diff options
Diffstat (limited to 'src/declarative/items/qsgpositioners.cpp')
| -rw-r--r-- | src/declarative/items/qsgpositioners.cpp | 755 |
1 files changed, 737 insertions, 18 deletions
diff --git a/src/declarative/items/qsgpositioners.cpp b/src/declarative/items/qsgpositioners.cpp index da3c7fea04..fca0aa1877 100644 --- a/src/declarative/items/qsgpositioners.cpp +++ b/src/declarative/items/qsgpositioners.cpp @@ -50,6 +50,7 @@ #include <private/qdeclarativestate_p.h> #include <private/qdeclarativestategroup_p.h> #include <private/qdeclarativestateoperations_p.h> +#include <private/qdeclarativetransition_p.h> QT_BEGIN_NAMESPACE @@ -77,6 +78,22 @@ QSGBasePositioner::QSGBasePositioner(PositionerType at, QSGItem *parent) Q_D(QSGBasePositioner); d->init(at); } +/*! + \internal + \class QSGBasePositioner + \brief The QSGBasePositioner class provides a base for QSGGraphics layouts. + + To create a QSGGraphics Positioner, simply subclass QSGBasePositioner and implement + doLayout(), which is automatically called when the layout might need + updating. In doLayout() use the setX and setY functions from QSGBasePositioner, and the + base class will apply the positions along with the appropriate transitions. The items to + position are provided in order as the protected member positionedItems. + + You also need to set a PositionerType, to declare whether you are positioning the x, y or both + for the child items. Depending on the chosen type, only x or y changes will be applied. + + Note that the subclass is responsible for adding the spacing in between items. +*/ QSGBasePositioner::QSGBasePositioner(QSGBasePositionerPrivate &dd, PositionerType at, QSGItem *parent) : QSGImplicitSizeItem(dd, parent) @@ -213,7 +230,8 @@ void QSGBasePositioner::prePositioning() } QSizeF contentSize(0,0); doPositioning(&contentSize); - if(d->addTransition || d->moveTransition) + updateAttachedProperties(); + if (!d->addActions.isEmpty() || !d->moveActions.isEmpty()) finishApplyTransitions(); d->doingPositioning = false; //Set implicit size to the size of its children @@ -226,12 +244,12 @@ void QSGBasePositioner::positionX(int x, const PositionedItem &target) Q_D(QSGBasePositioner); if(d->type == Horizontal || d->type == Both){ if (target.isNew) { - if (!d->addTransition) + if (!d->addTransition || !d->addTransition->enabled()) target.item->setX(x); else d->addActions << QDeclarativeAction(target.item, QLatin1String("x"), QVariant(x)); } else if (x != target.item->x()) { - if (!d->moveTransition) + if (!d->moveTransition || !d->moveTransition->enabled()) target.item->setX(x); else d->moveActions << QDeclarativeAction(target.item, QLatin1String("x"), QVariant(x)); @@ -244,12 +262,12 @@ void QSGBasePositioner::positionY(int y, const PositionedItem &target) Q_D(QSGBasePositioner); if(d->type == Vertical || d->type == Both){ if (target.isNew) { - if (!d->addTransition) + if (!d->addTransition || !d->addTransition->enabled()) target.item->setY(y); else d->addActions << QDeclarativeAction(target.item, QLatin1String("y"), QVariant(y)); } else if (y != target.item->y()) { - if (!d->moveTransition) + if (!d->moveTransition || !d->moveTransition->enabled()) target.item->setY(y); else d->moveActions << QDeclarativeAction(target.item, QLatin1String("y"), QVariant(y)); @@ -268,6 +286,233 @@ void QSGBasePositioner::finishApplyTransitions() d->moveActions.clear(); } +QSGPositionerAttached *QSGBasePositioner::qmlAttachedProperties(QObject *obj) +{ + return new QSGPositionerAttached(obj); +} + +void QSGBasePositioner::updateAttachedProperties(QSGPositionerAttached *specificProperty, QSGItem *specificPropertyOwner) const +{ + // If this function is deemed too expensive or shows up in profiles, it could + // be changed to run only when there are attached properties present. This + // could be a flag in the positioner that is set by the attached property + // constructor. + QSGPositionerAttached *prevLastProperty = 0; + QSGPositionerAttached *lastProperty = 0; + + int visibleItemIndex = 0; + for (int ii = 0; ii < positionedItems.count(); ++ii) { + const PositionedItem &child = positionedItems.at(ii); + if (!child.item) + continue; + + QSGPositionerAttached *property = 0; + + if (specificProperty) { + if (specificPropertyOwner == child.item) { + property = specificProperty; + } + } else { + property = static_cast<QSGPositionerAttached *>(qmlAttachedPropertiesObject<QSGBasePositioner>(child.item, false)); + } + + if (child.isVisible) { + if (property) { + property->setIndex(visibleItemIndex); + property->setIsFirstItem(visibleItemIndex == 0); + + if (property->isLastItem()) + prevLastProperty = property; + } + + lastProperty = property; + ++visibleItemIndex; + } else if (property) { + property->setIndex(-1); + property->setIsFirstItem(false); + property->setIsLastItem(false); + } + } + + if (prevLastProperty && prevLastProperty != lastProperty) + prevLastProperty->setIsLastItem(false); + if (lastProperty) + lastProperty->setIsLastItem(true); +} + +/*! + \qmlclass Positioner QSGPositionerAttached + \inqmlmodule QtQuick 2 + \ingroup qml-positioning-elements + \brief The Positioner type provides attached properties that contain details on where an item exists in a positioner. + + Positioner items (such as Column, Row, Flow and Grid) provide automatic layout + for child items. Attaching this property allows a child item to determine + where it exists within the positioner. +*/ + +QSGPositionerAttached::QSGPositionerAttached(QObject *parent) : QObject(parent), m_index(-1), m_isFirstItem(false), m_isLastItem(false) +{ + QSGItem *attachedItem = qobject_cast<QSGItem *>(parent); + if (attachedItem) { + QSGBasePositioner *positioner = qobject_cast<QSGBasePositioner *>(attachedItem->parent()); + if (positioner) { + positioner->updateAttachedProperties(this, attachedItem); + } + } +} + +/*! + \qmlattachedproperty Item QtQuick2::Positioner::index + + This property allows the item to determine + its index within the positioner. +*/ +void QSGPositionerAttached::setIndex(int index) +{ + if (m_index == index) + return; + m_index = index; + emit indexChanged(); +} + +/*! + \qmlattachedproperty Item QtQuick2::Positioner::isFirstItem + \qmlattachedproperty Item QtQuick2::Positioner::isLastItem + + These properties allow the item to determine if it + is the first or last item in the positioner, respectively. +*/ +void QSGPositionerAttached::setIsFirstItem(bool isFirstItem) +{ + if (m_isFirstItem == isFirstItem) + return; + m_isFirstItem = isFirstItem; + emit isFirstItemChanged(); +} + +void QSGPositionerAttached::setIsLastItem(bool isLastItem) +{ + if (m_isLastItem == isLastItem) + return; + m_isLastItem = isLastItem; + emit isLastItemChanged(); +} + +/*! + \qmlclass Column QSGColumn + \inqmlmodule QtQuick 2 + \ingroup qml-positioning-elements + \brief The Column item arranges its children vertically. + \inherits Item + + The Column item positions its child items so that they are vertically + aligned and not overlapping. + + Spacing between items can be added using the \l spacing property. + Transitions can be used for cases where items managed by a Column are + added or moved. These are stored in the \l add and \l move properties + respectively. + + See \l{Using QML Positioner and Repeater Items} for more details about this item and other + related items. + + \section1 Example Usage + + The following example positions differently shaped rectangles using a Column + item. + + \image verticalpositioner_example.png + + \snippet doc/src/snippets/declarative/column/vertical-positioner.qml document + + \section1 Using Transitions + + Transitions can be used to animate items that are added to, moved within, + or removed from a Column item. The \l add and \l move properties can be set to + the transitions that will be applied when items are added to, removed from, + or re-positioned within a Column item. + + The use of transitions with positioners is described in more detail in the + \l{Using QML Positioner and Repeater Items#Using Transitions}{Using QML + Positioner and Repeater Items} document. + + \image verticalpositioner_transition.gif + + \qml + Column { + spacing: 2 + add: Transition { + // Define an animation for adding a new item... + } + move: Transition { + // Define an animation for moving items within the column... + } + // ... + } + \endqml + + \section1 Limitations + + Note that the positioner assumes that the x and y positions of its children + will not change. If you manually change the x or y properties in script, bind + the x or y properties, use anchors on a child of a positioner, or have the + height of a child depend on the position of a