X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/36c9828f702fb504b07968703bcd82f04196070a..2e18fe7139558b3cb592a04a4e4668319a966ebf:/docs/doxygen/overviews/sizer.h diff --git a/docs/doxygen/overviews/sizer.h b/docs/doxygen/overviews/sizer.h index b6eeca0f7e..e551e6af79 100644 --- a/docs/doxygen/overviews/sizer.h +++ b/docs/doxygen/overviews/sizer.h @@ -1,342 +1,371 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: sizer +// Name: sizer.h // Purpose: topic overview // Author: wxWidgets team // RCS-ID: $Id$ -// Licence: wxWindows license +// Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// -/*! +/** - @page sizer_overview Sizer overview +@page overview_sizer Sizers Overview - Classes: #wxSizer, #wxGridSizer, - #wxFlexGridSizer, #wxBoxSizer, - #wxStaticBoxSizer, - #CreateButtonSizer - Sizers, as represented by the wxSizer class and its descendants in - the wxWidgets class hierarchy, have become the method of choice to - define the layout of controls in dialogs in wxWidgets because of - their ability to create visually appealing dialogs independent of the - platform, taking into account the differences in size and style of - the individual controls. Unlike the original wxWidgets Dialog Editor, - editors such as wxDesigner, DialogBlocks, XRCed and wxWorkshop create dialogs based exclusively on sizers, - practically forcing the user to create platform independent layouts without compromises. - The next section describes and shows what can be done with sizers. - The following sections briefly describe how to program with individual sizer classes. - For information about the new wxWidgets resource system, which can describe - sizer-based dialogs, see the @ref xrc_overview. - @ref ideabehindsizers_overview - @ref boxsizerprogramming_overview - @ref gridsizerprogramming_overview - @ref flexgridsizerprogramming_overview - @ref staticboxsizerprogramming_overview - #CreateButtonSizer - - - @section ideabehindsizers The idea behind sizers - - The layout algorithm used by sizers in wxWidgets is closely related to layout - systems in other GUI toolkits, such as Java's AWT, the GTK toolkit or the Qt toolkit. It is - based upon the idea of 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 start-up size of - a dialog, the dialog will rather be assigned a sizer and this sizer - will be queried about the recommended size. This 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 few 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. For example, if - the standard font as well as the overall design of Linux/GTK widgets requires more space than - on Windows, the initial dialog size will automatically be bigger on Linux/GTK than on Windows. - There are currently five different kinds of sizers available in wxWidgets. Each represents - either a certain way to lay out dialog items in a dialog or it fulfills a special task - such as wrapping a static box around a dialog item (or another sizer). These sizers will - be discussed one by one in the text below. For more detailed information on how to use sizers - programmatically, please refer to the section @ref boxsizerprogramming_overview. +Classes: wxSizer, wxBoxSizer, wxStaticBoxSizer, wxGridSizer, wxFlexGridSizer, + wxGridBagSizer - @section sizerscommonfeatures Common features +Sizers, as represented by the wxSizer class and its descendants in the +wxWidgets class hierarchy, have become the method of choice to define the +layout of controls in dialogs in wxWidgets because of their ability to create +visually appealing dialogs independent of the platform, taking into account +the differences in size and style of the individual controls. Unlike the +original wxWidgets Dialog Editor, editors such as wxDesigner, DialogBlocks, +XRCed and wxWorkshop create dialogs based exclusively on sizers, practically +forcing the user to create platform independent layouts without compromises. + +The next section describes and shows what can be done with sizers. The +following sections briefly describe how to program with individual sizer +classes. + +For information about the wxWidgets resource system, which can describe +sizer-based dialogs, see the @ref overview_xrc. + +@li @ref overview_sizer_idea +@li @ref overview_sizer_features +@li @ref overview_sizer_hiding +@li @ref overview_sizer_box +@li @ref overview_sizer_types +@li @ref overview_sizer_button - All sizers are containers, that is, they are used to lay out one dialog item (or several - dialog items), which they contain. Such items are sometimes referred to as the children - of the sizer. Independent of how the individual sizers lay out their children, all children - have certain features in common: - @b A minimal size: This minimal size is usually identical to - the initial size of the controls and may either be set explicitly in the wxSize field - of the control constructor or may be calculated by wxWidgets, typically by setting - the height and/or the width of the item to -1. Note that only some controls can - calculate their size (such as a checkbox) whereas others (such as a listbox) - don't have any natural width or height and thus require an explicit size. Some controls - can calculate their height, but not their width (e.g. a single line text control): +
