Bug1300: make Ctrl+V work in text field of Save dialog, but...

It's a bit crude.  It always pastes the entire text field, ignoring the
insertion cursor, and ignoring which control really has the focus.

The file dialog, which can call up the Finder, is implemented in the AppKit
so it's not wholly under our control.  But I could bolt on an event filter,
after the fashion of CommandManager, to intercept key events.

Perhaps later versions of the toolkit than 10.6 will have a better save dialog
in the AppKit, making this change unnecessary.

lib-src/FileDialog/mac/FileDialogPrivate.mm

@@ -32,6 +32,7 @@
     #include "wx/choice.h"
 #endif
 
+#include "wx/clipbrd.h"
 #include "wx/filename.h"
 #include "wx/tokenzr.h"
 #include "wx/evtloop.h"
@@ -607,6 +608,45 @@ int FileDialog::ShowModal()
 
         SetupExtraControls(sPanel);
 
+        // PRL:
+        // Hack for bug 1300:  intercept key down events, implement a
+        // Command+V handler, but it's a bit crude.  It always pastes
+        // the entire text field, ignoring the insertion cursor, and ignoring
+        // which control really has the focus.
+        id handler;
+        if (wxTheClipboard->IsSupported(wxDF_TEXT)) {
+           handler = [
+              NSEvent addLocalMonitorForEventsMatchingMask:NSKeyDownMask
+              handler:^NSEvent *(NSEvent *event)
+              {
+                 if ([event modifierFlags] & NSCommandKeyMask)
+                 {
+                    auto chars = [event charactersIgnoringModifiers];
+                    auto character = [chars characterAtIndex:0];
+                    if (character == 'v')
+                    {
+                       if (wxTheClipboard->Open()) {
+                          wxTextDataObject data;
+                          wxTheClipboard->GetData(data);
+                          wxTheClipboard->Close();
+                          wxString text = data.GetText();
+                          NSString *myString = [[NSString alloc]
+                             initWithCharacters:
+                                (unsigned short*)text.c_str().AsWChar()
+                             length:text.Length()
+                          ];
+                          [sPanel setNameFieldStringValue:myString];
+                          [myString release];
+                          return nil;
+                       }
+                    }
+                 }
+
+                 return event;
+              }
+           ];
+        }
+
         // makes things more convenient:
         [sPanel setCanCreateDirectories:YES];
         [sPanel setMessage:cf.AsNSString()];
@@ -636,6 +676,9 @@ int FileDialog::ShowModal()
 
         returnCode = [sPanel runModalForDirectory: m_dir.IsEmpty() ? nil : dir.AsNSString() file:file.AsNSString() ];
         ModalFinishedCallback(sPanel, returnCode);
+
+        if (wxTheClipboard->IsSupported(wxDF_TEXT))
+           [NSEvent removeMonitor:handler];
     }
     else
     {