child, then the + positioner may exhibit strange behavior. If you need to perform any of these + actions, consider positioning the items without the use of a Column. + + Items with a width or height of 0 will not be positioned. + + \sa Row, Grid, Flow, Positioner, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty Transition QtQuick2::Column::add + + This property holds the transition to be applied when adding an + item to the positioner. The transition will only be applied to the + added item(s). Positioner transitions will only affect the + position (x, y) of items. + + For a positioner, adding an item can mean that either the object + has been created or reparented, and thus is now a child or the + positioner, or that the object has had its opacity increased from + zero, and thus is now visible. + + \sa move +*/ +/*! + \qmlproperty Transition QtQuick2::Column::move + + This property holds the transition to apply when moving an item + within the positioner. Positioner transitions will only affect + the position (x, y) of items. + + This transition can be performed when other items are added or removed + from the positioner, or when items resize themselves. + + \image positioner-move.gif + + \qml + Column { + move: Transition { + NumberAnimation { + properties: "y" + duration: 1000 + } + } + } + \endqml + + \sa add, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty int QtQuick2::Column::spacing + + The spacing is the amount in pixels left empty between adjacent + items. The default spacing is 0. + + \sa Grid::spacing +*/ QSGColumn::QSGColumn(QSGItem *parent) : QSGBasePositioner(Vertical, parent) { @@ -288,10 +533,11 @@ void QSGColumn::doPositioning(QSizeF *contentSize) contentSize->setWidth(qMax(contentSize->width(), child.item->width())); voffset += child.item->height(); - if (ii != positionedItems.count() - 1) - voffset += spacing(); + voffset += spacing(); } + if (voffset != 0)//If we positioned any items, undo the spacing from the last item + voffset -= spacing(); contentSize->setHeight(voffset); } @@ -318,11 +564,119 @@ void QSGColumn::reportConflictingAnchors() qmlInfo(this) << "Cannot specify top, bottom, verticalCenter, fill or centerIn anchors for items inside Column"; } } +/*! + \qmlclass Row QSGRow + \inqmlmodule QtQuick 2 + \ingroup qml-positioning-elements + \brief The Row item arranges its children horizontally. + \inherits Item + + The Row item positions its child items so that they are horizontally + aligned and not overlapping. + + Use \l spacing to set the spacing between items in a Row, and use the + \l add and \l move properties to set the transitions that should be applied + when items are added to, removed from, or re-positioned within the Row. + + See \l{Using QML Positioner and Repeater Items} for more details about this item and other + related items. + + \section1 Example Usage + + The following example lays out differently shaped rectangles using a Row. + + \image horizontalpositioner_example.png + + \snippet doc/src/snippets/declarative/row/row.qml document + + \section1 Using Transitions + + Transitions can be used to animate items that are added to, moved within, + or removed from a Grid item. The \l add and \l move properties can be set to + the transitions that will be applied when items are added to, removed from, + or re-positioned within a Row item. + + \section1 Limitations + + Note that the positioner assumes that the x and y positions of its children + will not change. If you manually change the x or y properties in script, bind + the x or y properties, use anchors on a child of a positioner, or have the + width of a child depend on the position of a child, then the + positioner may exhibit strange behaviour. If you need to perform any of these + actions, consider positioning the items without the use of a Row. + + Items with a width or height of 0 will not be positioned. + + \sa Column, Grid, Flow, Positioner, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty Transition QtQuick2::Row::add + + This property holds the transition to be applied when adding an + item to the positioner. The transition will only be applied to the + added item(s). Positioner transitions will only affect the + position (x, y) of items. + + For a positioner, adding an item can mean that either the object + has been created