1 /////////////////////////////////////////////////////////////////////////////
3 // Purpose: interface of wxLayoutAlgorithm
4 // Author: wxWidgets team
6 // Licence: wxWindows license
7 /////////////////////////////////////////////////////////////////////////////
10 @class wxLayoutAlgorithm
13 wxLayoutAlgorithm implements layout of subwindows in MDI or SDI frames.
14 It sends a wxCalculateLayoutEvent event
15 to children of the frame, asking them for information about
16 their size. For MDI parent frames, the algorithm allocates
17 the remaining space to the MDI client window (which contains the MDI child
19 For SDI (normal) frames, a 'main' window is specified as taking up the
22 Because the event system is used, this technique can be applied to any windows,
23 which are not necessarily 'aware' of the layout classes (no virtual functions
24 in wxWindow refer to wxLayoutAlgorithm or its events). However, you
25 may wish to use wxSashLayoutWindow for your subwindows
26 since this class provides handlers for the required events, and accessors
27 to specify the desired size of the window. The sash behaviour in the base class
28 can be used, optionally, to make the windows user-resizable.
30 wxLayoutAlgorithm is typically used in IDE (integrated development environment)
32 where there are several resizable windows in addition to the MDI client window,
34 other primary editing window. Resizable windows might include toolbars, a
36 window, and a window for displaying error and warning messages.
38 When a window receives an OnCalculateLayout event, it should call SetRect in
39 the given event object, to be the old supplied rectangle minus whatever space
41 window takes up. It should also set its own size accordingly.
42 wxSashLayoutWindow::OnCalculateLayout generates an OnQueryLayoutInfo event
43 which it sends to itself to determine the orientation, alignment and size of
45 which it gets from internal member variables set by the application.
47 The algorithm works by starting off with a rectangle equal to the whole frame
49 It iterates through the frame children, generating OnCalculateLayout events
51 the window size and return the remaining rectangle for the next window to
53 is assumed (by wxSashLayoutWindow::OnCalculateLayout) that a window stretches
55 of the frame client, according to the orientation it specifies. For example, a
57 will stretch the full width of the remaining portion of the frame client area.
58 In the other orientation, the window will be fixed to whatever size was
60 OnQueryLayoutInfo. An alignment setting will make the window 'stick' to the
62 bottom of the remaining client area. This scheme implies that order of window
63 creation is important.
64 Say you wish to have an extra toolbar at the top of the frame, a project window
66 the MDI client window, and an output window above the status bar. You should
68 the windows in this order: toolbar, output window, project window. This ensures
70 output window take up space at the top and bottom, and then the remaining
71 height in-between is used for
74 wxLayoutAlgorithm is quite independent of the way in which
75 OnCalculateLayout chooses to interpret a window's size and alignment. Therefore
77 could implement a different window class with a new OnCalculateLayout event
79 that has a more sophisticated way of laying out the windows. It might allow
80 specification of whether stretching occurs in the specified orientation, for
82 rather than always assuming stretching. (This could, and probably should, be
86 @e Note: wxLayoutAlgorithm has nothing to do with wxLayoutConstraints. It is an
88 way of specifying layouts for which the normal constraint system is unsuitable.
93 @see wxSashEvent, wxSashLayoutWindow, @ref overview_eventhandlingoverview
95 class wxLayoutAlgorithm
: public wxObject
106 ~wxLayoutAlgorithm();
109 Lays out the children of a normal frame. @a mainWindow is set to occupy the
111 This function simply calls LayoutWindow().
113 bool LayoutFrame(wxFrame
* frame
, wxWindow
* mainWindow
= NULL
) const;
116 Lays out the children of an MDI parent frame. If @a rect is non-@NULL, the
117 given rectangle will be used as a starting point instead of the frame's client
119 The MDI client window is set to occupy the remaining space.
121 bool LayoutMDIFrame(wxMDIParentFrame
* frame
, wxRect
* rect
= NULL
) const;
124 Lays out the children of a normal frame or other window.
125 @a mainWindow is set to occupy the remaining space. If this is not specified,
127 the last window that responds to a calculate layout event in query mode will
128 get the remaining space
129 (that is, a non-query OnCalculateLayout event will not be sent to this window
130 and the window will be set
131 to the remaining size).
133 bool LayoutWindow(wxWindow
* parent
, wxWindow
* mainWindow
= NULL
) const;
139 @class wxSashLayoutWindow
142 wxSashLayoutWindow responds to OnCalculateLayout events generated
143 by wxLayoutAlgorithm. It allows the
144 application to use simple accessors to specify how the window should be
145 laid out, rather than having to respond to events. The fact that
146 the class derives from wxSashWindow allows sashes to be used if required,
147 to allow the windows to be user-resizable.
149 The documentation for wxLayoutAlgorithm explains
150 the purpose of this class in more detail.
155 @see wxLayoutAlgorithm, wxSashWindow, @ref overview_eventhandlingoverview
157 class wxSashLayoutWindow
: public wxSashWindow
162 Constructs a sash layout window, which can be a child of a frame, dialog or any
163 other non-control window.
166 Pointer to a parent window.
168 Window identifier. If -1, will automatically create an identifier.
170 Window position. wxDefaultPosition is (-1, -1) which indicates that
172 should generate a default position for the window. If using the
173 wxSashLayoutWindow class directly, supply
176 Window size. wxDefaultSize is (-1, -1) which indicates that
178 should generate a default size for the window.
180 Window style. For window styles, please see wxSashLayoutWindow.
184 wxSashLayoutWindow();
185 wxSashLayoutWindow(wxSashLayoutWindow
* parent
, wxWindowID id
,
186 const wxPoint
& pos
= wxDefaultPosition
,
187 const wxSize
& size
= wxDefaultSize
,
188 long style
= wxCLIP_CHILDREN
| wxSW_3D
,
189 const wxString
& name
= "layoutWindow");
193 Initializes a sash layout window, which can be a child of a frame, dialog or
194 any other non-control window.
