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 TQListView, add some column headers using addColumn() and create one or more TQListViewItem or TQCheckListItem objects with the TQListView as parent:
l - l. 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 should show 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()
To handle events such as mouse presses on the list view, derived classes can reimplement the TQScrollView 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 (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 TQListViewItem::itemBelow(); over a list view's top-level items using TQListViewItem::firstChild() and TQListViewItem::nextSibling(); or every item using a TQListViewItemIterator. See the TQListViewItem documentation for examples of traversal.
An item can be moved amongst its siblings using TQListViewItem::moveItem(). To move an item in the hierarchy use takeItem() and insertItem(). Item's (and all their child items) are deleted with \fCdelete\fR; to delete all the list view's items use clear().
There are a variety of selection modes described in the TQListView::SelectionMode documentation. The default is Single selection, which you can change using setSelectionMode().
Because TQListView 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()).
TQListView 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(TQListViewItem*) (applicable only to a Single selection list view), and currentChanged(TQListViewItem*). The second group consists of doubleClicked(TQListViewItem*), returnPressed(TQListViewItem*), rightButtonClicked(TQListViewItem*, const TQPoint&, 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, TQListView 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 TQListView::SelectionMode for details.
The list view can be navigated either using the mouse or the keyboard. Clicking a \fB-\fR icon closes an item (hides its children) and clicking a \fB+\fR icon opens an item (shows its children). The keyboard controls are these: <center>.nf
.TS
l - l. 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 ( Right Arrow If the current item is closed (
.TE
.fi
</center>
.PP
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.
.PP
\fBWarning:\fR The list view assumes ownership of all list view items and will delete them when it does not need them any more.
\fCTQListView::Single\fR - When the user selects an item, any already-selected item becomes unselected. The user can unselect the selected item by clicking on some empty space within the view.
\fCTQListView::Multi\fR - 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. Also, multiple items can be selected by dragging the mouse while the left mouse button stays pressed.
\fCTQListView::Extended\fR - 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.
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.
\fCTQListView::Maximum\fR - 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.
Performance is boosted by modifying the widget flags \fIf\fR so that only part of the TQListViewItem children is redrawn. This may be unsuitable for custom TQListViewItem classes, in which case WStaticContents and WNoAutoErase should be cleared.
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 \fIall\fR items.
This signal is emitted whenever the user clicks (mouse pressed \fIand\fR mouse released) in the list view. \fIitem\fR is the clicked list view item, or 0 if the user didn't click on an item.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
.PP
This signal is emitted whenever the user clicks (mouse pressed \fIand\fR mouse released) in the list view. \fIitem\fR is the clicked list view item, or 0 if the user didn't click on an item. \fIpnt\fR is the position where the user has clicked in global coordinates. If \fIitem\fR is not 0, \fIc\fR is the list view column into which the user pressed; if \fIitem\fR is 0 \fIc\fR's value is undefined.
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 \fIitem\fR is the current item; if the mouse was used, \fIitem\fR 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.
.PP
\fIpos\fR is the position for the context menu in the global coordinate system.
.PP
\fIcol\fR is the column on which the user pressed, or -1 if the signal was triggered by a key event.
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.
.PP
The argument is the newly current item, or 0 if the change made no item current. This can happen, for example, if all items in the list view are deleted.
This signal is emitted whenever an item is double-clicked. It's emitted on the second button press, not the second button release. The arguments are the relevant TQListViewItem (may be 0), the point in global coordinates and the relevant column (or -1 if the click was outside the list).
\fBThis function is obsolete.\fR It is provided to keep old source working. We strongly advise against using it in new code. (use doubleClicked( TQListViewItem *, const TQPoint&, int ))
This signal is emitted whenever an item is double-clicked. It's emitted on the second button press, not the second button release. \fIitem\fR is the list view item on which the user did the double-click.
If the user presses the mouse on an item and starts moving the mouse, and the item allow dragging (see TQListViewItem::setDragEnabled()), this function is called to get a drag object and a drag is started unless dragObject() returns 0.
