summaryrefslogtreecommitdiff
path: root/layout/xul/nsStackLayout.cpp
blob: 6072e0612b801e355fe2b03047be7e5cb3e25759 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

//
// Eric Vaughan
// Netscape Communications
//
// See documentation in associated header file
//

#include "nsStackLayout.h"
#include "nsCOMPtr.h"
#include "nsBoxLayoutState.h"
#include "nsBox.h"
#include "nsBoxFrame.h"
#include "nsGkAtoms.h"
#include "nsIContent.h"
#include "nsNameSpaceManager.h"

using namespace mozilla;

nsBoxLayout* nsStackLayout::gInstance = nullptr;

#define SPECIFIED_LEFT (1 << NS_SIDE_LEFT)
#define SPECIFIED_RIGHT (1 << NS_SIDE_RIGHT)
#define SPECIFIED_TOP (1 << NS_SIDE_TOP)
#define SPECIFIED_BOTTOM (1 << NS_SIDE_BOTTOM)

nsresult
NS_NewStackLayout(nsCOMPtr<nsBoxLayout>& aNewLayout)
{
  if (!nsStackLayout::gInstance) {
    nsStackLayout::gInstance = new nsStackLayout();
    NS_IF_ADDREF(nsStackLayout::gInstance);
  }
  // we have not instance variables so just return our static one.
  aNewLayout = nsStackLayout::gInstance;
  return NS_OK;
} 

/*static*/ void
nsStackLayout::Shutdown()
{
  NS_IF_RELEASE(gInstance);
}

nsStackLayout::nsStackLayout()
{
}

/*
 * Sizing: we are as wide as the widest child plus its left offset
 * we are tall as the tallest child plus its top offset.
 *
 * Only children which have -moz-stack-sizing set to stretch-to-fit
 * (the default) will be included in the size computations.
 */

nsSize
nsStackLayout::GetXULPrefSize(nsIFrame* aBox, nsBoxLayoutState& aState)
{
  nsSize prefSize (0, 0);

  nsIFrame* child = nsBox::GetChildXULBox(aBox);
  while (child) {
    if (child->StyleXUL()->mStretchStack) {
      nsSize pref = child->GetXULPrefSize(aState);

      AddMargin(child, pref);
      nsMargin offset;
      GetOffset(child, offset);
      pref.width += offset.LeftRight();
      pref.height += offset.TopBottom();
      AddLargestSize(prefSize, pref);
    }

    child = nsBox::GetNextXULBox(child);
  }

  AddBorderAndPadding(aBox, prefSize);

  return prefSize;
}

nsSize
nsStackLayout::GetXULMinSize(nsIFrame* aBox, nsBoxLayoutState& aState)
{
  nsSize minSize (0, 0);

  nsIFrame* child = nsBox::GetChildXULBox(aBox);
  while (child) {
    if (child->StyleXUL()->mStretchStack) {
      nsSize min = child->GetXULMinSize(aState);

      AddMargin(child, min);
      nsMargin offset;
      GetOffset(child, offset);
      min.width += offset.LeftRight();
      min.height += offset.TopBottom();
      AddLargestSize(minSize, min);
    }

    child = nsBox::GetNextXULBox(child);
  }

  AddBorderAndPadding(aBox, minSize);

  return minSize;
}

nsSize
nsStackLayout::GetXULMaxSize(nsIFrame* aBox, nsBoxLayoutState& aState)
{
  nsSize maxSize (NS_INTRINSICSIZE, NS_INTRINSICSIZE);

  nsIFrame* child = nsBox::GetChildXULBox(aBox);
  while (child) {
    if (child->StyleXUL()->mStretchStack) {
      nsSize min = child->GetXULMinSize(aState);
      nsSize max = child->GetXULMaxSize(aState);

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

      AddMargin(child, max);
      nsMargin offset;
      GetOffset(child, offset);
      max.width += offset.LeftRight();
      max.height += offset.TopBottom();
      AddSmallestSize(maxSize, max);
    }

    child = nsBox::GetNextXULBox(child);
  }

  AddBorderAndPadding(aBox, maxSize);

  return maxSize;
}


nscoord
nsStackLayout::GetAscent(nsIFrame* aBox, nsBoxLayoutState& aState)
{
  nscoord vAscent = 0;

  nsIFrame* child = nsBox::GetChildXULBox(aBox);
  while (child) {  
    nscoord ascent = child->GetXULBoxAscent(aState);
    nsMargin margin;
    child->GetXULMargin(margin);
    ascent += margin.top;
    if (ascent > vAscent)
      vAscent = ascent;

    child = nsBox::GetNextXULBox(child);
  }

  return vAscent;
}

uint8_t
nsStackLayout::GetOffset(nsIFrame* aChild, nsMargin& aOffset)
{
  aOffset = nsMargin(0, 0, 0, 0);

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

  // As an optimization, we cache the fact that we are not positioned to avoid
  // wasting time fetching attributes.
  if (aChild->IsXULBoxFrame() &&
      (aChild->GetStateBits() & NS_STATE_STACK_NOT_POSITIONED))
    return 0;

  uint8_t offsetSpecified = 0;
  nsIContent* content = aChild->GetContent();
  if (content) {
    bool ltr = aChild->StyleVisibility()->mDirection == NS_STYLE_DIRECTION_LTR;
    nsAutoString value;
    nsresult error;

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::start, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      if (ltr) {
        aOffset.left =
          nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
        offsetSpecified |= SPECIFIED_LEFT;
      } else {
        aOffset.right =
          nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
        offsetSpecified |= SPECIFIED_RIGHT;
      }
    }

