|  | Home · All Namespaces · All Classes · Main Classes · Grouped Classes · Modules · Functions |

# Q3ListView Class Reference
[Qt3Support module]

The Q3ListView class implements a list/tree view. More...

     #include <Q3ListView>

This class is part of the Qt 3 support library. It is provided to keep old source code working. We strongly advise against using it in new code. See Porting to Qt 4 for more information.

Inherits Q3ScrollView.

- List of all members, including inherited members

### Public Types

- typedef ComparisonFlags
- enum RenameAction { Accept, Reject }
- enum ResizeMode { NoColumn, AllColumns, LastColumn }
- enum SelectionMode { Single, Multi, Extended, NoSelection }
- enum StringComparisonMode { CaseSensitive, ExactMatch, BeginsWith, EndsWith, Contains }
- enum WidthMode { Manual, Maximum }

### Properties

allColumnsShowFocus : bool childCount : const int columns : const int defaultRenameAction : RenameAction itemMargin : int multiSelection : bool | resizeMode : ResizeMode rootIsDecorated : bool selectionMode : SelectionMode showSortIndicator : bool showToolTips : bool treeStepSize : int

- 10 properties inherited from Q3ScrollView
- 2 properties inherited from Q3Frame
- 6 properties inherited from QFrame
- 57 properties inherited from QWidget
- 1 property inherited from QObject

### Public Functions

- Q3ListView ( QWidget * parent = 0, const char * name = 0, Qt::WindowFlags f = 0 )
- ~Q3ListView ()
- virtual int addColumn ( const QString & label, int width = -1 )
- virtual int addColumn ( const QIcon & icon, const QString & label, int width = -1 )
- bool allColumnsShowFocus () const
- int childCount () const
- virtual void clearSelection ()
- int columnAlignment ( int column ) const
- QString columnText ( int c ) const
- int columnWidth ( int c ) const
- WidthMode columnWidthMode ( int c ) const
- int columns () const
- Q3ListViewItem * currentItem () const
- RenameAction defaultRenameAction () const
- void ensureItemVisible ( const Q3ListViewItem * i )
- virtual bool eventFilter ( QObject * o, QEvent * e )
- Q3ListViewItem * findItem ( const QString & text, int column, ComparisonFlags compare = ExactMatch | Qt::CaseSensitive ) const
- Q3ListViewItem * firstChild () const
- Q3Header * header () const
- void hideColumn ( int column )
- virtual void insertItem ( Q3ListViewItem * i )
- bool isMultiSelection () const
- bool isOpen ( const Q3ListViewItem * item ) const
- bool isRenaming () const
- bool isSelected ( const Q3ListViewItem * i ) const
- Q3ListViewItem * itemAt ( const QPoint & viewPos ) const
- int itemMargin () const
- int itemPos ( const Q3ListViewItem * item )
- QRect itemRect ( const Q3ListViewItem * item ) const
- Q3ListViewItem * lastItem () const
- virtual void removeColumn ( int index )
- virtual void removeItem ( Q3ListViewItem * item )
- void repaintItem ( const Q3ListViewItem * item ) const
- ResizeMode resizeMode () const
- bool rootIsDecorated () const
- Q3ListViewItem * selectedItem () const
- SelectionMode selectionMode () const
- virtual void setAllColumnsShowFocus ( bool )
- virtual void setColumnAlignment ( int column, int align )
- virtual void setColumnText ( int column, const QString & label )
- virtual void setColumnText ( int column, const QIcon & icon, const QString & label )
- virtual void setColumnWidth ( int column, int w )
- virtual void setColumnWidthMode ( int c, WidthMode mode )
- virtual void setCurrentItem ( Q3ListViewItem * i )
- virtual void setDefaultRenameAction ( RenameAction a )
- virtual void setItemMargin ( int )
- virtual void setMultiSelection ( bool enable )
- virtual void setOpen ( Q3ListViewItem * item, bool open )
- virtual void setResizeMode ( ResizeMode m )
- virtual void setRootIsDecorated ( bool )
- virtual void setSelected ( Q3ListViewItem * item, bool selected )
- void setSelectionAnchor ( Q3ListViewItem * item )
- void setSelectionMode ( SelectionMode mode )
- virtual void setShowSortIndicator ( bool show )
- virtual void setShowToolTips ( bool b )
- void setSortColumn ( int column )
- void setSortOrder ( Qt::SortOrder order )
- virtual void setSorting ( int column, bool ascending = true )
- virtual void setTreeStepSize ( int )
- bool showSortIndicator () const
- bool showToolTips () const
- virtual void sort ()
- int sortColumn () const
- Qt::SortOrder sortOrder () const
- virtual void takeItem ( Q3ListViewItem * i )
- int treeStepSize () const