.SH "void TQListView::drawContentsOffset ( TQPainter * p, int ox, int oy, int cx, int cy, int cw, int ch )\fC [virtual protected]\fR"
Calls TQListViewItem::paintCell() and TQListViewItem::paintBranches() as necessary for all list view items that require repainting in the \fIcw\fR pixels wide and \fIch\fR pixels high bounding rectangle starting at position \fIcx\fR, \fIcy\fR with offset \fIox\fR, \fIoy\fR. Uses the painter \fIp\fR.
Ensures that item \fIi\fR is visible, scrolling the list view vertically if necessary and opening (expanding) any parent items if this is required to show the item.
Finds the first list view item in column \fIcolumn\fR, that matches \fItext\fR and returns the item, or returns 0 of no such item could be found. The search starts from the current item if the current item exists, otherwise it starts from the first list view item. After reaching the last item the search continues from the first item. Pass OR-ed together TQt::StringComparisonMode values in the \fIcompare\fR flag, to control how the matching is performed. The default comparison mode is case-sensitive, exact match.
You may safely call TQHeader::setClickEnabled(), TQHeader::setResizeEnabled(), TQHeader::setMovingEnabled(), TQHeader::hide() and all the const TQHeader functions.
Hides the column specified at \fIcolumn\fR. This is a convenience function that calls setColumnWidth( \fIcolumn\fR, 0 ).
.PP
Note: The user may still be able to resize the hidden column using the header handles. To prevent this, call setResizeEnabled(FALSE, \fIcolumn\fR) on the list views header.
.SH "void TQListView::insertItem ( TQListViewItem * i )\fC [virtual]\fR"
Inserts item \fIi\fR into the list view as a top-level item. You do not need to call this unless you've called takeItem(\fIi\fR) or TQListViewItem::takeItem(\fIi\fR) and need to reinsert \fIi\fR elsewhere.
Returns TRUE if the list view is in multi-selection or extended-selection mode; otherwise returns FALSE. See the "multiSelection" property for details.
Returns the list view item at \fIviewPos\fR. Note that \fIviewPos\fR is in the viewport()'s coordinate system, not in the list view's own, much larger, coordinate system.
.PP
itemAt() returns 0 if there is no such item.
.PP
Note that you also get the pointer to the item if \fIviewPos\fR points to the root decoration (see setRootIsDecorated()) of the item. To check whether or not \fIviewPos\fR is on the root decoration of the item, you can do something like this:
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).
.PP
See also itemPos(), itemRect(), and viewportToContents().
Returns the y-coordinate of \fIitem\fR 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.
Returns the rectangle on the screen that item \fIi\fR occupies in viewport()'s coordinates, or an invalid rectangle if \fIi\fR is 0 or is not currently visible.
The rectangle returned does not include any children of the rectangle (i.e. it uses TQListViewItem::height(), rather than TQListViewItem::totalHeight()). If you want the rectangle to include children you can use something like this:
This signal is emitted whenever the user clicks (mouse pressed \fIand\fR mouse released) in the list view at position \fIpos\fR. \fIbutton\fR is the mouse button that the user pressed, \fIitem\fR is the clicked list view item or 0 if the user didn't click on an item. If \fIitem\fR is not 0, \fIc\fR is the list view column into which the user pressed; if \fIitem\fR is 0 \fIc\fR's value is undefined.
This signal is emitted whenever the user pressed the mouse button in the list view at position \fIpos\fR. \fIbutton\fR is the mouse button which the user pressed, \fIitem\fR is the pressed list view item or 0 if the user didn't press on an item. If \fIitem\fR is not 0, \fIc\fR is the list view column into which the user pressed; if \fIitem\fR is 0 \fIc\fR's value is undefined.
This signal is emitted whenever the user presses the mouse button in a list view. \fIitem\fR 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.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
.PP
This signal is emitted whenever the user presses the mouse button in a list view. \fIitem\fR 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. \fIpnt\fR is the position of the mouse cursor in global coordinates, and \fIc\fR is the column where the mouse cursor was when the user pressed the mouse button.
This signal is emitted when the right button is clicked (i.e. when it's released). The arguments are the relevant TQListViewItem (may be 0), the point in global coordinates and the relevant column (or -1 if the click was outside the list).
