A tree control presents information as a hierarchy, with items that may be expanded to show further items.
Items in a tree control are referenced by wxTreeItemId (not implemented in wx) handles,
which may be tested for validity by calling wxTreeItemId::IsOk() (not implemented in wx).
A similar control with a fully native implementation for GTK+ and macOS as well is wxDataViewTreeCtrl
(not implemented in wx).
To intercept events from a tree control, use the event table macros described in wxTreeEvent.
Styles
This class supports the following styles:
wxTR_EDIT_LABELS: Use this style if you wish the user to be able to edit labels in the tree control.
wxTR_NO_BUTTONS: For convenience to document that no buttons are to be drawn.
wxTR_HAS_BUTTONS: Use this style to show + and - buttons to the left of parent items.
wxTR_TWIST_BUTTONS: Selects alternative style of +/
-buttons and shows rotating ("twisting") arrows instead. Currently this style is only implemented under Microsoft Windows Vista and later Windows versions and is ignored under the other platforms as enabling it is equivalent to usingwxSystemThemedControl::EnableSystemTheme()(not implemented in wx).wxTR_NO_LINES: Use this style to hide vertical level connectors.
wxTR_FULL_ROW_HIGHLIGHT: Use this style to have the background colour and the selection highlight extend over the entire horizontal row of the tree control window. (This flag is ignored under Windows unless you specify
wxTR_NO_LINESas well.)wxTR_LINES_AT_ROOT: Use this style to show lines leading to the root nodes (unless no
wxTR_NO_LINESis also used, in which case no lines are shown). Note that in the MSW version, if this style is omitted, not only the lines, but also the button used for expanding the root item is not shown, which can be unexpected, so it is recommended to always use it.wxTR_HIDE_ROOT: Use this style to suppress the display of the root node, effectively causing the first-level nodes to appear as a series of root nodes.
wxTR_ROW_LINES: Use this style to draw a contrasting border between displayed rows.
wxTR_HAS_VARIABLE_ROW_HEIGHT: Use this style to cause row heights to be just big enough to fit the content. If not set, all rows use the largest row height. The default is that this flag is unset. Generic only.
wxTR_SINGLE: For convenience to document that only one item may be selected at a time. Selecting another item causes the current selection, if any, to be deselected. This is the default.
wxTR_MULTIPLE: Use this style to allow a range of items to be selected. If a second range is selected, the current range, if any, is deselected.
wxTR_DEFAULT_STYLE: The set of flags that are closest to the defaults for the native control for a particular toolkit.
See also overview_windowstyles.
Win32 notes:
wxTreeCtrl class uses the standard common treeview control under Win32 implemented in
the system library comctl32.dll. Some versions of this library are known to have bugs with
handling the tree control colours: the usual symptom is that the expanded items leave
black (or otherwise incorrectly coloured) background behind them, especially for the
controls using non-default background colour. The recommended solution is to upgrade the
comctl32.dll to a newer version: see http://www.microsoft.com/downloads/details.aspx?familyid=cb2cf3a2-8025-4e8f-8511-9b476a8d35d2
See:
This class is derived, and can use functions, from:
wxWidgets docs: wxTreeCtrl
Events
Event types emitted from this class:
Summary
Functions
Adds the root node to the tree, returning the new item.
Appends an item to the end of the branch identified by parent, return a new item id.
Sets the normal image list.
Sets the state image list.
Collapses the given item.
Collapses the given item and removes all children.
Creates the tree control.
Deletes the specified item.
Deletes all items in the control.
Deletes all children of the given item (but not the item itself).
Destroys the object
Starts editing the label of the given item.
Scrolls and/or expands items to ensure that the given item is visible.
Expands the given item.
Retrieves the rectangle bounding the item.
Returns the number of items in the branch.
Returns the number of items in the control.
Returns the edit control being currently used to edit a label.
Returns the first child; call getNextChild/3 for the next child.
Returns the first visible item.
Returns the normal image list.
Returns the current tree control indentation.
Returns the background colour of the item.
Returns the tree item data associated with the item.
Returns the font of the item label.
Gets the specified item image.