or reparented, and thus is now a child or the + positioner, or that the object has had its opacity increased from + zero, and thus is now visible. + + \sa move +*/ +/*! + \qmlproperty Transition QtQuick2::Row::move + + This property holds the transition to be applied when moving an + item within the positioner. Positioner transitions will only affect + the position (x, y) of items. + + This transition can be performed when other items are added or removed + from the positioner, or when items resize themselves. + + \qml + Row { + id: positioner + move: Transition { + NumberAnimation { + properties: "x" + duration: 1000 + } + } + } + \endqml + + \sa add, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty int QtQuick2::Row::spacing + + The spacing is the amount in pixels left empty between adjacent + items. The default spacing is 0. + + \sa Grid::spacing +*/ QSGRow::QSGRow(QSGItem *parent) : QSGBasePositioner(Horizontal, parent) { } +/*! + \qmlproperty enumeration QtQuick2::Row::layoutDirection + + This property holds the layoutDirection of the row. + + Possible values: + + \list + \o Qt.LeftToRight (default) - Items are laid out from left to right. If the width of the row is explicitly set, + the left anchor remains to the left of the row. + \o Qt.RightToLeft - Items are laid out from right to left. If the width of the row is explicitly set, + the right anchor remains to the right of the row. + \endlist + + \sa Grid::layoutDirection, Flow::layoutDirection, {declarative/righttoleft/layoutdirection}{Layout directions example} +*/ Qt::LayoutDirection QSGRow::layoutDirection() const { @@ -344,6 +698,16 @@ void QSGRow::setLayoutDirection(Qt::LayoutDirection layoutDirection) emit effectiveLayoutDirectionChanged(); } } +/*! + \qmlproperty enumeration QtQuick2::Row::effectiveLayoutDirection + This property holds the effective layout direction of the row positioner. + + When using the attached property \l {LayoutMirroring::enabled}{LayoutMirroring::enabled} for locale layouts, + the visual layout direction of the row positioner will be mirrored. However, the + property \l {Row::layoutDirection}{layoutDirection} will remain unchanged. + + \sa Row::layoutDirection, {LayoutMirroring}{LayoutMirroring} +*/ Qt::LayoutDirection QSGRow::effectiveLayoutDirection() const { @@ -371,10 +735,11 @@ void QSGRow::doPositioning(QSizeF *contentSize) contentSize->setHeight(qMax(contentSize->height(), child.item->height())); hoffset += child.item->width(); - if (ii != positionedItems.count() - 1) - hoffset += spacing(); + hoffset += spacing(); } + if (hoffset != 0)//If we positioned any items, undo the extra spacing from the last item + hoffset -= spacing(); contentSize->setWidth(hoffset); if (d->isLeftToRight()) @@ -421,11 +786,138 @@ void QSGRow::reportConflictingAnchors() qmlInfo(this) << "Cannot specify left, right, horizontalCenter, fill or centerIn anchors for items inside Row"; } +/*! + \qmlclass Grid QSGGrid + \inqmlmodule QtQuick 2 + \ingroup qml-positioning-elements + \brief The Grid item positions its children in a grid. + \inherits Item + + The Grid item positions its child items so that they are + aligned in a grid and are not overlapping. + + The grid positioner calculates a grid of rectangular cells of sufficient + size to hold all items, placing the items in the cells, from left to right + and top to bottom. Each item is positioned in the top-left corner of its + cell with position (0, 0). + + A Grid defaults to four columns, and as many rows as are necessary to + fit all child items. The number of rows and columns can be constrained + by setting the \l rows and \l columns properties. + + Spacing can be added between child items by setting the \l spacing + property. The amount of spacing applied will be the same in the + horizontal and vertical directions. + + See \l{Using QML Positioner and Repeater Items} for more details about this item and other + related items. + + \section1 Example Usage + + The following example demonstrates this. + + \image gridLayout_example.png + + \snippet doc/src/snippets/declarative/grid/grid.qml document + + \section1 Using Transitions + + Transitions can be used to animate items that are added to, moved within, + or removed from a Grid item. The \l add and \l move properties can be set to + the transitions that will be