197 Pointer to a parent window.
199 Window identifier. If -1, will automatically create an identifier.
201 Window position. wxDefaultPosition is (-1, -1) which indicates that
203 should generate a default position for the window. If using the
204 wxSashLayoutWindow class directly, supply
207 Window size. wxDefaultSize is (-1, -1) which indicates that
209 should generate a default size for the window.
211 Window style. For window styles, please see wxSashLayoutWindow.
215 bool Create(wxSashLayoutWindow
* parent
, wxWindowID id
,
216 const wxPoint
& pos
= wxDefaultPosition
,
217 const wxSize
& size
= wxDefaultSize
,
218 long style
= wxCLIP_CHILDREN
| wxSW_3D
,
219 const wxString
& name
= "layoutWindow");
222 Returns the alignment of the window: one of wxLAYOUT_TOP, wxLAYOUT_LEFT,
223 wxLAYOUT_RIGHT, wxLAYOUT_BOTTOM.
225 wxLayoutAlignment
GetAlignment() const;
228 Returns the orientation of the window: one of wxLAYOUT_HORIZONTAL,
231 wxLayoutOrientation
GetOrientation() const;
234 The default handler for the event that is generated by wxLayoutAlgorithm. The
236 of this function calls wxCalculateLayoutEvent::SetRect to shrink the provided
238 how much space this window takes up. For further details,
239 see wxLayoutAlgorithm and wxCalculateLayoutEvent.
241 void OnCalculateLayout(wxCalculateLayoutEvent
& event
);
244 The default handler for the event that is generated by OnCalculateLayout to get
245 size, alignment and orientation information for the window. The implementation
246 of this function uses member variables as set by accessors called by the
248 For further details, see wxLayoutAlgorithm and wxQueryLayoutInfoEvent.
250 void OnQueryLayoutInfo(wxQueryLayoutInfoEvent
& event
);
253 Sets the alignment of the window (which edge of the available parent client
255 is attached to). @a alignment is one of wxLAYOUT_TOP, wxLAYOUT_LEFT,
256 wxLAYOUT_RIGHT, wxLAYOUT_BOTTOM.
258 void SetAlignment(wxLayoutAlignment alignment
);
261 Sets the default dimensions of the window. The dimension other than the
262 orientation will be fixed to this
263 value, and the orientation dimension will be ignored and the window stretched
264 to fit the available space.
266 void SetDefaultSize(const wxSize
& size
);
269 Sets the orientation of the window (the direction the window will stretch in,
270 to fill the available
271 parent client area). @a orientation is one of wxLAYOUT_HORIZONTAL,
274 void SetOrientation(wxLayoutOrientation orientation
);
280 @class wxQueryLayoutInfoEvent
283 This event is sent when wxLayoutAlgorithm wishes to get
284 the size, orientation and alignment of a window. More precisely, the event is
286 by the OnCalculateLayout handler which is itself invoked by wxLayoutAlgorithm.
291 @see wxCalculateLayoutEvent, wxSashLayoutWindow, wxLayoutAlgorithm.
293 class wxQueryLayoutInfoEvent
: public wxEvent
299 wxQueryLayoutInfoEvent(wxWindowID id
= 0);
302 Specifies the alignment of the window (which side of the remaining parent
304 the window sticks to). One of wxLAYOUT_TOP, wxLAYOUT_LEFT, wxLAYOUT_RIGHT,
307 void GetAlignment() const;
310 Returns the flags associated with this event. Not currently used.
312 int GetFlags() const;
315 Returns the orientation that the event handler specified to the event object.
316 May be one of wxLAYOUT_HORIZONTAL,
319 wxLayoutOrientation
GetOrientation() const;
322 Returns the requested length of the window in the direction of the window
323 orientation. This information
326 int GetRequestedLength() const;
329 Returns the size that the event handler specified to the event object as being
330 the requested size of the window.
332 wxSize
GetSize() const;
335 Call this to specify the alignment of the window (which side of the remaining
337 the window sticks to). May be one of wxLAYOUT_TOP, wxLAYOUT_LEFT,
338 wxLAYOUT_RIGHT, wxLAYOUT_BOTTOM.
340 void SetAlignment(wxLayoutAlignment alignment
);
343 Sets the flags associated with this event. Not currently used.
345 void SetFlags(int flags
);
348 Call this to specify the orientation of the window. May be one of
352 void SetOrientation(wxLayoutOrientation orientation
);
355 Sets the requested length of the window in the direction of the window
356 orientation. This information
359 void SetRequestedLength(int length
);
362 Call this to let the calling code know what the size of the window is.
364 void SetSize(const wxSize
& size
);
370 @class wxCalculateLayoutEvent
373 This event is sent by wxLayoutAlgorithm to
374 calculate the amount of the remaining client area that the window should
380 @see wxQueryLayoutInfoEvent, wxSashLayoutWindow, wxLayoutAlgorithm.
382 class wxCalculateLayoutEvent
: public wxEvent
388 wxCalculateLayoutEvent(wxWindowID id
= 0);
391 Returns the flags associated with this event. Not currently used.
393 int GetFlags() const;
396 Before the event handler is entered, returns the remaining parent client area
398 could occupy. When the event handler returns, this should contain the remaining
399 parent client rectangle,
400 after the event handler has subtracted the area that its window occupies.
402 wxRect
GetRect() const;
405 Sets the flags associated with this event. Not currently used.
407 void SetFlags(int flags
);
410 Call this to specify the new remaining parent client area, after the space
412 window has been subtracted.
414 void SetRect(const wxRect
& rect
);