Mac: Fix window ordering for certificate viewer/selector sheets and overlays.

chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.h"
 
 #import <SecurityInterface/SFChooseIdentityPanel.h>
 #include <stddef.h>
 
 #include <utility>
@@ skipping 268 matching lines @@
   [panel_ _dismissWithCode:NSFileHandlingPanelCancelButton];
 }
 
 - (void)hideSheet {
   NSWindow* sheetWindow = [overlayWindow_ attachedSheet];
   [sheetWindow setAlphaValue:0.0];
   [sheetWindow setIgnoresMouseEvents:YES];
 
   oldResizesSubviews_ = [[sheetWindow contentView] autoresizesSubviews];
   [[sheetWindow contentView] setAutoresizesSubviews:NO];
+
+  // Ensure this overlay doesn't interfere with overlays with hidden sheets.
+  [overlayWindow_ setLevel:0];

[tapted, 2016/12/09 04:02:00]

We should be passing an NSFooWindowLevel to setLevel. E.g. NSNormalWindowLevel,
NSFloatingWindowLevel, etc. There's a `CGWindowLevel.h` which uses the same
constants -- I don't know whether 0/1 will do the right thing  (NSFooWindowLevel
is actually a macro that results in a function call returning some unknown
integer). But! I don't think setLevel is right.

Can we use NSWindow's

- (void)orderWindow:(NSWindowOrderingMode)place 
         relativeTo:(NSInteger)otherWin;

instead?

[Patti Lor, 2016/12/09 05:02:49]

Yeah, I considered this. It adds some complexity because the child windows will
need to be retrieved via the parent window, and there always seems to be 1
mysterious child window (the count is always # of overlay windows + 1). I don't
think it works either, I tried just looping through |overlayWindow_|'s parent's
child windows (excluding overlayWindow_) and calling orderWindow:relativeTo: on
them (passing in [child {level,orderedLevel,windowNumber}], not sure which is
the right one), and it still has the buggy behaviour.

 }
 
 - (void)unhideSheet {
   NSWindow* sheetWindow = [overlayWindow_ attachedSheet];
   [[sheetWindow contentView] setAutoresizesSubviews:oldResizesSubviews_];
   [sheetWindow setAlphaValue:1.0];
   [sheetWindow setIgnoresMouseEvents:NO];
+
+  // Set the current overlay's level higher than overlays with hidden sheets.
+  [overlayWindow_ setLevel:1];
 }
 
 - (void)pulseSheet {
   // NOOP
 }
 
 - (void)makeSheetKeyAndOrderFront {
   [[overlayWindow_ attachedSheet] makeKeyAndOrderFront:nil];
 }
 
@@ skipping 10 matching lines @@
 }
 
 - (void)onConstrainedWindowClosed {
   observer_->StopObserving();
   panel_.reset();
   constrainedWindow_.reset();
   [self release];
 }
 
 @end