Changeset 216:48de87adead1

Timestamp:

05/17/08 17:23:22 (3 months ago)

Author:

Frank Benoit <benoit@tionex.de>

branch:

default

Message:

Add dgListener template function for the Listener class

Files:

• dwt/widgets/Listener.d (modified) (2 diffs)

dwt/widgets/Listener.d

@@ -14 +14 @@
-
-import dwt.widgets.Event;
+
+import tango.core.Traits;
+import tango.core.Tuple;
-
-/**
@@ -54 +57 @@
-void handleEvent (Event event);
-}
+
+
+/// Helper class for the dgListener template function
+private class _DgListenerT(Dg,T...) : Listener {
+
+    alias ParameterTupleOf!(Dg) DgArgs;
+    static assert( is(DgArgs == Tuple!(Event,T)),
+                "Delegate args not correct" );
+
+    Dg dg;
+    T  t;
+
+    private this( Dg dg, T t ){
+        this.dg = dg;
+        static if( T.length > 0 ){
+            this.t = t;
+        }
+    }
+
+    void handleEvent( Event e ){
+        dg(e,t);
+    }
+}
+
+/++
+ + dgListener creates a class implementing the Listener interface and delegating the call to
+ + handleEvent to the users delegate. This template function will store also additional parameters.
+ +
+ + Examle of usage:
+ + ---
+ + void handleTextEvent (Event e, int inset ) {
+ +     // ...
+ + }
+ + text.addListener (DWT.FocusOut, dgListener( &handleTextEvent, inset ));
+ + ---
+ +/
+Listener dgListener( Dg, T... )( Dg dg, T args ){
+    return new _DgListenerT!( Dg, T )( dg, args );
+}
+
+
+