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QListView Class

发布于 2019-10-04 15:01:08 字数 53223 浏览 972 评论 0 收藏 0

The QListView class implements a list/tree view. More...

#include <qlistview.h>

Inherits QScrollView.

List of all member functions.

Public Members

  • QListView ( QWidget*parent = 0, constchar*name = 0, WFlagsf = 0 )
  • ~QListView ()
  • int treeStepSize () const
  • virtual void setTreeStepSize ( int )
  • virtual void insertItem ( QListViewItem*i )
  • virtual void takeItem ( QListViewItem*i )
  • virtual void removeItem ( QListViewItem*item ) (obsolete)
  • QHeader * header () const
  • virtual int addColumn ( constQString&label, intwidth = -1 )
  • virtual int addColumn ( constQIconSet&iconset, constQString&label, intwidth = -1 )
  • virtual void removeColumn ( intindex )
  • virtual void setColumnText ( intcolumn, constQString&label )
  • virtual void setColumnText ( intcolumn, constQIconSet&iconset, constQString&label )
  • QString columnText ( intc ) const
  • virtual void setColumnWidth ( intcolumn, intw )
  • int columnWidth ( intc ) const
  • enum WidthMode { Manual, Maximum }
  • virtual void setColumnWidthMode ( intc, WidthModemode )
  • WidthMode columnWidthMode ( intc ) const
  • int columns () const
  • virtual void setColumnAlignment ( intcolumn, intalign )
  • int columnAlignment ( intcolumn ) const
  • QListViewItem * itemAt ( constQPoint&viewPos ) const
  • QRect itemRect ( constQListViewItem*i ) const
  • int itemPos ( constQListViewItem*item )
  • void ensureItemVisible ( constQListViewItem*i )
  • void repaintItem ( constQListViewItem*item ) const
  • virtual void setMultiSelection ( boolenable )
  • bool isMultiSelection () const
  • enum SelectionMode { Single, Multi, Extended, NoSelection }
  • void setSelectionMode ( SelectionModemode )
  • SelectionMode selectionMode () const
  • virtual void clearSelection ()
  • virtual void setSelected ( QListViewItem*item, boolselected )
  • bool isSelected ( constQListViewItem*i ) const
  • QListViewItem * selectedItem () const
  • virtual void setOpen ( QListViewItem*item, boolopen )
  • bool isOpen ( constQListViewItem*item ) const
  • virtual void setCurrentItem ( QListViewItem*i )
  • QListViewItem * currentItem () const
  • QListViewItem * firstChild () const
  • QListViewItem * lastItem () const
  • int childCount () const
  • virtual void setAllColumnsShowFocus ( bool )
  • bool allColumnsShowFocus () const
  • virtual void setItemMargin ( int )
  • int itemMargin () const
  • virtual void setRootIsDecorated ( bool )
  • bool rootIsDecorated () const
  • virtual void setSorting ( intcolumn, boolascending = TRUE )
  • virtual void sort ()
  • virtual bool eventFilter ( QObject*o, QEvent*e )
  • virtual void setShowSortIndicator ( boolshow )
  • bool showSortIndicator () const
  • virtual void setShowToolTips ( boolb )
  • bool showToolTips () const
  • enum ResizeMode { NoColumn, AllColumns, LastColumn }
  • virtual void setResizeMode ( ResizeModem )
  • ResizeMode resizeMode () const
  • QListViewItem * findItem ( constQString&text, intcolumn, ComparisonFlagscompare = ExactMatch | CaseSensitive ) const
  • enum RenameAction { Accept, Reject }
  • virtual void setDefaultRenameAction ( RenameActiona )
  • RenameAction defaultRenameAction () const
  • bool isRenaming () const

Public Slots

  • virtual void clear ()
  • virtual void invertSelection ()
  • virtual void selectAll ( boolselect )
  • void triggerUpdate ()

Signals

  • void selectionChanged ()
  • void selectionChanged ( QListViewItem * )
  • void currentChanged ( QListViewItem * )
  • void clicked ( QListViewItem*item )
  • void clicked ( QListViewItem*item, constQPoint&pnt, intc )
  • void pressed ( QListViewItem*item )
  • void pressed ( QListViewItem*item, constQPoint&pnt, intc )
  • void doubleClicked ( QListViewItem*item )
  • void returnPressed ( QListViewItem * )
  • void spacePressed ( QListViewItem * )
  • void rightButtonClicked ( QListViewItem *, const QPoint &, int )
  • void rightButtonPressed ( QListViewItem *, const QPoint &, int )
  • void mouseButtonPressed ( intbutton, QListViewItem*item, constQPoint&pos, intc )
  • void mouseButtonClicked ( intbutton, QListViewItem*item, constQPoint&pos, intc )
  • void contextMenuRequested ( QListViewItem*item, constQPoint&pos, intcol )
  • void onItem ( QListViewItem*i )
  • void onViewport ()
  • void expanded ( QListViewItem*item )
  • void collapsed ( QListViewItem*item )
  • void dropped ( QDropEvent*e )
  • void itemRenamed ( QListViewItem*item, intcol, constQString&text )
  • void itemRenamed ( QListViewItem*item, intcol )

