wxWidgets/interface/wx/progdlg.h
Vadim Zeitlin 80ca6661d4 Explain that wxProgressDialog should be created on the stack
Creating it on the heap is unnecessary and can be actually harmful, so
document explicitly that it shouldn't be done.

See #17983.
2017-11-16 01:35:53 +01:00

250 lines
9.2 KiB
Objective-C

/////////////////////////////////////////////////////////////////////////////
// Name: progdlg.h
// Purpose: interface of wxProgressDialog
// Author: wxWidgets team
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#define wxPD_CAN_ABORT 0x0001
#define wxPD_APP_MODAL 0x0002
#define wxPD_AUTO_HIDE 0x0004
#define wxPD_ELAPSED_TIME 0x0008
#define wxPD_ESTIMATED_TIME 0x0010
#define wxPD_SMOOTH 0x0020
#define wxPD_REMAINING_TIME 0x0040
#define wxPD_CAN_SKIP 0x0080
/**
@class wxGenericProgressDialog
This class represents a dialog that shows a short message and a
progress bar. Optionally, it can display ABORT and SKIP buttons, and
the elapsed, remaining and estimated time for the end of the progress.
This class provides a generic implementation of the progress dialog. If
the platform has a native progress dialog available then it will be
accessible using the @a wxProgressDialog class, otherwise it will
essentially be the same as this class.
Note that you must be aware that wxProgressDialog internally calls
wxEventLoopBase::YieldFor with @c wxEVT_CATEGORY_UI and @c wxEVT_CATEGORY_USER_INPUT
and this may cause unwanted re-entrancies or the out-of-order processing
of pending events (to help preventing the last problem if you're using
wxProgressDialog in a multi-threaded application you should be sure to use
wxThreadEvent for your inter-threads communications).
Although wxProgressDialog is not really modal, it should be created on the
stack, and not the heap, as other modal dialogs, e.g. use it like this:
@code
void MyFrame::SomeFunc()
{
wxProgressDialog dialog(...);
for ( int i = 0; i < 100; ++i ) {
if ( !dialog.Update(i)) {
// Cancelled by user.
break;
}
... do something time-consuming (but not too much) ...
}
}
@endcode
@beginStyleTable
@style{wxPD_APP_MODAL}
Make the progress dialog modal. If this flag is not given, it is
only "locally" modal - that is the input to the parent window is
disabled, but not to the other ones.
@style{wxPD_AUTO_HIDE}
Causes the progress dialog to disappear from screen as soon as the
maximum value of the progress meter has been reached.
If this style is not present, the dialog will become a modal dialog
(see wxDialog::ShowModal) once the maximum value has been reached
and wait for the user to dismiss it.
@style{wxPD_SMOOTH}
Causes smooth progress of the gauge control (uses a wxGauge with the
@c wxGA_SMOOTH style).
@style{wxPD_CAN_ABORT}
This flag tells the dialog that it should have a "Cancel" button
which the user may press. If this happens, the next call to
Update() will return @false.
@style{wxPD_CAN_SKIP}
This flag tells the dialog that it should have a "Skip" button
which the user may press. If this happens, the next call to
Update() will return @true in its skip parameter.
@style{wxPD_ELAPSED_TIME}
This flag tells the dialog that it should show elapsed time (since
creating the dialog).
@style{wxPD_ESTIMATED_TIME}
This flag tells the dialog that it should show estimated time.
@style{wxPD_REMAINING_TIME}
This flag tells the dialog that it should show remaining time.
@endStyleTable
@library{wxcore}
@category{cmndlg}
*/
class wxGenericProgressDialog : public wxDialog
{
public:
/**
Constructor. Creates the dialog, displays it and disables user input
for other windows, or, if @c wxPD_APP_MODAL flag is not given, for its
parent window only.
@param title
Dialog title to show in titlebar.
@param message
Message displayed above the progress bar.
@param maximum
Maximum value for the progress bar.
In the generic implementation the progress bar is constructed
only if this value is greater than zero.
@param parent
Parent window.
@param style
The dialog style. See wxProgressDialog.
*/
wxGenericProgressDialog(const wxString& title, const wxString& message,
