layout/tables/BasicTableLayoutStrategy.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 // vim:cindent:ts=4:et:sw=4:
   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  * Web-compatible algorithms that determine column and table isizes,
   9  * used for CSS2's 'table-layout: auto'.
  10  */
  11
  12 #ifndef BasicTableLayoutStrategy_h_
  13 #define BasicTableLayoutStrategy_h_
  14
  15 #include "mozilla/Attributes.h"
  16 #include "nsITableLayoutStrategy.h"
  17
  18 class nsTableFrame;
  19
  20 class BasicTableLayoutStrategy : public nsITableLayoutStrategy {
  21  public:
  22   explicit BasicTableLayoutStrategy(nsTableFrame* aTableFrame);
  23   virtual ~BasicTableLayoutStrategy();
  24
  25   // nsITableLayoutStrategy implementation
  26   virtual nscoord GetMinISize(gfxContext* aRenderingContext) override;
  27   virtual nscoord GetPrefISize(gfxContext* aRenderingContext,
  28                                bool aComputingSize) override;
  29   virtual void MarkIntrinsicISizesDirty() override;
  30   virtual void ComputeColumnISizes(const ReflowInput& aReflowInput) override;
  31
  32  private:
  33   // NOTE: Using prefix "BTLS" to avoid overlapping names with
  34   // the values of mozilla::IntrinsicISizeType.
  35   enum class BtlsISizeType : uint8_t { MinISize, PrefISize, FinalISize };
  36
  37   // Compute intrinsic isize member variables on the columns.
  38   void ComputeColumnIntrinsicISizes(gfxContext* aRenderingContext);
  39
  40   // Distribute a colspanning cell's percent isize (if any) to its columns.
  41   void DistributePctISizeToColumns(float aSpanPrefPct, int32_t aFirstCol,
  42                                    int32_t aColCount);
  43
  44   // Distribute an isize of some BltsISizeType type to a set of columns.
  45   //  aISize: The amount of isize to be distributed
  46   //  aFirstCol: The index (in the table) of the first column to be
  47   //             considered for receiving isize
  48   //  aColCount: The number of consecutive columns (starting with aFirstCol)
  49   //             to be considered for receiving isize
  50   //  aISizeType: The type of isize being distributed.  (BTLS_MIN_ISIZE and
  51   //              BTLS_PREF_ISIZE are intended to be used for dividing up
  52   //              colspan's min & pref isize.  BTLS_FINAL_ISIZE is intended
  53   //              to be used for distributing the table's final isize across
  54   //              all its columns)
  55   //  aSpanHasSpecifiedISize: Should be true iff:
  56   //                           - We're distributing a colspanning cell's
  57   //                             pref or min isize to its columns
  58   //                           - The colspanning cell has a specified isize.
  59   void DistributeISizeToColumns(nscoord aISize, int32_t aFirstCol,
  60                                 int32_t aColCount, BtlsISizeType aISizeType,
  61                                 bool aSpanHasSpecifiedISize);
  62
  63   // Compute the min and pref isizes of the table from the isize
  64   // variables on the columns.
  65   void ComputeIntrinsicISizes(gfxContext* aRenderingContext);
  66
  67   nsTableFrame* mTableFrame;
  68   nscoord mMinISize;
  69   nscoord mPrefISize;
  70   nscoord mPrefISizePctExpand;
  71   nscoord mLastCalcISize;
  72 };
  73
  74 #endif /* !defined(BasicTableLayoutStrategy_h_) */