+@section overview_sizer_idea The Idea Behind Sizers +The layout algorithm used by sizers in wxWidgets is closely related to layout +systems in other GUI toolkits, such as Java's AWT, the GTK toolkit or the Qt +toolkit. It is based upon the idea of 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 start-up size of a dialog, the dialog will rather be assigned a +sizer and this sizer will be queried about the recommended size. This 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 few 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. For example, if the standard font as well as the overall +design of Linux/GTK widgets requires more space than on Windows, the initial +dialog size will automatically be bigger on Linux/GTK than on Windows. +There are currently five different kinds of sizers available in wxWidgets. Each +represents either a certain way to lay out dialog items in a dialog or it +fulfills a special task such as wrapping a static box around a dialog item (or +another sizer). These sizers will be discussed one by one in the text below. +For more detailed information on how to use sizers programmatically, please +refer to the section @ref overview_sizer_box. - @b A border: The border is just empty space and is used to separate dialog items - in a dialog. This border can either be all around, or at any combination of sides - such as only above and below the control. The thickness of this border must be set - explicitly, typically 5 points. The following samples show dialogs with only one - dialog item (a button) and a border of 0, 5, and 10 pixels around the button: +@section overview_sizer_features Common Features +All sizers are containers, that is, they are used to lay out one dialog item +(or several dialog items), which they contain. Such items are sometimes +referred to as the children of the sizer. Independent of how the individual +sizers lay out their children, all children have certain features in common: +A minimal size: This minimal size is usually identical to the initial +size of the controls and may either be set explicitly in the wxSize field of +the control constructor or may be calculated by wxWidgets, typically by setting +the height and/or the width of the item to -1. Note that only some controls can +calculate their size (such as a checkbox) whereas others (such as a listbox) +don't have any natural width or height and thus require an explicit size. Some +controls can calculate their height, but not their width (e.g. a single line +text control): +@image html overview_sizer_03.png +@image html overview_sizer_04.png +@image html overview_sizer_05.png +A border: The border is just empty space and is used to separate dialog +items in a dialog. This border can either be all around, or at any combination +of sides such as only above and below the control. The thickness of this border +must be set explicitly, typically 5 points. The following samples show dialogs +with only one dialog item (a button) and a border of 0, 5, and 10 pixels around +the button: - @b An alignment: Often, a dialog item is given more space than its minimal size - plus its border. Depending on what flags are used for the respective dialog - item, the dialog item can be made to fill out the available space entirely, i.e. - it will grow to a size larger than the minimal size, or it will be moved to either - the centre of the available space or to either side of the space. The following - sample shows a listbox and three buttons in a horizontal box sizer; one button - is centred, one is aligned at the top, one is aligned at the bottom: - - - - @b A stretch factor: If a sizer contains more than one child and it is offered - more space than its children and their borders need, the question arises how to - distribute the surplus space among the children. For this purpose, a stretch - factor may be assigned to each child, where the default value of 0 indicates that the child - will not get more space than its requested minimum size. A value of