applied when items are added to, removed from, + or re-positioned within a Grid item. + + \section1 Limitations + + Note that the positioner assumes that the x and y positions of its children + will not change. If you manually change the x or y properties in script, bind + the x or y properties, use anchors on a child of a positioner, or have the + width or height of a child depend on the position of a child, then the + positioner may exhibit strange behaviour. If you need to perform any of these + actions, consider positioning the items without the use of a Grid. + + Items with a width or height of 0 will not be positioned. + + \sa Flow, Row, Column, Positioner, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty Transition QtQuick2::Grid::add + + This property holds the transition to be applied when adding an + item to the positioner. The transition will only be applied to the + added item(s). Positioner transitions will only affect the + position (x, y) of items. + + For a positioner, adding an item can mean that either the object + has been created or reparented, and thus is now a child or the + positioner, or that the object has had its opacity increased from + zero, and thus is now visible. + + \sa move +*/ +/*! + \qmlproperty Transition QtQuick2::Grid::move + + This property holds the transition to be applied when moving an + item within the positioner. Positioner transitions will only affect + the position (x, y) of items. + + This transition can be performed when other items are added or removed + from the positioner, or when items resize themselves. + + \qml + Grid { + move: Transition { + NumberAnimation { + properties: "x,y" + duration: 1000 + } + } + } + \endqml + + \sa add, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty int QtQuick2::Grid::spacing + + The spacing is the amount in pixels left empty between adjacent + items. The default spacing is 0. + + The below example places a Grid containing a red, a blue and a + green rectangle on a gray background. The area the grid positioner + occupies is colored white. The positioner on the left has the + no spacing (the default), and the positioner on the right has + a spacing of 6. + + \inlineimage qml-grid-no-spacing.png + \inlineimage qml-grid-spacing.png + + \sa rows, columns +*/ QSGGrid::QSGGrid(QSGItem *parent) : - QSGBasePositioner(Both, parent), m_rows(-1), m_columns(-1), m_flow(LeftToRight) + QSGBasePositioner(Both, parent), m_rows(-1), m_columns(-1), m_rowSpacing(-1), m_columnSpacing(-1), m_flow(LeftToRight) { } +/*! + \qmlproperty int QtQuick2::Grid::columns + + This property holds the number of columns in the grid. The default + number of columns is 4. + + If the grid does not have enough items to fill the specified + number of columns, some columns will be of zero width. +*/ + +/*! + \qmlproperty int QtQuick2::Grid::rows + This property holds the number of rows in the grid. + + If the grid does not have enough items to fill the specified + number of rows, some rows will be of zero width. +*/ + void QSGGrid::setColumns(const int columns) { if (columns == m_columns) @@ -444,6 +936,19 @@ void QSGGrid::setRows(const int rows) emit rowsChanged(); } +/*! + \qmlproperty enumeration QtQuick2::Grid::flow + This property holds the flow of the layout. + + Possible values are: + + \list + \o Grid.LeftToRight (default) - Items are positioned next to + each other in the \l layoutDirection, then wrapped to the next line. + \o Grid.TopToBottom - Items are positioned next to each + other from top to bottom, then wrapped to the next column. + \endlist +*/ QSGGrid::Flow QSGGrid::flow() const { return m_flow; @@ -458,6 +963,58 @@ void QSGGrid::setFlow(Flow flow) } } +/*! + \qmlproperty int QtQuick2::Grid::rowSpacing + + This property holds the spacing in pixels between rows. + + \sa columnSpacing + \since QtQuick2.0 +*/ +void QSGGrid::setRowSpacing(const int rowSpacing) +{ + if (rowSpacing == m_rowSpacing) + return; + m_rowSpacing = rowSpacing; + prePositioning(); + emit rowSpacingChanged(); +} + +/*! + \qmlproperty int QtQuick2::Grid::columnSpacing + + This property holds the spacing in pixels between columns. + + \sa rowSpacing + \since QtQuick2.0 +*/ +void QSGGrid::setColumnSpacing(const int columnSpacing) +{ + if (columnSpacing == m_columnSpacing) + return; + m_columnSpacing = columnSpacing; + prePositioning(); + emit columnSpacingChanged(); +} + +/*! + \qmlproperty enumeration QtQuick2::Grid::layoutDirection + + This property holds the layout direction of the layout. + + Possible values are: + + \list + \o Qt.LeftToRight (default) - Items are positioned from the top to bottom, + and left to right. The flow direction is dependent on the + \l Grid::flow property. + \o Qt.RightToLeft - Items are positioned from the top to bottom, + and right to left. The flow direction is dependent on the + \l Grid::flow property. + \endlist + + \sa Flow::layoutDirection, Row::layoutDirection, {declarative/righttoleft/layoutdirection}{Layout directions example} +*/ Qt::LayoutDirection QSGGrid::layoutDirection() const { return QSGBasePositionerPrivate::getLayoutDirection(this); @@ -479,6 +1036,16 @@ void QSGGrid::setLayoutDirection(Qt::LayoutDirection layoutDirection) } } +/*! + \qmlproperty enumeration QtQuick2::Grid::effectiveLayoutDirection + This property holds the effective layout direction of the grid positioner. + + When using the attached property \l {LayoutMirroring::enabled}{LayoutMirroring::enabled} for locale layouts, + the visual layout direction of the grid positioner will be mirrored. However, the + property \l {Grid::layoutDirection}{layoutDirection} will remain unchanged. + + \sa Grid::layoutDirection, {LayoutMirroring}{LayoutMirroring} +*/ Qt::LayoutDirection QSGGrid::effectiveLayoutDirection() const { return QSGBasePositionerPrivate::getEffectiveLayoutDirection(this); @@ -550,17 +1117,25 @@ void QSGGrid::doPositioning(QSizeF *contentSize) } } + int columnSpacing = m_columnSpacing; + if (columnSpacing == -1) + columnSpacing = spacing(); + + int rowSpacing = m_rowSpacing; + if (rowSpacing == -1) + rowSpacing = spacing(); + int widthSum = 0; for (int j=0; j < maxColWidth.size(); j++){ if (j) - widthSum += spacing(); + widthSum += columnSpacing; widthSum += maxColWidth[j]; } int heightSum = 0; for (int i=0; i < maxRowHeight.size(); i++){ if (i) - heightSum += spacing(); + heightSum += rowSpacing; heightSum += maxRowHeight[i]; } @@ -591,13 +1166,13 @@ void QSGGrid::doPositioning(QSizeF *contentSize) if (m_flow == LeftToRight) { if (d->isLeftToRight()) - xoffset += maxColWidth[curCol]+spacing(); + xoffset += maxColWidth[curCol]+columnSpacing; else - xoffset -= maxColWidth[curCol]+spacing(); + xoffset -= maxColWidth[curCol]+columnSpacing; curCol++; curCol%=c; if (!curCol){ - yoffset += maxRowHeight[curRow]+spacing(); + yoffset += maxRowHeight[curRow]+rowSpacing; if (d->isLeftToRight()) xoffset = 0; else @@ -607,14 +1182,14 @@ void QSGGrid::doPositioning(QSizeF *contentSize) break; } } else { - yoffset+=maxRowHeight[curRow]+spacing(); + yoffset+=maxRowHeight[curRow]+rowSpacing; curRow++; curRow%=r; if (!curRow){ if (d->isLeftToRight()) - xoffset += maxColWidth[curCol]+spacing(); + xoffset += maxColWidth[curCol]+columnSpacing; else - xoffset -= maxColWidth[curCol]+spacing(); + xoffset -= maxColWidth[curCol]+columnSpacing; yoffset=0; curCol++; if (curCol>=c) @@ -641,6 +1216,105 @@ void QSGGrid::reportConflictingAnchors() qmlInfo(this) << "Cannot specify anchors for items inside Grid"; } +/*! + \qmlclass Flow QSGFlow + \inqmlmodule QtQuick 2 + \ingroup qml-positioning-elements + \brief The Flow item arranges its children side by side, wrapping as necessary. + \inherits Item + + The Flow item positions its child items like words on a page, wrapping them + to create rows or columns of items that do not overlap. + + Spacing between items can be added using the \l spacing property. + Transitions can be used for cases where items managed by a Column are + added or moved. These are stored in the \l add and \l move properties + respectively. + + See \l{Using QML Positioner and Repeater Items} for more details about this item and other + related items. + + \section1 Example Usage + + The following example positions \l Text items within a parent item using + a Flow item. + + \image qml-flow-snippet.png + + \snippet doc/src/snippets/declarative/flow.qml flow item + + \section1 Using Transitions + + Transitions can be used to animate items that are added to, moved within, + or removed from a Flow item. The \l add and \l move properties can be set to + the transitions that will be applied when items are added to, removed from, + or re-positioned