- 46 public functions inherited from Q3ScrollView
- 4 public functions inherited from Q3Frame
- 13 public functions inherited from QFrame
- 206 public functions inherited from QWidget
- 29 public functions inherited from QObject
- 14 public functions inherited from QPaintDevice

### Public Slots

- void adjustColumn ( int col )
- virtual void clear ()
- virtual void invertSelection ()
- virtual void selectAll ( bool select )
- void triggerUpdate ()

- 8 public slots inherited from Q3ScrollView
- 19 public slots inherited from QWidget
- 1 public slot inherited from QObject

### Signals

- void clicked ( Q3ListViewItem * item )
- void clicked ( Q3ListViewItem * item, const QPoint & pnt, int c )
- void collapsed ( Q3ListViewItem * item )
- void contextMenuRequested ( Q3ListViewItem * item, const QPoint & pos, int col )
- void currentChanged ( Q3ListViewItem * item )
- void doubleClicked ( Q3ListViewItem * item )
- void doubleClicked ( Q3ListViewItem * item, const QPoint & point, int column )
- void dropped ( QDropEvent * e )
- void expanded ( Q3ListViewItem * item )
- void itemRenamed ( Q3ListViewItem * item, int col, const QString & text )
- void itemRenamed ( Q3ListViewItem * item, int col )
- void mouseButtonClicked ( int button, Q3ListViewItem * item, const QPoint & pos, int c )
- void mouseButtonPressed ( int button, Q3ListViewItem * item, const QPoint & pos, int c )
- void onItem ( Q3ListViewItem * i )
- void onViewport ()
- void pressed ( Q3ListViewItem * item )
- void pressed ( Q3ListViewItem * item, const QPoint & pnt, int c )
- void returnPressed ( Q3ListViewItem * item )
- void rightButtonClicked ( Q3ListViewItem * item, const QPoint & point, int column )
- void rightButtonPressed ( Q3ListViewItem * item, const QPoint & point, int column )
- void selectionChanged ()
- void selectionChanged ( Q3ListViewItem * item )
- void spacePressed ( Q3ListViewItem * item )

- 5 signals inherited from Q3ScrollView
- 1 signal inherited from QWidget
- 1 signal inherited from QObject

### Protected Functions

- virtual void contentsMouseDoubleClickEvent ( QMouseEvent * e )
- virtual void contentsMouseMoveEvent ( QMouseEvent * e )
- virtual void contentsMousePressEvent ( QMouseEvent * e )
- virtual void contentsMouseReleaseEvent ( QMouseEvent * e )
- virtual Q3DragObject * dragObject ()
- virtual void drawContentsOffset ( QPainter * p, int ox, int oy, int cx, int cy, int cw, int ch )
- virtual void paintEmptyArea ( QPainter * p, const QRect & rect )
- virtual void resizeEvent ( QResizeEvent * e )
- virtual void startDrag ()

- 17 protected functions inherited from Q3ScrollView
- 5 protected functions inherited from Q3Frame
- 38 protected functions inherited from QWidget
- 7 protected functions inherited from QObject
- 1 protected function inherited from QPaintDevice

### Protected Slots

- void doAutoScroll ()
- void updateContents ()

- 1 protected slot inherited from QWidget

### Additional Inherited Members

- 4 static public members inherited from QWidget
- 5 static public members inherited from QObject
- 1 static public member inherited from QPaintDevice

## Detailed Description

The Q3ListView 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. The user may select one or many items (depending on the `SelectionMode`) and sort the list in increasing or decreasing order by any column.

