Bugfix: EmbedExternalExampleUI resizing on Mac (#319)

* Bugfix: EmbedExternalExampleUI resizing on Mac

* Make 6618e99 follow existing ObjC code style

Also allow uiIdle() to run for X11

examples/EmbedExternalUI/EmbedExternalExampleUI.cpp

@@ -96,11 +96,10 @@ public:
         fView = [NSView new];
         DISTRHO_SAFE_ASSERT_RETURN(fView != nullptr,);
 
-        [fView initWithFrame:NSMakeRect(0, 0, getWidth(), getHeight())];
-        [fView setAutoresizesSubviews:YES];
         [fView setFrame:NSMakeRect(0, 0, getWidth(), getHeight())];
-        [fView setHidden:NO];
-        [fView setNeedsDisplay:YES];
+        [fView setAutoresizesSubviews:YES];
+        [fView setWantsLayer:YES];
+        [[fView layer] setBackgroundColor:[[NSColor blueColor] CGColor]];
 
         if (isEmbed())
         {
@@ -271,6 +270,9 @@ protected:
         UI::sizeChanged(width, height);
 
 #if defined(DISTRHO_OS_MAC)
+        NSRect rect = [fView frame];
+        rect.size = CGSizeMake((CGFloat)width, (CGFloat)height);
+        [fView setFrame:rect];
 #elif defined(DISTRHO_OS_WINDOWS)
 #else
         if (fWindow != 0)
@@ -343,6 +345,10 @@ protected:
     {
         // d_stdout("uiIdle");
 #if defined(DISTRHO_OS_MAC)
+        if (isEmbed()) {
+            return;
+        }
+
         NSAutoreleasePool* const pool = [[NSAutoreleasePool alloc] init];
         NSDate* const date = [NSDate distantPast];