wxWidgets/interface/wx/statbox.h
Vadim Zeitlin a67f4b8254 Don't pretend static box with enabled label is disabled
Trying to be smart by setting m_isEnabled to false in
wxStaticBox::Enable() without actually disabling the box itself (because
it can't be done if its label window is to remain enabled) didn't really
work. For example, it was impossible to TAB to a checkbox label of the
box when it was disabled, because keyboard navigation (correctly)
doesn't recurse into disabled windows and there could be similar
problems with any other code iterating over windows and skipping over
the disabled ones.

So, finally, simplify things and keep m_isEnabled in sync with the real
box state, even if this, counter-intuitively, means that IsEnabled() on
the box returns true after calling Enable(false) on it.

This also reverts 4ee35cf5ee569b6ee6c7d0d5702484d4d2a20f96 ("Don't
disable wxStaticBox children at wx level when disabling it") as we can't
avoid really disabling the children any more now that their parent is
not disabled: without this, their IsEnabled() would return true, i.e.
they wouldn't be disabled at all, from the program point of view. This
is unfortunate for the reasons that originally motivated that commit,
i.e. if some wxStaticBox child is disabled, disabling and re-enabling
the box will now re-enable this child, even if it shouldn't, but seems
impossible to avoid. The only possible alternative is to modify
IsEnabled() to add some wxStaticBox-specific hook to it, e.g. instead of
calling GetParent()->IsEnabled() there, we could call some now
AreChildrenEnable() method, which would delegate to IsEnabled() by
default but overridden in wxStaticBox. However this seems complicated,
and will add an extra virtual function call to all (frequently
happening) IsEnabled() calls.
2018-01-18 23:28:16 +01:00