Properties

  • bool allColumnsShowFocus- whether items should show keyboard focus using all columns
  • int childCount- the number of parentless (top level) QListViewItem objects in this QListView (read only)
  • int columns- the number of columns in this list view (read only)
  • RenameAction defaultRenameAction- whether the list view accepts the rename operation by default
  • int itemMargin- the advisory item margin that list items may use
  • bool multiSelection- whether the list view is in multi-selection or single selection mode
  • ResizeMode resizeMode- whether all, none or the last column should be resized
  • bool rootIsDecorated- whether the list view show open/close signs on root items
  • SelectionMode selectionMode- the list view's multi-selection mode
  • bool showSortIndicator- whether the list view header should display a sort indicator
  • bool showToolTips- whether this list view should show tooltips for truncated column texts
  • int treeStepSize- the number of pixels a child is offset from its parent

Protected Members

  • virtual void contentsMousePressEvent ( QMouseEvent*e )
  • virtual void contentsMouseReleaseEvent ( QMouseEvent*e )
  • virtual void contentsMouseMoveEvent ( QMouseEvent*e )
  • virtual void contentsMouseDoubleClickEvent ( QMouseEvent*e )
  • virtual QDragObject * dragObject ()
  • virtual void startDrag ()
  • virtual void resizeEvent ( QResizeEvent*e )
  • virtual void drawContentsOffset ( QPainter*p, intox, intoy, intcx, intcy, intcw, intch )
  • virtual void paintEmptyArea ( QPainter*p, constQRect&rect )

Protected Slots

  • void updateContents ()
  • void doAutoScroll ()

Detailed Description

The QListView class implements a list/tree view.

It can display and control a hierarchy of multi-column items, and provides the ability to add new items at any time. Among others the user may select one or many items and sort the list in increasing or decreasing order by any column.

The simplest mode of use is to create a QListView, add some column headers using addColumn() and create one or more QListViewItem or QCheckListItem objects with the QListView as parent:

        QListView * table;
        table->addColumn( "Qualified name" );
        table->addColumn( "Namespace" );
            element = new QListViewItem( table, qName, namespaceURI );

Further nodes can be added to the listview object (the root of the tree) or as child nodes to QListViewItems:

            for ( int i = 0 ; i < attributes.length(); i++ ) {
                new QListViewItem( element, attributes.qName(i), attributes.uri(i) );
            }

(From xml/tagreader-with-features/structureparser.cpp )

The main setup functions are

  • addColumn() - adds a column with text and perhaps width.

  • setColumnWidthMode() - sets the column to be resized automatically or not.

  • setAllColumnsShowFocus() - sets whether items should show keyboard focus using all columns or just column 0. The default is to show focus using just column 0.

  • setRootIsDecorated() - sets whether root items can be opened and closed by the user and have open/close decoration to their left. The default is FALSE.

  • setTreeStepSize() - sets how many pixels an item's children are indented relative to their parent. The default is 20. This is mostly a matter of taste.

  • setSorting() - sets whether the items should be sorted, whether it should be in ascending or descending order, and by what column it should be sorted. By default the list view is sorted by the first column; to switch this off call setSorting( -1 ).

To handle events such as mouse presses on the list view, derived classes can reimplement the QScrollView functions contentsMousePressEvent, contentsMouseReleaseEvent, contentsMouseDoubleClickEvent, contentsMouseMoveEvent, contentsDragEnterEvent, contentsDragMoveEvent, contentsDragLeaveEvent, contentsDropEvent, and contentsWheelEvent.

There are also several functions for mapping between items and coordinates. itemAt() returns the item at a position on-screen, itemRect() returns the rectangle an item occupies on the screen, and itemPos() returns the position of any item (not on-screen in the list view). firstChild() returns the item at the top of the view (not necessarily on-screen) so you can iterate over the items using either QListViewItem::itemBelow() or a combination of QListViewItem::firstChild() and QListViewItem::nextSibling().

If you need to move a list view item you can use takeItem() and insertItem(). Item's are deleted with delete; to delete all items use clear(). See the QListViewItem documentation for examples of traversal.

There are a variety of selection modes described in the QListView::SelectionMode documentation. The default is Single selection, which you can change using setSelectionMode().

Because QListView offers multiple selection it has to display keyboard focus and selection state separately. Therefore there are functions both to set the selection state of an item (setSelected()) and to select which item displays keyboard focus (setCurrentItem()).

QListView emits two groups of signals; one group signals changes in selection/focus state and one signals selection. The first group consists of selectionChanged() (applicable to all list views), selectionChanged( QListViewItem * ) (applicable only to Single selection list view), and currentChanged( QListViewItem * ). The second group consists of doubleClicked( QListViewItem * ), returnPressed( QListViewItem * ) and rightButtonClicked( QListViewItem *, const QPoint&, int ), etc.

