interface/wx/headerctrl.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/headerctrl.h
   3 // Purpose:     interface of wxHeaderCtrl
   4 // Author:      Vadim Zeitlin
   5 // Created:     2008-12-01
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2008 Vadim Zeitlin <vadim@wxwidgets.org>
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 /**
  12     @class wxHeaderCtrl
  13
  14     wxHeaderCtrl is the control containing the column headings which is usually
  15     used for display of tabular data.
  16
  17     It is used as part of wxGrid, in generic version wxDataViewCtrl and report
  18     view of wxListCtrl but can be also used independently. In general this
  19     class is meant to be used as part of another control which already stores
  20     the column information somewhere as it can't be used directly: instead you
  21     need to inherit from it and implement the GetColumn() method to provide
  22     column information. See wxHeaderCtrlSimple for a concrete control class
  23     which can be used directly.
  24
  25     In addition to labeling the columns, the control has the following
  26     features:
  27         - Column reordering support, either by explicitly configuring the
  28           columns order and calling SetColumnsOrder() or by dragging the
  29           columns interactively (if enabled).
  30         - Display of the icons in the header: this is often used to display a
  31           sort or reverse sort indicator when the column header is clicked.
  32
  33     Notice that this control itself doesn't do anything other than displaying
  34     the column headers. In particular column reordering and sorting must still
  35     be supported by the associated control displaying the real data under the
  36     header. Also remember to call ScrollWindow() method of the control if the
  37     associated data display window has a horizontal scrollbar, otherwise the
  38     headers wouldn't align with the data when the window is scrolled.
  39
  40     This control is implemented using the native header control under MSW
  41     systems and a generic implementation elsewhere.
  42
  43
  44     @section headerctrl_improvements Future Improvements
  45
  46     Some features are supported by the native MSW control and so could be
  47     easily implemented in this version of wxHeaderCtrl but need to be
  48     implemented in the generic version as well to be really useful. Please let
  49     us know if you need or, better, plan to work on implementing, any of them:
  50         - Displaying bitmaps instead of or together with the text
  51         - Custom drawn headers
  52         - Filters associated with a column.
  53
  54
  55     @beginStyleTable
  56     @style{wxHD_ALLOW_REORDER}
  57         If this style is specified (it is by default), the user can reorder
  58         the control columns by dragging them.
  59     @style{wxHD_ALLOW_HIDE}
  60         If this style is specified, the control shows a popup menu allowing the
  61         user to change the columns visibility on right mouse click. Notice that
  62         the program can always hide or show the columns, this style only
  63         affects the users capability to do it.
  64     @style{wxHD_DEFAULT_STYLE}
  65         Symbolic name for the default control style, currently equal to
  66         @c wxHD_ALLOW_REORDER.
  67     @endStyleTable
  68
  69     @beginEventEmissionTable{wxHeaderCtrlEvent}
  70     @event{EVT_HEADER_CLICK(id, func)}
  71         A column heading was clicked.
  72     @event{EVT_HEADER_RIGHT_CLICK(id, func)}
  73         A column heading was right clicked.
  74     @event{EVT_HEADER_MIDDLE_CLICK(id, func)}
  75         A column heading was clicked with the middle mouse button.
  76     @event{EVT_HEADER_DCLICK(id, func)}
  77         A column heading was double clicked.
  78     @event{EVT_HEADER_RIGHT_DCLICK(id, func)}
  79         A column heading was right double clicked.
  80     @event{EVT_HEADER_MIDDLE_DCLICK(id, func)}
  81         A column heading was double clicked with the middle mouse button.
  82     @event{EVT_HEADER_SEPARATOR_DCLICK(id, func)}
  83         Separator to the right of the specified column was double clicked
  84         (this action is commonly used to resize the column to fit its
  85         contents width and the control provides UpdateColumnWidthToFit() method
  86         to make implementing this easier).
  87     @event{EVT_HEADER_BEGIN_RESIZE(id, func)}
  88         The user started to drag the separator to the right of the column
  89         with the specified index (this can only happen for the columns for
  90         which wxHeaderColumn::IsResizeable() returns true). The event can
  91         be vetoed to prevent the column from being resized. If it isn't,
  92         the resizing and end resize (or dragging cancelled) events will be
  93         generated later.
