1 files changed, 118 insertions, 0 deletions
diff --git a/wx+/key_event.h b/wx+/key_event.h
new file mode 100644
index 00000000..60cb7372
--- /dev/null
+++ b/wx+/key_event.h
@@ -0,0 +1,118 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved        *
+// **************************************************************************
+
+#ifndef KEY_EVENT_H_086130871086708354674
+#define KEY_EVENT_H_086130871086708354674
+
+#include <functional>
+#include <zen/scope_guard.h>
+#include <wx/toplevel.h>
+#include <wx/window.h>
+#include <wx/event.h>
+
+namespace zen
+{
+//wxWidgets provides no elegant way to register shortcut keys scoped for dialog windows =>
+//enable dialog-specific local key events!
+
+//setup in wxDialog-derived class' constructor, e.g.:
+//	setupLocalKeyEvents(*this, [this](wxKeyEvent& event){ this->onLocalKeyEvent(event); });
+//
+// => redirects local key events to:
+//	void MyDlg::onLocalKeyEvent(wxKeyEvent& event);
+void setupLocalKeyEvents(wxWindow& wnd, const std::function<void(wxKeyEvent& event)>& callback); //callback held during life time of "wnd"!
+
+
+
+
+
+
+
+//pretty much the same like "bool wxWindowBase::IsDescendant(wxWindowBase* child) const" but without the obvious misnaming
+inline
+bool isComponentOf(const wxWindow* child, const wxWindow* top)
+{
+    for (const wxWindow* wnd = child; wnd != nullptr; wnd = wnd->GetParent())
+        if (wnd == top)
+            return true;
+    return false;
+}
+
+
+namespace impl
+{
+inline
+const wxTopLevelWindow* getTopLevelWindow(const wxWindow* child)
+{
+    for (const wxWindow* wnd = child; wnd != nullptr; wnd = wnd->GetParent())
+        if (auto tlw = dynamic_cast<const wxTopLevelWindow*>(wnd))
+            return tlw;
+    return nullptr;
+}
+
+
+class LokalKeyEventHandler : public wxWindow //private wxEvtHandler
+{
+public:
+    LokalKeyEventHandler(wxWindow& parent, const std::function<void(wxKeyEvent& event)>& callback) : wxWindow(&parent, wxID_ANY), //use a dummy child window to bind instance life time to parent
+        parent_(parent),
+        callback_(callback),
+        processingCallback(false)
+    {
+		    Hide();    //this is just a dummy window so that its parent can have ownership
+            Disable(); //
+
+        //register global hotkeys (without needing explicit menu entry)
+        wxTheApp->Connect(wxEVT_KEY_DOWN,  wxKeyEventHandler(LokalKeyEventHandler::onGlobalKeyEvent), nullptr, this);
+        wxTheApp->Connect(wxEVT_CHAR_HOOK, wxKeyEventHandler(LokalKeyEventHandler::onGlobalKeyEvent), nullptr, this); //capture direction keys
+    }
+
+    ~LokalKeyEventHandler()
+    {
+        //important! event source wxTheApp lives longer than this instance -> disconnect!
+        wxTheApp->Disconnect(wxEVT_KEY_DOWN,  wxKeyEventHandler(LokalKeyEventHandler::onGlobalKeyEvent), nullptr, this);
+        wxTheApp->Disconnect(wxEVT_CHAR_HOOK, wxKeyEventHandler(LokalKeyEventHandler::onGlobalKeyEvent), nullptr, this);
+    }
+
+private:
+    void onGlobalKeyEvent(wxKeyEvent& event)
+    {
+        const wxWindow* focus = wxWindow::FindFocus();
+        const wxTopLevelWindow* tlw = getTopLevelWindow(&parent_);
+
+        //avoid recursion!!! -> this ugly construct seems to be the only (portable) way to avoid re-entrancy
+        //recursion may happen in multiple situations: e.g. modal dialogs, Grid::ProcessEvent()!
+        if (processingCallback ||
+            !isComponentOf(focus, &parent_) ||
+            !parent_.IsEnabled() || //only handle if window is in use and no modal dialog is shown:
+            !tlw || !const_cast<wxTopLevelWindow*>(tlw)->IsActive())    //thanks to wxWidgets non-portability we need both checks:
+            //IsEnabled() is sufficient for Windows, IsActive() is needed on OS X since it does NOT disable the parent when showing a modal dialog
+        {
+            event.Skip();
+            return;
+        }
+        processingCallback = true;
+        ZEN_ON_SCOPE_EXIT(processingCallback = false;)
+
+        callback_(event);
+    }
+
+    wxWindow& parent_;
+    const std::function<void(wxKeyEvent& event)> callback_;
+    bool processingCallback;
+};
+}
+
+
+inline
+void setupLocalKeyEvents(wxWindow& wnd, const std::function<void(wxKeyEvent& event)>& callback)
+{
+    new impl::LokalKeyEventHandler(wnd, callback); //ownership passed to "wnd"!
+}
+
+}
+
+#endif //KEY_EVENT_H_086130871086708354674