Returns the item's parent.
Returns the item label.
Returns the colour of the item label.
Returns the last child of the item (or an invalid tree item if this item has no children).
Returns the next child; call getFirstChild/2 for the first child.
Returns the next sibling of the specified item; call getPrevSibling/2 for the previous
sibling.
Returns the next visible item or an invalid item if this item is the last visible one.
Returns the previous sibling of the specified item; call getNextSibling/2 for the next
sibling.
Returns the previous visible item or an invalid item if this item is the first visible one.
Returns the root item for the tree control.
Returns the selection, or an invalid item if there is no selection.
Fills the array of tree items passed in with the currently selected items.
Returns the state image list (from which application-defined state images are taken).
Calculates which (if any) item is under the given point, returning the tree item id at
this point plus extra information flags.
Inserts an item after a given one (previous).
Returns true if the given item is in bold state.
Returns true if the item is expanded (only makes sense if it has children).
Returns true if the item is selected.
Returns true if the item is valid.
Returns true if the item is visible on the screen.
Returns true if the item has children.
Default Constructor.
Constructor, creating and showing a tree control.
Appends an item as the first child of parent, return a new item id.
Scrolls the specified item into view.
Selects the given item.
Sets the normal image list.
Sets the indentation for the tree control.
Sets the colour of the item's background.
Makes item appear in bold font if bold parameter is true or resets it to the normal
state.
Sets the item client data.
Gives the item the visual feedback for Drag'n'Drop actions, which is useful if something is dragged from the outside onto the tree control (as opposed to a DnD operation within the tree control, which already is implemented internally).
Sets the item's font.
Force appearance of the button next to the item.
Sets the specified item's image.
Sets the item label.
Sets the colour of the item's text.
Sets the state image list (from which application-defined state images are taken).
Sets the mode flags associated with the display of the tree control.
Sorts the children of the given item using OnCompareItems() (not implemented in wx).
Toggles the given item between collapsed and expanded states.
Toggles the given item between selected and unselected states.
Removes the selection from the currently selected item (if any).
This function either behaves the same as unselect/1 if the control doesn't have wxTR\_MULTIPLE
style, or removes the selection from all items if it does have this style.
Unselects the given item.
Types
-type wxTreeCtrl() :: wx:wx_object().
Functions
-spec addRoot(This, Text) -> integer() when This :: wxTreeCtrl(), Text :: unicode:chardata().
-spec addRoot(This, Text, [Option]) -> integer() when This :: wxTreeCtrl(), Text :: unicode:chardata(), Option :: {image, integer()} | {selectedImage, integer()} | {data, term()}.
Adds the root node to the tree, returning the new item.
The image and selImage parameters are an index within the normal image list
specifying the image to use for unselected and selected items, respectively. If image >
-1 and selImage is -1, the same image is used for both selected and unselected items.
-spec appendItem(This, Parent, Text) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Text :: unicode:chardata().
-spec appendItem(This, Parent, Text, [Option]) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Text :: unicode:chardata(), Option :: {image, integer()} | {selectedImage, integer()} | {data, term()}.
Appends an item to the end of the branch identified by parent, return a new item id.
The image and selImage parameters are an index within the normal image list
specifying the image to use for unselected and selected items, respectively. If image >
-1 and selImage is -1, the same image is used for both selected and unselected items.
Sets the normal image list.
The image list assigned with this method will be automatically deleted by wxTreeCtrl
as appropriate (i.e. it takes ownership of the list).
See: setImageList/2
Sets the state image list.
Image list assigned with this method will be automatically deleted by wxTreeCtrl as
appropriate (i.e. it takes ownership of the list).
See: setStateImageList/2
collapse(This :: wxTreeCtrl(), Item :: integer()) -> ok
Collapses the given item.
collapseAndReset(This :: wxTreeCtrl(), Item :: integer()) -> ok
Collapses the given item and removes all children.
-spec create(This, Parent) -> boolean() when This :: wxTreeCtrl(), Parent :: wxWindow:wxWindow().
