wxLayoutAlgorithm - Functions for wxLayoutAlgorithm class
Please see following description for synopsis
wxLayoutAlgorithm(3) Erlang Module Definition wxLayoutAlgorithm(3)
NAME
wxLayoutAlgorithm - Functions for wxLayoutAlgorithm class
DESCRIPTION
wxLayoutAlgorithm implements layout of subwindows in MDI or SDI frames.
It sends a wxCalculateLayoutEvent (not implemented in wx) event to
children of the frame, asking them for information about their size.
For MDI parent frames, the algorithm allocates the remaining space to
the MDI client window (which contains the MDI child frames).
For SDI (normal) frames, a 'main' window is specified as taking up the
remaining space.
Because the event system is used, this technique can be applied to any
windows, which are not necessarily 'aware' of the layout classes (no
virtual functions in wxWindow refer to wxLayoutAlgorithm or its
events). However, you may wish to use wxSashLayoutWindow for your sub-
windows since this class provides handlers for the required events, and
accessors to specify the desired size of the window. The sash behaviour
in the base class can be used, optionally, to make the windows user-
resizable.
wxLayoutAlgorithm is typically used in IDE (integrated development
environment) applications, where there are several resizable windows in
addition to the MDI client window, or other primary editing window.
Resizable windows might include toolbars, a project window, and a win-
dow for displaying error and warning messages.
When a window receives an OnCalculateLayout event, it should call
SetRect in the given event object, to be the old supplied rectangle
minus whatever space the window takes up. It should also set its own
size accordingly. wxSashLayoutWindow::OnCalculateLayout (not imple-
mented in wx) generates an OnQueryLayoutInfo event which it sends to
itself to determine the orientation, alignment and size of the window,
which it gets from internal member variables set by the application.
The algorithm works by starting off with a rectangle equal to the whole
frame client area. It iterates through the frame children, generating
wxLayoutAlgorithm::OnCalculateLayout events which subtract the window
size and return the remaining rectangle for the next window to process.
It is assumed (by wxSashLayoutWindow::OnCalculateLayout (not imple-
mented in wx)) that a window stretches the full dimension of the frame
client, according to the orientation it specifies. For example, a hori-
zontal window will stretch the full width of the remaining portion of
the frame client area. In the other orientation, the window will be
fixed to whatever size was specified by wxLayoutAlgorithm::OnQueryLay-
outInfo. An alignment setting will make the window 'stick' to the left,
top, right or bottom of the remaining client area. This scheme implies
that order of window creation is important. Say you wish to have an
extra toolbar at the top of the frame, a project window to the left of
the MDI client window, and an output window above the status bar. You
should therefore create the windows in this order: toolbar, output win-
dow, project window. This ensures that the toolbar and output window
take up space at the top and bottom, and then the remaining height in-
between is used for the project window.
wxLayoutAlgorithm is quite independent of the way in which wxLayoutAl-
gorithm::OnCalculateLayout chooses to interpret a window's size and
alignment. Therefore you could implement a different window class with
a new wxLayoutAlgorithm::OnCalculateLayout event handler, that has a
more sophisticated way of laying out the windows. It might allow speci-
fication of whether stretching occurs in the specified orientation, for
example, rather than always assuming stretching. (This could, and prob-
ably should, be added to the existing implementation).
Note: wxLayoutAlgorithm has nothing to do with wxLayoutConstraints (not
implemented in wx). It is an alternative way of specifying layouts for
which the normal constraint system is unsuitable.
See: wxSashEvent, wxSashLayoutWindow, Overview events
wxWidgets docs: wxLayoutAlgorithm
DATA TYPES
wxLayoutAlgorithm() = wx:wx_object()
EXPORTS
new() -> wxLayoutAlgorithm()
Default constructor.
destroy(This :: wxLayoutAlgorithm()) -> ok
Destructor.
layoutFrame(This, Frame) -> boolean()
Types:
This = wxLayoutAlgorithm()
Frame = wxFrame:wxFrame()
layoutFrame(This, Frame, Options :: [Option]) -> boolean()
Types:
This = wxLayoutAlgorithm()
Frame = wxFrame:wxFrame()
Option = {mainWindow, wxWindow:wxWindow()}
Lays out the children of a normal frame.
mainWindow is set to occupy the remaining space. This function
simply calls layoutWindow/3.
layoutMDIFrame(This, Frame) -> boolean()
Types:
This = wxLayoutAlgorithm()
Frame = wxMDIParentFrame:wxMDIParentFrame()
layoutMDIFrame(This, Frame, Options :: [Option]) -> boolean()
Types:
This = wxLayoutAlgorithm()
Frame = wxMDIParentFrame:wxMDIParentFrame()
Option =
{rect,
{X :: integer(),
Y :: integer(),
W :: integer(),
H :: integer()}}
Lays out the children of an MDI parent frame.
If rect is non-NULL, the given rectangle will be used as a
starting point instead of the frame's client area. The MDI
client window is set to occupy the remaining space.
layoutWindow(This, Parent) -> boolean()
Types:
This = wxLayoutAlgorithm()
Parent = wxWindow:wxWindow()
layoutWindow(This, Parent, Options :: [Option]) -> boolean()
Types:
This = wxLayoutAlgorithm()
Parent = wxWindow:wxWindow()
Option = {mainWindow, wxWindow:wxWindow()}
Lays out the children of a normal frame or other window.
mainWindow is set to occupy the remaining space. If this is not
specified, then the last window that responds to a calculate
layout event in query mode will get the remaining space (that
is, a non-query OnCalculateLayout event will not be sent to this
window and the window will be set to the remaining size).
wxWidgets team. wx 2.1.1 wxLayoutAlgorithm(3)