int maximum = 100,
wxWindow* parent = NULL,
int style = wxPD_AUTO_HIDE | wxPD_APP_MODAL);
/**
Destructor. Deletes the dialog and enables all top level windows.
*/
virtual ~wxGenericProgressDialog();
/**
Returns the last value passed to the Update() function or
@c wxNOT_FOUND if the dialog has no progress bar.
@since 2.9.0
*/
int GetValue() const;
/**
Returns the maximum value of the progress meter, as passed to
the constructor or @c wxNOT_FOUND if the dialog has no progress bar.
@since 2.9.0
*/
int GetRange() const;
/**
Returns the last message passed to the Update() function;
if you always passed wxEmptyString to Update() then the message
set through the constructor is returned.
@since 2.9.0
*/
wxString GetMessage() const;
/**
Like Update() but makes the gauge control run in indeterminate mode.
In indeterminate mode the remaining and the estimated time labels (if
present) are set to "Unknown" or to @a newmsg (if it's non-empty).
Each call to this function moves the progress bar a bit to indicate
that some progress was done.
@see wxGauge::Pulse(), Update()
*/
virtual bool Pulse(const wxString& newmsg = wxEmptyString, bool* skip = NULL);
/**
Can be used to continue with the dialog, after the user had clicked the "Abort" button.
*/
void Resume();
/**
Changes the maximum value of the progress meter given in the constructor.
This function can only be called (with a positive value) if the value passed
in the constructor was positive.
@since 2.9.1
*/
void SetRange(int maximum);
/**
Returns true if the "Cancel" button was pressed.
Normally a Cancel button press is indicated by Update() returning
@false but sometimes it may be more convenient to check if the dialog
was cancelled from elsewhere in the code and this function allows to
do it.
It always returns @false if the Cancel button is not shown at all.
@since 2.9.1
*/
bool WasCancelled() const;
/**
Returns true if the "Skip" button was pressed.
This is similar to WasCancelled() but returns @true if the "Skip"
button was pressed, not the "Cancel" one.
@since 2.9.1
*/
bool WasSkipped() const;
/**
Updates the dialog, setting the progress bar to the new value and
updating the message if new one is specified.
Returns @true unless the "Cancel" button has been pressed.
If @false is returned, the application can either immediately destroy the
dialog or ask the user for the confirmation and if the abort is not confirmed
the dialog may be resumed with Resume() function.
If @a value is the maximum value for the dialog, the behaviour of the
function depends on whether @c wxPD_AUTO_HIDE was used when the dialog
was created. If it was, the dialog is hidden and the function returns
immediately. If it was not, the dialog becomes a modal dialog and waits
for the user to dismiss it, meaning that this function does not return
until this happens.
Notice that if @a newmsg is longer than the currently shown message,
the dialog size will be automatically increased to account for it.
However if the new message is shorter than the previous one, the dialog
doesn't shrink back to avoid constant resizes if the message is changed
often. To shrink back the dialog to fit its current contents you may
call Fit() explicitly.
@param value
The new value of the progress meter. It should be less than or equal to
the maximum value given to the constructor.
@param newmsg
The new messages for the progress dialog text, if it is
empty (which is the default) the message is not changed.
@param skip
If "Skip" button was pressed since last Update() call,
this is set to @true.
*/
virtual bool Update(int value, const wxString& newmsg = wxEmptyString,
bool* skip = NULL);
};
/**
@class wxProgressDialog
If supported by the platform this class will provide the platform's native
progress dialog, else it will simply be the @a wxGenericProgressDialog.
*/
class wxProgressDialog : public wxGenericProgressDialog
{
public:
wxProgressDialog( const wxString& title, const wxString& message,
int maximum = 100,
wxWindow *parent = NULL,
int style = wxPD_APP_MODAL | wxPD_AUTO_HIDE );
};