Future Improvements¶

Some features are supported by the native MSW control and so could be easily implemented in this version of wx.HeaderCtrl but need to be implemented in the generic version as well to be really useful. Please let us know if you need or, better, plan to work on implementing, any of them:

• Displaying bitmaps instead of or together with the text

• Custom drawn headers

Window Styles¶

• Filters associated with a column. This class supports the following styles:

  • wx.HD_ALLOW_REORDER: If this style is specified (it is by default), the user can reorder the control columns by dragging them.

  • wx.HD_ALLOW_HIDE: If this style is specified, the control shows a popup menu allowing the user to change the columns visibility on right mouse click. Notice that the program can always hide or show the columns, this style only affects the users capability to do it.

  • wx.HD_BITMAP_ON_RIGHT: The column image, if any, will be shown on the right side if this style is used. Note that this style is only implemented in wxMSW currently and doesn’t do anything under the other platforms. It is available since wxWidgets 3.1.1.

  • wx.HD_DEFAULT_STYLE: Symbolic name for the default control style, currently equal to HD_ALLOW_REORDER .

Events Emitted by this Class¶

Handlers bound for the following event types will receive one of the wx.HeaderCtrlEvent parameters.

• EVT_HEADER_CLICK: A column heading was clicked.

• EVT_HEADER_RIGHT_CLICK: A column heading was right clicked.

• EVT_HEADER_MIDDLE_CLICK: A column heading was clicked with the middle mouse button.

• EVT_HEADER_DCLICK: A column heading was double clicked.

• EVT_HEADER_RIGHT_DCLICK: A column heading was right double clicked.

• EVT_HEADER_MIDDLE_DCLICK: A column heading was double clicked with the middle mouse button.

• EVT_HEADER_SEPARATOR_DCLICK: Separator to the right of the specified column was double clicked (this action is commonly used to resize the column to fit its contents width and the control provides UpdateColumnWidthToFit method to make implementing this easier).

• EVT_HEADER_BEGIN_RESIZE: The user started to drag the separator to the right of the column with the specified index (this can only happen for the columns for which wx.HeaderColumn.IsResizeable returns True). The event can be vetoed to prevent the column from being resized. If it isn’t, the resizing and end resize (or dragging cancelled) events will be generated later.

• EVT_HEADER_RESIZING: The user is dragging the column with the specified index resizing it and its current width is wx.HeaderCtrlEvent.GetWidth . The event can be vetoed to stop the dragging operation completely at any time.

• EVT_HEADER_END_RESIZE: The user stopped dragging the column by releasing the mouse. The column should normally be resized to the value of wx.HeaderCtrlEvent.GetWidth .

• EVT_HEADER_BEGIN_REORDER: The user started to drag the column with the specified index (this can only happen for the controls with wx.HD_ALLOW_REORDER style). This event can be vetoed to prevent the column from being reordered, otherwise the end reorder message will be generated later.

• EVT_HEADER_END_REORDER: The user dropped the column in its new location. The event can be vetoed to prevent the column from being placed at the new position or handled to update the display of the data in the associated control to match the new column location (available from wx.HeaderCtrlEvent.GetNewOrder ).

• EVT_HEADER_DRAGGING_CANCELLED: The resizing or reordering operation currently in progress was cancelled. This can happen if the user pressed Esc key while dragging the mouse or the mouse capture was lost for some other reason. You only need to handle this event if your application entered into some modal mode when resizing or reordering began, in which case it should handle this event in addition to the matching end resizing or reordering ones.

Class Hierarchy¶

Inheritance diagram for class HeaderCtrl:

Known Subclasses¶

wx.HeaderCtrlSimple

Methods Summary¶

Properties Summary¶

Class API¶

class wx.HeaderCtrl(Control)¶

Possible constructors:

HeaderCtrl() -> None

HeaderCtrl(parent, winid=ID_ANY, pos=DefaultPosition, size=DefaultSize,
           style=HD_DEFAULT_STYLE, name=HeaderCtrlNameStr) -> None

HeaderCtrl is the control containing the column headings which is usually used for display of tabular data.

Methods¶

__init__(self, *args, **kw)¶

Overloaded Implementations:

---

__init__ (self)

Default constructor not creating the underlying window.

You must use Create after creating the object using this constructor.

Return type:

None

---

__init__ (self, parent, winid=ID_ANY, pos=DefaultPosition, size=DefaultSize, style=HD_DEFAULT_STYLE, name=HeaderCtrlNameStr)

Constructor creating the window.

Please see Create for the parameters documentation.

Parameters:

• parent (wx.Window)

• winid (wx.WindowID)

• pos (wx.Point)

• size (wx.Size)

• style (long)

• name (string)

Return type:

None

---

---

AddColumnsItems(self, menu, idColumnsBase=0)¶

Helper function appending the checkable items corresponding to all the columns to the given menu.

This function is used by ShowColumnsMenu but can also be used if you show your own custom columns menu and still want all the columns shown in it. It appends menu items with column labels as their text and consecutive ids starting from idColumnsBase to the menu and checks the items corresponding to the currently visible columns.