In Motif style, QListView deviates fairly strongly from the look and feel of the Motif hierarchical tree view. This is done mostly to provide a usable keyboard interface and to make the list view look better with a white background.

If selectionMode() is Single (the default) the user can select one item at a time, e.g. by clicking an item with the mouse, see QListView::SelectionMode for details.

The listview can be navigated either using the mouse or the keyboard. Clicking an - icon closes an item (hides its children) and clicking an + icon opens an item (shows its children). The keyboard controls are these:

  • Home - Make the first item current and visible.
  • End - Make the last item current and visible.
  • Page Up - Make the item above the top visible item current and visible.
  • Page Down - Make the item below the bottom visible item current and visible.
  • Up Arrow - Make the item above the current item current and visible.
  • Down Arrow - Make the item below the current item current and visible.
  • Left Arrow - If the current item is closed (+ icon) or has no children make its parent item current and visible. If the current item is open (- icon) close it, i.e. hide its children. Exception: if the current item is the first item and is closed and the horizontal scrollbar is offset to the right the listview will be scrolled left.
  • Right Arrow - If the current item is closed (+ icon) and has children the item is opened. If the current item is opened (- icon) and has children the item's first child is made current and visible. If the current item has no children the listview is scrolled right.
If the user starts typing letters with the focus in the listview an incremental search will occur. For example if the user types 'd' the current item will change to the first item that begins with the letter 'd'; if they then type 'a', the current item will change to the first item that begins with 'da', and so on. If no item begins with the letters they type the current item doesn't change.

Warning: The list view assumes ownership of all list view items and will delete them when it does not need them any more.

See also QListViewItem, QCheckListItem and Advanced Widgets.


Member Type Documentation

QListView::RenameAction

This enum describes whether a rename operation is accepted if the rename editor loses focus without the user pressing Enter.

  • QListView::Accept - Rename if Enter is pressed or focus is lost.
  • QListView::Reject - Discard the rename operation if focus is lost (and Enter has not been pressed).

QListView::ResizeMode

This enum describes how the header adjusts to resize events which affect the width of the listview.

  • QListView::NoColumn - The columns do not get resized in resize events.
  • QListView::AllColumns - All columns are resized equally to fit the width of the listview.
  • QListView::LastColumn - The last columns is resized to fit the with of the listview.

QListView::SelectionMode

This enumerated type is used by QListView to indicate how it reacts to selection by the user. It has four values:

  • QListView::Single - When the user selects an item, any already-selected item becomes unselected, and the user cannot unselect the selected item. This means that the user can never clear the selection, even though the selection may be cleared by the application programmer using QListView::clearSelection().
  • QListView::Multi - When the user selects an item in the most ordinary way, the selection status of that item is toggled and the other items are left alone.
  • QListView::Extended - When the user selects an item in the most ordinary way, the selection is cleared and the new item selected. However, if the user presses the CTRL key when clicking on an item, the clicked item gets toggled and all other items are left untouched. And if the user presses the SHIFT key while clicking on an item, all items between the current item and the clicked item get selected or unselected, depending on the state of the clicked item. Also, multiple items can be selected by dragging the mouse while the left mouse button stays pressed.
  • QListView::NoSelection - Items cannot be selected.

In other words, Single is a real single-selection list view, Multi a real multi-selection list view, Extended is a list view where users can select multiple items but usually want to select either just one or a range of contiguous items, and NoSelection is a list view where the user can look but not touch.

QListView::WidthMode

This enum type describes how the width of a column in the view changes. The currently defined modes are:

  • QListView::Manual - the column width does not change automatically.
  • QListView::Maximum - the column is automatically sized according to the widths of all items in the column. (Note: The column never shrinks in this case.) This means the column is always resized to the width of the item with the largest width in the column.

See also setColumnWidth(), setColumnWidthMode() and columnWidth().


Member Function Documentation

QListView::QListView ( QWidget*parent = 0, constchar*name = 0, WFlagsf = 0 )

Constructs a new empty list view, with parent as a parent and name as object name.

Performance is boosted by modifying the widget flags f so that only part of the QListViewItem children is redrawn. This may be unsuitable for custom QListViewItem classes, in which case WStaticContents and WRepaintNoErase should be cleared.

See also QWidget::clearWFlags() and Qt::WidgetFlags.

QListView::~QListView ()

Destroys the list view, deleting all its items, and frees up all allocated resources.

int QListView::addColumn ( constQString&label, intwidth = -1 ) [virtual]

Adds a width pixels wide column with the column header label to this QListView, and returns the index of the new column.

All columns apart from the first one are inserted to the right of the existing ones.

If width is negative, the new column's WidthMode is set to Maximum instead of Manual.

See also setColumnText(), setColumnWidth() and setColumnWidthMode().

Examples: addressbook/centralwidget.cpp, checklists/checklists.cpp, dirview/main.cpp, fileiconview/mainwindow.cpp, listviews/listviews.cpp and qdir/qdir.cpp.

int QListView::addColumn ( constQIconSet&iconset, constQString&label, intwidth = -1 ) [virtual]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

Adds a width pixels wide new column with the header label and iconset to this QListView, and returns the index of the column.