The simplest pattern of use is to create a Q3ListView, add some column headers using addColumn() and create one or more Q3ListViewItem or Q3CheckListItem objects with the Q3ListView as parent.

Further nodes can be added to the list view object (the root of the tree) or as child nodes to Q3ListViewItems.

The main setup functions are:

Function | Action
--- | ---
addColumn() | Adds a column with a text label and perhaps width. Columns are counted from the left starting with column 0.
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 just using 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 they should be sorted. By default the list view is sorted by the first column; to switch this off call setSorting(-1).

There are 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 (whether it is on-screen or not). firstChild() returns the list view's first item (not necessarily visible on-screen).

You can iterate over visible items using Q3ListViewItem::itemBelow(); over a list view's top-level items using Q3ListViewItem::firstChild() and Q3ListViewItem::nextSibling(); or every item using a Q3ListViewItemIterator. See the Q3ListViewItem documentation for examples of traversal.

An item can be moved amongst its siblings using Q3ListViewItem::moveItem(). To move an item in the hierarchy use takeItem() and insertItem(). Item's (and all their child items) are deleted with `delete`; to delete all the list view's items use clear().

There are a variety of selection modes described in the Q3ListView::SelectionMode documentation. The default is `Single` selection, which you can change using setSelectionMode().

Because Q3ListView offers multiple selection it must display keyboard focus and selection state separately. Therefore there are functions both to set the selection state of an item (setSelected()) and to set which item displays keyboard focus (setCurrentItem()).

Q3ListView emits two groups of signals; one group signals changes in selection/focus state and one indicates selection. The first group consists of selectionChanged() (applicable to all list views), selectionChanged(Q3ListViewItem*) (applicable only to a `Single` selection list view), and currentChanged(Q3ListViewItem*). The second group consists of doubleClicked(Q3ListViewItem*), returnPressed(Q3ListViewItem*), rightButtonClicked(Q3ListViewItem*, const QPoint&, int), etc.

Note that changing the state of the list view in a slot connected to a list view signal may cause unexpected side effects. If you need to change the list view's state in response to a signal, use a single shot timer with a time out of 0, and connect this timer to a slot that modifies the list view's state.

In Motif style, Q3ListView 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 Q3ListView::SelectionMode for details.

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

Keypress | Action
--- | ---
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 scroll bar is offset to the right the list view 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 list view is scrolled right.

If the user starts typing letters with the focus in the list view 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.

Note that the list view's size hint is calculated taking into account the height and width to produce a nice aspect ratio. This may mean that you need to reimplement sizeHint() in some cases.

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 Q3ListViewItem and Q3CheckListItem.

## Member Type Documentation

### typedef Q3ListView::ComparisonFlags

This typedef is used in Q3ListView's API for values that are OR'd combinations of StringComparisonMode values.

See also StringComparisonMode.

### enum Q3ListView::RenameAction

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

Constant | Value | Description
--- | --- | ---
`Q3ListView::Accept` | `0` | Rename if Enter is pressed or focus is lost.
`Q3ListView::Reject` | `1` | Discard the rename operation if focus is lost (and Enter has not been pressed).

### enum Q3ListView::ResizeMode

This enum describes how the list view's header adjusts to resize events which affect the width of the list view.

Constant | Value | Description
--- | --- | ---
`Q3ListView::NoColumn` | `0` | The columns do not get resized in resize events.
`Q3ListView::AllColumns` | `1` | All columns are resized equally to fit the width of the list view.
`Q3ListView::LastColumn` | `2` | The last column is resized to fit the width of the list view.

### enum Q3ListView::SelectionMode

This enumerated type is used by Q3ListView to indicate how it reacts to selection by the user.