more than zero - is interpreted in relation to the sum of all stretch factors in the children - of the respective sizer, i.e. if two children get a stretch factor of 1, they will - get half the extra space each @e independent of whether one control has a minimal - sizer inferior to the other or not. The following sample shows a dialog with - three buttons, the first one has a stretch factor of 1 and thus gets stretched, - whereas the other two buttons have a stretch factor of zero and keep their - initial width: - - - - Within wxDesigner, this stretch factor gets set from the @e Option menu. - - @section sizershiding Hiding controls using sizers - - You can hide controls contained in sizers the same way you would hide any control, - using the wxWindow::Show method. - However, wxSizer also offers a separate method which can tell the sizer not to - consider that control in its size calculations. To hide a window using the sizer, - call wxSizer::Show. You must then call Layout on the sizer - to force an update. - This is useful when hiding parts of the interface, since you can avoid removing - the controls from the sizer and having to add them back later. - Note: This is supported only by wxBoxSizer and wxFlexGridSizer. - @b wxBoxSizer - #wxBoxSizer can lay out its children either vertically - or horizontally, depending on what flag is being used in its constructor. - When using a vertical sizer, each child can be centered, aligned to the - right or aligned to the left. Correspondingly, when using a horizontal - sizer, each child can be centered, aligned at the bottom or aligned at - the top. The stretch factor described in the last paragraph is used - for the main orientation, i.e. when using a horizontal box sizer, the - stretch factor determines how much the child can be stretched horizontally. - The following sample shows the same dialog as in the last sample, - only the box sizer is a vertical box sizer now: - - - - @b wxStaticBoxSizer - #wxStaticBoxSixer is the same as a wxBoxSizer, but surrounded by a - static box. Here is a sample: - - - - @b wxGridSizer - #wxGridSizer is a two-dimensional sizer. All children are given the - same size, which is the minimal size required by the biggest child, in - this case the text control in the left bottom border. Either the number - of columns or the number or rows is fixed and the grid sizer will grow - in the respectively other orientation if new children are added: - - - - For programming information, see #wxGridSizer. - @b wxFlexGridSizer - Another two-dimensional sizer derived from - wxGridSizer. The width of each column and the height of each row - are calculated individually according to the minimal requirements - from the respectively biggest child. Additionally, columns and - rows can be declared to be stretchable if the sizer is assigned - a size different from the one it requested. The following sample shows - the same dialog as the one above, but using a flex grid sizer: - - - - - @section boxsizerprogramming Programming with wxBoxSizer - - The basic idea behind a #wxBoxSizer is that windows will most often be laid out in rather - simple basic geometry, typically in a row or a column or several hierarchies of either. - As an example, we will construct a dialog that will contain a text field at the top and - two buttons at the bottom. This can be seen as a top-hierarchy column with the text at - the top and buttons at the bottom and a low-hierarchy row with an OK button to the left - and a Cancel button to the right. In many cases (particularly dialogs under Unix and - normal frames) the main window will be resizable by the user and this change of size - will have to get propagated to its children. In our case, we want the text area to grow - with the dialog, whereas the button shall have a fixed size. In addition, there will be - a thin border around all controls to make the dialog look nice and - to make matter worse - - the buttons shall be centred as the width of the dialog changes. - It is the unique feature of a box sizer, that it can grow in both directions (height and - width) but can distribute its growth in the main direction (horizontal for a row) @e unevenly - among its children. In our example case, the vertical sizer is supposed to propagate all its - height changes to only the text area, not to the button area. This is determined by the @e proportion parameter - when adding a window (or another sizer) to a sizer. It is interpreted - as a weight factor, i.e. it can be zero, indicating that the window may not be resized - at all, or above zero. If several windows have a value above