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 vertical 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 centered (wxCENTER or wxCENTRE) or may get aligned to either
  91 side (wxALIGN\_LEFT and wxALIGN\_TOP are set to 0 and thus represent the default, wxALIGN\_RIGHT and
  92 wxALIGN\_BOTTOM have their obvious meaning.}
  93
  94 \docparam{border}{Determines the border width, if the {\it flag} parameter is set to any border.}
  95
  96 \docparam{userData}{Allows an extra object to be attached to the sizer
  97 item, for use in derived classes when sizing information is more
  98 complex than what {\it option} and {\it flag} will allow for.}
  99
 100 \membersection{wxSizer::Prepend}\label{wxsizerprepend}
 101
 102 \func{void}{Prepend}{\param{wxWindow* }{window}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
 103
 104 \func{void}{Prepend}{\param{wxSizer* }{sizer}, \param{int }{option = 0}, \param{int }{flag = 0}, \param{int }{border = 0}, \param{wxObject* }{userData = NULL}}
 105
 106 \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}}
 107
 108 Same as \helpref{wxSizer::Add}{wxsizeradd}, but prepends the items to the beginning of the
 109 list of items (windows, subsizers or spaces) owned by this sizer.
 110
 111 \membersection{wxSizer::Remove}\label{wxsizerremove}
 112
 113 \func{bool}{Remove}{\param{wxWindow* }{window}}
 114
 115 \func{bool}{Remove}{\param{wxSizer* }{sizer}}
 116
 117 \func{bool}{Remove}{\param{int }{nth}}
 118
 119 Removes a child from the sizer. {\it window} is the window to be removed, {\it sizer} the
 120 equivalent sizer and {\it nth} is the position of the child in the sizer, typically 0 for
 121 the first item. This method does not cause any layout or resizing to take place and does
 122 not delete the window itself. Call \helpref{wxSizer::Layout}{wxsizerlayout} for updating
 123 the layout "on screen" after removing a child fom the sizer.
 124
 125 Returns TRUE if the child item was found and removed, FALSE otherwise.
 126
 127 \membersection{wxSizer::SetDimension}\label{wxsizersetdimension}
 128
 129 \func{void}{SetDimension}{\param{int }{x}, \param{int }{y}, \param{int }{width}, \param{int }{height}}
 130
 131 Call this to force the sizer to take the given dimension and thus force the items owned
 132 by the sizer to resize themselves according to the rules defined by the paramater in the
 133 \helpref{wxSizer::Add}{wxsizeradd} and \helpref{wxSizer::Prepend}{wxsizerprepend} methods.
 134
 135 \membersection{wxSizer::GetSize}\label{wxsizergetsize}
 136
 137 \func{wxSize}{GetSize}{\void}
 138
 139 Returns the current size of the sizer.
 140
 141 \membersection{wxSizer::GetPosition}\label{wxsizergetposition}
 142
 143 \func{wxPoint}{GetPosition}{\void}
 144
 145 Returns the current position of the sizer.
 146
 147 \membersection{wxSizer::GetMinSize}\label{wxsizergetminsize}
 148
 149 \func{wxSize}{GetMinSize}{\void}
 150
 151 Returns the minimal size of the sizer.
 152
 153 \membersection{wxSizer::RecalcSizes}\label{wxsizerrecalcsizes}
 154
 155 \func{void}{RecalcSizes}{\void}
 156
 157 This method is abstract and has to be overwritten by any derived class.
 158 Here, the sizer will do the actual calculation of its children's positions
 159 and sizes.
 160
 161 \membersection{wxSizer::CalcMin}\label{wxsizercalcmin}
 162
 163 \func{wxSize}{CalcMin}{\void}
 164
 165 This method is abstract and has to be overwritten by any derived class.
 166 Here, the sizer will do the actual calculation of its children minimal sizes.
 167
 168 \membersection{wxSizer::Layout}\label{wxsizerlayout}
 169
 170 \func{void}{Layout}{\void}
 171
 172 Call this to force laying out the children anew, e.g. after having added a child
 173 to or removed a child (window, other sizer or space) from the sizer while keeping
 174 the current dimension.
 175
 176 \membersection{wxSizer::Fit}\label{wxsizerfit}
 177
 178 \func{void}{Fit}{\param{wxWindow* }{window}}
 179
 180 Tell the sizer to resize the {\it window} to match the sizer's minimal size. This
 181 is commonly done in the constructor of the window itself, see sample in the description
 182 of \helpref{wxBoxSizer}{wxboxsizer}.
 183
 184 \membersection{wxSizer::SetSizeHints}\label{wxsizersetsizehints}
 185
 186 \func{void}{SetSizeHints}{\param{wxWindow* }{window}}
 187
 188 Tell the sizer to set the minimal size of the {\it window} to match the sizer's minimal size.
 189 This is commonly done in the constructor of the window itself, see sample in the description
 190 of \helpref{wxBoxSizer}{wxboxsizer} if the window is resizable (as many dialogs under Unix and
 191 frames on probably all platforms).
 192