wxSizer is the abstract base class used for laying out subwindows in a window. You cannot use wxSizer directly; instead, you will have to use one of the sizer classes derived from it. Currently there are wxBoxSizer, wxStaticBoxSizer, wxGridSizer wxFlexGridSizer and wxGridBagSizer.
The layout algorithm used by sizers in wxWidgets is closely related to layout in other GUI toolkits, such as Java's AWT, the GTK toolkit or the Qt toolkit. It is based upon the idea of the individual subwindows reporting their minimal required size and their ability to get stretched if the size of the parent window has changed. This will most often mean that the programmer does not set the original size of a dialog in the beginning, rather the dialog will be assigned a sizer and this sizer will be queried about the recommended size. The sizer in turn will query its children, which can be normal windows, empty space or other sizers, so that a hierarchy of sizers can be constructed. Note that wxSizer does not derive from wxWindow and thus does not interfere with tab ordering and requires very little resources compared to a real window on screen.
What makes sizers so well fitted for use in wxWidgets is the fact that every control reports its own minimal size and the algorithm can handle differences in font sizes or different window (dialog item) sizes on different platforms without problems. If e.g. the standard font as well as the overall design of Motif widgets requires more space than on Windows, the initial dialog size will automatically be bigger on Motif than on Windows.
Sizers may also be used to control the layout of custom drawn items on the window. The Add, Insert, and Prepend functions return a pointer to the newly added wxSizerItem. Just add empty space of the desired size and attributes, and then use the wxSizerItem::GetRect method to determine where the drawing operations should take place.
wxPython での注意点: If you wish to create a sizer class in wxPython you should derive the class from wxPySizer in order to get Python-aware capabilities for the various virtual methods.
The constructor. Note that wxSizer is an abstract base class and may not be instantiated.
Appends a child to the sizer. wxSizer itself is an abstract class, but the parameters are equivalent in the derived classes that you will instantiate to use it so they are described here:
|wxALL||These flags are used to specify which side(s) of the sizer item the border width will apply to.|
|wxEXPAND||The item will be expanded to fill the space assigned to the item.|
|wxSHAPED||The item will be expanded as much as possible while also maintaining its aspect ratio|
|wxFIXED_MINSIZE||Normally wxSizers will use GetAdjustedBestSize to determine what the minimal size of window items should be, and will use that size to calculate the layout. This allows layouts to adjust when an item changes and its best size becomes different. If you would rather have a window item stay the size it started with then use wxFIXED_MINSIZE.|
|wxALIGN_CENTER_HORIZONTAL||The wxALIGN flags allow you to specify the alignment of the item within the space allotted to it by the sizer, adjusted for the border if any.|
Adds non-stretchable space to the sizer. More readable way of calling Add(size, size, 0).
Adds stretchable space to the sizer. More readable way of calling Add(0, 0, prop).
This method is abstract and has to be overwritten by any derived class. Here, the sizer will do the actual calculation of its children minimal sizes.
Detach a child from the sizer without destroying it. window is the window to be detached, sizer is the equivalent sizer and index is the position of the child in the sizer, typically 0 for the first item. This method does not cause any layout or resizing to take place, call wxSizer::Layout to update the layout "on screen" after detaching a child from the sizer.
Returns true if the child item was found and detached, false otherwise.
Tell the sizer to resize the window to match the sizer's minimal size. This is commonly done in the constructor of the window itself, see sample in the description of wxBoxSizer. Returns the new size.
For a top level window this is the total window size, not client size.
Tell the sizer to resize the virtual size of the window to match the sizer's minimal size. This will not alter the on screen size of the window, but may cause the addition/removal/alteration of scrollbars required to view the virtual area in windows which manage it.
Finds item of the sizer which holds given window, sizer or is located in sizer at position index. Use parameter recursive to search in subsizers too.
Returns pointer to item or NULL.
Returns the current size of the sizer.
Returns the current position of the sizer.
Returns the minimal size of the sizer. This is either the combined minimal size of all the children and their borders or the minimal size set by SetMinSize, depending on which is bigger.
Insert a child into the sizer before any existing item at index.
See wxSizer::Add for the meaning of the other parameters.
Inserts non-stretchable space to the sizer. More readable way of calling Insert(size, size, 0).
Inserts stretchable space to the sizer. More readable way of calling Insert(0, 0, prop).
Call this to force layout of the children anew, e.g. after having added a child to or removed a child (window, other sizer or space) from the sizer while keeping the current dimension.
Same as wxSizer::Add, but prepends the items to the beginning of the list of items (windows, subsizers or spaces) owned by this sizer.
Prepends non-stretchable space to the sizer. More readable way of calling Prepend(size, size, 0).
Prepends stretchable space to the sizer. More readable way of calling Prepend(0, 0, prop).
This method is abstract and has to be overwritten by any derived class. Here, the sizer will do the actual calculation of its children's positions and sizes.
Removes a child from the sizer and destroys it. sizer is the wxSizer to be removed, index is the position of the child in the sizer, typically 0 for the first item. This method does not cause any layout or resizing to take place, call wxSizer::Layout to update the layout "on screen" after removing a child from the sizer.
NB: The method taking a wxWindow* parameter is deprecated. For historical reasons it does not destroy the window as would usually be expected from Remove. You should use wxSizer::Detach in new code instead. There is currently no wxSizer method that will both detach and destroy a wxWindow item.
Returns true if the child item was found and removed, false otherwise.
Call this to force the sizer to take the given dimension and thus force the items owned by the sizer to resize themselves according to the rules defined by the parameter in the Add and Prepend methods.
Call this to give the sizer a minimal size. Normally, the sizer will calculate its minimal size based purely on how much space its children need. After calling this method GetMinSize will return either the minimal size as requested by its children or the minimal size set here, depending on which is bigger.
Set an item's minimum size by window, sizer, or position. The item will be found recursively in the sizer's descendants. This function enables an application to set the size of an item after initial creation.
Tell the sizer to set (and Fit) the minimal size of the window to match the sizer's minimal size. This is commonly done in the constructor of the window itself, see sample in the description of wxBoxSizer if the window is resizable (as are many dialogs under Unix and frames on probably all platforms).
Tell the sizer to set the minimal size of the window virtual area to match the sizer's minimal size. For windows with managed scrollbars this will set them appropriately.
Shows or hides the window, sizer, or item at index. To make a sizer item disappear or reappear, use Show() followed by Layout(). Use parameter recursive to show or hide elements found in subsizers.
Returns true if the child item was found, false otherwise.
Note that this only works with wxBoxSizer and wxFlexGridSizer, since they are the only two sizer classes that can size rows/columns independently.