If width is negative, the new column's WidthMode is set to Maximum, and to Manual otherwise.

See also setColumnText(), setColumnWidth() and setColumnWidthMode().

bool QListView::allColumnsShowFocus () const

Returns TRUE if items should show keyboard focus using all columns; otherwise returns FALSE. See the "allColumnsShowFocus" property for details.

int QListView::childCount () const

Returns the number of parentless (top level) QListViewItem objects in this QListView. See the "childCount" property for details.

void QListView::clear () [virtual slot]

Removes and deletes all the items in this list view and triggers an update.

See also triggerUpdate().

Examples: addressbook/centralwidget.cpp, checklists/checklists.cpp, listviews/listviews.cpp and network/ftpclient/ftpmainwindow.cpp.

void QListView::clearSelection () [virtual]

Sets all items to be not selected, updates the list view as necessary and emits the selectionChanged() signals. Note that for Multi selection list views this function needs to iterate over all items.

See also setSelected() and multiSelection.

Example: addressbook/centralwidget.cpp.

void QListView::clicked ( QListViewItem*item ) [signal]

This signal is emitted whenever the user clicks (mouse pressed and mouse released) in the list view. item is the pointer to the clicked list view item, or 0 if the user didn't click on an item.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

Example: addressbook/centralwidget.cpp.

void QListView::clicked ( QListViewItem*item, constQPoint&pnt, intc ) [signal]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

This signal is emitted whenever the user clicks (mouse pressed and mouse released) in the list view. item is the pointer to the clicked list view item, or 0 if the user didn't click on an item. pnt is the position where the user has clicked. If item is not 0, c is the list view column into which the user pressed; if item is 0 c's value is undefined.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

void QListView::collapsed ( QListViewItem*item ) [signal]

This signal is emitted when the item has been collapsed, i.e. when the children of item are hidden.

See also setOpen() and expanded().

int QListView::columnAlignment ( intcolumn ) const

Returns the alignment of column column. The default is AlignAuto.

See also Qt::AlignmentFlags.

QString QListView::columnText ( intc ) const

Returns the text of column c.

See also setColumnText().

int QListView::columnWidth ( intc ) const

Returns the width of column c.

See also setColumnWidth().

WidthMode QListView::columnWidthMode ( intc ) const

Returns the WidthMode for column c.

See also setColumnWidthMode().

int QListView::columns () const

Returns the number of columns in this list view. See the "columns" property for details.

void QListView::contentsMouseDoubleClickEvent ( QMouseEvent*e ) [virtual protected]

Processes the mouse double-click event e on behalf of the viewed widget.

Reimplemented from QScrollView.

void QListView::contentsMouseMoveEvent ( QMouseEvent*e ) [virtual protected]

Processes the mouse move event e on behalf of the viewed widget.

Example: dirview/dirview.cpp.

Reimplemented from QScrollView.

void QListView::contentsMousePressEvent ( QMouseEvent*e ) [virtual protected]

Processes the mouse move event e on behalf of the viewed widget.

Example: dirview/dirview.cpp.

Reimplemented from QScrollView.

void QListView::contentsMouseReleaseEvent ( QMouseEvent*e ) [virtual protected]

Processes the mouse move event e on behalf of the viewed widget.

Example: dirview/dirview.cpp.

Reimplemented from QScrollView.

void QListView::contextMenuRequested ( QListViewItem*item, constQPoint&pos, intcol ) [signal]

This signal is emitted when the user invokes a context menu with the right mouse button or with special system keys, with item being the item under the mouse cursor or the current item, respectively.

pos is the position for the context menu in the global coordinate system.

col is the column on which the user pressed, or -1 if the signal was triggered by a key event.

Example: listviews/listviews.cpp.

void QListView::currentChanged ( QListViewItem* ) [signal]

This signal is emitted whenever the current item has changed (normally after the screen update). The current item is the item responsible for indicating keyboard focus.

The argument is the newly current item, or 0 if the change was to make no item current. This can happen, for example, if all items in the list view are deleted.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

See also setCurrentItem() and currentItem().

Example: listviews/listviews.cpp.

QListViewItem* QListView::currentItem () const

Returns a pointer to the currently highlighted item, or 0 if there isn't one.

See also setCurrentItem().

Examples: addressbook/centralwidget.cpp and listviews/listviews.cpp.

RenameAction QListView::defaultRenameAction () const

Returns TRUE if the list view accepts the rename operation by default; otherwise returns FALSE. See the "defaultRenameAction" property for details.

void QListView::doAutoScroll () [protected slot]

This slot handles auto-scrolling when the mouse button is pressed and the mouse is outside the widget.

void QListView::doubleClicked ( QListViewItem*item ) [signal]

This signal is emitted whenever an item is double-clicked. It's emitted on the second button press, not the second button release. item is the list view item on which the user did the double-click.