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::end, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      if (ltr) {
        aOffset.right =
          nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
        offsetSpecified |= SPECIFIED_RIGHT;
      } else {
        aOffset.left =
          nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
        offsetSpecified |= SPECIFIED_LEFT;
      }
    }

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::left, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      aOffset.left =
        nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
      offsetSpecified |= SPECIFIED_LEFT;
    }

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::right, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      aOffset.right =
        nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
      offsetSpecified |= SPECIFIED_RIGHT;
    }

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::top, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      aOffset.top =
        nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
      offsetSpecified |= SPECIFIED_TOP;
    }

    content->GetAttr(kNameSpaceID_None, nsGkAtoms::bottom, value);
    if (!value.IsEmpty()) {
      value.Trim("%");
      aOffset.bottom =
        nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
      offsetSpecified |= SPECIFIED_BOTTOM;
    }
  }

  if (!offsetSpecified && aChild->IsXULBoxFrame()) {
    // If no offset was specified at all, then we cache this fact to avoid requerying
    // CSS or the content model.
    aChild->AddStateBits(NS_STATE_STACK_NOT_POSITIONED);
  }

  return offsetSpecified;
}


NS_IMETHODIMP
nsStackLayout::XULLayout(nsIFrame* aBox, nsBoxLayoutState& aState)
{
  nsRect clientRect;
  aBox->GetXULClientRect(clientRect);

  bool grow;

  do {
    nsIFrame* child = nsBox::GetChildXULBox(aBox);
    grow = false;

    while (child) 
    {  
      nsMargin margin;
      child->GetXULMargin(margin);
      nsRect childRect(clientRect);
      childRect.Deflate(margin);

      if (childRect.width < 0)
        childRect.width = 0;

      if (childRect.height < 0)
        childRect.height = 0;

      nsRect oldRect(child->GetRect());
      bool sizeChanged = !oldRect.IsEqualEdges(childRect);

      // only lay out dirty children or children whose sizes have changed
      if (sizeChanged || NS_SUBTREE_DIRTY(child)) {
          // add in the child's margin
          nsMargin margin;
          child->GetXULMargin(margin);

          // obtain our offset from the top left border of the stack's content box.
          nsMargin offset;
          uint8_t offsetSpecified = GetOffset(child, offset);

          // Set the position and size based on which offsets have been specified:
          //   left only - offset from left edge, preferred width
          //   right only - offset from right edge, preferred width
          //   left and right - offset from left and right edges, width in between this
          //   neither - no offset, full width of stack
          // Vertical direction is similar.
          //
          // Margins on the child are also included in the edge offsets
          if (offsetSpecified) {
            nsSize min = child->GetXULMinSize(aState);
            nsSize max = child->GetXULMaxSize(aState);
            if (offsetSpecified & SPECIFIED_LEFT) {
              childRect.x = clientRect.x + offset.left + margin.left;
              if (offsetSpecified & SPECIFIED_RIGHT) {
                nscoord width = clientRect.width - offset.LeftRight() - margin.LeftRight();
                childRect.width = clamped(width, min.width, max.width);
              }
              else {
                nscoord width = child->GetXULPrefSize(aState).width;
                childRect.width = clamped(width, min.width, max.width);
              }
            }
            else if (offsetSpecified & SPECIFIED_RIGHT) {
              nscoord width = child->GetXULPrefSize(aState).width;
              childRect.width = clamped(width, min.width, max.width);
              childRect.x = clientRect.XMost() - offset.right - margin.right - childRect.width;
            }

            if (offsetSpecified & SPECIFIED_TOP) {
              childRect.y = clientRect.y + offset.top + margin.top;
              if (offsetSpecified & SPECIFIED_BOTTOM) {
                nscoord height = clientRect.height - offset.TopBottom() - margin.TopBottom();
                childRect.height = clamped(height, min.height, max.height);
              }
              else {
                nscoord height = child->GetXULPrefSize(aState).height;
                childRect.height = clamped(height, min.height, max.height);
              }
            }
            else if (offsetSpecified & SPECIFIED_BOTTOM) {
              nscoord height = child->GetXULPrefSize(aState).height;
              childRect.height = clamped(height, min.height, max.height);
              childRect.y = clientRect.YMost() - offset.bottom - margin.bottom - childRect.height;
            }
          }

          // Now place the child.
          child->SetXULBounds(aState, childRect);

          // Flow the child.
          child->XULLayout(aState);

          // Get the child's new rect.
          childRect = child->GetRect();
          childRect.Inflate(margin);

          if (child->StyleXUL()->mStretchStack) {
            // Did the child push back on us and get bigger?
            if (offset.LeftRight() + childRect.width > clientRect.width) {
              clientRect.width = childRect.width + offset.LeftRight();
              grow = true;
            }

            if (offset.TopBottom() + childRect.height > clientRect.height) {
              clientRect.height = childRect.height + offset.TopBottom();
              grow = true;
            }
          }
       }

       child = nsBox::GetNextXULBox(child);
     }
   } while (grow);
   
   // if some HTML inside us got bigger we need to force ourselves to
   // get bigger
   nsRect bounds(aBox->GetRect());
   nsMargin bp;
   aBox->GetXULBorderAndPadding(bp);
   clientRect.Inflate(bp);

   if (clientRect.width > bounds.width || clientRect.height > bounds.height)
   {
     if (clientRect.width > bounds.width)
       bounds.width = clientRect.width;
     if (clientRect.height > bounds.height)
       bounds.height = clientRect.height;

     aBox->SetXULBounds(aState, bounds);
   }

   return NS_OK;
}