docs/latex/wx/sizer.tex

   1 \section{\class{wxSizer}}\label{wxsizer}
   2
   3 wxSizer is the abstract base class used for laying out subwindows in a window. You
   4 cannot use wxSizer directly; instead, you'll have to use \helpref{wxBoxSizer}{wxboxsizer}
   5 or \helpref{wxStaticBoxSizer}{wxstaticboxsizer}.
   6
   7 The layout algorithm used by sizers in wxWindows closely related to layout
   8 in other GUI toolkits, such as Java's AWT, the GTK toolkit or the Qt toolkit. It is
   9 based upon the idea of the individual subwindows reporting their minimal required
  10 size and their ability to get stretched if the size of the parent window has changed.
  11 This will most often mean, that the programmer does not set the original size of
  12 the dialog in the beginning, rather the top-most sizer will get queried and it will
  13 then query its children. Its children can be normal windows or other sizers, so that
  14 a hierachy of sizer can be constructed. Note that sizer are not derived from wxWindows
  15 and thus do not interfere with tab ordering and require very little resources compared
  16 to a real window on screen.
  17
  18 What makes sizers so well fitted for use in wxWindows, is the fact that every control
  19 reports its own minimal size and the algorithm can handle differences in font sizes
  20 or different window (dialog item) sizes on different platforms without problems. If e.g.
  21 the standard font as well as the overall design of Motif widgets requires more space than
  22 on Windows, the intial dialog size will automatically be bigger on Motif than on Windows.
  23
  24 \pythonnote{If you wish to create a sizer class in wxPython you should
  25 derive the class from \tt{wxPySizer} in order to get Python-aware
  26 capabilities for the various virtual methods.}
  27
  28 \wxheading{Derived from}
  29
  30 \helpref{wxObject}{wxobject}
  31
  32 \latexignore{\rtfignore{\wxheading{Members}}}
  33
  34 \membersection{wxSizer::wxSizer}\label{wxsizerwxsizer}
  35
  36 \func{}{wxSizer}{\void}
  37
  38 The constructor. Note that wxSizer is an abstract base class and may not
  39 be instantiated.
  40
  41 \membersection{wxSizer::\destruct{wxSizer}}\label{wxsizerdtor}
  42
  43 \func{}{\destruct{wxSizer}}{\void}
  44
  45 The destructor.
  46
  47 \membersection{wxSizer::Add}\label{wxsizeradd}
  48
  49 \func{void}{Add}{\param{wxWindow* }{window}, \param{int }{option = 0},\param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
  50
  51 \func{void}{Add}{\param{wxSizer* }{sizer}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
  52
  53 \func{void}{Add}{\param{int }{width}, \param{int }{height}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
  54
  55 Adds the {\it window} to the sizer. As wxSizer itself is an abstract class, the parameters
  56 have no meaning in the wxSizer class itself, but as there currently is only one class
  57 deriving directly from wxSizer and this class does not override these methods, the meaning
  58 of the paramters is described here:
  59
  60 \docparam{window}{The window to be added to the sizer. Its initial size (either set explicitly by the
  61 user or calculated internally when using wxDefaultSize) is interpreted as the minimal and in many
  62 cases also the initial size. This is particularly useful in connection with \helpref{SetSizeHint}{wxsizersetsizehints}.}
  63
  64 \docparam{sizer}{The (child-)sizer to be added to the sizer. This allows placing a child sizer in a
  65 sizer and thus to create hierarchies of sizers (typically a vertical box as the top sizer and several
  66 horizontal boxes on the level beneath).}
  67
  68 \docparam{width and height}{The dimension of a spacer to be added to the sizer. Adding spacers to sizers
  69 gives more flexilibilty in the design of dialogs; imagine for example a vertical box with two buttons at the
  70 bottom of a dialog: you might want to insert a space between the two buttons and make that space stretchable
  71 using the {\it option} flag and the result will be that the left button will be aligned with the left
  72 side of the dialog and the right button with the right side - the space in between will shrink and grow with
  73 the dialog.}
  74
  75 \docparam{option}{Although the meaning of this parameter is undefined in wxSizer, it is used in wxBoxSizer
  76 to indicate if a child of a sizer can change its size in the main orientation of the wxBoxSizer - where
  77 0 stands for not changable and a value of more than zero in interpreted relative to the value of other
  78 children of the same wxBoxSizer. You might, e.g., have a horizontal wxBoxSizer with three children, two
  79 of which are supposed to change their size with the sizer, then the two stretchable windows would get a
  80 value of 1 each to make them grow and shrink equally with the sizer's horizontal dimension.}
  81
  82 \docparam{flag}{This parameter can be used to set a number of flags which can be combined using
  83 the binary OR operator |. Two main behaviours are defined using these flags: One is the border
  84 around a window: the {\it border} parameter determines the border width whereas the flags given here
  85 determine where the border may be (wxTOP, wxBOTTOM, wxLEFT, wxRIGHT or wxALL). The other flags
  86 determine the child window's behaviour if the size of the sizer changes, but - in contrast to
  87 the {\it option} flag - not in the main orientation, but the respectively other orientation. So
  88 if you created a wxBoxSizer with the wxVERTICAL option, these flags will be relevant if the
  89 sizer changes its horizontal size. A child may get resized to completely fill out the new size (using
  90 either wxGROW or wxEXPAND), may get proportionally resized (wxSHAPED), may get centered (wxALIGN\_CENTER
  91 or wxALIGN\_CENTRE) or may get aligned to either side (wxALIGN\_LEFT and wxALIGN\_TOP are set to 0
  92 and thus represent the default, wxALIGN\_RIGHT and wxALIGN\_BOTTOM have their obvious meaning).