zero, the value is interpreted - relative to the sum of all weight factors of the sizer, so when adding two windows with - a value of 1, they will both get resized equally much and each half as much as the sizer - owning them. Then what do we do when a column sizer changes its width? This behaviour is - controlled by @e flags (the second parameter of the Add() function): Zero or no flag - indicates that the window will preserve it is original size, wxGROW flag (same as wxEXPAND) - forces the window to grow with the sizer, and wxSHAPED flag tells the window to change it is - size proportionally, preserving original aspect ratio. When wxGROW flag is not used, - the item can be aligned within available space. wxALIGN_LEFT, wxALIGN_TOP, wxALIGN_RIGHT, - wxALIGN_BOTTOM, wxALIGN_CENTER_HORIZONTAL and wxALIGN_CENTER_VERTICAL do what they say. - wxALIGN_CENTRE (same as wxALIGN_CENTER) is defined as (wxALIGN_CENTER_HORIZONTAL | - wxALIGN_CENTER_VERTICAL). Default alignment is wxALIGN_LEFT | wxALIGN_TOP. - As mentioned above, any window belonging to a sizer may have a border, and it can be specified - which of the four sides may have this border, using the wxTOP, wxLEFT, wxRIGHT and wxBOTTOM - constants or wxALL for all directions (and you may also use wxNORTH, wxWEST etc instead). These - flags can be used in combination with the alignment flags above as the second parameter of the - Add() method using the binary or operator |. The sizer of the border also must be made known, - and it is the third parameter in the Add() method. This means, that the entire behaviour of - a sizer and its children can be controlled by the three parameters of the Add() method. - - @code - // we want to get a dialog that is stretchable because it - // has a text ctrl at the top and two buttons at the bottom - - MyDialog::MyDialog(wxFrame *parent, wxWindowID id, const wxString ) - : wxDialog(parent, id, title, wxDefaultPosition, wxDefaultSize, - wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER) - { - wxBoxSizer *topsizer = new wxBoxSizer( wxVERTICAL ); - - // create text ctrl with minimal size 100x60 - topsizer-Add( - new wxTextCtrl( this, -1, "My text.", wxDefaultPosition, wxSize(100,60), wxTE_MULTILINE), - 1, // make vertically stretchable - wxEXPAND | // make horizontally stretchable - wxALL, // and make border all around - 10 ); // set border width to 10 - - - wxBoxSizer *button_sizer = new wxBoxSizer( wxHORIZONTAL ); - button_sizer-Add( - new wxButton( this, wxID_OK, "OK" ), - 0, // make horizontally unstretchable - wxALL, // make border all around (implicit top alignment) - 10 ); // set border width to 10 - button_sizer-Add( - new wxButton( this, wxID_CANCEL, "Cancel" ), - 0, // make horizontally unstretchable - wxALL, // make border all around (implicit top alignment) - 10 ); // set border width to 10 - - topsizer-Add( - button_sizer, - 0, // make vertically unstretchable - wxALIGN_CENTER ); // no border and centre horizontally - - SetSizerAndFit(topsizer); // use the sizer for layout and size window - // accordingly and prevent it from being resized - // to smaller size - } - @endcode - - Note that the new way of specifying flags to wxSizer is via #wxSizerFlags. This class greatly eases the burden of passing flags to a wxSizer. - Here's how you'd do the previous example with wxSizerFlags: - - @code - // we want to get a dialog that is stretchable because it - // has a text ctrl at the top and two buttons at the bottom - - MyDialog::MyDialog(wxFrame *parent, wxWindowID id, const wxString ) - : wxDialog(parent, id, title, wxDefaultPosition, wxDefaultSize, - wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER) - { - wxBoxSizer *topsizer = new wxBoxSizer( wxVERTICAL ); - - // create text ctrl with minimal size 100x60 that is horizontally and - // vertically stretchable with a border width of 10 - topsizer-Add( - new wxTextCtrl( this, -1, "My text.", wxDefaultPosition, wxSize(100,60), wxTE_MULTILINE), - wxSizerFlags(1).Align().Expand().Border(wxALL, 10)); - - wxBoxSizer *button_sizer = new wxBoxSizer( wxHORIZONTAL ); - - //create two buttons that are horizontally unstretchable, - // with an all-around border with a width of 10 and implicit top alignment - button_sizer-Add( - new wxButton( this, wxID_OK, "OK" ), - wxSizerFlags(0).Align().Border(wxALL, 10)); - - button_sizer-Add( - new wxButton( this, wxID_CANCEL, "Cancel" ), - wxSizerFlags(0).Align().Border(wxALL, 10)); - - //create a sizer with no border and centered horizontally - topsizer-Add( - button_sizer, - wxSizerFlags(0).Center() ); - - SetSizerAndFit(topsizer); // use the sizer for layout and set size and