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wxSizer

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 wxBoxSizer, wxStaticBoxSizer or wxNotebookSizer.

The layout algorithm used by sizers in wxWindows 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 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 do 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 wxWindows 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.

wxPython note: 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.

Derived from

wxObject

Members

wxSizer::wxSizer
wxSizer::~wxSizer
wxSizer::Add
wxSizer::CalcMin
wxSizer::Fit
wxSizer::GetSize
wxSizer::GetPosition
wxSizer::GetMinSize
wxSizer::Layout
wxSizer::Prepend
wxSizer::RecalcSizes
wxSizer::Remove
wxSizer::SetDimension
wxSizer::SetMinSize
wxSizer::SetItemMinSize
wxSizer::SetSizeHints


wxSizer::wxSizer

wxSizer()

The constructor. Note that wxSizer is an abstract base class and may not be instantiated.


wxSizer::~wxSizer

~wxSizer()

The destructor.


wxSizer::Add

void Add(wxWindow* window, int option = 0,int flag = 0, int border = 0, wxObject* userData = NULL)

void Add(wxSizer* sizer, int option = 0, int flag = 0, int border = 0, wxObject* userData = NULL)

void Add(int width, int height, int option = 0, int flag = 0, int border = 0, wxObject* userData = NULL)

Adds the window to the sizer. As wxSizer itself is an abstract class, the parameters have no meaning in the wxSizer class itself, but as there currently is only one class deriving directly from wxSizer and this class does not override these methods, the meaning of the parameters is described here:

window

sizer

width and height

option

flag

border

userData


wxSizer::CalcMin

wxSize CalcMin()

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.


wxSizer::Fit

void Fit(wxWindow* window)

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.


wxSizer::GetSize

wxSize GetSize()

Returns the current size of the sizer.


wxSizer::GetPosition

wxPoint GetPosition()

Returns the current position of the sizer.


wxSizer::GetMinSize

wxSize GetMinSize()

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.


wxSizer::Layout

void Layout()

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.


wxSizer::Prepend

void Prepend(wxWindow* window, int option = 0, int flag = 0, int border = 0, wxObject* userData = NULL)

void Prepend(wxSizer* sizer, int option = 0, int flag = 0, int border = 0, wxObject* userData = NULL)

void Prepend(int width, int height, int option = 0, int flag = 0, int border= 0, wxObject* userData = NULL)

Same as wxSizer::Add, but prepends the items to the beginning of the list of items (windows, subsizers or spaces) owned by this sizer.


wxSizer::RecalcSizes

void RecalcSizes()

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.


wxSizer::Remove

bool Remove(wxWindow* window)

bool Remove(wxSizer* sizer)

bool Remove(int nth)

Removes a child from the sizer. window is the window to be removed, sizer is the equivalent sizer and nth 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 and does not delete the window itself. Call wxSizer::Layout to update the layout "on screen" after removing a child fom the sizer.

Returns TRUE if the child item was found and removed, FALSE otherwise.


wxSizer::SetDimension

void SetDimension(int x, int y, int width, int height)

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 paramater in the Add and Prepend methods.


wxSizer::SetMinSize

void SetMinSize(int width, int height)

void SetMinSize(wxSize size)

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.


wxSizer::SetItemMinSize

void SetItemMinSize(wxWindow* window, int width, int height)

void SetItemMinSize(wxSizer* sizer, int width, int height)

void SetItemMinSize(int pos, int width, int height)

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.


wxSizer::SetSizeHints

void SetSizeHints(wxWindow* window)

Tell the sizer to set 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).