Constant | Value | Description
--- | --- | ---
`Q3ListView::Single` | `0` | When the user selects an item, any already-selected item becomes unselected, and the user cannot unselect the selected item.
`Q3ListView::Multi` | `1` | When the user selects an item in the usual way, the selection status of that item is toggled and the other items are left alone.
`Q3ListView::Extended` | `2` | When the user selects an item in the usual 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 over them.
`Q3ListView::NoSelection` | `3` | 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.

### enum Q3ListView::StringComparisonMode

This enum type is used to set the string comparison mode when searching for an item. We'll refer to the string being searched as the 'target' string.

Constant | Value | Description
--- | --- | ---
`Q3ListView::CaseSensitive` | `0x00001` | The strings must match case sensitively.
`Q3ListView::ExactMatch` | `0x00010` | The target and search strings must match exactly.
`Q3ListView::BeginsWith` | `0x00002` | The target string begins with the search string.
`Q3ListView::EndsWith` | `0x00004` | The target string ends with the search string.
`Q3ListView::Contains` | `0x00008` | The target string contains the search string.

If you OR these flags together (excluding `CaseSensitive`), the search criteria be applied in the following order: `ExactMatch`, `BeginsWith`, `EndsWith`, `Contains`.

Matching is case-insensitive unless `CaseSensitive` is set. `CaseSensitive` can be OR-ed with any combination of the other flags.

See also ComparisonFlags.

### enum Q3ListView::WidthMode

This enum type describes how the width of a column in the view changes.

Constant | Value | Description
--- | --- | ---
`Q3ListView::Manual` | `0` | the column width does not change automatically.
`Q3ListView::Maximum` | `1` | 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 that the column is always resized to the width of the item with the largest width in the column.

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

## Property Documentation

### allColumnsShowFocus : bool

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.

Access functions:

- bool allColumnsShowFocus () const
- virtual void setAllColumnsShowFocus ( bool )

### childCount : const int

This property holds the number of parentless (top-level) Q3ListViewItem objects in this Q3ListView.

Holds the current number of parentless (top-level) Q3ListViewItem objects in this Q3ListView.

Access functions:

- int childCount () const

See also Q3ListViewItem::childCount().

### columns : const int

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

Access functions:

- int columns () const

See also addColumn() and removeColumn().

### defaultRenameAction : RenameAction

This property holds what action to perform when the editor loses focus during renaming.

If this property is `Accept`, and the user renames an item and the editor loses 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`.

Access functions:

- RenameAction defaultRenameAction () const
- virtual void setDefaultRenameAction ( RenameAction a )

### itemMargin : int

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. Q3ListViewItem::paintFocus() draws in the margin.

Access functions:

- int itemMargin () const
- virtual void setItemMargin ( int )

See also Q3ListViewItem::paintCell().

### multiSelection : bool

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

If you enable multi-selection, `Multi`, 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`.

Access functions:

- bool isMultiSelection () const
- virtual void setMultiSelection ( bool enable )

See also selectionMode().

### resizeMode : ResizeMode

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

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

Warning: Setting the resize mode should be done after all necessary columns have been added to the list view, otherwise the behavior is undefined.

Access functions:

- ResizeMode resizeMode () const
- virtual void setResizeMode ( ResizeMode m )

See also Q3Header and header().

### rootIsDecorated : bool

This property holds whether the list view shows 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.

Access functions:

- bool rootIsDecorated () const
- virtual void setRootIsDecorated ( bool )

### selectionMode : SelectionMode

This property holds the list view's selection mode.

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

Access functions:

- SelectionMode selectionMode () const
- void setSelectionMode ( SelectionMode mode )

See also multiSelection.

### showSortIndicator : bool

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).

Access functions:

- bool showSortIndicator () const
- virtual void setShowSortIndicator ( bool show )

See also Q3Header::setSortIndicator().

### showToolTips : bool

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

The default is true.

Access functions:

- bool showToolTips () const
- virtual void setShowToolTips ( bool b )

### treeStepSize : int

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.