-spec create(This, Parent, [Option]) -> boolean() when This :: wxTreeCtrl(), Parent :: wxWindow:wxWindow(), Option :: {id, integer()} | {pos, {X :: integer(), Y :: integer()}} | {size, {W :: integer(), H :: integer()}} | {style, integer()} | {validator, wx:wx_object()}.
Creates the tree control.
See new/2 for further details.
delete(This :: wxTreeCtrl(), Item :: integer()) -> ok
Deletes the specified item.
A EVT_TREE_DELETE_ITEM event will be generated.
This function may cause a subsequent call to getNextChild/3 to fail.
deleteAllItems(This :: wxTreeCtrl()) -> ok
Deletes all items in the control.
This function generates wxEVT_TREE_DELETE_ITEM events for each item being deleted,
including the root one if it is shown, i.e. unless wxTR_HIDE_ROOT style is used.
deleteChildren(This :: wxTreeCtrl(), Item :: integer()) -> ok
Deletes all children of the given item (but not the item itself).
A wxEVT_TREE_DELETE_ITEM event will be generated for every item being deleted.
If you have called setItemHasChildren/3, you may need to call it again since deleteChildren/2 does not automatically clear
the setting.
destroy(This :: wxTreeCtrl()) -> ok
Destroys the object
editLabel(This :: wxTreeCtrl(), Item :: integer()) -> Result
Types
Result = wxTextCtrl:wxTextCtrl()
Starts editing the label of the given item.
This function generates a EVT_TREE_BEGIN_LABEL_EDIT event which can be vetoed so that
no text control will appear for in-place editing.
If the user changed the label (i.e. s/he does not press ESC or leave the text control
without changes, a EVT_TREE_END_LABEL_EDIT event will be sent which can be vetoed as well.
See: wxTreeEvent
ensureVisible(This :: wxTreeCtrl(), Item :: integer()) -> ok
Scrolls and/or expands items to ensure that the given item is visible.
This method can be used, and will work, even while the window is frozen (see wxWindow:freeze/1).
expand(This :: wxTreeCtrl(), Item :: integer()) -> ok
Expands the given item.
-spec getBoundingRect(This, Item) -> Result when Result :: {Res :: boolean(), Rect :: {X :: integer(), Y :: integer(), W :: integer(), H :: integer()}}, This :: wxTreeCtrl(), Item :: integer().
-spec getBoundingRect(This, Item, [Option]) -> Result when Result :: {Res :: boolean(), Rect :: {X :: integer(), Y :: integer(), W :: integer(), H :: integer()}}, This :: wxTreeCtrl(), Item :: integer(), Option :: {textOnly, boolean()}.
Retrieves the rectangle bounding the item.
If textOnly is true, only the rectangle around the item's label will be returned,
otherwise the item's image is also taken into account.
The return value is true if the rectangle was successfully retrieved or false if it was
not (in this case rect is not changed) - for example, if the item is currently invisible.
Notice that the rectangle coordinates are logical, not physical ones. So, for example, the x coordinate may be negative if the tree has a horizontal scrollbar and its position is not 0.
-spec getChildrenCount(This, Item) -> integer() when This :: wxTreeCtrl(), Item :: integer().
-spec getChildrenCount(This, Item, [Option]) -> integer() when This :: wxTreeCtrl(), Item :: integer(), Option :: {recursively, boolean()}.
Returns the number of items in the branch.
If recursively is true, returns the total number of descendants, otherwise only one
level of children is counted.
getCount(This :: wxTreeCtrl()) -> integer()
Returns the number of items in the control.
getEditControl(This :: wxTreeCtrl()) -> Result
Types
Result = wxTextCtrl:wxTextCtrl()
Returns the edit control being currently used to edit a label.
Returns NULL if no label is being edited.
Note: This is currently only implemented for wxMSW.
getFirstChild(This :: wxTreeCtrl(), Item :: integer()) -> Result
Returns the first child; call getNextChild/3 for the next child.
For this enumeration function you must pass in a 'cookie' parameter which is opaque for
the application but is necessary for the library to make these functions reentrant (i.e.
allow more than one enumeration on one and the same object simultaneously). The cookie
passed to getFirstChild/2 and getNextChild/3 should be the same variable.