203 lines
7.8 KiB
Objective-C

/////////////////////////////////////////////////////////////////////////////
// Name: statbox.h
// Purpose: interface of wxStaticBox
// Author: wxWidgets team
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
/**
@class wxStaticBox
A static box is a rectangle drawn around other windows to denote
a logical grouping of items.
Note that while the previous versions required that windows appearing
inside a static box be created as its siblings (i.e. use the same parent as
the static box itself), since wxWidgets 2.9.1 it is also possible to create
them as children of wxStaticBox itself and you are actually encouraged to
do it like this if compatibility with the previous versions is not
important.
So the new recommended way to create static box is:
@code
void MyFrame::CreateControls()
{
wxPanel *panel = new wxPanel(this);
wxStaticBox *box = new wxStaticBox(panel, wxID_ANY, "StaticBox");
new wxStaticText(box, wxID_ANY "This window is a child of the staticbox");
...
}
@endcode
While the compatible -- and now deprecated -- way is
@code
wxStaticBox *box = new wxStaticBox(panel, wxID_ANY, "StaticBox");
new wxStaticText(panel, wxID_ANY "This window is a child of the panel");
...
@endcode
Also note that there is a specialized wxSizer class (wxStaticBoxSizer) which can
be used as an easier way to pack items into a static box.
@library{wxcore}
@category{ctrl}
@appearance{staticbox}
@see wxStaticText, wxStaticBoxSizer
*/
class wxStaticBox : public wxControl
{
public:
/**
Default constructor
*/
wxStaticBox();
/**
Constructor, creating and showing a static box.
@param parent
Parent window. Must not be @NULL.
@param id
Window identifier. The value wxID_ANY indicates a default value.
@param label
Text to be displayed in the static box, the empty string for no label.
@param pos
Window position.
If ::wxDefaultPosition is specified then a default position is chosen.
@param size
Checkbox size.
If ::wxDefaultSize is specified then a default size is chosen.
@param style
Window style. There are no wxStaticBox-specific styles, but generic
::wxALIGN_LEFT, ::wxALIGN_CENTRE_HORIZONTAL and ::wxALIGN_RIGHT can
be used here to change the position of the static box label when
using wxGTK (these styles are ignored under the other platforms
currently).
@param name
Window name.
@see Create()
*/
wxStaticBox(wxWindow* parent, wxWindowID id,
const wxString& label,
const wxPoint& pos = wxDefaultPosition,
const wxSize& size = wxDefaultSize,
long style = 0,
const wxString& name = wxStaticBoxNameStr);
/**
Constructor for a static box using the given window as label.
This constructor takes a pointer to an arbitrary window (although
usually a wxCheckBox or a wxRadioButton) instead of just the usual text
label and puts this window at the top of the box at the place where the
label would be shown.
The @a label window must be a non-null, fully created window and will
become a child of this wxStaticBox, i.e. it will be owned by this
control and will be deleted when the wxStaticBox itself is deleted.
An example of creating a wxStaticBox with window as a label:
@code
void MyFrame::CreateControls()
{
wxPanel* panel = new wxPanel(this);
wxCheckBox* checkbox = new wxCheckBox(panel, wxID_ANY, "Box checkbox");
wxStaticBox* box = new wxStaticBox(panel, wxID_ANY, checkbox);
...
}
@endcode
Currently this constructor is only available in wxGTK and wxMSW, use
@c wxHAS_WINDOW_LABEL_IN_STATIC_BOX to check whether it can be used at
compile-time.
@since 3.1.1
*/
wxStaticBox(wxWindow* parent, wxWindowID id,
wxWindow* label,
const wxPoint& pos = wxDefaultPosition,
const wxSize& size = wxDefaultSize,
long style = 0,
const wxString& name = wxStaticBoxNameStr);
/**
Destructor, destroying the group box.
*/
virtual ~wxStaticBox();
/**
Creates the static box for two-step construction.
See wxStaticBox() for further details.
*/
bool Create(wxWindow* parent, wxWindowID id, const wxString& label,
const wxPoint& pos = wxDefaultPosition,
const wxSize& size = wxDefaultSize, long style = 0,
const wxString& name = wxStaticBoxNameStr);
/**
Creates the static box with the window as a label.
This method can only be called for an object created using its default
constructor.
See the constructor documentation for more details.
Currently this overload is only available in wxGTK and wxMSW, use
@c wxHAS_WINDOW_LABEL_IN_STATIC_BOX to check whether it can be used at
compile-time.
@since 3.1.1
*/
bool Create(wxWindow* parent, wxWindowID id,
wxWindow* label,
const wxPoint& pos = wxDefaultPosition,
const wxSize& size = wxDefaultSize,
long style = 0,
const wxString& name = wxStaticBoxNameStr);
/**
Enables or disables the box without affecting its label window, if any.
wxStaticBox overrides wxWindow::Enable() in order to avoid disabling
the control used as a label, if this box is using one. This is done in
order to allow using a wxCheckBox, for example, label and enable or
disable the box according to the state of the checkbox: if disabling
the box also disabled the checkbox in this situation, it would make it
impossible for the user to re-enable the box after disabling it, so the
checkbox stays enabled even if @c box->Enable(false) is called.
However with the actual behaviour, implemented in this overridden
method, the following code (shown using C++11 only for convenience,
this behaviour is not C++11-specific):
@code
auto check = new wxCheckBox(parent, wxID_ANY, "Use the box");
auto box = new wxStaticBox(parent, wxID_ANY, check);
check->Bind(wxEVT_CHECKBOX,
[box](wxCommandEvent& event) {
box->Enable(event.IsChecked());
});
@endcode
does work as expected.
Please note that overriding Enable() to not actually disable this
window itself has two possibly unexpected consequences:
- The box retains its enabled status, i.e. IsEnabled() still returns
@true, after calling @c Enable(false).
- The box children are enabled or disabled when the box is, which can
result in the loss of their original state. E.g. if a box child is
initially disabled, then the box itself is disabled and, finally, the
box is enabled again, this child will end up being enabled too (this
wouldn't happen with any other parent window as its children would
inherit the disabled state from the parent instead of being really
disabled themselves when it is disabled). To avoid this problem,
consider using ::wxEVT_UPDATE_UI to ensure that the child state is
always correct or restoring it manually after re-enabling the box.
*/
virtual bool Enable(bool enable = true);
};