Access functions:

- int treeStepSize () const
- virtual void setTreeStepSize ( int )

## Member Function Documentation

### Q3ListView::Q3ListView ( QWidget * parent = 0, const char * name = 0, Qt::WindowFlags f = 0 )

Constructs a new empty list view called name with parent parent and widget attributes f.

This constructor sets the `WA_StaticContent` and the `Qt::WA_NoBackground` attributes to boost performance when drawing Q3ListViewItems. This may be unsuitable for custom Q3ListViewItem classes, in which case Qt::WA_StaticContents and Qt::WA_NoBackground should be cleared on the viewport() after construction.

See also QWidget::setAttribute().

### Q3ListView::~Q3ListView ()

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

### int Q3ListView::addColumn ( const QString & label, int width = -1 ) `[virtual]`

Adds a width pixels wide column with the column header label to the list view, 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().

### int Q3ListView::addColumn ( const QIcon & icon, const QString & label, int width = -1 ) `[virtual]`

This is an overloaded member function, provided for convenience.

Adds a width pixels wide new column with the header label and the icon to the list view, 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().

### void Q3ListView::adjustColumn ( int col ) `[slot]`

Adjusts the column col to its preferred width

### void Q3ListView::clear () `[virtual slot]`

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

See also triggerUpdate().

### void Q3ListView::clearSelection () `[virtual]`

Sets all the 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 setMultiSelection().

### void Q3ListView::clicked ( Q3ListViewItem * item ) `[signal]`

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

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::clicked ( Q3ListViewItem * item, const QPoint & pnt, int c ) `[signal]`

This is an overloaded member function, provided for convenience.

This signal is emitted whenever the user clicks (mouse pressed and mouse released) in the list view. item is 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 in global coordinates. 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.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::collapsed ( Q3ListViewItem * 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 Q3ListView::columnAlignment ( int column ) const

Returns the alignment of column column. The default is `Qt::AlignAuto`.

See also setColumnAlignment() and Qt::Alignment.

### QString Q3ListView::columnText ( int c ) const

Returns the text of column c.

See also setColumnText().

### int Q3ListView::columnWidth ( int c ) const

Returns the width of column c.

See also setColumnWidth().

### WidthMode Q3ListView::columnWidthMode ( int c ) const

Returns the `WidthMode` for column c.

See also setColumnWidthMode().

### void Q3ListView::contentsMouseDoubleClickEvent ( QMouseEvent * e ) `[virtual protected]`

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

Reimplemented from Q3ScrollView.

### void Q3ListView::contentsMouseMoveEvent ( QMouseEvent * e ) `[virtual protected]`

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

Reimplemented from Q3ScrollView.

### void Q3ListView::contentsMousePressEvent ( QMouseEvent * e ) `[virtual protected]`

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

Reimplemented from Q3ScrollView.

### void Q3ListView::contentsMouseReleaseEvent ( QMouseEvent * e ) `[virtual protected]`

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

Reimplemented from Q3ScrollView.

### void Q3ListView::contextMenuRequested ( Q3ListViewItem * item, const QPoint & pos, int col ) `[signal]`

This signal is emitted when the user invokes a context menu with the right mouse button or with special system keys. If the keyboard was used item is the current item; if the mouse was used, item is the item under the mouse pointer or 0 if there is no item under the mouse pointer. If no item is clicked, the column index emitted is -1.

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.

### void Q3ListView::currentChanged ( Q3ListViewItem * item ) `[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 made no item current. This can happen, for example, if all the items in the list view are deleted.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

See also setCurrentItem() and currentItem().

### Q3ListViewItem * Q3ListView::currentItem () const

Returns the current item, or 0 if there isn't one.

See also setCurrentItem().

### void Q3ListView::doAutoScroll () `[protected slot]`

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

### void Q3ListView::doubleClicked ( Q3ListViewItem * 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.

### void Q3ListView::doubleClicked ( Q3ListViewItem * item, const QPoint & point, int column ) `[signal]`

This is an overloaded member function, provided for convenience.