QDragObject* QListView::dragObject () [virtual protected]

If the user presses the mouse on an item and starts moving the mouse, and the items allow dragging (see QListViewItem::setDragEnabled()), this function is called to get a drag object and a drag is started unless dragObject() returns 0.

By default this function returns 0. You should reimplement it and create a QDragObject depending on the selected items.

void QListView::drawContentsOffset ( QPainter*p, intox, intoy, intcx, intcy, intcw, intch ) [virtual protected]

Calls QListViewItem::paintCell() and/or QListViewItem::paintBranches() for all list view items that require repainting in the cw pixels wide and ch pixels high bounding rectangle starting at position cx, cy with offset ox, oy. Uses the painter p.

Reimplemented from QScrollView.

void QListView::dropped ( QDropEvent*e ) [signal]

This signal is emitted, when a drop event occurred onto the viewport (not onto an item).

e gives you all information about the drop.

void QListView::ensureItemVisible ( constQListViewItem*i )

Ensures that item i is made visible, scrolling the list view vertically as required and also opening (expanding) any parent items if this is necessary to show the item.

See also itemRect() and QScrollView::ensureVisible().

bool QListView::eventFilter ( QObject*o, QEvent*e ) [virtual]

Redirects the event e relating to object o, for the viewport to mousePressEvent(), keyPressEvent() and friends.

Reimplemented from QScrollView.

void QListView::expanded ( QListViewItem*item ) [signal]

This signal is emitted when item has been expanded, i.e. when the children of item are shown.

See also setOpen() and collapsed().

QListViewItem* QListView::findItem ( constQString&text, intcolumn, ComparisonFlagscompare = ExactMatch | CaseSensitive ) const

Finds the first list view item in column column, that matches text and returns the item, or returns 0 of no such item could be found. Pass OR-ed together Qt::StringComparisonMode values in the compare flag, to control how the matching is performed. The default comparison mode is case-sensitive, exact match.

QListViewItem* QListView::firstChild () const

Returns the first item in this QListView. You can use its firstChild() and nextSibling() functions to traverse the entire tree of items.

Returns 0 if there is no first item.

See also itemAt(), QListViewItem::itemBelow() and QListViewItem::itemAbove().

Examples: addressbook/centralwidget.cpp and listviews/listviews.cpp.

QHeader* QListView::header () const

Returns a pointer to the QHeader object that manages this list view's columns. Please don't modify the header behind the list view's back.

You may safely call QHeader::setClickEnabled(), QHeader::setResizeEnabled(), QHeader::setMovingEnabled() and all the const QHeader functions.

Examples: listviews/listviews.cpp and qdir/qdir.cpp.

void QListView::insertItem ( QListViewItem*i ) [virtual]

Inserts item i into the list view as a top-level item. You do not need to call this unless you've called takeItem(i) or QListViewItem::takeItem(i) and need to reinsert i elsewhere.

See also QListViewItem::takeItem() and takeItem().

void QListView::invertSelection () [virtual slot]

Inverts the selection. Works only in Multi and Extended selection mode.

bool QListView::isMultiSelection () const

Returns TRUE if the list view is in multi-selection or single selection mode; otherwise returns FALSE. See the "multiSelection" property for details.

bool QListView::isOpen ( constQListViewItem*item ) const

Identical to item->isOpen(). Provided for completeness.

See also setOpen().

bool QListView::isRenaming () const

Returns whether currently an item of the listview is being renamed

bool QListView::isSelected ( constQListViewItem*i ) const

Returns TRUE if the list view item i is selected; otherwise returns FALSE.

See also QListViewItem::isSelected().

QListViewItem* QListView::itemAt ( constQPoint&viewPos ) const

Returns a pointer to the QListViewItem at viewPos. Note that viewPos is in the coordinate system of viewport(), not in the list view's own, much larger, coordinate system.

itemAt() returns 0 if there is no such item.

Note that you also get the pointer to the item if viewPos points to the root decoration (see setRootIsDecorated()) of the item. To check whether or not viewPos is on the root decoration of the item, you can do something like this:

  QListViewItem *i = itemAt( p );
  if ( i ) {
      if ( p.x() > header()->cellPos( header()->mapToActual( 0 ) ) +
             treeStepSize() * ( i->depth() + ( rootIsDecorated() ? 1 : 0) ) + itemMargin() ||
             p.x() < header()->cellPos( header()->mapToActual( 0 ) ) ) {
          ; // p is not on root decoration
      else
          ; // p is on the root decoration
  }
  

This might be interesting if you use this function to find out where the user clicked and if you want to start a drag (which you do not want to do if the user clicked onto the root decoration of an item).

See also itemPos() and itemRect().

int QListView::itemMargin () const

Returns the advisory item margin that list items may use. See the "itemMargin" property for details.

int QListView::itemPos ( constQListViewItem*item )

Returns the y-coordinate of item in the list view's coordinate system. This function is normally much slower than itemAt() but it works for all items, whereas itemAt() normally works only for items on the screen.