  94     @event{EVT_HEADER_RESIZING(id, func)}
  95         The user is dragging the column with the specified index resizing
  96         it and its current width is wxHeaderCtrlEvent::GetWidth().
  97         The event can be vetoed to stop the dragging operation completely at
  98         any time.
  99     @event{EVT_HEADER_END_RESIZE(id, func)}
 100         The user stopped dragging the column by releasing the mouse.
 101         The column should normally be resized to the value of
 102         wxHeaderCtrlEvent::GetWidth().
 103     @event{EVT_HEADER_BEGIN_REORDER(id, func)}
 104         The user started to drag the column with the specified index (this
 105         can only happen for the controls with wxHD_ALLOW_REORDER style).
 106         This event can be vetoed to prevent the column from being reordered,
 107         otherwise the end reorder message will be generated later.
 108     @event{EVT_HEADER_END_REORDER(id, func)}
 109         The user dropped the column in its new location. The event can be
 110         vetoed to prevent the column from being placed at the new position
 111         or handled to update the display of the data in the associated
 112         control to match the new column location (available from
 113         wxHeaderCtrlEvent::GetNewOrder()).
 114     @event{EVT_HEADER_DRAGGING_CANCELLED(id, func)}
 115         The resizing or reordering operation currently in progress was
 116         cancelled. This can happen if the user pressed Esc key while
 117         dragging the mouse or the mouse capture was lost for some other
 118         reason. You only need to handle this event if your application
 119         entered into some modal mode when resizing or reordering began, in
 120         which case it should handle this event in addition to the matching
 121         end resizing or reordering ones.
 122     @endEventTable
 123
 124     @library{wxcore}
 125     @category{ctrl}
 126
 127     @see wxGrid, wxListCtrl, wxDataViewCtrl
 128 */
 129 class wxHeaderCtrl : public wxControl
 130 {
 131 public:
 132     /**
 133         Default constructor not creating the underlying window.
 134
 135         You must use Create() after creating the object using this constructor.
 136      */
 137     wxHeaderCtrl();
 138
 139     /**
 140         Constructor creating the window.
 141
 142         Please see Create() for the parameters documentation.
 143      */
 144     wxHeaderCtrl(wxWindow *parent,
 145                  wxWindowID winid = wxID_ANY,
 146                  const wxPoint& pos = wxDefaultPosition,
 147                  const wxSize& size = wxDefaultSize,
 148                  long style = wxHD_DEFAULT_STYLE,
 149                  const wxString& name = wxHeaderCtrlNameStr);
 150
 151     /**
 152         Create the header control window.
 153
 154         @param parent
 155             The parent window. The header control should be typically
 156             positioned along the top edge of this window.
 157         @param winid
 158             Id of the control or @c wxID_ANY if you don't care.
 159         @param pos
 160             The initial position of the control.
 161         @param size
 162             The initial size of the control (usually not very useful as this
 163             control will typically be resized to have the same width as the
 164             associated data display control).
 165         @param style
 166             The control style, @c wxHD_DEFAULT_STYLE by default. Notice that
 167             the default style allows the user to reorder the columns by
 168             dragging them and you need to explicitly turn this feature off by
 169             using @code wxHD_DEFAULT_STYLE & ~wxHD_ALLOW_REORDER @endcode if
 170             this is undesirable.
 171         @param name
 172             The name of the control.
 173      */
 174     bool Create(wxWindow *parent,
 175                 wxWindowID winid = wxID_ANY,
 176                 const wxPoint& pos = wxDefaultPosition,
 177                 const wxSize& size = wxDefaultSize,
 178                 long style = wxHD_DEFAULT_STYLE,
 179                 const wxString& name = wxHeaderCtrlNameStr);
 180
 181     /**
 182         Set the number of columns in the control.
 183
 184         The control will use GetColumn() to get information about all the
 185         new columns and refresh itself, i.e. this method also has the same
 186         effect as calling UpdateColumn() for all columns but it should only be
 187         used if the number of columns really changed.
