src/Widget/TwoWidgets.cpp

   1 /*
   2 Copyright_License {
   3
   4   XCSoar Glide Computer - http://www.xcsoar.org/
   5   Copyright (C) 2000-2013 The XCSoar Project
   6   A detailed list of copyright holders can be found in the file "AUTHORS".
   7
   8   This program is free software; you can redistribute it and/or
   9   modify it under the terms of the GNU General Public License
  10   as published by the Free Software Foundation; either version 2
  11   of the License, or (at your option) any later version.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21 }
  22 */
  23
  24 #include "TwoWidgets.hpp"
  25
  26 #include <algorithm>
  27
  28 TwoWidgets::~TwoWidgets()
  29 {
  30   delete second;
  31   delete first;
  32 }
  33
  34 void
  35 TwoWidgets::UpdateLayout()
  36 {
  37   const auto layout = CalculateLayout(rc);
  38   first->Move(layout.first);
  39   second->Move(layout.second);
  40 }
  41
  42 gcc_const
  43 static int
  44 CalculateSplit(int top, int bottom, unsigned min_a,
  45                unsigned min_b, unsigned max_b)
  46 {
  47   assert(bottom >= top);
  48   assert(min_b <= max_b);
  49
  50   const unsigned height = bottom - top;
  51
  52   if (min_a <= 0 || min_b <= 0)
  53     /* at least one Widet doesn't know its minimums size; there may be
  54        better solutions for this, but this workaround is good enough
  55        for fixing the assertion failure in DevicesConfigPanel */
  56     return (top + bottom) / 2;
  57   else if (height >= min_a + max_b)
  58     /* more than enough space: align the second Widget at the bottom
  59        and give the rest to the first Widget */
  60     return bottom - max_b;
  61   else if (height >= min_a + min_b)
  62     /* still somewhat enough space */
  63     return bottom - min_b;
  64   else {
  65     /* give the best for the rest */
  66     const PixelScalar first_height =
  67       std::min(min_a, height / 2);
  68     return top + first_height;
  69   }
  70 }
  71
  72 PixelScalar
  73 TwoWidgets::CalculateSplit(const PixelRect &rc) const
  74 {
  75   const PixelSize min_a = first->GetMinimumSize();
  76   const PixelSize min_b = second->GetMinimumSize();
  77   const PixelSize max_b = second->GetMaximumSize();
  78
  79   return vertical
  80     ? ::CalculateSplit(rc.top, rc.bottom, min_a.cy,
  81                        min_b.cy, max_b.cy)
  82     : ::CalculateSplit(rc.left, rc.right, min_a.cx,
  83                        min_b.cx, max_b.cx);
  84 }
  85
  86 std::pair<PixelRect,PixelRect>
  87 TwoWidgets::CalculateLayout(const PixelRect &rc) const
  88 {
  89   PixelRect a = rc, b = rc;
  90   if (vertical)
  91     a.bottom = b.top = CalculateSplit(rc);
  92   else
  93     a.right = b.left = CalculateSplit(rc);
  94   return std::make_pair(a, b);
  95 }
  96
  97 PixelSize
  98 TwoWidgets::GetMinimumSize() const
  99 {
 100   const PixelSize a = first->GetMinimumSize();
 101   const PixelSize b = second->GetMinimumSize();
 102
 103   return vertical
 104     ? PixelSize{ std::max(a.cx, b.cx), a.cy + b.cy }
 105     : PixelSize{ a.cx + b.cx, std::max(a.cy, b.cy) };
 106 }
 107
 108 PixelSize
 109 TwoWidgets::GetMaximumSize() const
 110 {
 111   const PixelSize a = first->GetMaximumSize();
 112   const PixelSize b = second->GetMaximumSize();
 113
 114   return vertical
 115     ? PixelSize{ std::max(a.cx, b.cx), a.cy + b.cy }
 116     : PixelSize{ a.cx + b.cx, std::max(a.cy, b.cy) };
 117 }
 118
 119 /**
 120  * Calculates a "dummy" layout that is splitted in the middle.  In
 121  * TwoWidgets::Initialise() and TwoWidgets::Prepare(), we are not
 122  * allowed to call Widget::GetMinimumSize() yet.
 123  */
 124 gcc_const
 125 static std::pair<PixelRect,PixelRect>
 126 DummyLayout(const PixelRect rc, bool vertical)
 127 {
 128   PixelRect a = rc, b = rc;
 129   if (vertical)
 130     a.bottom = b.top = (rc.top + rc.bottom) / 2;
 131   else
 132     a.right = b.left = (rc.left + rc.right) / 2;
 133   return std::make_pair(a, b);
 134 }
 135
 136 void
 137 TwoWidgets::Initialise(ContainerWindow &parent, const PixelRect &rc)
 138 {
 139   this->rc = rc;
 140   const auto layout = DummyLayout(rc, vertical);
 141   first->Initialise(parent, layout.first);
 142   second->Initialise(parent, layout.second);
 143 }
 144
 145 void
 146 TwoWidgets::Prepare(ContainerWindow &parent, const PixelRect &rc)
 147 {
 148   this->rc = rc;
 149   const auto layout = DummyLayout(rc, vertical);
 150   first->Prepare(parent, layout.first);
 151   second->Prepare(parent, layout.second);
 152 }
 153
 154 void
 155 TwoWidgets::Unprepare()
 156 {
 157   first->Unprepare();
 158   second->Unprepare();
 159 }
 160
 161 bool
 162 TwoWidgets::Save(bool &changed)
 163 {
 164   return first->Save(changed) && second->Save(changed);
 165 }
 166
 167 bool
 168 TwoWidgets::Click()
 169 {
 170   return first->Click() || second->Click();
 171 }
 172
 173 void
 174 TwoWidgets::ReClick()
 175 {
 176   first->ReClick();
 177   second->ReClick();
 178 }
 179
 180 void
 181 TwoWidgets::Show(const PixelRect &rc)
 182 {
 183   this->rc = rc;
 184   const auto layout = CalculateLayout(rc);
 185   first->Show(layout.first);
 186   second->Show(layout.second);
 187 }
 188
 189 bool
 190 TwoWidgets::Leave()
 191 {
 192   return first->Leave() && second->Leave();
 193 }
 194
 195 void
 196 TwoWidgets::Hide()
 197 {
 198   first->Hide();
 199   second->Hide();
 200 }
 201
 202 void
 203 TwoWidgets::Move(const PixelRect &rc)
 204 {
 205   this->rc = rc;
 206   const auto layout = CalculateLayout(rc);
 207   first->Move(layout.first);
 208   second->Move(layout.second);
 209 }
 210
 211 bool
 212 TwoWidgets::SetFocus()
 213 {
 214   return first->SetFocus() || second->SetFocus();
 215 }