| 1 | \section{\class{wxDDEConnection}}\label{wxddeconnection} |
| 2 | |
| 3 | A wxDDEConnection object represents the connection between a client and a |
| 4 | server. It can be created by making a connection using a\rtfsp |
| 5 | \helpref{wxDDEClient}{wxddeclient} object, or by the acceptance of a connection by a\rtfsp |
| 6 | \helpref{wxDDEServer}{wxddeserver} object. The bulk of a DDE (Dynamic Data Exchange) |
| 7 | conversation is controlled by |
| 8 | calling members in a {\bf wxDDEConnection} object or by overriding its |
| 9 | members. |
| 10 | |
| 11 | An application should normally derive a new connection class from |
| 12 | wxDDEConnection, in order to override the communication event handlers |
| 13 | to do something interesting. |
| 14 | |
| 15 | This DDE-based implementation is available on Windows only, |
| 16 | but a platform-independent, socket-based version |
| 17 | of this API is available using \helpref{wxTCPConnection}{wxtcpconnection}. |
| 18 | |
| 19 | \wxheading{Derived from} |
| 20 | |
| 21 | wxConnectionBase\\ |
| 22 | \helpref{wxObject}{wxobject} |
| 23 | |
| 24 | \wxheading{Include files} |
| 25 | |
| 26 | <wx/dde.h> |
| 27 | |
| 28 | \wxheading{Types} |
| 29 | |
| 30 | \index{wxIPCFormat}wxIPCFormat is defined as follows: |
| 31 | |
| 32 | \begin{verbatim} |
| 33 | enum wxIPCFormat |
| 34 | { |
| 35 | wxIPC_INVALID = 0, |
| 36 | wxIPC_TEXT = 1, /* CF_TEXT */ |
| 37 | wxIPC_BITMAP = 2, /* CF_BITMAP */ |
| 38 | wxIPC_METAFILE = 3, /* CF_METAFILEPICT */ |
| 39 | wxIPC_SYLK = 4, |
| 40 | wxIPC_DIF = 5, |
| 41 | wxIPC_TIFF = 6, |
| 42 | wxIPC_OEMTEXT = 7, /* CF_OEMTEXT */ |
| 43 | wxIPC_DIB = 8, /* CF_DIB */ |
| 44 | wxIPC_PALETTE = 9, |
| 45 | wxIPC_PENDATA = 10, |
| 46 | wxIPC_RIFF = 11, |
| 47 | wxIPC_WAVE = 12, |
| 48 | wxIPC_UNICODETEXT = 13, |
| 49 | wxIPC_ENHMETAFILE = 14, |
| 50 | wxIPC_FILENAME = 15, /* CF_HDROP */ |
| 51 | wxIPC_LOCALE = 16, |
| 52 | wxIPC_PRIVATE = 20 |
| 53 | }; |
| 54 | \end{verbatim} |
| 55 | |
| 56 | \wxheading{See also} |
| 57 | |
| 58 | \helpref{wxDDEClient}{wxddeclient}, \helpref{wxDDEServer}{wxddeserver}, \helpref{Interprocess communications overview}{ipcoverview} |
| 59 | |
| 60 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 61 | |
| 62 | \membersection{wxDDEConnection::wxDDEConnection} |
| 63 | |
| 64 | \func{}{wxDDEConnection}{\void} |
| 65 | |
| 66 | \func{}{wxDDEConnection}{\param{char* }{buffer}, \param{int}{ size}} |
| 67 | |
| 68 | Constructs a connection object. If no user-defined connection object is |
| 69 | to be derived from wxDDEConnection, then the constructor should not be |
| 70 | called directly, since the default connection object will be provided on |
| 71 | requesting (or accepting) a connection. However, if the user defines his |
| 72 | or her own derived connection object, the \helpref{wxDDEServer::OnAcceptConnection}{wxddeserveronacceptconnection}\rtfsp |
| 73 | and/or \helpref{wxDDEClient::OnMakeConnection}{wxddeclientonmakeconnection} members should be replaced by |
| 74 | functions which construct the new connection object. If the arguments of |
| 75 | the wxDDEConnection constructor are void, then a default buffer is |
| 76 | associated with the connection. Otherwise, the programmer must provide a |
| 77 | a buffer and size of the buffer for the connection object to use in |
| 78 | transactions. |
| 79 | |
| 80 | \membersection{wxDDEConnection::Advise} |
| 81 | |
| 82 | \func{bool}{Advise}{\param{const wxString\& }{item}, \param{char* }{data}, \param{int}{ size = -1}, \param{wxIPCFormat}{ format = wxCF\_TEXT}} |
| 83 | |
| 84 | Called by the server application to advise the client of a change in |
| 85 | the data associated with the given item. Causes the client |
| 86 | connection's \helpref{wxDDEConnection::OnAdvise}{wxddeconnectiononadvise} |
| 87 | member to be called. Returns TRUE if successful. |
| 88 | |
| 89 | \membersection{wxDDEConnection::Execute} |
| 90 | |
| 91 | \func{bool}{Execute}{\param{char* }{data}, \param{int}{ size = -1}, \param{wxIPCFormat}{ format = wxCF\_TEXT}} |
| 92 | |
| 93 | Called by the client application to execute a command on the server. Can |
| 94 | also be used to transfer arbitrary data to the server (similar |
| 95 | to \helpref{wxDDEConnection::Poke}{wxddeconnectionpoke} in that respect). Causes the |