 188      */
 189     void SetColumnCount(unsigned int count);
 190
 191     /**
 192         Return the number of columns in the control.
 193
 194         @return
 195             Number of columns as previously set by SetColumnCount().
 196
 197         @see IsEmpty()
 198      */
 199     unsigned int GetColumnCount() const;
 200
 201     /**
 202         Return whether the control has any columns.
 203
 204         @see GetColumnCount()
 205      */
 206     bool IsEmpty() const;
 207
 208     /**
 209         Update the column with the given index.
 210
 211         When the value returned by GetColumn() changes, this method must be
 212         called to notify the control about the change and update the visual
 213         display to match the new column data.
 214
 215         @param idx
 216             The column index, must be less than GetColumnCount().
 217      */
 218     void UpdateColumn(unsigned int idx);
 219
 220     /**
 221         Change the columns display order.
 222
 223         The display order defines the order in which the columns appear on the
 224         screen and does @em not affect the interpretation of indices by all the
 225         other class methods.
 226
 227         The @a order array specifies the column indices corresponding to the
 228         display positions.
 229
 230         @param order
 231             A permutation of all column indices, i.e. an array of size
 232             GetColumnsOrder() containing all column indices exactly once. The
 233             n-th element of this array defines the index of the column shown at
 234             the n-th position from left (for the default left-to-right writing
 235             direction).
 236
 237         @see wxListCtrl::SetColumnsOrder()
 238      */
 239     void SetColumnsOrder(const wxArrayInt& order);
 240
 241     /**
 242         Return the array describing the columns display order.
 243
 244         For the controls without wxHD_ALLOW_REORDER style the returned array
 245         will be the same as was passed to SetColumnsOrder() previously or
 246         define the default order (with n-th element being n) if it hadn't been
 247         called. But for the controls with wxHD_ALLOW_REORDER style, the columns
 248         can be also reordered by user.
 249      */
 250     wxArrayInt GetColumnsOrder() const;
 251
 252     /**
 253         Return the index of the column displayed at the given position.
 254
 255         @param pos
 256             The display position, e.g. 0 for the left-most column, 1 for the
 257             next one and so on until GetColumnCount() - 1.
 258
 259         @see GetColumnPos()
 260      */
 261     unsigned int GetColumnAt(unsigned int pos) const;
 262
 263     /**
 264         Get the position at which this column is currently displayed.
 265
 266         Notice that a valid position is returned even for the hidden columns
 267         currently.
 268
 269         @param idx
 270             The column index, must be less than GetColumnCount().
 271
 272         @see GetColumnAt()
 273      */
 274     unsigned int GetColumnPos(unsigned int idx) const;
 275
 276     /**
 277         Reset the columns order to the natural one.
 278
 279         After calling this function, the column with index @c idx appears at
 280         position @c idx in the control.
 281      */
 282     void ResetColumnsOrder();
 283
 284     /**
 285         Helper function to manipulate the array of column indices.
 286
 287         This function reshuffles the array of column indices indexed by
 288         positions (i.e. using the same convention as for SetColumnsOrder()) so
 289         that the column with the given index is found at the specified
 290         position.
 291
 292         @param order
 293             Array containing the indices of columns in order of their
 294             positions.
 295         @param idx
 296             The index of the column to move.
 297         @param pos
 298             The new position for the column @a idx.
 299      */
 300     static void MoveColumnInOrderArray(wxArrayInt& order,
 301                                        unsigned int idx,
 302                                        unsigned int pos);
 303
 304     /**
 305         Show the popup menu allowing the user to show or hide the columns.
 306
 307         This functions shows the popup menu containing all columns with check
 308         marks for the ones which are currently shown and allows the user to
 309         check or uncheck them to toggle their visibility. It is called from the
 310         default EVT_HEADER_RIGHT_CLICK handler for the controls which have
 311         wxHD_ALLOW_HIDE style. And if the column has wxHD_ALLOW_REORDER style
 312         as well, the menu also contains an item to customize the columns shown
 313         using which results in ShowCustomizeDialog() being called, please see
 314         its description for more details.
 315
 316         If a column was toggled, UpdateColumnVisibility() virtual function is
 317         called so it must be implemented for the controls with wxHD_ALLOW_HIDE
 318         style or if you call this function explicitly.
