UI: Multi-cast Delegate

ui/h3r_button.cpp

@@ -189,7 +189,7 @@ void Button::OnMouseUp(const EventArgs &)
     // there shall be no mouse click event.
     if (! _mouse_over) return;
     Log::Info ("MouseUp" EOL);
-    if (OnClick) OnClick (this);
+    OnClick (nullptr);
 }
 
 // void Button::OnRender(GC &) {}

ui/h3r_button.h

@@ -42,6 +42,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "h3r_control.h"
 #include "h3r_eventargs.h"
 #include "h3r_renderengine.h"
+#include "h3r_event.h"
 
 H3R_NAMESPACE
 
@@ -74,9 +75,8 @@ class Button: public Control
     private: bool _mouse_over {};
     private: bool _mouse_down {};
 
-    // Experiment: you attach here a capturing lambda via a template function
-    // pointer: EventDelegate<decltype(cl)>
-    public: void (*OnClick)(Control * sender) {};
+    // Usage: OnClick.Subscribe (this, &descendant_of_IHandleEvents::handler)
+    public: Event OnClick {};
 };
 
 NAMESPACE_H3R

ui/h3r_control.cpp

@@ -84,10 +84,10 @@ Control * Control::SetPos(int x, int y)
 
 bool Control::HitTest(Point & p) { return _bb.Contains (p); }
 
-void Control::OnEvent(Event & e)
+/*void Control::OnEvent(Event & e)
 {
     EventArgs foo;
     e.Do (*this, foo);
-}
+}*/
 
 NAMESPACE_H3R

ui/h3r_control.h

@@ -123,7 +123,8 @@ class Control
 
     //TODO hint system; MyHint: Event ... show_hint (myhint);
     //     Control.RMB += (Event & ShowHint) => Root().OnEvent (ShowHint);
-    public: virtual void OnEvent(Event &);
+    //     After merging CoR back into the mcast delegate.
+    // public: virtual void OnEvent(Event &);
 };
 
 NAMESPACE_H3R

ui/h3r_event.h

@@ -38,11 +38,62 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #define _H3R_EVENT_H_
 
 #include "h3r.h"
+#include "h3r_list.h"
+#include "h3r_log.h"
 
 H3R_NAMESPACE
 #define public public:
 #define private private:
 
+struct EventArgs;
+
+// You implement this at the class that shall handle events.
+struct IHandleEvents {};
+
+namespace {
+
+using EventHandler = void (IHandleEvents::*)(EventArgs * args);
+// Binder. UI only, so thread-unsafe.
+template <typename Obj> class McastD final
+{
+    public using EventHandler = void (Obj::*)(EventArgs * args);
+    private struct Delegate final
+    {
+        Delegate(EventHandler eh, Obj * object)
+            : EH{eh}, Object{object} {}
+        ~Delegate() { Object = {}; EH = {}; }
+        EventHandler EH;
+        Obj * Object;
+        bool operator==(const Delegate & b) const
+        {
+            return EH == b.EH && Object == b.Object;
+        }
+    };
+    private List<Delegate> _subscribers {};
+    public McastD() {}
+    public ~McastD() { for (auto & d : _subscribers) d.~Delegate (); }
+    public template <typename T> McastD & Subscribe(Obj * obj, T eh)
+    {
+        Delegate d {static_cast<EventHandler>(eh), obj};
+        if (! _subscribers.Contains (d))
+            _subscribers.Add (d);
+        else
+            Log::Info ("Warning: subscribing twice isn't supported" EOL);
+        return *this;
+    }
+    public void operator()(EventArgs * args)
+    {
+        for (auto & d : _subscribers)
+            if (d.Object && d.EH) (d.Object->*d.EH) (args);
+    }
+};// Multi-cast Delegate
+}
+
+// Use this at the event providers: Event OnFoo; notify: OnFoo ();
+using Event = McastD<IHandleEvents>;
+
+//LATER merge this, above.
+//
 // class ShowProgress : public Event
 // {
 //     void Do(class Control * c) override
@@ -58,7 +109,7 @@ H3R_NAMESPACE
 // the one who sent the event. For non-UI events that shall be null obviously.
 // I hope this won't become a showstopper at some point, since I'm combining
 // one too many responsibilities in this single class.
-class Event
+/*class Event
 {
     // Do you know how hard is to turn this into a multi-cast delegate?
     // Not at all.
@@ -77,7 +128,7 @@ class Event
     public inline virtual bool Handled() { return true; }
     // Why is this "virtual" eludes me still. Perhaps on the next re-read.
     public inline virtual void SetNext(Event * next_eh) { _next = next_eh; }
-};
+};*/
 