hints - } - @endcode - - - - @section gridsizerprogramming Programming with wxGridSizer - - #wxGridSizer is a sizer which lays out its children in a two-dimensional - table with all table fields having the same size, - i.e. the width of each field is the width of the widest child, - the height of each field is the height of the tallest child. - - @section flexgridsizerprogramming Programming with wxFlexGridSizer - - #wxFlexGridSizer is a sizer which lays out its children in a two-dimensional - table with all table fields in one row having the same - height and all fields in one column having the same width, but all - rows or all columns are not necessarily the same height or width as in - the #wxGridSizer. - - @section staticboxsizerprogramming Programming with wxStaticBoxSizer - - #wxStaticBoxSizer is a sizer derived from wxBoxSizer but adds a static - box around the sizer. Note that this static box has to be created - separately. - - @section createbuttonsizer CreateButtonSizer - - As a convenience, CreateButtonSizer ( long flags ) can be used to create a standard button sizer - in which standard buttons are displayed. The following flags can be passed to this function: - +@image html overview_sizer_00.png - @code - wxYES_NO // Add Yes/No subpanel - wxYES // return wxID_YES - wxNO // return wxID_NO - wxNO_DEFAULT // make the wxNO button the default, otherwise wxYES or wxOK button will be default +@image html overview_sizer_01.png - wxOK // return wxID_OK - wxCANCEL // return wxID_CANCEL - wxHELP // return wxID_HELP +@image html overview_sizer_02.png - wxFORWARD // return wxID_FORWARD - wxBACKWARD // return wxID_BACKWARD - wxSETUP // return wxID_SETUP - wxMORE // return wxID_MORE - @endcode +An alignment: Often, a dialog item is given more space than its minimal +size plus its border. Depending on what flags are used for the respective +dialog item, the dialog item can be made to fill out the available space +entirely, i.e. it will grow to a size larger than the minimal size, or it will +be moved to either the centre of the available space or to either side of the +space. The following sample shows a listbox and three buttons in a horizontal +box sizer; one button is centred, one is aligned at the top, one is aligned at +the bottom: - */ +@image html overview_sizer_06.png + +A stretch factor: If a sizer contains more than one child and it is +offered more space than its children and their borders need, the question +arises how to distribute the surplus space among the children. For this +purpose, a stretch factor may be assigned to each child, where the default +value of 0 indicates that the child will not get more space than its requested +minimum size. A value of more than zero is interpreted in relation to the sum +of all stretch factors in the children of the respective sizer, i.e. if two +children get a stretch factor of 1, they will get half the extra space each +independent of whether one control has a minimal sizer inferior to the +other or not. The following sample shows a dialog with three buttons, the +first one has a stretch factor of 1 and thus gets stretched, whereas the other +two buttons have a stretch factor of zero and keep their initial width: + +@image html overview_sizer_07.png + +Within wxDesigner, this stretch factor gets set from the @e Option menu. + + +@section overview_sizer_hiding Hiding Controls Using Sizers + +You can hide controls contained in sizers the same way you would hide any +control, using the wxWindow::Show method. However, wxSizer also offers a +separate method which can tell the sizer not to consider that control in its +size calculations. To hide a window using the sizer, call wxSizer::Show. You +must then call Layout on the sizer to force an update. + +This is useful when hiding parts of the interface, since you can avoid removing +the controls from the sizer and having to add them back later. + +@note This is supported only by wxBoxSizer and wxFlexGridSizer. + +@subsection overview_sizer_hiding_box wxBoxSizer + +wxBoxSizer can lay out its children either vertically or horizontally, +depending on what flag is being used in its constructor. When using a vertical +sizer, each child can be centered, aligned to the right or aligned to the left. +Correspondingly, when using a horizontal sizer, each child can be centered, +aligned at the bottom or aligned at the top. The stretch factor described in +the last paragraph is used for the main orientation, i.e. when using a +horizontal box sizer, the stretch factor determines how much the child can be +stretched horizontally. The following sample shows the same dialog