This signal is emitted when a double-click occurs. It's emitted on the second button press, not the second button release. The item is the Q3ListViewItem the button was double-clicked on (which could be 0 if it wasn't double-clicked on an item). The point where the double-click occurred is given in global coordinates. If an item was double-clicked on, column is the column within the item that was double-clicked; otherwise column is -1.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### Q3DragObject * Q3ListView::dragObject () `[virtual protected]`

If the user presses the mouse on an item and starts moving the mouse, and the item allow dragging (see Q3ListViewItem::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 Q3DragObject depending on the selected items.

### void Q3ListView::drawContentsOffset ( QPainter * p, int ox, int oy, int cx, int cy, int cw, int ch ) `[virtual protected]`

Calls Q3ListViewItem::paintCell() and Q3ListViewItem::paintBranches() as necessary 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 Q3ScrollView.

### void Q3ListView::dropped ( QDropEvent * e ) `[signal]`

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

e provides all the information about the drop.

### void Q3ListView::ensureItemVisible ( const Q3ListViewItem * i )

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

See also itemRect() and Q3ScrollView::ensureVisible().

### bool Q3ListView::eventFilter ( QObject * o, QEvent * e ) `[virtual]`

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

Reimplemented from QObject.

### void Q3ListView::expanded ( Q3ListViewItem * 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().

### Q3ListViewItem * Q3ListView::findItem ( const QString & text, int column, ComparisonFlags compare = ExactMatch | Qt::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 ComparisonFlags values in the compare flag, to control how the matching is performed. The default comparison mode is case-sensitive, exact match.

### Q3ListViewItem * Q3ListView::firstChild () const

Returns the first item in this Q3ListView. Returns 0 if there is no first item.

A list view's items can be traversed using firstChild() and nextSibling() or using a Q3ListViewItemIterator.

See also itemAt(), Q3ListViewItem::itemBelow(), and Q3ListViewItem::itemAbove().

### Q3Header * Q3ListView::header () const

Returns the Q3Header object that manages this list view's columns. Please don't modify the header behind the list view's back.

You may safely call Q3Header::setClickEnabled(), Q3Header::setResizeEnabled(), Q3Header::setMovingEnabled(), Q3Header::hide() and all the const Q3Header functions.

### void Q3ListView::hideColumn ( int column )

Hides the column specified at column. This is a convenience function that calls setColumnWidth(column, 0).

Note: The user may still be able to resize the hidden column using the header handles. To prevent this, call setResizeEnabled(false, column) on the list views header.

See also setColumnWidth().

### void Q3ListView::insertItem ( Q3ListViewItem * 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 Q3ListViewItem::takeItem(i) and need to reinsert i elsewhere.

See also Q3ListViewItem::takeItem() and takeItem().

### void Q3ListView::invertSelection () `[virtual slot]`

Inverts the selection. Only works in `Multi` and `Extended` selection modes.

### bool Q3ListView::isOpen ( const Q3ListViewItem * item ) const

Returns true if this list view item has children and they are not explicitly hidden; otherwise returns false.

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

See also setOpen().

### bool Q3ListView::isRenaming () const

Returns true if an item is being renamed; otherwise returns false.

### bool Q3ListView::isSelected ( const Q3ListViewItem * i ) const

Returns true if the list view item i is selected; otherwise returns false.

See also Q3ListViewItem::isSelected().

### Q3ListViewItem * Q3ListView::itemAt ( const QPoint & viewPos ) const

Returns the list view item at viewPos. Note that viewPos is in the viewport()'s coordinate system, 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:

     Q3ListViewItem *i = itemAt(p);
     if (i) {
         if (p.x() > header()->sectionPos(header()->mapToIndex(0)) +
                 treeStepSize() * (i->depth() + (rootIsDecorated() ? 1 : 0)) + itemMargin() ||
                 p.x() < header()->sectionPos(header()->mapToIndex(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(), itemRect(), and viewportToContents().