Returns an invalid tree item (i.e. wxTreeItemId::IsOk() (not implemented in wx) returns
false) if there are no further children.
See:
getFirstVisibleItem(This :: wxTreeCtrl()) -> integer()
Returns the first visible item.
getImageList(This :: wxTreeCtrl()) -> Result
Types
Result = wxImageList:wxImageList()
Returns the normal image list.
getIndent(This :: wxTreeCtrl()) -> integer()
Returns the current tree control indentation.
getItemBackgroundColour(This, Item) -> wx:wx_colour4()
Returns the background colour of the item.
getItemData(This :: wxTreeCtrl(), Item :: integer()) -> term()
Returns the tree item data associated with the item.
getItemFont(This :: wxTreeCtrl(), Item :: integer()) -> wxFont:wxFont()
Returns the font of the item label.
If the font hadn't been explicitly set for the specified item with setItemFont/3, returns an invalid
?wxNullFont font. wxWindow:getFont/1 can be used to retrieve the global tree control font used for the items
without any specific font.
-spec getItemImage(This, Item) -> integer() when This :: wxTreeCtrl(), Item :: integer().
-spec getItemImage(This, Item, [Option]) -> integer() when This :: wxTreeCtrl(), Item :: integer(), Option :: {which, wx:wx_enum()}.
Gets the specified item image.
The value of which may be:
?wxTreeItemIcon_Normal: to get the normal item image.
?wxTreeItemIcon_Selected: to get the selected item image (i.e. the image which is shown when the item is currently selected).
?wxTreeItemIcon_Expanded: to get the expanded image (this only makes sense for items which have children - then this image is shown when the item is expanded and the normal image is shown when it is collapsed).
?wxTreeItemIcon_SelectedExpanded: to get the selected expanded image (which is shown when an expanded item is currently selected).
getItemParent(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the item's parent.
getItemText(This :: wxTreeCtrl(), Item :: integer()) -> unicode:charlist()
Returns the item label.
getItemTextColour(This :: wxTreeCtrl(), Item :: integer()) -> wx:wx_colour4()
Returns the colour of the item label.
getLastChild(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the last child of the item (or an invalid tree item if this item has no children).
See:
Types
This = wxTreeCtrl()
Item = Cookie = integer()
Result = {Res :: integer(), Cookie :: integer()}
Returns the next child; call getFirstChild/2 for the first child.
For this enumeration function you must pass in a 'cookie' parameter which is opaque for
the application but is necessary for the library to make these functions reentrant (i.e.
allow more than one enumeration on one and the same object simultaneously). The cookie
passed to getFirstChild/2 and getNextChild/3 should be the same.
Returns an invalid tree item if there are no further children.
See: getFirstChild/2
getNextSibling(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the next sibling of the specified item; call getPrevSibling/2 for the previous
sibling.
Returns an invalid tree item if there are no further siblings.
See: getPrevSibling/2
getNextVisible(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the next visible item or an invalid item if this item is the last visible one.
Note: The item itself must be visible.
getPrevSibling(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the previous sibling of the specified item; call getNextSibling/2 for the next
sibling.
Returns an invalid tree item if there are no further children.
See: getNextSibling/2
getPrevVisible(This :: wxTreeCtrl(), Item :: integer()) -> integer()
Returns the previous visible item or an invalid item if this item is the first visible one.
Note: The item itself must be visible.
getRootItem(This :: wxTreeCtrl()) -> integer()
Returns the root item for the tree control.
getSelection(This :: wxTreeCtrl()) -> integer()
Returns the selection, or an invalid item if there is no selection.
This function only works with the controls without wxTR_MULTIPLE style, use getSelections/1 for the
controls which do have this style or, if a single item is wanted, use GetFocusedItem()
(not implemented in wx).
getSelections(This :: wxTreeCtrl()) -> Result
Fills the array of tree items passed in with the currently selected items.
This function can be called only if the control has the wxTR_MULTIPLE style.
