examples/declarative/qtquick1/cppextensions/qgraphicslayouts/qgraphicslinearlayout/linearlayout.cpp

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  40
  41 #include "linearlayout.h"
  42
  43 #include <QGraphicsWidget>
  44 #include <QGraphicsLayoutItem>
  45
  46 LinearLayoutAttached::LinearLayoutAttached(QObject *parent)
  47 : QObject(parent), m_stretch(1), m_alignment(Qt::AlignTop), m_spacing(0)
  48 {
  49 }
  50
  51 void LinearLayoutAttached::setStretchFactor(int f)
  52 {
  53     if (m_stretch != f) {
  54         m_stretch = f;
  55         emit stretchChanged(reinterpret_cast<QGraphicsLayoutItem*>(parent()), m_stretch);
  56     }
  57 }
  58
  59 void LinearLayoutAttached::setSpacing(int s)
  60 {
  61     if (m_spacing != s) {
  62         m_spacing = s;
  63         emit spacingChanged(reinterpret_cast<QGraphicsLayoutItem*>(parent()), m_spacing);
  64     }
  65 }
  66
  67 void LinearLayoutAttached::setAlignment(Qt::Alignment a)
  68 {
  69     if (m_alignment != a) {
  70         m_alignment = a;
  71         emit alignmentChanged(reinterpret_cast<QGraphicsLayoutItem*>(parent()), m_alignment);
  72     }
  73 }
  74
  75 GraphicsLinearLayoutStretchItemObject::GraphicsLinearLayoutStretchItemObject(QObject *parent)
  76     : QObject(parent)
  77 {
  78 }
  79
  80 QSizeF GraphicsLinearLayoutStretchItemObject::sizeHint(Qt::SizeHint which, const QSizeF &constraint) const
  81 {
  82     Q_UNUSED(which);
  83     Q_UNUSED(constraint);
  84     return QSizeF();
  85 }
  86
  87
  88 GraphicsLinearLayoutObject::GraphicsLinearLayoutObject(QObject *parent)
  89 : QObject(parent)
  90 {
  91 }
  92
  93 GraphicsLinearLayoutObject::~GraphicsLinearLayoutObject()
  94 {
  95 }
  96
  97 void GraphicsLinearLayoutObject::insertLayoutItem(int index, QGraphicsLayoutItem *item)
  98 {
  99     insertItem(index, item);
 100
 101     if (LinearLayoutAttached *obj = attachedProperties.value(item)) {
 102         setStretchFactor(item, obj->stretchFactor());
 103         setAlignment(item, obj->alignment());
 104         updateSpacing(item, obj->spacing());
 105         QObject::connect(obj, SIGNAL(stretchChanged(QGraphicsLayoutItem*,int)),
 106                          this, SLOT(updateStretch(QGraphicsLayoutItem*,int)));
 107         QObject::connect(obj, SIGNAL(alignmentChanged(QGraphicsLayoutItem*,Qt::Alignment)),
 108                          this, SLOT(updateAlignment(QGraphicsLayoutItem*,Qt::Alignment)));
 109         QObject::connect(obj, SIGNAL(spacingChanged(QGraphicsLayoutItem*,int)),
 110                          this, SLOT(updateSpacing(QGraphicsLayoutItem*,int)));
 111     }
 112 }
 113
 114 void GraphicsLinearLayoutObject::removeAt(int index)
 115 {
 116     QGraphicsLayoutItem *item = itemAt(index);
 117     if (item) {
 118         LinearLayoutAttached *obj = attachedProperties.value(item);
 119         obj->disconnect(this);
 120         attachedProperties.remove(item);
 121     }
 122     QGraphicsLinearLayout::removeAt(index);
 123 }
 124
 125 void GraphicsLinearLayoutObject::clearChildren()
 126 {
 127     // do not delete the removed items; they will be deleted by the QML engine
 128     while (count() > 0)
 129         removeAt(count()-1);
 130 }
 131
 132 qreal GraphicsLinearLayoutObject::contentsMargin() const
 133 {
 134     qreal a, b, c, d;
 135     getContentsMargins(&a, &b, &c, &d);
 136     if (a == b && a == c && a == d)
 137         return a;
 138     return -1;
 139 }
 140
 141 void GraphicsLinearLayoutObject::setContentsMargin(qreal m)
 142 {
 143     setContentsMargins(m, m, m, m);
 144 }
 145
 146 void GraphicsLinearLayoutObject::updateStretch(QGraphicsLayoutItem *item, int stretch)
 147 {
 148     QGraphicsLinearLayout::setStretchFactor(item, stretch);
 149 }
 150
 151 void GraphicsLinearLayoutObject::updateSpacing(QGraphicsLayoutItem* item, int spacing)
 152 {
 153     for (int i=0; i < count(); i++){
 154         if (itemAt(i) == item) {
 155             QGraphicsLinearLayout::setItemSpacing(i, spacing);
 156             return;
 157         }
 158     }
 159 }
 160
 161 void GraphicsLinearLayoutObject::updateAlignment(QGraphicsLayoutItem *item, Qt::Alignment alignment)
 162 {
 163     QGraphicsLinearLayout::setAlignment(item, alignment);
 164 }
 165
 166 QHash<QGraphicsLayoutItem*, LinearLayoutAttached*> GraphicsLinearLayoutObject::attachedProperties;
 167 LinearLayoutAttached *GraphicsLinearLayoutObject::qmlAttachedProperties(QObject *obj)
 168 {
 169     LinearLayoutAttached *rv = new LinearLayoutAttached(obj);
 170     if (qobject_cast<QGraphicsLayoutItem*>(obj))
 171         attachedProperties.insert(qobject_cast<QGraphicsLayoutItem*>(obj), rv);
 172     return rv;
 173 }
 174
 175