1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4  * License, v. 2.0. If a copy of the MPL was not distributed with this
5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 
7 //
8 // Eric Vaughan
9 // Netscape Communications
10 //
11 // See documentation in associated header file
12 //
13 
14 #include "mozilla/PresShell.h"
15 #include "nsGridRowGroupFrame.h"
16 #include "nsGridRowLeafLayout.h"
17 #include "nsGridRow.h"
18 #include "nsBoxLayoutState.h"
19 #include "nsGridLayout2.h"
20 
21 using namespace mozilla;
22 
23 already_AddRefed<nsBoxLayout> NS_NewGridRowGroupLayout();
24 
NS_NewGridRowGroupFrame(PresShell * aPresShell,ComputedStyle * aStyle)25 nsIFrame* NS_NewGridRowGroupFrame(PresShell* aPresShell,
26                                   ComputedStyle* aStyle) {
27   nsCOMPtr<nsBoxLayout> layout = NS_NewGridRowGroupLayout();
28   return new (aPresShell)
29       nsGridRowGroupFrame(aStyle, aPresShell->GetPresContext(), layout);
30 }
31 
NS_IMPL_FRAMEARENA_HELPERS(nsGridRowGroupFrame)32 NS_IMPL_FRAMEARENA_HELPERS(nsGridRowGroupFrame)
33 
34 /**
35  * This is redefined because row groups have a funny property. If they are
36  * flexible then their flex must be equal to the sum of their children's flexes.
37  */
38 nscoord nsGridRowGroupFrame::GetXULFlex() {
39   // if we are flexible out flexibility is determined by our columns.
40   // so first get the our flex. If not 0 then our flex is the sum of
41   // our columns flexes.
42 
43   if (!XULNeedsRecalc(mFlex)) {
44     return mFlex;
45   }
46 
47   if (nsBoxFrame::GetXULFlex() == 0) {
48     return 0;
49   }
50 
51   // ok we are flexible add up our children
52   nscoord totalFlex = 0;
53   nsIFrame* child = nsIFrame::GetChildXULBox(this);
54   while (child) {
55     totalFlex += child->GetXULFlex();
56     child = GetNextXULBox(child);
57   }
58 
59   mFlex = totalFlex;
60 
61   return totalFlex;
62 }
63