fix GetTextExtent with non-null font argument, fixes #13750

[wxWidgets.git] / interface / wx / dialup.h

/////////////////////////////////////////////////////////////////////////////
// Name:        dialup.h
// Purpose:     interface of wxDialUpManager
// Author:      wxWidgets team
// RCS-ID:      $Id$
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

/**
    @class wxDialUpManager

    This class encapsulates functions dealing with verifying the connection
    status of the workstation (connected to the Internet via a direct
    connection, connected through a modem or not connected at all) and to
    establish this connection if possible/required (i.e. in the case of the
    modem).

    The program may also wish to be notified about the change in the connection
    status (for example, to perform some action when the user connects to the
    network the next time or, on the contrary, to stop receiving data from the
    net when the user hangs up the modem). For this, you need to use one of the
    event macros described below.

    This class is different from other wxWidgets classes in that there is at
    most one instance of this class in the program accessed via Create() and
    you can't create the objects of this class directly.

    @beginEventEmissionTable{wxDialUpEvent}
    @event{EVT_DIALUP_CONNECTED(func)}
        A connection with the network was established.
    @event{EVT_DIALUP_DISCONNECTED(func)}
        The connection with the network was lost.
    @endEventTable

    @library{wxcore}
    @category{net}

    @see @ref page_samples_dialup, wxDialUpEvent
*/
class wxDialUpManager
{
public:
    /**
        Destructor.
    */
    virtual ~wxDialUpManager();

    /**
        Cancel dialing the number initiated with Dial() with async parameter
        equal to @true.

        @note This won't result in a DISCONNECTED event being sent.

        @see IsDialing()
    */
    virtual bool CancelDialing() = 0;

    /**
        This function should create and return the object of the
        platform-specific class derived from wxDialUpManager. You should delete
        the pointer when you are done with it.
    */
    static wxDialUpManager* Create();

    /**
        Dial the given ISP, use @a username and @a password to authenticate.

        The parameters are only used under Windows currently, for Unix you
        should use SetConnectCommand() to customize this functions behaviour.

        If no @a nameOfISP is given, the function will select the default one
        (proposing the user to choose among all connections defined on this
        machine) and if no username and/or password are given, the function
        will try to do without them, but will ask the user if really needed.

        If @a async parameter is @false, the function waits until the end of
        dialing and returns @true upon successful completion.

        If @a async is @true, the function only initiates the connection and
        returns immediately - the result is reported via events (an event is
        sent anyhow, but if dialing failed it will be a DISCONNECTED one).
    */
    virtual bool Dial(const wxString& nameOfISP = wxEmptyString,
                      const wxString& username = wxEmptyString,
                      const wxString& password = wxEmptyString,
                      bool async = true) = 0;

    /**
        Disable automatic check for connection status change - notice that the
        @c wxEVT_DIALUP_XXX events won't be sent any more neither.
    */
    virtual void DisableAutoCheckOnlineStatus() = 0;

    /**
        Enable automatic checks for the connection status and sending of
        @c wxEVT_DIALUP_CONNECTED/wxEVT_DIALUP_DISCONNECTED events. The interval
        parameter is only for Unix where we do the check manually and specifies
        how often should we repeat the check (each minute by default). Under
        Windows, the notification about the change of connection status is sent
        by the system and so we don't do any polling and this parameter is
        ignored.

        @return @false if couldn't set up automatic check for online status.
    */
    virtual bool EnableAutoCheckOnlineStatus(size_t nSeconds = 60) = 0;

    /**
        This function is only implemented under Windows.

        Fills the array with the names of all possible values for the first
        parameter to Dial() on this machine and returns their number (may be
        0).
    */
    virtual size_t GetISPNames(wxArrayString& names) const = 0;

    /**
        Hang up the currently active dial up connection.
    */
    virtual bool HangUp() = 0;

    /**
        Returns @true if the computer has a permanent network connection (i.e.
        is on a LAN) and so there is no need to use Dial() function to go
        online.

        @note This function tries to guess the result and it is not always
              guaranteed to be correct, so it is better to ask user for
              confirmation or give him a possibility to override it.
    */
    virtual bool IsAlwaysOnline() const = 0;

    /**
        Returns @true if (async) dialing is in progress.

        @see Dial()
    */
    virtual bool IsDialing() const = 0;

    /**
        Returns @true if the dialup manager was initialized correctly. If this
        function returns @false, no other functions will work neither, so it is
        a good idea to call this function and check its result before calling
        any other wxDialUpManager methods.
    */
    virtual bool IsOk() const = 0;

    /**
        Returns @true if the computer is connected to the network: under
        Windows, this just means that a RAS connection exists, under Unix we
        check that the "well-known host" (as specified by SetWellKnownHost())
        is reachable.
    */
    virtual bool IsOnline() const = 0;

    /**
        This method is for Unix only.

        Sets the commands to start up the network and to hang up again.
    */
    virtual void SetConnectCommand(const wxString& commandDial = "/usr/bin/pon",
                                   const wxString& commandHangup = "/usr/bin/poff") = 0;

    /**
        Sometimes the built-in logic for determining the online status may
        fail, so, in general, the user should be allowed to override it. This
        function allows to forcefully set the online status - whatever our
        internal algorithm may think about it.

        @see IsOnline()
    */
    virtual void SetOnlineStatus(bool isOnline = true) = 0;

    /**
        This method is for Unix only.

        Under Unix, the value of well-known host is used to check whether we're
        connected to the internet. It is unused under Windows, but this
        function is always safe to call. The default value is
        @c "www.yahoo.com:80".
    */
    virtual void SetWellKnownHost(const wxString& hostname,
                                  int portno = 80) = 0;
};



/**
    @class wxDialUpEvent

    This is the event class for the dialup events sent by wxDialUpManager.

    @library{wxcore}
    @category{events}
*/
class wxDialUpEvent : public wxEvent
{
public:
    /**
        Constructor is only used by wxDialUpManager.
    */
    wxDialUpEvent(bool isConnected, bool isOwnEvent);

    /**
        Is this a @c CONNECTED or @c DISCONNECTED event? In other words, does
        it notify about transition from offline to online state or vice versa?
    */
    bool IsConnectedEvent() const;

    /**
        Does this event come from wxDialUpManager::Dial() or from some external
        process (i.e. does it result from our own attempt to establish the
        connection)?
    */
    bool IsOwnEvent() const;
};