 // The book responsible for code like the above one:
 // "Design Patterns: Elements of Reusable Object-Oriented Software"

ui/h3r_mainwindow.cpp

@@ -94,14 +94,7 @@ MainWindow::MainWindow(OSWindow * actual_window, Point && size)
         y += btn->Size ().Y + spacing;
         btn_quit = btn;
     }
-    btn_quit->OnClick = [](Control *) {
-        // The mesage is located at GENRLTXT.TXT:81 (1-based)
-        auto dr = MessageBox::Show ("Are you sure you want to quit?",
-            "MedFont.fnt", MessageBox::Buttons::OKCancel);
-        if (DialogResult::OK == dr)
-            ;
-        //TODO check if all message boxes are using this font
-    };
+    btn_quit->OnClick.Subscribe (this, &MainWindow::Quit);
     // 2. Layout
     for (Control * btn : Controls ())
         btn->SetPos (
@@ -167,4 +160,14 @@ void MainWindow::OnResize(int w, int h)
     SetSize (Point {w, h});
 }
 
+void MainWindow::Quit(EventArgs *)
+{
+    // The mesage is located at GENRLTXT.TXT:81 (1-based)
+    auto dr = MessageBox::Show ("Are you sure you want to quit?",
+    //TODO check if all message boxes are using this font
+        "MedFont.fnt", MessageBox::Buttons::OKCancel);
+    if (DialogResult::OK == dr)
+        Close ();
+}
+
 NAMESPACE_H3R

ui/h3r_mainwindow.h

@@ -38,11 +38,12 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "h3r.h"
 #include "h3r_window.h"
 #include "h3r_label.h"
+#include "h3r_event.h"
 
 H3R_NAMESPACE
 
 // MainWindow
-class MainWindow final : public Window
+class MainWindow final : public Window, public IHandleEvents
 {
 #define public public:
 #define private private:
@@ -53,10 +54,12 @@ class MainWindow final : public Window
     public MainWindow(OSWindow *, Point &&);
     public ~MainWindow() override;
 
-    protected void OnKeyUp(const EventArgs &) override;
-    protected void OnShow() override;
-    protected void OnRender() override;
-    protected void OnResize(int w, int h) override;
+    private void OnKeyUp(const EventArgs &) override;
+    private void OnShow() override;
+    private void OnRender() override;
+    private void OnResize(int w, int h) override;
+
+    private void Quit(EventArgs *);
 };
 
 #undef public

ui/h3r_messagebox.cpp

@@ -217,9 +217,11 @@ MessageBox::MessageBox(Window * base_window, Point && size,
     H3R_CREATE_OBJECT(btn_ok, Button) {"iOKAY.def", this};
     btn_ok->SetPos (327, 335);
     btn_ok->UploadFrames ();
+    btn_ok->OnClick.Subscribe (this, &MessageBox::HandleOKClick);
     H3R_CREATE_OBJECT(btn_cancel, Button) {"iCANCEL.def", this};
     btn_cancel->SetPos (410, 335);
     btn_cancel->UploadFrames ();
+    btn_cancel->OnClick.Subscribe (this, &MessageBox::HandleCancelClick);
 }
 
 /*static*/ DialogResult MessageBox::Show(
@@ -273,4 +275,16 @@ void MessageBox::OnKeyUp(const EventArgs & e)
     }
 }
 
+void MessageBox::HandleOKClick(EventArgs *)
+{
+    printf ("OK clicked" EOL);
+    _dr = DialogResult::OK; _has_dr = true;
+}
+
+void MessageBox::HandleCancelClick(EventArgs *)
+{
+    printf ("Cancel clicked" EOL);
+    _dr = DialogResult::Cancel; _has_dr = true;
+}
+
 NAMESPACE_H3R

ui/h3r_messagebox.h

@@ -40,6 +40,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "h3r_dialogwindow.h"
 #include "h3r_string.h"
 #include "h3r_list.h"
+#include "h3r_event.h"
 
 H3R_NAMESPACE
 
@@ -79,7 +80,7 @@ H3R_NAMESPACE
 //TODO generate the per color "dialgbox.def" on the fly; check if the unknown
 //     bytes doesn't hint something about a color mixer
 //
-class MessageBox final : public DialogWindow
+class MessageBox final : public DialogWindow, public IHandleEvents
 {
 #define public public:
 #define private private:
@@ -101,6 +102,9 @@ class MessageBox final : public DialogWindow
 
     public DialogResult ShowDialog();
     protected void OnKeyUp(const EventArgs &) override;
+
+    private void HandleOKClick(EventArgs *);
+    private void HandleCancelClick(EventArgs *);
 };
 
 #undef public