macOS clientRect implementation for non-primary displays

src/osx/cocoa/utils.mm

@@ -485,6 +485,24 @@ wxRect wxOSXGetMainDisplayClientArea()
     return wxFromNSRect( NULL, displayRect );
 }
 
+static NSScreen* wxOSXGetScreenFromDisplay( CGDirectDisplayID ID)
+{
+    for (NSScreen* screen in [NSScreen screens])
+    {
+        CGDirectDisplayID displayID = [[[screen deviceDescription] objectForKey:@"NSScreenNumber"] intValue];
+        if ( displayID == ID )
+            return screen;
+    }
+    return NULL;
+}
+
+extern // used from src/osx/core/display.cpp
+wxRect wxOSXGetDisplayClientArea(CGDirectDisplayID ID)
+{
+    NSRect displayRect = [wxOSXGetScreenFromDisplay(ID) visibleFrame];
+    return wxFromNSRect( NULL, displayRect );
+}
+
 void wxGetMousePosition( int* x, int* y )
 {
     wxPoint pt = wxFromNSPoint(NULL, [NSEvent mouseLocation]);

src/osx/core/display.cpp

@@ -40,6 +40,7 @@
 
 // This one is defined in Objective C++ code.
 extern wxRect wxOSXGetMainDisplayClientArea();
+extern wxRect wxOSXGetDisplayClientArea(CGDirectDisplayID id);
 
 namespace
 {
@@ -297,13 +298,7 @@ wxRect wxDisplayImplMacOSX::GetGeometry() const
 
 wxRect wxDisplayImplMacOSX::GetClientArea() const
 {
-    // VZ: I don't know how to get client area for arbitrary display but
-    //     wxGetClientDisplayRect() does work correctly for at least the main
-    //     one (TODO: do it correctly for the other displays too)
-    if ( IsPrimary() )
-        return wxOSXGetMainDisplayClientArea();
-
-    return wxDisplayImpl::GetClientArea();
+    return wxOSXGetDisplayClientArea(m_id);
 }
 
 int wxDisplayImplMacOSX::GetDepth() const