The Tor Browser: layout/xul/nsStackLayout.cpp@7e26c7da4463

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 //

     7 // Eric Vaughan

     8 // Netscape Communications

     9 //

    10 // See documentation in associated header file

    11 //

    13 #include "nsStackLayout.h"

    14 #include "nsCOMPtr.h"

    15 #include "nsBoxLayoutState.h"

    16 #include "nsBox.h"

    17 #include "nsBoxFrame.h"

    18 #include "nsGkAtoms.h"

    19 #include "nsIContent.h"

    20 #include "nsNameSpaceManager.h"

    22 using namespace mozilla;

    24 nsBoxLayout* nsStackLayout::gInstance = nullptr;

    26 #define SPECIFIED_LEFT (1 << NS_SIDE_LEFT)

    27 #define SPECIFIED_RIGHT (1 << NS_SIDE_RIGHT)

    28 #define SPECIFIED_TOP (1 << NS_SIDE_TOP)

    29 #define SPECIFIED_BOTTOM (1 << NS_SIDE_BOTTOM)

    31 nsresult

    32 NS_NewStackLayout( nsIPresShell* aPresShell, nsCOMPtr<nsBoxLayout>& aNewLayout)

    33 {

    34   if (!nsStackLayout::gInstance) {

    35     nsStackLayout::gInstance = new nsStackLayout();

    36     NS_IF_ADDREF(nsStackLayout::gInstance);

    37   }

    38   // we have not instance variables so just return our static one.

    39   aNewLayout = nsStackLayout::gInstance;

    40   return NS_OK;

    41 }

    43 /*static*/ void

    44 nsStackLayout::Shutdown()

    45 {

    46   NS_IF_RELEASE(gInstance);

    47 }

    49 nsStackLayout::nsStackLayout()

    50 {

    51 }

    53 /*

    54  * Sizing: we are as wide as the widest child plus its left offset

    55  * we are tall as the tallest child plus its top offset.

    56  *

    57  * Only children which have -moz-stack-sizing set to stretch-to-fit

    58  * (the default) will be included in the size computations.

    59  */

    61 nsSize

    62 nsStackLayout::GetPrefSize(nsIFrame* aBox, nsBoxLayoutState& aState)

    63 {

    64   nsSize prefSize (0, 0);

    66   nsIFrame* child = aBox->GetChildBox();

    67   while (child) {

    68     if (child->StyleXUL()->mStretchStack) {

    69       nsSize pref = child->GetPrefSize(aState);

    71       AddMargin(child, pref);

    72       nsMargin offset;

    73       GetOffset(aState, child, offset);

    74       pref.width += offset.LeftRight();

    75       pref.height += offset.TopBottom();

    76       AddLargestSize(prefSize, pref);

    77     }

    79     child = child->GetNextBox();

    80   }

    82   AddBorderAndPadding(aBox, prefSize);

    84   return prefSize;

    85 }

    87 nsSize

    88 nsStackLayout::GetMinSize(nsIFrame* aBox, nsBoxLayoutState& aState)

    89 {

    90   nsSize minSize (0, 0);

    92   nsIFrame* child = aBox->GetChildBox();

    93   while (child) {

    94     if (child->StyleXUL()->mStretchStack) {

    95       nsSize min = child->GetMinSize(aState);

    97       AddMargin(child, min);

    98       nsMargin offset;

    99       GetOffset(aState, child, offset);

   100       min.width += offset.LeftRight();

   101       min.height += offset.TopBottom();

   102       AddLargestSize(minSize, min);

   103     }

   105     child = child->GetNextBox();

   106   }

   108   AddBorderAndPadding(aBox, minSize);

   110   return minSize;

   111 }

   113 nsSize

   114 nsStackLayout::GetMaxSize(nsIFrame* aBox, nsBoxLayoutState& aState)

   115 {

   116   nsSize maxSize (NS_INTRINSICSIZE, NS_INTRINSICSIZE);

   118   nsIFrame* child = aBox->GetChildBox();

   119   while (child) {

   120     if (child->StyleXUL()->mStretchStack) {

   121       nsSize min = child->GetMinSize(aState);

   122       nsSize max = child->GetMaxSize(aState);

   124       max = nsBox::BoundsCheckMinMax(min, max);

   126       AddMargin(child, max);

   127       nsMargin offset;

   128       GetOffset(aState, child, offset);

   129       max.width += offset.LeftRight();

   130       max.height += offset.TopBottom();