This is a thin wrapper around QListViewItem::itemPos().

See also itemAt() and itemRect().

QRect QListView::itemRect ( constQListViewItem*i ) const

Returns the rectangle on the screen that item i occupies in viewport()'s coordinates, or an invalid rectangle if i is a null pointer or is not currently visible.

The rectangle returned does not include any children of the rectangle (i.e. it uses QListViewItem::height(), rather than QListViewItem::totalHeight()). If you want the rectangle to include children you can use something like this:

    QRect r( listView->itemRect( item ) );
    r.setHeight( (QCOORD)(QMIN( item->totalHeight(),
                                listView->viewport->height() - r.y() ) ) )
  

Note the way it avoids too-high rectangles. totalHeight() can be much larger than the window system's coordinate system allows.

itemRect() is comparatively slow. It's best to call it only for items that are probably on-screen.

void QListView::itemRenamed ( QListViewItem*item, intcol, constQString&text ) [signal]

This signal is emitted when item has been renamed to text, e.g. by in in-place renaming, in column col.

void QListView::itemRenamed ( QListViewItem*item, intcol ) [signal]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

This signal is emitted when item has been renamed, e.g. by in-place renaming, in column col.

QListViewItem* QListView::lastItem () const

Returns the last item in the list view tree.

Returns 0 if there are no items in the QListView.

This function is slow.

void QListView::mouseButtonClicked ( intbutton, QListViewItem*item, constQPoint&pos, intc ) [signal]

This signal is emitted whenever the user clicks (mouse pressed and mouse released) in the list view at position pos. button is the mouse button that the user pressed, item is the pointer to the clicked list view item or 0 if the user didn't click on an item. If item is not 0, c is the list view column into which the user pressed; if item is 0 c's value is undefined.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

void QListView::mouseButtonPressed ( intbutton, QListViewItem*item, constQPoint&pos, intc ) [signal]

This signal is emitted whenever the user pressed the mouse button in the list view at position pos. button is the mouse button which the user pressed, item is the pointer to the pressed list view item or 0 if the user didn't press on an item. If item is not 0, c is the list view column into which the user pressed; if item is 0 c's value is undefined.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

void QListView::onItem ( QListViewItem*i ) [signal]

This signal is emitted when the user moves the mouse cursor onto the item i, similar to the QWidget::enterEvent() function.

void QListView::onViewport () [signal]

This signal is emitted when the user moves the mouse cursor from an item to an empty part of the list view.

void QListView::paintEmptyArea ( QPainter*p, constQRect&rect ) [virtual protected]

Paints rect so that it looks like empty background using painter p. rect is is widget coordinates, ready to be fed to p.

The default function fills rect with the viewport()->backgroundBrush()

void QListView::pressed ( QListViewItem*item ) [signal]

This signal is emitted whenever the user presses the mouse button in a list view. item is the pointer to the list view item on which the user pressed the mouse button, or 0 if the user didn't press the mouse on an item.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

void QListView::pressed ( QListViewItem*item, constQPoint&pnt, intc ) [signal]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

This signal is emitted whenever the user presses the mouse button in a list view. item is the pointer to the list view item on which the user pressed the mouse button, or 0 if the user didn't press the mouse on an item. pnt is the position of the mouse cursor, and c is the column where the mouse cursor was when the user pressed the mouse button.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

void QListView::removeColumn ( intindex ) [virtual]

Removes the column at position index.

void QListView::removeItem ( QListViewItem*item ) [virtual]

This function is obsolete. It is provided to keep old source working. We strongly advise against using it in new code.

This function has been renamed takeItem().

void QListView::repaintItem ( constQListViewItem*item ) const

Repaints item on the screen if item is currently visible. Takes care to avoid multiple repaints.

void QListView::resizeEvent ( QResizeEvent*e ) [virtual protected]

Ensures that the header is correctly sized and positioned when the resize event e occurs.

ResizeMode QListView::resizeMode () const

Returns TRUE if all, none or the last column should be resized; otherwise returns FALSE. See the "resizeMode" property for details.

void QListView::returnPressed ( QListViewItem* ) [signal]

This signal is emitted when Enter or Return is pressed. The argument is the currentItem().

void QListView::rightButtonClicked ( QListViewItem*, constQPoint&, int ) [signal]

This signal is emitted when the right button is clicked (i.e. when it's released). The arguments are the relevant QListViewItem (may be 0), the point in global coordinates and the relevant column (or -1 if the click was outside the list).

void QListView::rightButtonPressed ( QListViewItem*, constQPoint&, int ) [signal]

This signal is emitted when the right button is pressed. Arguments are then the relevant QListViewItem (may be 0), the point in global coordinates and the relevant column (or -1 if the click was outside the list).

bool QListView::rootIsDecorated () const

Returns TRUE if the list view show open/close signs on root items; otherwise returns FALSE. See the "rootIsDecorated" property for details.

void QListView::selectAll ( boolselect ) [virtual slot]

If select is TRUE, all items get selected; otherwise all items get unselected. This works only in the selection modes Multi and Extended. In Single and NoSelection mode the selection of the current item is just set to select.