Returns the number of selected items.
getStateImageList(This :: wxTreeCtrl()) -> Result
Types
Result = wxImageList:wxImageList()
Returns the state image list (from which application-defined state images are taken).
Types
This = wxTreeCtrl()
Point = {X :: integer(), Y :: integer()}
Result = {Res :: integer(), Flags :: integer()}
Calculates which (if any) item is under the given point, returning the tree item id at
this point plus extra information flags.
flags is a bitlist of the following:
wxTREE_HITTEST_ABOVE:Above the client area.wxTREE_HITTEST_BELOW:Below the client area.wxTREE_HITTEST_NOWHERE:In the client area but below the last item.wxTREE_HITTEST_ONITEMBUTTON:On the button associated with an item.wxTREE_HITTEST_ONITEMICON:On the bitmap associated with an item.wxTREE_HITTEST_ONITEMINDENT:In the indentation associated with an item.wxTREE_HITTEST_ONITEMLABEL:On the label (string) associated with an item.wxTREE_HITTEST_ONITEMRIGHT:In the area to the right of an item.wxTREE_HITTEST_ONITEMSTATEICON:On the state icon for a tree view item that is in a user-defined state.wxTREE_HITTEST_TOLEFT:To the right of the client area.wxTREE_HITTEST_TORIGHT:To the left of the client area.
-spec insertItem(This, Parent, Previous, Text) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Previous :: integer(), Text :: unicode:chardata().
-spec insertItem(This, Parent, Previous, Text, [Option]) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Previous :: integer(), Text :: unicode:chardata(), Option :: {image, integer()} | {selImage, integer()} | {data, term()}.
Inserts an item after a given one (previous).
The image and selImage parameters are an index within the normal image list
specifying the image to use for unselected and selected items, respectively. If image >
-1 and selImage is -1, the same image is used for both selected and unselected items.
isBold(This :: wxTreeCtrl(), Item :: integer()) -> boolean()
Returns true if the given item is in bold state.
See: setItemBold/3
isExpanded(This :: wxTreeCtrl(), Item :: integer()) -> boolean()
Returns true if the item is expanded (only makes sense if it has children).
isSelected(This :: wxTreeCtrl(), Item :: integer()) -> boolean()
Returns true if the item is selected.
Returns true if the item is valid.
isVisible(This :: wxTreeCtrl(), Item :: integer()) -> boolean()
Returns true if the item is visible on the screen.
itemHasChildren(This :: wxTreeCtrl(), Item :: integer()) -> boolean()
Returns true if the item has children.
new() -> wxTreeCtrl()
Default Constructor.
-spec new(Parent) -> wxTreeCtrl() when Parent :: wxWindow:wxWindow().
-spec new(Parent, [Option]) -> wxTreeCtrl() when Parent :: wxWindow:wxWindow(), Option :: {id, integer()} | {pos, {X :: integer(), Y :: integer()}} | {size, {W :: integer(), H :: integer()}} | {style, integer()} | {validator, wx:wx_object()}.
Constructor, creating and showing a tree control.
See: create/3
-spec prependItem(This, Parent, Text) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Text :: unicode:chardata().
-spec prependItem(This, Parent, Text, [Option]) -> integer() when This :: wxTreeCtrl(), Parent :: integer(), Text :: unicode:chardata(), Option :: {image, integer()} | {selectedImage, integer()} | {data, term()}.
Appends an item as the first child of parent, return a new item id.
The image and selImage parameters are an index within the normal image list
specifying the image to use for unselected and selected items, respectively. If image >
-1 and selImage is -1, the same image is used for both selected and unselected items.
scrollTo(This :: wxTreeCtrl(), Item :: integer()) -> ok
Scrolls the specified item into view.
Note that this method doesn't work while the window is frozen (See wxWindow:freeze/1), at least under MSW.
See: ensureVisible/2
-spec selectItem(This, Item) -> ok when This :: wxTreeCtrl(), Item :: integer().
-spec selectItem(This, Item, [Option]) -> ok when This :: wxTreeCtrl(), Item :: integer(), Option :: {select, boolean()}.
Selects the given item.
In multiple selection controls, can be also used to deselect a currently selected item if
the value of select is false.
