pv/widgets/flowlayout.cpp

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  40
  41 #include <QWidget>
  42
  43 #include "flowlayout.hpp"
  44
  45 FlowLayout::FlowLayout(QWidget *parent, int margin, int hSpacing, int vSpacing) :
  46         QLayout(parent),
  47         m_parent(parent),
  48         m_hSpace(hSpacing),
  49         m_vSpace(vSpacing)
  50 {
  51         setContentsMargins(margin, margin, margin, margin);
  52 }
  53
  54 FlowLayout::FlowLayout(int margin, int hSpacing, int vSpacing) :
  55         m_parent(nullptr),
  56         m_hSpace(hSpacing),
  57         m_vSpace(vSpacing)
  58 {
  59         setContentsMargins(margin, margin, margin, margin);
  60 }
  61
  62 FlowLayout::~FlowLayout()
  63 {
  64         QLayoutItem *item;
  65         while ((item = takeAt(0)))
  66                 delete item;
  67 }
  68
  69 void FlowLayout::addItem(QLayoutItem *item)
  70 {
  71         itemList.append(item);
  72 }
  73
  74 int FlowLayout::horizontalSpacing() const
  75 {
  76         if (m_hSpace >= 0)
  77                 return m_hSpace;
  78         else
  79                 return smartSpacing(QStyle::PM_LayoutHorizontalSpacing);
  80 }
  81
  82 int FlowLayout::verticalSpacing() const
  83 {
  84         if (m_vSpace >= 0)
  85                 return m_vSpace;
  86         else
  87                 return smartSpacing(QStyle::PM_LayoutVerticalSpacing);
  88 }
  89
  90 int FlowLayout::count() const
  91 {
  92         return itemList.size();
  93 }
  94
  95 QLayoutItem *FlowLayout::itemAt(int index) const
  96 {
  97         return itemList.value(index);
  98 }
  99
 100 QLayoutItem *FlowLayout::takeAt(int index)
 101 {
 102         if ((index >= 0) && (index < itemList.size()))
 103                 return itemList.takeAt(index);
 104         else
 105                 return nullptr;
 106 }
 107
 108 Qt::Orientations FlowLayout::expandingDirections() const
 109 {
 110         return Qt::Horizontal | Qt::Vertical;
 111 }
 112
 113 bool FlowLayout::hasHeightForWidth() const
 114 {
 115         return true;
 116 }
 117
 118 int FlowLayout::heightForWidth(int width) const
 119 {
 120         int height = doLayout(QRect(0, 0, width, 0), true);
 121         return height;
 122 }
 123
 124 void FlowLayout::setGeometry(const QRect &rect)
 125 {
 126         QLayout::setGeometry(rect);
 127         doLayout(rect, false);
 128 }
 129
 130 QSize FlowLayout::sizeHint() const
 131 {
 132         return minimumSize();
 133 }
 134
 135 QSize FlowLayout::minimumSize() const
 136 {
 137         QSize size(0, 0);
 138
 139         for (QLayoutItem* item : itemList) {
 140                 int w = item->geometry().x() + item->geometry().width();
 141                 if (w > size.width())
 142                         size.setWidth(w);
 143
 144                 int h = item->geometry().y() + item->geometry().height();
 145                 if (h > size.height())
 146                         size.setHeight(h);
 147         }
 148
 149         size += QSize(2 * margin(), 2 * margin());
 150
 151         return size;
 152 }
 153
 154 int FlowLayout::doLayout(const QRect &rect, bool testOnly) const
 155 {
 156         int left, top, right, bottom;
 157         getContentsMargins(&left, &top, &right, &bottom);
 158
 159         QRect effectiveRect = rect.adjusted(left, top, -right, -bottom);
 160         int x = effectiveRect.x();
 161         int y = effectiveRect.y();
 162
 163         int lineHeight = 0;
 164         for (QLayoutItem* item : itemList) {
 165                 QWidget* w = item->widget();
 166
 167                 int spaceX = horizontalSpacing();
 168                 if (spaceX == -1)
 169                         spaceX = w->style()->layoutSpacing(
 170                                 QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Horizontal);
 171
 172                 int spaceY = verticalSpacing();
 173                 if (spaceY == -1)
 174                         spaceY = w->style()->layoutSpacing(
 175                                 QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Vertical);
 176
 177                 int nextX = x + item->sizeHint().width() + spaceX;
 178                 if (((nextX - spaceX) > effectiveRect.right()) && (lineHeight > 0)) {
 179                         x = effectiveRect.x();
 180                         y = y + lineHeight + spaceY;
 181                         nextX = x + item->sizeHint().width() + spaceX;
 182                         lineHeight = 0;
 183                 }
 184
 185                 if (!testOnly)
 186                         item->setGeometry(QRect(QPoint(x, y), item->sizeHint()));
 187
 188                 x = nextX;
 189                 lineHeight = qMax(lineHeight, item->sizeHint().height());
 190         }
 191
 192         int height = y + lineHeight - rect.y() + bottom;
 193
 194         if (m_parent)
 195                 m_parent->setMinimumHeight(height);
 196
 197         return height;
 198 }
 199
 200 int FlowLayout::smartSpacing(QStyle::PixelMetric pm) const
 201 {
 202         QObject *parent = this->parent();
 203
 204         if (!parent)
 205                 return -1;
 206
 207         if (parent->isWidgetType()) {
 208                 QWidget *pw = qobject_cast<QWidget*>(parent);
 209                 return pw->style()->pixelMetric(pm, nullptr, pw);
 210         } else
 211                 return static_cast<QLayout*>(parent)->spacing();
 212 }