   131       AddSmallestSize(maxSize, max);

   132     }

   134     child = child->GetNextBox();

   135   }

   137   AddBorderAndPadding(aBox, maxSize);

   139   return maxSize;

   140 }

   143 nscoord

   144 nsStackLayout::GetAscent(nsIFrame* aBox, nsBoxLayoutState& aState)

   145 {

   146   nscoord vAscent = 0;

   148   nsIFrame* child = aBox->GetChildBox();

   149   while (child) {

   150     nscoord ascent = child->GetBoxAscent(aState);

   151     nsMargin margin;

   152     child->GetMargin(margin);

   153     ascent += margin.top;

   154     if (ascent > vAscent)

   155       vAscent = ascent;

   157     child = child->GetNextBox();

   158   }

   160   return vAscent;

   161 }

   163 uint8_t

   164 nsStackLayout::GetOffset(nsBoxLayoutState& aState, nsIFrame* aChild, nsMargin& aOffset)

   165 {

   166   aOffset = nsMargin(0, 0, 0, 0);

   168   // get the left, right, top and bottom offsets

   170   // As an optimization, we cache the fact that we are not positioned to avoid

   171   // wasting time fetching attributes.

   172   if (aChild->IsBoxFrame() &&

   173       (aChild->GetStateBits() & NS_STATE_STACK_NOT_POSITIONED))

   174     return 0;

   176   uint8_t offsetSpecified = 0;

   177   nsIContent* content = aChild->GetContent();

   178   if (content) {

   179     bool ltr = aChild->StyleVisibility()->mDirection == NS_STYLE_DIRECTION_LTR;

   180     nsAutoString value;

   181     nsresult error;

   183     content->GetAttr(kNameSpaceID_None, nsGkAtoms::start, value);

   184     if (!value.IsEmpty()) {

   185       value.Trim("%");

   186       if (ltr) {

   187         aOffset.left =

   188           nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   189         offsetSpecified |= SPECIFIED_LEFT;

   190       } else {

   191         aOffset.right =

   192           nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   193         offsetSpecified |= SPECIFIED_RIGHT;

   194       }

   195     }

   197     content->GetAttr(kNameSpaceID_None, nsGkAtoms::end, value);

   198     if (!value.IsEmpty()) {

   199       value.Trim("%");

   200       if (ltr) {

   201         aOffset.right =

   202           nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   203         offsetSpecified |= SPECIFIED_RIGHT;

   204       } else {

   205         aOffset.left =

   206           nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   207         offsetSpecified |= SPECIFIED_LEFT;

   208       }

   209     }

   211     content->GetAttr(kNameSpaceID_None, nsGkAtoms::left, value);

   212     if (!value.IsEmpty()) {

   213       value.Trim("%");

   214       aOffset.left =

   215         nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   216       offsetSpecified |= SPECIFIED_LEFT;

   217     }

   219     content->GetAttr(kNameSpaceID_None, nsGkAtoms::right, value);

   220     if (!value.IsEmpty()) {

   221       value.Trim("%");

   222       aOffset.right =

   223         nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   224       offsetSpecified |= SPECIFIED_RIGHT;

   225     }

   227     content->GetAttr(kNameSpaceID_None, nsGkAtoms::top, value);

   228     if (!value.IsEmpty()) {

   229       value.Trim("%");

   230       aOffset.top =

   231         nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   232       offsetSpecified |= SPECIFIED_TOP;

   233     }

   235     content->GetAttr(kNameSpaceID_None, nsGkAtoms::bottom, value);

   236     if (!value.IsEmpty()) {

   237       value.Trim("%");

   238       aOffset.bottom =

   239         nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));

   240       offsetSpecified |= SPECIFIED_BOTTOM;

   241     }

   242   }

   244   if (!offsetSpecified && aChild->IsBoxFrame()) {

   245     // If no offset was specified at all, then we cache this fact to avoid requerying

   246     // CSS or the content model.

