wxTreeCtrl

wxTreeCtrl

wxTreeCtrl
Functions for wxTreeCtrl class

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:

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: wxDataViewTreeCtrl (not implemented in wx), wxTreeEvent, wxTreeItemData (not implemented in wx), Overview treectrl, wxListBox, wxListCtrl, wxImageList

This class is derived (and can use functions) from: wxControl wxWindow wxEvtHandler

wxWidgets docs: wxTreeCtrl

Destructor, destroying the tree control.

Types

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.

Types

Parent = integer()
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.

Types

Item = integer()

Collapses the given item and removes all children.

Types

Item = integer()

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.

Types

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.

Types

Item = integer()

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.

Types

Item = integer()

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: EndEditLabel() (not implemented in wx), wxTreeEvent

Types

Item = integer()

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).

Types

Result =
    {Res :: boolean(),
     Rect ::
         {X :: integer(),
          Y :: integer(),
          W :: integer(),
          H :: integer()}}
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.

Types

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.

Types

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.

Types

Result = {Res :: integer(), Cookie :: integer()}
Item = integer()

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: getNextChild/3, getNextSibling/2

Types

Result = {Res :: integer(), Cookie :: integer()}
Item = 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

Types

Item = integer()

Returns the tree item data associated with the item.

See: wxTreeItemData (not implemented in wx)

Types

Item = integer()

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.

Types

Item = 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.

Types

Item = 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.

Types

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).

Types

Result = {Res :: integer(), Selection :: [integer()]}

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.

Types

Result = {Res :: integer(), Flags :: integer()}
Point = {X :: integer(), Y :: 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:

Types

Parent = Previous = integer()
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.

Types

Item = integer()

Returns true if the item is expanded (only makes sense if it has children).

Types

Item = integer()

Returns true if the item is valid.

Types

Parent = integer()
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.

Types

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.

Types

Indent = integer()

Sets the indentation for the tree control.

Types

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

Types

Item = integer()
Data = term()

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.

Types

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).

Types

Item = integer()

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

Types

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.

Types

Item = Image = integer()
Option = {which, wx:wx_enum()}

Sets the specified item's image.

See getItemImage/3 for the description of the which parameter.

Types

Styles = integer()

Sets the mode flags associated with the display of the tree control.

The new mode takes effect immediately.

Note: Generic only; MSW ignores changes.

Types

Item = integer()

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).

See: wxTreeItemData (not implemented in wx), OnCompareItems() (not implemented in wx)

Types

Item = integer()

Toggles the given item between collapsed and expanded states.

Types

Item = integer()

Toggles the given item between selected and unselected states.

For multiselection controls only.

Types

Removes the selection from the currently selected item (if any).

Types

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.

Types

Item = integer()

Unselects the given item.

This works in multiselection controls only.