This signal is emitted when the right button is pressed. The arguments are the relevant TQListViewItem (may be 0), the point in global coordinates and the relevant column (or -1 if the click was outside the list).
If \fIselect\fR 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 \fIselect\fR.
This signal is emitted whenever the set of selected items has changed (normally before the screen update). It is available in Single, Multi, and Extended selection modes, but is most useful in Multi selection mode.
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
.PP
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. If the selection is cleared (when, for example, the user clicks in the unused area of the list view) then this signal will not be emitted.
.PP
In Multi selection mode, use the no argument overload of this signal.
.SH "void TQListView::setColumnAlignment ( int column, int align )\fC [virtual]\fR"
Sets column \fIcolumn\fR's alignment to \fIalign\fR. The alignment is ultimately passed to TQListViewItem::paintCell() for each item in the list view. For horizontally aligned text with TQt::AlignLeft or TQt::AlignHCenter the ellipsis (...) will be to the right, for TQt::AlignRight the ellipsis will be to the left.
Sets the width of column \fIcolumn\fR to \fIw\fR pixels. Note that if the column has a WidthMode other than Manual, this width setting may be subsequently overridden.
Sets item \fIi\fR 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.
.PP
This function does not set the selection anchor. Use setSelectionAnchor() instead.
If the list view is in Single selection mode and \fIselected\fR is TRUE, the currently selected item is unselected and \fIitem\fR is made current. Unlike TQListViewItem::setSelected(), this function updates the list view as necessary and emits the selectionChanged() signals.
If \fIcolumn\fR is -1, sorting is disabled and the user cannot sort columns by clicking on the column headers. If \fIcolumn\fR is larger than the number of columns the user must click on a column header to sort the list view.
Sets the list view to be sorted by column \fIcolumn\fR in ascending order if \fIascending\fR is TRUE or descending order if it is FALSE.
.PP
If \fIcolumn\fR is -1, sorting is disabled and the user cannot sort columns by clicking on the column headers. If \fIcolumn\fR is larger than the number of columns the user must click on a column header to sort the list view.
.SH "void TQListView::takeItem ( TQListViewItem * i )\fC [virtual]\fR"
Removes item \fIi\fR from the list view; \fIi\fR must be a top-level item. The warnings regarding TQListViewItem::takeItem() apply to this function, too.
This property holds the number of columns in this list view.
.PP
Get this property's value with columns().
.PP
See also addColumn() and removeColumn().
.SH "RenameAction defaultRenameAction"
This property holds what action to perform when the editor loses focus during renaming.
.PP
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.
.PP
Set this property's value with setDefaultRenameAction() and get this property's value with defaultRenameAction().
.SH "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. TQListViewItem::paintFocus() draws in the margin.
Set this property's value with setItemMargin() and get this property's value with itemMargin().
.SH "bool multiSelection"
\fBThis function is obsolete.\fR It is provided to keep old source working. We strongly advise against using it in new code.
.PP
This property holds whether the list view is in multi-selection or extended-selection mode.
.PP
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.
.PP
The default selection mode is Single.
.PP
See also selectionMode.
.PP
Set this property's value with setMultiSelection() and get this property's value with isMultiSelection().
.SH "ResizeMode resizeMode"
This property holds whether all, none or the only the last column should be resized.
.PP
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.
.PP
\fBWarning:\fR Setting the resize mode should be done after all necessary columns have been added to the list view, otherwise the behavior is undefined.
Set this property's value with setResizeMode() and get this property's value with resizeMode().
.SH "bool rootIsDecorated"
This property holds whether the list view shows open/close signs on root items.
.PP
Open/close signs are small \fB+\fR or \fB-\fR symbols in windows style, or arrows in Motif style. The default is FALSE.
.PP
Set this property's value with setRootIsDecorated() and get this property's value with rootIsDecorated().
.SH "SelectionMode selectionMode"
This property holds the list view's selection mode.
.PP
The mode can be Single (the default), Extended, Multi or NoSelection.
.PP
See also multiSelection.
.PP
Set this property's value with setSelectionMode() and get this property's value with selectionMode().
.SH "bool showSortIndicator"
This property holds whether the list view header should display a sort indicator.
.PP
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).