as in the +last sample, only the box sizer is a vertical box sizer now: + +@image html overview_sizer_08.png + +@subsection overview_sizer_hiding_static wxStaticBoxSizer + +wxStaticBoxSixer is the same as a wxBoxSizer, but surrounded by a static box. +Here is a sample: + +@image html overview_sizer_09.png + +@subsection overview_sizer_hiding_grid wxGridSizer + +wxGridSizer is a two-dimensional sizer. All children are given the same size, +which is the minimal size required by the biggest child, in this case the text +control in the left bottom border. Either the number of columns or the number +or rows is fixed and the grid sizer will grow in the respectively other +orientation if new children are added: + +@image html overview_sizer_10.png + +For programming information, see wxGridSizer. + +@subsection overview_sizer_hiding_flexgrid wxFlexGridSizer + +Another two-dimensional sizer derived from wxGridSizer. The width of each +column and the height of each row are calculated individually according to the +minimal requirements from the respectively biggest child. Additionally, columns +and rows can be declared to be stretchable if the sizer is assigned a size +different from the one it requested. The following sample shows the same dialog +as the one above, but using a flex grid sizer: + +@image html overview_sizer_11.png + + +@section overview_sizer_box Programming with wxBoxSizer + +The basic idea behind a wxBoxSizer is that windows will most often be laid out +in rather simple basic geometry, typically in a row or a column or several +hierarchies of either. + +As an example, we will construct a dialog that will contain a text field at the +top and two buttons at the bottom. This can be seen as a top-hierarchy column +with the text at the top and buttons at the bottom and a low-hierarchy row with +an OK button to the left and a Cancel button to the right. In many cases +(particularly dialogs under Unix and normal frames) the main window will be +resizable by the user and this change of size will have to get propagated to +its children. In our case, we want the text area to grow with the dialog, +whereas the button shall have a fixed size. In addition, there will be a thin +border around all controls to make the dialog look nice and - to make matter +worse - the buttons shall be centred as the width of the dialog changes. + +It is the unique feature of a box sizer, that it can grow in both directions +(height and width) but can distribute its growth in the main direction +(horizontal for a row) @e unevenly among its children. In our example case, the +vertical sizer is supposed to propagate all its height changes to only the text +area, not to the button area. This is determined by the @e proportion parameter +when adding a window (or another sizer) to a sizer. It is interpreted as a +weight factor, i.e. it can be zero, indicating that the window may not be +resized at all, or above zero. If several windows have a value above zero, the +value is interpreted relative to the sum of all weight factors of the sizer, so +when adding two windows with a value of 1, they will both get resized equally +much and each half as much as the sizer owning them. Then what do we do when a +column sizer changes its width? This behaviour is controlled by @e flags (the +second parameter of the Add() function): Zero or no flag indicates that the +window will preserve it is original size, wxGROW flag (same as wxEXPAND) forces +the window to grow with the sizer, and wxSHAPED flag tells the window to change +it is size proportionally, preserving original aspect ratio. When wxGROW flag +is not used, the item can be aligned within available space. wxALIGN_LEFT, +wxALIGN_TOP, wxALIGN_RIGHT, wxALIGN_BOTTOM, wxALIGN_CENTER_HORIZONTAL and +wxALIGN_CENTER_VERTICAL do what they say. wxALIGN_CENTRE (same as +wxALIGN_CENTER) is defined as (wxALIGN_CENTER_HORIZONTAL | +wxALIGN_CENTER_VERTICAL). Default alignment is wxALIGN_LEFT | wxALIGN_TOP. + +As mentioned above, any window belonging to a sizer may have a border, and it +can be specified which of the four sides may have this border, using the wxTOP, +wxLEFT, wxRIGHT and wxBOTTOM constants or wxALL for all directions (and you may +also use wxNORTH, wxWEST etc instead). These flags can be used in combination +with the alignment flags above as the second parameter of the Add() method +using the binary or operator |. The sizer of the border also must be made +known, and it is the third parameter in the Add() method. This means, that the +entire behaviour of a sizer and its children can be controlled by the three +parameters of the