 319
 320         @param pt
 321             The position of the menu, in the header window coordinates.
 322         @param title
 323             The title for the menu if not empty.
 324         @return
 325             @true if a column was shown or hidden or @false if nothing was
 326             done, e.g. because the menu was cancelled.
 327      */
 328     bool ShowColumnsMenu(const wxPoint& pt, const wxString& title = wxString());
 329
 330     /**
 331         Helper function appending the checkable items corresponding to all the
 332         columns to the given menu.
 333
 334         This function is used by ShowColumnsMenu() but can also be used if you
 335         show your own custom columns menu and still want all the columns shown
 336         in it. It appends menu items with column labels as their text and
 337         consecutive ids starting from @a idColumnsBase to the menu and checks
 338         the items corresponding to the currently visible columns.
 339
 340         Example of use:
 341         @code
 342             wxMenu menu;
 343             menu.Append(100, "Some custom command");
 344             menu.AppendSeparator();
 345             AddColumnsItems(menu, 200);
 346             const int rc = GetPopupMenuSelectionFromUser(menu, pt);
 347             if ( rc >= 200 )
 348                 ... toggle visibility of the column rc-200 ...
 349         @endcode
 350
 351         @param menu
 352             The menu to append the items to. It may be currently empty or not.
 353         @param idColumnsBase
 354             The id for the menu item corresponding to the first column, the
 355             other ones are consecutive starting from it. It should be positive.
 356      */
 357     void AddColumnsItems(wxMenu& menu, int idColumnsBase = 0);
 358
 359     /**
 360         Show the column customization dialog.
 361
 362         This function displays a modal dialog containing the list of all
 363         columns which the user can use to reorder them as well as show or hide
 364         individual columns.
 365
 366         If the user accepts the changes done in the dialog, the virtual
 367         methods UpdateColumnVisibility() and UpdateColumnsOrder() will be
 368         called so they must be overridden in the derived class if this method
 369         is ever called. Please notice that the user will be able to invoke it
 370         interactively from the header popup menu if the control has both
 371         wxHD_ALLOW_HIDE and wxHD_ALLOW_REORDER styles.
 372
 373         @see wxRearrangeDialog
 374      */
 375     bool ShowCustomizeDialog();
 376
 377     /**
 378         Returns width needed for given column's title.
 379
 380         @since 2.9.4
 381      */
 382     int GetColumnTitleWidth(const wxHeaderColumn& col);
 383
 384 protected:
 385     /**
 386         Method to be implemented by the derived classes to return the
 387         information for the given column.
 388
 389         @param idx
 390             The column index, between 0 and the value last passed to
 391             SetColumnCount().
 392      */
 393     virtual const wxHeaderColumn& GetColumn(unsigned int idx) const = 0;
 394
 395     /**
 396         Method called when the column visibility is changed by the user.
 397
 398         This method is called from ShowColumnsMenu() or ShowCustomizeDialog()
 399         when the user interactively hides or shows a column. A typical
 400         implementation will simply update the internally stored column state.
 401         Notice that there is no need to call UpdateColumn() from this method as
 402         it is already done by wxHeaderCtrl itself.
 403
 404         The base class version doesn't do anything and must be overridden if
 405         this method is called.
 406
 407         @param idx
 408             The index of the column whose visibility was toggled.
 409         @param show
 410             The new visibility value, @true if the column is now shown or
 411             @false if it is not hidden.
 412      */
 413     virtual void UpdateColumnVisibility(unsigned int idx, bool show);
 414
 415     /**
 416         Method called when the columns order is changed in the customization
 417         dialog.
 418
 419         This method is only called from ShowCustomizeDialog() when the user
 420         changes the order of columns. In particular it is @em not called if a
 421         single column changes place because the user dragged it to the new
 422         location, the EVT_HEADER_END_REORDER event handler should be used to
 423         react to this.
 424
 425         A typical implementation in a derived class will update the display
 426         order of the columns in the associated control, if any. Notice that
 427         there is no need to call SetColumnsOrder() from it as wxHeaderCtrl does
 428         it itself.
 429
 430         The base class version doesn't do anything and must be overridden if
 431         this method is called.