Example of use:

def ColumnItems(self):

    menu = wx.Menu()
    menu.Append(100, "Some custom command")
    menu.AppendSeparator()
    self.AddColumnsItems(menu, 200)
    rc = self.GetPopupMenuSelectionFromUser(menu, pt)

    if rc >= 200:
        # ... toggle visibility of the column rc-200 ...
        ToggleVisibility()

Parameters:

• menu (wx.Menu) – The menu to append the items to. It may be currently empty or not.

• idColumnsBase (int) – The id for the menu item corresponding to the first column, the other ones are consecutive starting from it. It should be positive.

Return type:

None

---

Create(self, parent, winid=ID_ANY, pos=DefaultPosition, size=DefaultSize, style=HD_DEFAULT_STYLE, name=HeaderCtrlNameStr)¶

Create the header control window.

Parameters:

• parent (wx.Window) – The parent window. The header control should be typically positioned along the top edge of this window.

• winid (wx.WindowID) – Id of the control or ID_ANY if you don’t care.

• pos (wx.Point) – The initial position of the control.

• size (wx.Size) – The initial size of the control (usually not very useful as this control will typically be resized to have the same width as the associated data display control).

• style (long) – The control style, HD_DEFAULT_STYLE by default. Notice that the default style allows the user to reorder the columns by dragging them and you need to explicitly turn this feature off by using:

  wx.HD_DEFAULT_STYLE & ~wx.HD_ALLOW_REORDER
  

  if this is undesirable.

• name (string) – The name of the control.

Return type:

bool

---

static GetClassDefaultAttributes(variant=WINDOW_VARIANT_NORMAL)¶

Parameters:

variant (WindowVariant)

Return type:

wx.VisualAttributes

---

GetColumn(self, idx)¶

Method to be implemented by the derived classes to return the information for the given column.

Parameters:

idx (int) – The column index, between 0 and the value last passed to SetColumnCount .

Return type:

wx.HeaderColumn

---

GetColumnAt(self, pos)¶

Return the index of the column displayed at the given position.

Parameters:

pos (int) – The display position, e.g. 0 for the left-most column, 1 for the next one and so on until GetColumnCount - 1.

Return type:

int

See also

GetColumnPos

---

GetColumnCount(self)¶

Return the number of columns in the control.

Return type:

int

Returns:

Number of columns as previously set by SetColumnCount .

See also

IsEmpty

---

GetColumnPos(self, idx)¶

Get the position at which this column is currently displayed.

Notice that a valid position is returned even for the hidden columns currently.

Parameters:

idx (int) – The column index, must be less than GetColumnCount .

Return type:

int

See also

GetColumnAt

---

GetColumnTitleWidth(self, *args, **kw)¶

Overloaded Implementations:

---

GetColumnTitleWidth (self, col)

Returns width needed for given column’s title.

Parameters:

col (wx.HeaderColumn)

Return type:

int

Added in version 2.9.4.

---

GetColumnTitleWidth (self, idx)

Returns width needed for the column with the given index.

This is just a convenient wrapper for the overload taking wx.HeaderColumn.

Parameters:

idx (int)

Return type:

int

Added in version 4.1/wxWidgets-3.1.3.

---

---

GetColumnsOrder(self)¶

Return the array describing the columns display order.

For the controls without wx.HD_ALLOW_REORDER style the returned array will be the same as was passed to SetColumnsOrder previously or define the default order (with n-th element being n) if it hadn’t been called. But for the controls with wx.HD_ALLOW_REORDER style, the columns can be also reordered by user.

Return type:

List[int]

---

IsEmpty(self)¶

Return whether the control has any columns.

Return type:

bool

See also

GetColumnCount

---

static MoveColumnInOrderArray(order, idx, pos)¶

Helper function to manipulate the array of column indices.

This function reshuffles the array of column indices indexed by positions (i.e. using the same convention as for SetColumnsOrder ) so that the column with the given index is found at the specified position.

Parameters:

• order (list of integers) – Array containing the indices of columns in order of their positions.

• idx (int) – The index of the column to move.

• pos (int) – The new position for the column idx.

Return type:

None

---

OnColumnCountChanging(self, count)¶

Can be overridden in the derived class to update internal data structures when the number of the columns in the control changes.

This method is called by SetColumnCount before effectively changing the number of columns.

The base class version does nothing but it is good practice to still call it from the overridden version in the derived class.

Parameters:

count (int)

Return type:

None

---

ResetColumnsOrder(self)¶

Reset the columns order to the natural one.

After calling this function, the column with index idx appears at position idx in the control.

Return type:

None

---

SetColumnCount(self, count)¶

Set the number of columns in the control.

The control will use GetColumn to get information about all the new columns and refresh itself, i.e. this method also has the same effect as calling UpdateColumn for all columns but it should only be used if the number of columns really changed.

Parameters:

count (int)

Return type:

None

---

SetColumnsOrder(self, order)¶

Change the columns display order.

The display order defines the order in which the columns appear on the screen and does not affect the interpretation of indices by all the other class methods.

The order array specifies the column indices corresponding to the display positions.