Add() method. + +@code +// We want to get a dialog that is stretchable because it +// has a text ctrl at the top and two buttons at the bottom. + +MyDialog::MyDialog(wxFrame *parent, wxWindowID id, const wxString &title ) +: wxDialog(parent, id, title, wxDefaultPosition, wxDefaultSize, + wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER) +{ + wxBoxSizer *topsizer = new wxBoxSizer( wxVERTICAL ); + + // create text ctrl with minimal size 100x60 + topsizer->Add( + new wxTextCtrl( this, -1, "My text.", wxDefaultPosition, wxSize(100,60), wxTE_MULTILINE), + 1, // make vertically stretchable + wxEXPAND | // make horizontally stretchable + wxALL, // and make border all around + 10 ); // set border width to 10 + + wxBoxSizer *button_sizer = new wxBoxSizer( wxHORIZONTAL ); + button_sizer->Add( + new wxButton( this, wxID_OK, "OK" ), + 0, // make horizontally unstretchable + wxALL, // make border all around (implicit top alignment) + 10 ); // set border width to 10 + button_sizer->Add( + new wxButton( this, wxID_CANCEL, "Cancel" ), + 0, // make horizontally unstretchable + wxALL, // make border all around (implicit top alignment) + 10 ); // set border width to 10 + + topsizer->Add( + button_sizer, + 0, // make vertically unstretchable + wxALIGN_CENTER ); // no border and centre horizontally + + SetSizerAndFit(topsizer); // use the sizer for layout and size window + // accordingly and prevent it from being resized + // to smaller size +} +@endcode + +Note that the new way of specifying flags to wxSizer is via wxSizerFlags. This +class greatly eases the burden of passing flags to a wxSizer. + +Here's how you'd do the previous example with wxSizerFlags: + +@code +// We want to get a dialog that is stretchable because it +// has a text ctrl at the top and two buttons at the bottom. + +MyDialog::MyDialog(wxFrame *parent, wxWindowID id, const wxString &title ) +: wxDialog(parent, id, title, wxDefaultPosition, wxDefaultSize, + wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER) +{ + wxBoxSizer *topsizer = new wxBoxSizer( wxVERTICAL ); + + // create text ctrl with minimal size 100x60 that is horizontally and + // vertically stretchable with a border width of 10 + topsizer->Add( + new wxTextCtrl( this, -1, "My text.", wxDefaultPosition, wxSize(100,60), wxTE_MULTILINE), + wxSizerFlags(1).Align().Expand().Border(wxALL, 10)); + + wxBoxSizer *button_sizer = new wxBoxSizer( wxHORIZONTAL ); + + //create two buttons that are horizontally unstretchable, + // with an all-around border with a width of 10 and implicit top alignment + button_sizer->Add( + new wxButton( this, wxID_OK, "OK" ), + wxSizerFlags(0).Align().Border(wxALL, 10)); + + button_sizer->Add( + new wxButton( this, wxID_CANCEL, "Cancel" ), + wxSizerFlags(0).Align().Border(wxALL, 10)); + + //create a sizer with no border and centered horizontally + topsizer->Add( + button_sizer, + wxSizerFlags(0).Center() ); + + SetSizerAndFit(topsizer); // use the sizer for layout and set size and hints +} +@endcode + + + +@section overview_sizer_types Other Types of Sizers + +wxGridSizer is a sizer which lays out its children in a two-dimensional table +with all table fields having the same size, i.e. the width of each field is the +width of the widest child, the height of each field is the height of the +tallest child. + +wxFlexGridSizer is a sizer which lays out its children in a two-dimensional +table with all table fields in one row having the same height and all fields in +one column having the same width, but all rows or all columns are not +necessarily the same height or width as in the wxGridSizer. + +wxStaticBoxSizer is a sizer derived from wxBoxSizer but adds a static box +around the sizer. Note that this static box has to be created separately. + +wxGridBagSizer is a rather special kind of sizer which, unlike the other +classes, allows to directly put the elements at the given position in the +sizer. Please see its documentation for more details. + +@section overview_sizer_button CreateButtonSizer + +As a convenience, wxDialog::CreateButtonSizer(long flags) can be used to create a +standard button sizer in which standard buttons are displayed. The following +flags can be passed to this function: + +@code +wxYES_NO // Add Yes/No subpanel +wxYES // return wxID_YES +wxNO // return wxID_NO +wxNO_DEFAULT // make the wxNO button the default, + // otherwise wxYES or wxOK button will be default + +wxOK // return wxID_OK +wxCANCEL // return wxID_CANCEL +wxHELP // return wxID_HELP + +wxFORWARD // return wxID_FORWARD +wxBACKWARD // return wxID_BACKWARD +wxSETUP // return wxID_SETUP +wxMORE // return wxID_MORE +@endcode +*/