 432
 433         @param order
 434             The new column order. This array uses the same convention as
 435             SetColumnsOrder().
 436      */
 437     virtual void UpdateColumnsOrder(const wxArrayInt& order);
 438
 439     /**
 440         Method which may be implemented by the derived classes to allow double
 441         clicking the column separator to resize the column to fit its contents.
 442
 443         When a separator is double clicked, the default handler of
 444         EVT_HEADER_SEPARATOR_DCLICK event calls this function and refreshes the
 445         column if it returns @true so to implement the resizing of the column
 446         to fit its width on header double click you need to implement this
 447         method using logic similar to this example:
 448         @code
 449             class MyHeaderColumn : public wxHeaderColumn
 450             {
 451             public:
 452                 ...
 453
 454                 void SetWidth(int width) { m_width = width; }
 455                 virtual int GetWidth() const { return m_width; }
 456
 457             private:
 458                 int m_width;
 459             };
 460
 461             class MyHeaderCtrl : public wxHeaderCtrl
 462             {
 463             public:
 464             protected:
 465                 virtual wxHeaderColumn& GetColumn(unsigned int idx) const
 466                 {
 467                     return m_cols[idx];
 468                 }
 469
 470                 virtual bool UpdateColumnWidthToFit(unsigned int idx, int widthTitle)
 471                 {
 472                     int widthContents = ... compute minimal width for column idx ...
 473                     m_cols[idx].SetWidth(wxMax(widthContents, widthTitle));
 474                     return true;
 475                 }
 476
 477                 wxVector<MyHeaderColumn> m_cols;
 478             };
 479         @endcode
 480
 481         Base class version simply returns @false.
 482
 483         @param idx
 484             The zero-based index of the column to update.
 485         @param widthTitle
 486             Contains minimal width needed to display the column header itself
 487             and will usually be used as a starting point for the fitting width
 488             calculation.
 489
 490         @return
 491             @true to indicate that the column was resized, i.e. GetColumn() now
 492             returns the new width value, and so must be refreshed or @false
 493             meaning that the control didn't reach to the separator double click.
 494      */
 495     virtual bool UpdateColumnWidthToFit(unsigned int idx, int widthTitle);
 496
 497     /**
 498         Can be overridden in the derived class to update internal data
 499         structures when the number of the columns in the control changes.
 500
 501         This method is called by SetColumnCount() before effectively changing
 502         the number of columns.
 503
 504         The base class version does nothing but it is good practice to still
 505         call it from the overridden version in the derived class.
 506      */
 507     virtual void OnColumnCountChanging(unsigned int count);
 508 };
 509
 510
 511 /**
 512     @class wxHeaderCtrlSimple
 513
 514     wxHeaderCtrlSimple is a concrete header control which can be used directly,
 515     without inheriting from it as you need to do when using wxHeaderCtrl
 516     itself.
 517
 518     When using it, you need to use simple AppendColumn(), InsertColumn() and
 519     DeleteColumn() methods instead of setting the number of columns with
 520     SetColumnCount() and returning the information about them from the
 521     overridden GetColumn().
 522
 523     @library{wxcore}
 524     @category{ctrl}
 525
 526     @see wxHeaderCtrl
 527 */
 528 class wxHeaderCtrlSimple : public wxHeaderCtrl
 529 {
 530 public:
 531     /**
 532         Default constructor not creating the underlying window.
 533
 534         You must use Create() after creating the object using this constructor.
 535      */
 536     wxHeaderCtrlSimple();
 537
 538     /**
 539         Constructor creating the window.
 540
 541         Please see the base class wxHeaderCtrl::Create() method for the
 542         parameters description.
 543      */
 544     wxHeaderCtrlSimple(wxWindow *parent,
 545                        wxWindowID winid = wxID_ANY,
 546                        const wxPoint& pos = wxDefaultPosition,
 547                        const wxSize& size = wxDefaultSize,
 548                        long style = wxHD_DEFAULT_STYLE,
 549                        const wxString& name = wxHeaderCtrlNameStr);
 550
 551     /**
 552         Insert the column at the given position.
 553
 554         @param col
 555             The column to insert. Notice that because of the existence of
 556             implicit conversion from wxString to wxHeaderColumn a string
 557             can be passed directly here.
