   recover their original ML object with #find.
+*)
+
+class ['a] memo : unit ->
+  object
+    constraint 'a = #widget
+    val tbl : (int, 'a) Hashtbl.t
+    method add : 'a -> unit
+    method find : widget -> 'a
+    method remove : widget -> unit
+  end
+
+(* The ML signal mechanism allows one to add GTK-like signals to
+   arbitrary objects.
+*)
+
+val next_callback_id : unit -> GtkSignal.id
+
+class ['a] signal :
+  unit ->
+  object
+    val mutable callbacks : (GtkSignal.id * ('a -> unit)) list
+    method callbacks : (GtkSignal.id * ('a -> unit)) list
+    method call : 'a -> unit
+    method connect : after:bool -> callback:('a -> unit) -> GtkSignal.id
+    method disconnect : GtkSignal.id -> bool
+  end
+(* As with GTK signals, you can use [GtkSignal.stop_emit] inside a
+   callback to prevent other callbacks from being called. *)
+
+class virtual ml_signals : (GtkSignal.id -> bool) list ->
+  object ('a)
+    val after : bool
+    method after : 'a
+    method disconnect : GtkSignal.id -> unit
+    val mutable disconnectors : (GtkSignal.id -> bool) list
+  end
+class virtual add_ml_signals :
+  'a Gtk.obj -> (GtkSignal.id -> bool) list ->
+  object
+    method disconnect : GtkSignal.id -> unit
+    val mutable disconnectors : (GtkSignal.id -> bool) list
+  end
+
+(* To add ML signals to a LablGTK object:
+
+   class mywidget_signals obj ~mysignal1 ~mysignal2 = object
+     inherit somewidget_signals obj
+     inherit add_ml_signals obj [mysignal1#disconnect; mysignal2#disconnect]
+     method mysignal1 = mysignal1#connect ~after
+     method mysignal2 = mysignal2#connect ~after
+   end
+
+   class mywidget obj = object (self)
+     inherit somewidget obj
+     val mysignal1 = new signal obj
+     val mysignal2 = new signal obj
+     method connect = new mywidget_signals obj ~mysignal1 ~mysignal2
+     method call1 = mysignal1#call
+     method call2 = mysignal2#call
+   end
+
+   You can also add ML signals to an arbitrary object; just inherit
+   from [ml_signals] in place of [widget_signals]+[add_ml_signals].
+
+   class mysignals ~mysignal1 ~mysignal2 = object
+     inherit ml_signals [mysignal1#disconnect; mysignal2#disconnect]
+     method mysignal1 = mysignal1#connect ~after
+     method mysignal2 = mysignal2#connect ~after
+   end
+*)
+
+(* The variable class provides an easy way to propagate state modifications.
+   A new variable is created by [new variable init]. The [#set] method just
+   calls the [set] signal, which by default only calls [real_set].
+   [real_set] sets the variable and calls [changed] when needed.
+   Deep equality is used to compare values, but check is only done if
+   there are callbacks for [changed].
+*)
+
+class ['a] variable_signals :
+  set:'a signal -> changed:'a signal ->
+  object ('b)
+    val after : bool
+    method after : 'b
+    method set : callback:('a -> unit) -> GtkSignal.id
+    method changed : callback:('a -> unit) -> GtkSignal.id
+    method disconnect : GtkSignal.id -> unit
+    val mutable disconnectors : (GtkSignal.id -> bool) list
+  end
+
+class ['a] variable : 'a ->
+  object
+    val set : 'a signal
+    val changed : 'a signal
+    val mutable x : 'a
+    method connect : 'a variable_signals
+    method get : 'a
+    method set : 'a -> unit
+    method private equal : 'a -> 'a -> bool
+    method private real_set : 'a -> unit
+  end