within a Flow item. + + The use of transitions with positioners is described in more detail in the + \l{Using QML Positioner and Repeater Items#Using Transitions}{Using QML + Positioner and Repeater Items} document. + + \section1 Limitations + + Note that the positioner assumes that the x and y positions of its children + will not change. If you manually change the x or y properties in script, bind + the x or y properties, use anchors on a child of a positioner, or have the + width or height of a child depend on the position of a child, then the + positioner may exhibit strange behaviour. If you need to perform any of these + actions, consider positioning the items without the use of a Flow. + + Items with a width or height of 0 will not be positioned. + + \sa Column, Row, Grid, Positioner, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty Transition QtQuick2::Flow::add + + This property holds the transition to be applied when adding an + item to the positioner. The transition will only be applied to the + added item(s). Positioner transitions will only affect the + position (x, y) of items. + + For a positioner, adding an item can mean that either the object + has been created or reparented, and thus is now a child or the + positioner, or that the object has had its opacity increased from + zero, and thus is now visible. + + \sa move +*/ +/*! + \qmlproperty Transition QtQuick2::Flow::move + + This property holds the transition to be applied when moving an + item within the positioner. Positioner transitions will only affect + the position (x, y) of items. + + This transition can be performed when other items are added or removed + from the positioner, or when items resize themselves. + + \qml + Flow { + id: positioner + move: Transition { + NumberAnimation { + properties: "x,y" + ease: "easeOutBounce" + } + } + } + \endqml + + \sa add, {declarative/positioners}{Positioners example} +*/ +/*! + \qmlproperty int QtQuick2::Flow::spacing + + spacing is the amount in pixels left empty between each adjacent + item, and defaults to 0. + + \sa Grid::spacing +*/ + class QSGFlowPrivate : public QSGBasePositionerPrivate { Q_DECLARE_PUBLIC(QSGFlow) @@ -661,6 +1335,21 @@ QSGFlow::QSGFlow(QSGItem *parent) d->addItemChangeListener(d, QSGItemPrivate::Geometry); } +/*! + \qmlproperty enumeration QtQuick2::Flow::flow + This property holds the flow of the layout. + + Possible values are: + + \list + \o Flow.LeftToRight (default) - Items are positioned next to + to each other according to the \l layoutDirection until the width of the Flow + is exceeded, then wrapped to the next line. + \o Flow.TopToBottom - Items are positioned next to each + other from top to bottom until the height of the Flow is exceeded, + then wrapped to the next column. + \endlist +*/ QSGFlow::Flow QSGFlow::flow() const { Q_D(const QSGFlow); @@ -677,6 +1366,25 @@ void QSGFlow::setFlow(Flow flow) } } +/*! + \qmlproperty enumeration QtQuick2::Flow::layoutDirection + + This property holds the layout direction of the layout. + + Possible values are: + + \list + \o Qt.LeftToRight (default) - Items are positioned from the top to bottom, + and left to right. The flow direction is dependent on the + \l Flow::flow property. + \o Qt.RightToLeft - Items are positioned from the top to bottom, + and right to left. The flow direction is dependent on the + \l Flow::flow property. + \endlist + + \sa Grid::layoutDirection, Row::layoutDirection, {declarative/righttoleft/layoutdirection}{Layout directions example} +*/ + Qt::LayoutDirection QSGFlow::layoutDirection() const { Q_D(const QSGFlow); @@ -694,6 +1402,17 @@ void QSGFlow::setLayoutDirection(Qt::LayoutDirection layoutDirection) } } +/*! + \qmlproperty enumeration QtQuick2::Flow::effectiveLayoutDirection + This property holds the effective layout direction of the flow positioner. + + When using the attached property \l {LayoutMirroring::enabled}{LayoutMirroring::enabled} for locale layouts, + the visual layout direction of the grid positioner will be mirrored. However, the + property \l {Flow::layoutDirection}{layoutDirection} will remain unchanged. + + \sa Flow::layoutDirection, {LayoutMirroring}{LayoutMirroring} +*/ + Qt::LayoutDirection QSGFlow::effectiveLayoutDirection() const { return QSGBasePositionerPrivate::getEffectiveLayoutDirection(this); |