  93 With proportional resize, a child may also be centered in the main orientation using
  94 wxALIGN\_CENTER\_VERTICAL (same as wxALIGN\_CENTRE\_VERTICAL) and wxALIGN\_CENTER\_HORIZONTAL
  95 (same as wxALIGN\_CENTRE\_HORIZONTAL) flags.}
  96
  97 \docparam{border}{Determines the border width, if the {\it flag} parameter is set to any border.}
  98
  99 \docparam{userData}{Allows an extra object to be attached to the sizer
 100 item, for use in derived classes when sizing information is more
 101 complex than what {\it option} and {\it flag} will allow for.}
 102
 103 \membersection{wxSizer::Prepend}\label{wxsizerprepend}
 104
 105 \func{void}{Prepend}{\param{wxWindow* }{window}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
 106
 107 \func{void}{Prepend}{\param{wxSizer* }{sizer}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
 108
 109 \func{void}{Prepend}{\param{int }{width}, \param{int }{height}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border= 0}, \param{wxObject* }{userData = NULL}}
 110
 111 Same as \helpref{wxSizer::Add}{wxsizeradd}, but prepends the items to the beginning of the
 112 list of items (windows, subsizers or spaces) owned by this sizer.
 113
 114 \membersection{wxSizer::Remove}\label{wxsizerremove}
 115
 116 \func{bool}{Remove}{\param{wxWindow* }{window}}
 117
 118 \func{bool}{Remove}{\param{wxSizer* }{sizer}}
 119
 120 \func{bool}{Remove}{\param{int }{nth}}
 121
 122 Removes a child from the sizer. {\it window} is the window to be removed, {\it sizer} the
 123 equivalent sizer and {\it nth} is the position of the child in the sizer, typically 0 for
 124 the first item. This method does not cause any layout or resizing to take place and does
 125 not delete the window itself. Call \helpref{wxSizer::Layout}{wxsizerlayout} for updating
 126 the layout "on screen" after removing a child fom the sizer.
 127
 128 Returns TRUE if the child item was found and removed, FALSE otherwise.
 129
 130 \membersection{wxSizer::SetDimension}\label{wxsizersetdimension}
 131
 132 \func{void}{SetDimension}{\param{int }{x}, \param{int }{y}, \param{int }{width}, \param{int }{height}}
 133
 134 Call this to force the sizer to take the given dimension and thus force the items owned
 135 by the sizer to resize themselves according to the rules defined by the paramater in the
 136 \helpref{wxSizer::Add}{wxsizeradd} and \helpref{wxSizer::Prepend}{wxsizerprepend} methods.
 137
 138 \membersection{wxSizer::GetSize}\label{wxsizergetsize}
 139
 140 \func{wxSize}{GetSize}{\void}
 141
 142 Returns the current size of the sizer.
 143
 144 \membersection{wxSizer::GetPosition}\label{wxsizergetposition}
 145
 146 \func{wxPoint}{GetPosition}{\void}
 147
 148 Returns the current position of the sizer.
 149
 150 \membersection{wxSizer::GetMinSize}\label{wxsizergetminsize}
 151
 152 \func{wxSize}{GetMinSize}{\void}
 153
 154 Returns the minimal size of the sizer.
 155
 156 \membersection{wxSizer::RecalcSizes}\label{wxsizerrecalcsizes}
 157
 158 \func{void}{RecalcSizes}{\void}
 159
 160 This method is abstract and has to be overwritten by any derived class.
 161 Here, the sizer will do the actual calculation of its children's positions
 162 and sizes.
 163
 164 \membersection{wxSizer::CalcMin}\label{wxsizercalcmin}
 165
 166 \func{wxSize}{CalcMin}{\void}
 167
 168 This method is abstract and has to be overwritten by any derived class.
 169 Here, the sizer will do the actual calculation of its children minimal sizes.
 170
 171 \membersection{wxSizer::Layout}\label{wxsizerlayout}
 172
 173 \func{void}{Layout}{\void}
 174
 175 Call this to force laying out the children anew, e.g. after having added a child
 176 to or removed a child (window, other sizer or space) from the sizer while keeping
 177 the current dimension.
 178
 179 \membersection{wxSizer::Fit}\label{wxsizerfit}
 180
 181 \func{void}{Fit}{\param{wxWindow* }{window}}
 182
 183 Tell the sizer to resize the {\it window} to match the sizer's minimal size. This
 184 is commonly done in the constructor of the window itself, see sample in the description
 185 of \helpref{wxBoxSizer}{wxboxsizer}.
 186
 187 \membersection{wxSizer::SetSizeHints}\label{wxsizersetsizehints}
 188
 189 \func{void}{SetSizeHints}{\param{wxWindow* }{window}}
 190
 191 Tell the sizer to set the minimal size of the {\it window} to match the sizer's minimal size.
 192 This is commonly done in the constructor of the window itself, see sample in the description
 193 of \helpref{wxBoxSizer}{wxboxsizer} if the window is resizable (as many dialogs under Unix and
 194 frames on probably all platforms).
 195