Notice that calling this method will generate wxEVT_TREE_SEL_CHANGING and wxEVT_TREE_SEL_CHANGED
events and that the change could be vetoed by the former event handler.
setImageList(This :: wxTreeCtrl(), ImageList :: wxImageList:wxImageList()) -> ok
Sets the normal image list.
The image list assigned with this method will not be deleted by wxTreeCtrl's
destructor, you must delete it yourself.
See: assignImageList/2
setIndent(This :: wxTreeCtrl(), Indent :: integer()) -> ok
Sets the indentation for the tree control.
Sets the colour of the item's background.
-spec setItemBold(This, Item) -> ok when This :: wxTreeCtrl(), Item :: integer().
-spec setItemBold(This, Item, [Option]) -> ok when This :: wxTreeCtrl(), Item :: integer(), Option :: {bold, boolean()}.
Makes item appear in bold font if bold parameter is true or resets it to the normal
state.
See: isBold/2
setItemData(This :: wxTreeCtrl(), Item :: integer(), Data :: term()) -> ok
Sets the item client data.
Notice that the client data previously associated with the item (if any) is not freed
by this function and so calling this function multiple times for the same item will result
in memory leaks unless you delete the old item data pointer yourself.
-spec setItemDropHighlight(This, Item) -> ok when This :: wxTreeCtrl(), Item :: integer().
-spec setItemDropHighlight(This, Item, [Option]) -> ok when This :: wxTreeCtrl(), Item :: integer(), Option :: {highlight, boolean()}.
Gives the item the visual feedback for Drag'n'Drop actions, which is useful if something is dragged from the outside onto the tree control (as opposed to a DnD operation within the tree control, which already is implemented internally).
Sets the item's font.
All items in the tree should have the same height to avoid text clipping, so the fonts height should be the same for all of them, although font attributes may vary.
See: setItemBold/3
-spec setItemHasChildren(This, Item) -> ok when This :: wxTreeCtrl(), Item :: integer().
-spec setItemHasChildren(This, Item, [Option]) -> ok when This :: wxTreeCtrl(), Item :: integer(), Option :: {has, boolean()}.
Force appearance of the button next to the item.
This is useful to allow the user to expand the items which don't have any children now, but instead adding them only when needed, thus minimizing memory usage and loading time.
-spec setItemImage(This, Item, Image) -> ok when This :: wxTreeCtrl(), Item :: integer(), Image :: integer().
-spec setItemImage(This, Item, Image, [Option]) -> ok when This :: wxTreeCtrl(), Item :: integer(), Image :: integer(), Option :: {which, wx:wx_enum()}.
Sets the specified item's image.
See getItemImage/3 for the description of the which parameter.
Sets the item label.
Sets the colour of the item's text.
Sets the state image list (from which application-defined state images are taken).
Image list assigned with this method will not be deleted by wxTreeCtrl's
destructor, you must delete it yourself.
setWindowStyle(This :: wxTreeCtrl(), Styles :: integer()) -> ok
Sets the mode flags associated with the display of the tree control.
The new mode takes effect immediately.
Note: Generic only; MSW ignores changes.
sortChildren(This :: wxTreeCtrl(), Item :: integer()) -> ok
Sorts the children of the given item using OnCompareItems() (not implemented in wx).
You should override that method to change the sort order (the default is ascending case-sensitive alphabetical order).
toggle(This :: wxTreeCtrl(), Item :: integer()) -> ok
Toggles the given item between collapsed and expanded states.
toggleItemSelection(This :: wxTreeCtrl(), Item :: integer()) -> ok
Toggles the given item between selected and unselected states.
For multiselection controls only.
unselect(This :: wxTreeCtrl()) -> ok
Removes the selection from the currently selected item (if any).
unselectAll(This :: wxTreeCtrl()) -> ok
This function either behaves the same as unselect/1 if the control doesn't have wxTR\_MULTIPLE
style, or removes the selection from all items if it does have this style.
unselectItem(This :: wxTreeCtrl(), Item :: integer()) -> ok
Unselects the given item.
This works in multiselection controls only.