QListViewItem* QListView::selectedItem () const

Returns a pointer to the selected item if the list view is in single-selection mode and an item is selected.

If no items are selected or the list view is in multi-selection mode this function returns 0.

See also setSelected() and multiSelection.

void QListView::selectionChanged () [signal]

This signal is emitted whenever the set of selected items has changed (normally before the screen update). It is available both in Single selection and Multi selection mode but is most useful in Multi selection mode.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

See also setSelected() and QListViewItem::setSelected().

Example: listviews/listviews.cpp.

void QListView::selectionChanged ( QListViewItem* ) [signal]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

This signal is emitted whenever the selected item has changed in Single selection mode (normally after the screen update). The argument is the newly selected item.

The no argument overload of this signal is more useful in Multi selection mode.

Note that you may not delete any QListViewItem objects in slots connected to this signal.

See also setSelected(), QListViewItem::setSelected() and currentChanged().

SelectionMode QListView::selectionMode () const

Returns the list view's multi-selection mode. See the "selectionMode" property for details.

void QListView::setAllColumnsShowFocus ( bool ) [virtual]

Sets whether items should show keyboard focus using all columns. See the "allColumnsShowFocus" property for details.

void QListView::setColumnAlignment ( intcolumn, intalign ) [virtual]

Sets column column's alignment to align. The alignment is ultimately passed to QListViewItem::paintCell() for each item in the view.

See also Qt::AlignmentFlags.

Example: listviews/listviews.cpp.

void QListView::setColumnText ( intcolumn, constQString&label ) [virtual]

Sets the heading of column column to label. The leftmost column is 0.

See also columnText().

void QListView::setColumnText ( intcolumn, constQIconSet&iconset, constQString&label ) [virtual]

This is an overloaded member function, provided for convenience. It behaves essentially like the above function.

Sets the heading of column column to iconset and label. The leftmost column is 0.

See also columnText().

void QListView::setColumnWidth ( intcolumn, intw ) [virtual]

Sets the width of column column to w pixels. Note that if the column has a WidthMode other than Manual, this width setting may be subsequently overridden. The leftmost column is 0.

See also columnWidth().

void QListView::setColumnWidthMode ( intc, WidthModemode ) [virtual]

Sets column c's width mode to mode. The default depends on whether the width argument to addColumn was positive or negative.

See also QListViewItem::width().

void QListView::setCurrentItem ( QListViewItem*i ) [virtual]

Sets item i to be the current highlighted item and repaints appropriately. This highlighted item is used for keyboard navigation and focus indication; it doesn't mean anything else, e.g. it is different from selection.

See also currentItem() and setSelected().

Example: listviews/listviews.cpp.

void QListView::setDefaultRenameAction ( RenameActiona ) [virtual]

Sets whether the list view accepts the rename operation by default to a. See the "defaultRenameAction" property for details.

void QListView::setItemMargin ( int ) [virtual]

Sets the advisory item margin that list items may use. See the "itemMargin" property for details.

void QListView::setMultiSelection ( boolenable ) [virtual]

Sets whether the list view is in multi-selection or single selection mode to enable. See the "multiSelection" property for details.

void QListView::setOpen ( QListViewItem*item, boolopen ) [virtual]

Sets item to be open if open is TRUE and item is expandable, and to be closed if open is FALSE. Repaints accordingly.

See also QListViewItem::setOpen() and QListViewItem::setExpandable().

void QListView::setResizeMode ( ResizeModem ) [virtual]

Sets whether all, none or the last column should be resized to m. See the "resizeMode" property for details.

void QListView::setRootIsDecorated ( bool ) [virtual]

Sets whether the list view show open/close signs on root items. See the "rootIsDecorated" property for details.

void QListView::setSelected ( QListViewItem*item, boolselected ) [virtual]

If selected is TRUE the item is selected; otherwise it is unselected.

If the list view is in Single selection mode and selected is TRUE, the currently selected item is unselected and item is made current. Unlike QListViewItem::setSelected(), this function updates the list view as necessary and emits the selectionChanged() signals.

See also isSelected(), multiSelection, multiSelection and setCurrentItem().

Example: listviews/listviews.cpp.

void QListView::setSelectionMode ( SelectionModemode )

Sets the list view's multi-selection mode to mode. See the "selectionMode" property for details.

void QListView::setShowSortIndicator ( boolshow ) [virtual]

Sets whether the list view header should display a sort indicator to show. See the "showSortIndicator" property for details.

void QListView::setShowToolTips ( boolb ) [virtual]

Sets whether this list view should show tooltips for truncated column texts to b. See the "showToolTips" property for details.

void QListView::setSorting ( intcolumn, boolascending = TRUE ) [virtual]

Sets the list view to be sorted by column and in ascending order if ascending is TRUE or descending order if it is FALSE.