 558         @param idx
 559             The position of the new column, from 0 to GetColumnCount(). Using
 560             GetColumnCount() means to append the column to the end.
 561
 562         @see AppendColumn()
 563      */
 564     void InsertColumn(const wxHeaderColumnSimple& col, unsigned int idx);
 565
 566     /**
 567         Append the column to the end of the control.
 568
 569         @see InsertColumn()
 570      */
 571     void AppendColumn(const wxHeaderColumnSimple& col);
 572
 573     /**
 574         Delete the column at the given position.
 575
 576         @see InsertColumn(), AppendColumn()
 577      */
 578     void DeleteColumn(unsigned int idx);
 579
 580     /**
 581         Show or hide the column.
 582
 583         Initially the column is shown by default or hidden if it was added with
 584         wxCOL_HIDDEN flag set.
 585
 586         When a column is hidden, it doesn't appear at all on the screen but its
 587         index is still taken into account when working with other columns. E.g.
 588         if there are three columns 0, 1 and 2 and the column 1 is hidden you
 589         still need to use index 2 to refer to the last visible column.
 590
 591         @param idx
 592             The index of the column to show or hide, from 0 to GetColumnCount().
 593         @param show
 594             Indicates whether the column should be shown (default) or hidden.
 595      */
 596     void ShowColumn(unsigned int idx, bool show = true);
 597
 598     /**
 599         Hide the column with the given index.
 600
 601         This is the same as calling @code ShowColumn(idx, false) @endcode.
 602
 603         @param idx
 604             The index of the column to show or hide, from 0 to GetColumnCount().
 605      */
 606     void HideColumn(unsigned int idx);
 607
 608     /**
 609         Update the column sort indicator.
 610
 611         The sort indicator, if shown, is typically an arrow pointing upwards or
 612         downwards depending on whether the control contents is sorted in
 613         ascending or descending order.
 614
 615         @param idx
 616             The column to set the sort indicator for.
 617             If @c -1 is given, then the currently shown sort indicator
 618             will be removed.
 619         @param sortOrder
 620             If @true or @false show the sort indicator corresponding to
 621             ascending or descending sort order respectively.
 622      */
 623     void ShowSortIndicator(unsigned int idx, bool sortOrder = true);
 624
 625     /**
 626         Remove the sort indicator from the column being used as sort key.
 627
 628         @see ShowSortIndicator
 629      */
 630     void RemoveSortIndicator();
 631
 632 protected:
 633     /**
 634         This function can be overridden in the classes deriving from this
 635         control instead of overriding UpdateColumnWidthToFit().
 636
 637         To implement automatic column resizing to fit its contents width when
 638         the column divider is double clicked, you need to simply return the
 639         fitting width for the given column @a idx from this method, the control
 640         will automatically use the biggest value between the one returned from
 641         here and the one needed for the display of the column title itself.
 642
 643         The base class version returns -1 indicating that this function is not
 644         implemented.
 645      */
 646     virtual int GetBestFittingWidth(unsigned int idx) const;
 647 };
 648
 649 /**
 650     @class wxHeaderCtrlEvent
 651
 652     Event class representing the events generated by wxHeaderCtrl.
 653
 654     @library{wxcore}
 655     @category{events}
 656
 657     @see wxHeaderCtrl
 658 */
 659 class wxHeaderCtrlEvent : public wxNotifyEvent
 660 {
 661 public:
 662     /**
 663         Return the index of the column affected by this event.
 664
 665         This method can be called for all header control events.
 666      */
 667     int GetColumn() const;
 668
 669     /**
 670         Return the current width of the column.
 671
 672         This method can only be called for the dragging events.
 673      */
 674     int GetWidth() const;
 675
 676     /**
 677         Return the new order of the column.
 678
 679         This method can only be called for end reorder event for which it
 680         indicates the tentative new position for the column GetColumn()
 681         selected by the user. If the event is not vetoed, this will become the
 682         new column position in wxHeaderCtrl::GetColumnsOrder().
 683      */
 684     unsigned int GetNewOrder() const;
 685 };