Parameters:

order (list of integers) – A permutation of all column indices, i.e. an array of size GetColumnsOrder containing all column indices exactly once. The n-th element of this array defines the index of the column shown at the n-th position from left (for the default left-to-right writing direction).

Return type:

None

See also

wx.ListCtrl.SetColumnsOrder

---

ShowColumnsMenu(self, pt, title='')¶

Show the popup menu allowing the user to show or hide the columns.

This functions shows the popup menu containing all columns with check marks for the ones which are currently shown and allows the user to check or uncheck them to toggle their visibility. It is called from the default EVT_HEADER_RIGHT_CLICK handler for the controls which have wx.HD_ALLOW_HIDE style. And if the column has wx.HD_ALLOW_REORDER style as well, the menu also contains an item to customize the columns shown using which results in ShowCustomizeDialog being called, please see its description for more details.

If a column was toggled, UpdateColumnVisibility virtual function is called so it must be implemented for the controls with wx.HD_ALLOW_HIDE style or if you call this function explicitly.

Parameters:

• pt (wx.Point) – The position of the menu, in the header window coordinates.

• title (string) – The title for the menu if not empty.

Return type:

bool

Returns:

True if a column was shown or hidden or False if nothing was done, e.g. because the menu was cancelled.

---

ShowCustomizeDialog(self)¶

Show the column customization dialog.

This function displays a modal dialog containing the list of all columns which the user can use to reorder them as well as show or hide individual columns.

If the user accepts the changes done in the dialog, the virtual methods UpdateColumnVisibility and UpdateColumnsOrder will be called so they must be overridden in the derived class if this method is ever called. Please notice that the user will be able to invoke it interactively from the header popup menu if the control has both wx.HD_ALLOW_HIDE and wx.HD_ALLOW_REORDER styles.

Return type:

bool

See also

wx.RearrangeDialog

---

UpdateColumn(self, idx)¶

Update the column with the given index.

When the value returned by GetColumn changes, this method must be called to notify the control about the change and update the visual display to match the new column data.

Parameters:

idx (int) – The column index, must be less than GetColumnCount .

Return type:

None

---

UpdateColumnVisibility(self, idx, show)¶

Method called when the column visibility is changed by the user.

This method is called from ShowColumnsMenu or ShowCustomizeDialog when the user interactively hides or shows a column. A typical implementation will simply update the internally stored column state. Notice that there is no need to call UpdateColumn from this method as it is already done by wx.HeaderCtrl itself.

The base class version doesn’t do anything and must be overridden if this method is called.

Parameters:

• idx (int) – The index of the column whose visibility was toggled.

• show (bool) – The new visibility value, True if the column is now shown or False if it is not hidden.

Return type:

None

---

UpdateColumnWidthToFit(self, idx, widthTitle)¶

Method which may be implemented by the derived classes to allow double clicking the column separator to resize the column to fit its contents.

When a separator is double clicked, the default handler of EVT_HEADER_SEPARATOR_DCLICK event calls this function and refreshes the column if it returns True so to implement the resizing of the column to fit its width on header double click you need to implement this method using logic similar to this example:

class MyHeaderColumn(wx.HeaderColumn):

    def __init__(self):

        wx.HeaderColumn.__init__(self)


    def SetWidth(self, width):

        self.width = width


    def GetWidth(self):

        return self.width


class MyHeaderCtrl(wx.HeaderCtrl):

    def __init__(self, parent):

        wx.HeaderCtrl.__init__(self, parent)
        self.cols = []


    def GetColumn(idx):

        return self.cols[idx]


    def UpdateColumnWidthToFit(self, idx, widthTitle):

        # ... compute minimal width for column idx ...
        widthContents = self.CalculateMinWidth(idx)
        self.cols[idx].SetWidth(max(widthContents, widthTitle))

        return True

Base class version simply returns False.

Parameters:

• idx (int) – The zero-based index of the column to update.

• widthTitle (int) – Contains minimal width needed to display the column header itself and will usually be used as a starting point for the fitting width calculation.

Return type:

bool

Returns:

True to indicate that the column was resized, i.e. GetColumn now returns the new width value, and so must be refreshed or False meaning that the control didn’t reach to the separator double click.

---

UpdateColumnsOrder(self, order)¶

Method called when the columns order is changed in the customization dialog or when the EVT_HEADER_END_REORDER event is not handled after dragging a single column.

This method is always called from ShowCustomizeDialog when the user changes the order of columns. In case a single column changes place because the user dragged it to a new location, the EVT_HEADER_END_REORDER event handler can be used to react to this. If this event handler is not defined though UpdateColumnsOrder will be called instead.

A typical implementation in a derived class will update the display order of the columns in the associated control, if any. Notice that there is no need to call SetColumnsOrder from it as wx.HeaderCtrl does it itself.

The base class version doesn’t do anything and must be overridden if this method is called.

Parameters:

order (list of integers) – The new column order. This array uses the same convention as SetColumnsOrder .

Return type:

None

Properties¶

ColumnCount¶

See GetColumnCount and SetColumnCount

---

ColumnsOrder¶

See GetColumnsOrder and SetColumnsOrder