If column is -1, sorting is disabled and the user cannot sort columns by clicking on the column headers. If column is larger than the number of columns the user has to click on a column header to sort the list view.

void QListView::setTreeStepSize ( int ) [virtual]

Sets the number of pixels a child is offset from its parent. See the "treeStepSize" property for details.

bool QListView::showSortIndicator () const

Returns TRUE if the list view header should display a sort indicator; otherwise returns FALSE. See the "showSortIndicator" property for details.

bool QListView::showToolTips () const

Returns TRUE if this list view should show tooltips for truncated column texts; otherwise returns FALSE. See the "showToolTips" property for details.

void QListView::sort () [virtual]

(Re)sorts the list view using the last sorting configuration (sort column and ascending/descending).

void QListView::spacePressed ( QListViewItem* ) [signal]

This signal is emitted when Space is pressed. The argument is currentItem().

void QListView::startDrag () [virtual protected]

Starts a drag.

void QListView::takeItem ( QListViewItem*i ) [virtual]

Removes item i from the list view; i must be a top-level item. The warnings regarding QListViewItem::takeItem() apply to this function, too.

See also insertItem().

int QListView::treeStepSize () const

Returns the number of pixels a child is offset from its parent. See the "treeStepSize" property for details.

void QListView::triggerUpdate () [slot]

Triggers a size, geometry and content update during the next iteration of the event loop. Ensures that there'll be just one update to avoid flicker.

void QListView::updateContents () [protected slot]

Updates the sizes of the viewport, header, scroll bars and so on. Don't call this directly; call triggerUpdate() instead.

Property Documentation

bool allColumnsShowFocus

This property holds whether items should show keyboard focus using all columns.

If this property is TRUE all columns will show focus and selection states, otherwise only column 0 will show focus.

The default is FALSE.

Setting this to TRUE if it's not necessary may cause noticeable flicker.

Set this property's value with setAllColumnsShowFocus() and get this property's value with allColumnsShowFocus().

int childCount

This property holds the number of parentless (top level) QListViewItem objects in this QListView.

Represents the current number of parentless (top level) QListViewItem objects in this QListView, like QListViewItem::childCount() returns the number of child items for a QListViewItem.

See also QListViewItem::childCount().

Get this property's value with childCount().

int columns

This property holds the number of columns in this list view.

Get this property's value with columns().

See also addColumn() and removeColumn().

RenameAction defaultRenameAction

This property holds whether the list view accepts the rename operation by default.

If this property is Accept, and the user renames an item and the editor looses focus (without the user pressing Enter), the item will still be renamed. If the property's value is Reject, the item will not be renamed unless the user presses Enter. The default is Reject.

Set this property's value with setDefaultRenameAction() and get this property's value with defaultRenameAction().

int itemMargin

This property holds the advisory item margin that list items may use.

The item margin defaults to one pixel and is the margin between the item's edges and the area where it draws its contents. QListViewItem::paintFocus() draws in the margin.

See also QListViewItem::paintCell().

Set this property's value with setItemMargin() and get this property's value with itemMargin().

bool multiSelection

This property holds whether the list view is in multi-selection or single selection mode.

If you enable multi-selection mode, it is possible to specify whether or not this mode should be extended. Extended means that the user can select multiple items only when pressing the Shift or Ctrl key at the same time.

The default selection mode is Single.

See also selectionMode.

Set this property's value with setMultiSelection() and get this property's value with isMultiSelection().

ResizeMode resizeMode

This property holds whether all, none or the last column should be resized.

Specifies whether all, none or the last column should be resized to fit the full width of the listview. The values for this property can be one of the following: NoColumn (the default), AllColumns or LastColumn.

See also QHeader and header().

Set this property's value with setResizeMode() and get this property's value with resizeMode().

bool rootIsDecorated

This property holds whether the list view show open/close signs on root items.

Open/close signs are small + or - symbols in windows style, or arrows in Motif style. The default is FALSE.

Set this property's value with setRootIsDecorated() and get this property's value with rootIsDecorated().

SelectionMode selectionMode

This property holds the list view's multi-selection mode.

The mode can be Single (the default), Extended, Multi or NoSelection.

See also multiSelection.

Set this property's value with setSelectionMode() and get this property's value with selectionMode().

bool showSortIndicator

This property holds whether the list view header should display a sort indicator.

If this property is TRUE, an arrow is drawn in the header of the list view to indicate the sort order of the list view contents. The arrow will be drawn in the correct column and will point up or down, depending on the current sort direction. The default is FALSE (don't show an indicator).

See also QHeader::setSortIndicator().

Set this property's value with setShowSortIndicator() and get this property's value with showSortIndicator().

bool showToolTips

This property holds whether this list view should show tooltips for truncated column texts.

The default is TRUE.

Set this property's value with setShowToolTips() and get this property's value with showToolTips().

int treeStepSize

This property holds the number of pixels a child is offset from its parent.

The default is 20 pixels.

Of course, this property is only meaningful for hierarchical list views.

Set this property's value with setTreeStepSize() and get this property's value with treeStepSize().

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