   247     aChild->AddStateBits(NS_STATE_STACK_NOT_POSITIONED);

   248   }

   250   return offsetSpecified;

   251 }

   254 NS_IMETHODIMP

   255 nsStackLayout::Layout(nsIFrame* aBox, nsBoxLayoutState& aState)

   256 {

   257   nsRect clientRect;

   258   aBox->GetClientRect(clientRect);

   260   bool grow;

   262   do {

   263     nsIFrame* child = aBox->GetChildBox();

   264     grow = false;

   266     while (child)

   267     {

   268       nsMargin margin;

   269       child->GetMargin(margin);

   270       nsRect childRect(clientRect);

   271       childRect.Deflate(margin);

   273       if (childRect.width < 0)

   274         childRect.width = 0;

   276       if (childRect.height < 0)

   277         childRect.height = 0;

   279       nsRect oldRect(child->GetRect());

   280       bool sizeChanged = !oldRect.IsEqualEdges(childRect);

   282       // only lay out dirty children or children whose sizes have changed

   283       if (sizeChanged || NS_SUBTREE_DIRTY(child)) {

   284           // add in the child's margin

   285           nsMargin margin;

   286           child->GetMargin(margin);

   288           // obtain our offset from the top left border of the stack's content box.

   289           nsMargin offset;

   290           uint8_t offsetSpecified = GetOffset(aState, child, offset);

   292           // Set the position and size based on which offsets have been specified:

   293           //   left only - offset from left edge, preferred width

   294           //   right only - offset from right edge, preferred width

   295           //   left and right - offset from left and right edges, width in between this

   296           //   neither - no offset, full width of stack

   297           // Vertical direction is similar.

   298           //

   299           // Margins on the child are also included in the edge offsets

   300           if (offsetSpecified) {

   301             if (offsetSpecified & SPECIFIED_LEFT) {

   302               childRect.x = clientRect.x + offset.left + margin.left;

   303               if (offsetSpecified & SPECIFIED_RIGHT) {

   304                 nsSize min = child->GetMinSize(aState);

   305                 nsSize max = child->GetMaxSize(aState);

   306                 nscoord width = clientRect.width - offset.LeftRight() - margin.LeftRight();

   307                 childRect.width = clamped(width, min.width, max.width);

   308               }

   309               else {

   310                 childRect.width = child->GetPrefSize(aState).width;

   311               }

   312             }

   313             else if (offsetSpecified & SPECIFIED_RIGHT) {

   314               childRect.width = child->GetPrefSize(aState).width;

   315               childRect.x = clientRect.XMost() - offset.right - margin.right - childRect.width;

   316             }

   318             if (offsetSpecified & SPECIFIED_TOP) {

   319               childRect.y = clientRect.y + offset.top + margin.top;

   320               if (offsetSpecified & SPECIFIED_BOTTOM) {

   321                 nsSize min = child->GetMinSize(aState);

   322                 nsSize max = child->GetMaxSize(aState);

   323                 nscoord height = clientRect.height - offset.TopBottom() - margin.TopBottom();

   324                 childRect.height = clamped(height, min.height, max.height);

   325               }

   326               else {

   327                 childRect.height = child->GetPrefSize(aState).height;

   328               }

   329             }

   330             else if (offsetSpecified & SPECIFIED_BOTTOM) {

   331               childRect.height = child->GetPrefSize(aState).height;

   332               childRect.y = clientRect.YMost() - offset.bottom - margin.bottom - childRect.height;

   333             }

   334           }

   336           // Now place the child.

   337           child->SetBounds(aState, childRect);

   339           // Flow the child.

   340           child->Layout(aState);

   342           // Get the child's new rect.

   343           childRect = child->GetRect();

   344           childRect.Inflate(margin);

   346           if (child->StyleXUL()->mStretchStack) {

   347             // Did the child push back on us and get bigger?

   348             if (offset.LeftRight() + childRect.width > clientRect.width) {

   349               clientRect.width = childRect.width + offset.LeftRight();

   350               grow = true;

   351             }

   353             if (offset.TopBottom() + childRect.height > clientRect.height) {

   354               clientRect.height = childRect.height + offset.TopBottom();

   355               grow = true;

   356             }

   357           }

   358        }

   360        child = child->GetNextBox();

   361      }

   362    } while (grow);

   364    // if some HTML inside us got bigger we need to force ourselves to

   365    // get bigger

   366    nsRect bounds(aBox->GetRect());

   367    nsMargin bp;

   368    aBox->GetBorderAndPadding(bp);

   369    clientRect.Inflate(bp);

   371    if (clientRect.width > bounds.width || clientRect.height > bounds.height)

   372    {

   373      if (clientRect.width > bounds.width)

   374        bounds.width = clientRect.width;

   375      if (clientRect.height > bounds.height)

   376        bounds.height = clientRect.height;

   378      aBox->SetBounds(aState, bounds);

   379    }

   381    return NS_OK;

   382 }

The Tor Browser / file revision

layout/xul/nsStackLayout.cpp@7e26c7da4463

layout/xul/nsStackLayout.cpp