### int Q3ListView::itemPos ( const Q3ListViewItem * 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 Q3ListViewItem::itemPos().

See also itemAt() and itemRect().

### QRect Q3ListView::itemRect ( const Q3ListViewItem * item ) const

Returns the rectangle on the screen that item item occupies in viewport()'s coordinates, or an invalid rectangle if item is 0 or is not currently visible.

The rectangle returned does not include any children of the rectangle (i.e. it uses Q3ListViewItem::height(), rather than Q3ListViewItem::totalHeight()). If you want the rectangle to include children you can use something like this:

     QRect r(listView->itemRect(item));
     r.setHeight(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 Q3ListView::itemRenamed ( Q3ListViewItem * item, int col, const QString & text ) `[signal]`

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

See also Q3ListViewItem::setRenameEnabled().

### void Q3ListView::itemRenamed ( Q3ListViewItem * item, int col ) `[signal]`

This is an overloaded member function, provided for convenience.

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

See also Q3ListViewItem::setRenameEnabled().

### Q3ListViewItem * Q3ListView::lastItem () const

Returns the last item in the list view tree. Returns 0 if there are no items in the Q3ListView.

This function is slow because it traverses the entire tree to find the last item.

### void Q3ListView::mouseButtonClicked ( int button, Q3ListViewItem * item, const QPoint & pos, int c ) `[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 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.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::mouseButtonPressed ( int button, Q3ListViewItem * item, const QPoint & pos, int c ) `[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 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.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::onItem ( Q3ListViewItem * i ) `[signal]`

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

### void Q3ListView::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 Q3ListView::paintEmptyArea ( QPainter * p, const QRect & rect ) `[virtual protected]`

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

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

### void Q3ListView::pressed ( Q3ListViewItem * item ) `[signal]`

This signal is emitted whenever the user presses the mouse button in a list view. item is 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.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::pressed ( Q3ListViewItem * item, const QPoint & pnt, int c ) `[signal]`

This is an overloaded member function, provided for convenience.

This signal is emitted whenever the user presses the mouse button in a list view. item is 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 in global coordinates, and c is the column where the mouse cursor was when the user pressed the mouse button.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

### void Q3ListView::removeColumn ( int index ) `[virtual]`

Removes the column at position index.

### void Q3ListView::removeItem ( Q3ListViewItem * item ) `[virtual]`

Removes the given item. Use takeItem() instead.

### void Q3ListView::repaintItem ( const Q3ListViewItem * item ) const

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

### void Q3ListView::resizeEvent ( QResizeEvent * e ) `[virtual protected]`

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

Reimplemented from QWidget.

### void Q3ListView::returnPressed ( Q3ListViewItem * item ) `[signal]`

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

### void Q3ListView::rightButtonClicked ( Q3ListViewItem * item, const QPoint & point, int column ) `[signal]`

This signal is emitted when the right button is clicked. The item is the Q3ListViewItem the button was clicked on (which could be 0 if it wasn't clicked on an item). The point where the click occurred is given in global coordinates. If an item was clicked on, column is the column within the item that was clicked; otherwise column is -1.

### void Q3ListView::rightButtonPressed ( Q3ListViewItem * item, const QPoint & point, int column ) `[signal]`

This signal is emitted when the right button is pressed. The item is the Q3ListViewItem the button was pressed on (which could be 0 if it wasn't pressed on an item). The point where the press occurred is given in global coordinates. If an item was pressed on, column is the column within the item that was pressed; otherwise column is -1.

### void Q3ListView::selectAll ( bool select ) `[virtual slot]`

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

### Q3ListViewItem * Q3ListView::selectedItem () const

Returns 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 not in `Single` selection mode this function returns 0.

See also setSelected() and setMultiSelection().

### void Q3ListView::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.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

See also setSelected() and Q3ListViewItem::setSelected().

### void Q3ListView::selectionChanged ( Q3ListViewItem * item ) `[signal]`

This is an overloaded member function, provided for convenience.

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.

In `Multi` selection mode, use the no argument overload of this signal.

Warning: Do not delete any Q3ListViewItem objects in slots connected to this signal.

See also setSelected(), Q3ListViewItem::setSelected(), and currentChanged().

### void Q3ListView::setColumnAlignment ( int column, int align ) `[virtual]`

Sets column column's alignment to align. The alignment is ultimately passed to Q3ListViewItem::paintCell() for each item in the list view. For horizontally aligned text with Qt::AlignLeft or Qt::AlignHCenter the ellipsis (...) will be to the right, for Qt::AlignRight the ellipsis will be to the left.

See also columnAlignment() and Qt::Alignment.

### void Q3ListView::setColumnText ( int column, const QString & label ) `[virtual]`

Sets the heading of column column to label.

See also columnText().

### void Q3ListView::setColumnText ( int column, const QIcon & icon, const QString & label ) `[virtual]`

This is an overloaded member function, provided for convenience.

Sets the heading of column column to icon and label.

See also columnText().

### void Q3ListView::setColumnWidth ( int column, int w ) `[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.

See also columnWidth().

### void Q3ListView::setColumnWidthMode ( int c, WidthMode mode ) `[virtual]`

Sets column c's width mode to mode. The default depends on the original width argument to addColumn().

See also columnWidthMode() and Q3ListViewItem::width().

### void Q3ListView::setCurrentItem ( Q3ListViewItem * i ) `[virtual]`

Sets item i to be the current item and repaints appropriately (i.e. highlights the item). The current item is used for keyboard navigation and focus indication; it is independent of any selected items, although a selected item can also be the current item.

See also currentItem() and setSelected().

### void Q3ListView::setOpen ( Q3ListViewItem * item, bool open ) `[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 isOpen(), Q3ListViewItem::setOpen(), and Q3ListViewItem::setExpandable().

### void Q3ListView::setSelected ( Q3ListViewItem * item, bool selected ) `[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 Q3ListViewItem::setSelected(), this function updates the list view as necessary and emits the selectionChanged() signals.

setCurrentItem(), setSelectionAnchor()

See also isSelected(), setMultiSelection(), and isMultiSelection().

### void Q3ListView::setSelectionAnchor ( Q3ListViewItem * item )

Sets the selection anchor to item, if item is selectable.

The selection anchor is the item that remains selected when Shift-selecting with either mouse or keyboard in `Extended` selection mode.

See also setSelected().

### void Q3ListView::setSortColumn ( int column )

Sets the sorting column for the list view.

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 must click on a column header to sort the list view.

See also sortColumn() and setSorting().

### void Q3ListView::setSortOrder ( Qt::SortOrder order )

Sets the sort order for the items in the list view to order.

See also sortOrder() and setSorting().

### void Q3ListView::setSorting ( int column, bool ascending = true ) `[virtual]`

Sets the list view to be sorted by column column 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 must click on a column header to sort the list view.

### void Q3ListView::sort () `[virtual]`

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

### int Q3ListView::sortColumn () const

Returns the column by which the list view is sorted, or -1 if sorting is disabled.

See also setSortColumn() and sortOrder().

### Qt::SortOrder Q3ListView::sortOrder () const

Returns the sorting order of the list view items.

See also setSortOrder() and sortColumn().

### void Q3ListView::spacePressed ( Q3ListViewItem * item ) `[signal]`

This signal is emitted when Space is pressed. The item parameter is the currentItem().

### void Q3ListView::startDrag () `[virtual protected]`

Starts a drag.

### void Q3ListView::takeItem ( Q3ListViewItem * i ) `[virtual]`

Removes item i from the list view; i must be a top-level item. The warnings regarding Q3ListViewItem::takeItem() apply to this function, too.

See also insertItem().

### void Q3ListView::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 Q3ListView::updateContents () `[protected slot]`

Updates the sizes of the viewport, header, scroll bars and so on.

Warning: Don't call this directly; call triggerUpdate() instead.