| 96 | server connection's \helpref{wxDDEConnection::OnExecute}{wxddeconnectiononexecute} member to be |
| 97 | called. Returns TRUE if successful. |
| 98 | |
| 99 | \membersection{wxDDEConnection::Disconnect} |
| 100 | |
| 101 | \func{bool}{Disconnect}{\void} |
| 102 | |
| 103 | Called by the client or server application to disconnect from the other |
| 104 | program; it causes the \helpref{wxDDEConnection::OnDisconnect}{wxddeconnectionondisconnect} message |
| 105 | to be sent to the corresponding connection object in the other |
| 106 | program. The default behaviour of {\bf OnDisconnect} is to delete the |
| 107 | connection, but the calling application must explicitly delete its |
| 108 | side of the connection having called {\bf Disconnect}. Returns TRUE if |
| 109 | successful. |
| 110 | |
| 111 | \membersection{wxDDEConnection::OnAdvise}\label{wxddeconnectiononadvise} |
| 112 | |
| 113 | \func{virtual bool}{OnAdvise}{\param{const wxString\& }{topic}, \param{const wxString\& }{item}, \param{char* }{data}, \param{int}{ size}, \param{wxIPCFormat}{ format}} |
| 114 | |
| 115 | Message sent to the client application when the server notifies it of a |
| 116 | change in the data associated with the given item. |
| 117 | |
| 118 | \membersection{wxDDEConnection::OnDisconnect}\label{wxddeconnectionondisconnect} |
| 119 | |
| 120 | \func{virtual bool}{OnDisconnect}{\void} |
| 121 | |
| 122 | Message sent to the client or server application when the other |
| 123 | application notifies it to delete the connection. Default behaviour is |
| 124 | to delete the connection object. |
| 125 | |
| 126 | \membersection{wxDDEConnection::OnExecute}\label{wxddeconnectiononexecute} |
| 127 | |
| 128 | \func{virtual bool}{OnExecute}{\param{const wxString\& }{topic}, \param{char* }{data}, \param{int}{ size}, \param{wxIPCFormat}{ format}} |
| 129 | |
| 130 | Message sent to the server application when the client notifies it to |
| 131 | execute the given data. Note that there is no item associated with |
| 132 | this message. |
| 133 | |
| 134 | \membersection{wxDDEConnection::OnPoke}\label{wxddeconnectiononpoke} |
| 135 | |
| 136 | \func{virtual bool}{OnPoke}{\param{const wxString\& }{topic}, \param{const wxString\& }{item}, \param{char* }{data}, \param{int}{ size}, \param{wxIPCFormat}{ format}} |
| 137 | |
| 138 | Message sent to the server application when the client notifies it to |
| 139 | accept the given data. |
| 140 | |
| 141 | \membersection{wxDDEConnection::OnRequest}\label{wxddeconnectiononrequest} |
| 142 | |
| 143 | \func{virtual char*}{OnRequest}{\param{const wxString\& }{topic}, \param{const wxString\& }{item}, \param{int *}{size}, \param{wxIPCFormat}{ format}} |
| 144 | |
| 145 | Message sent to the server application when the client |
| 146 | calls \helpref{wxDDEConnection::Request}{wxddeconnectionrequest}. The server |
| 147 | should respond by returning a character string from {\bf OnRequest}, |
| 148 | or NULL to indicate no data. |
| 149 | |
| 150 | \membersection{wxDDEConnection::OnStartAdvise}\label{wxddeconnectiononstartadvise} |
| 151 | |
| 152 | \func{virtual bool}{OnStartAdvise}{\param{const wxString\& }{topic}, \param{const wxString\& }{item}} |
| 153 | |
| 154 | Message sent to the server application by the client, when the client |
| 155 | wishes to start an `advise loop' for the given topic and item. The |
| 156 | server can refuse to participate by returning FALSE. |
| 157 | |
| 158 | \membersection{wxDDEConnection::OnStopAdvise}\label{wxddeconnectiononstopadvise} |
| 159 | |
| 160 | \func{virtual bool}{OnStopAdvise}{\param{const wxString\& }{topic}, \param{const wxString\& }{item}} |
| 161 | |
| 162 | Message sent to the server application by the client, when the client |
| 163 | wishes to stop an `advise loop' for the given topic and item. The |
| 164 | server can refuse to stop the advise loop by returning FALSE, although |
| 165 | this doesn't have much meaning in practice. |
| 166 | |
| 167 | \membersection{wxDDEConnection::Poke}\label{wxddeconnectionpoke} |
| 168 | |
| 169 | \func{bool}{Poke}{\param{const wxString\& }{item}, \param{char* }{data}, \param{int}{ size = -1}, \param{wxIPCFormat}{ format = wxCF\_TEXT}} |
| 170 | |
| 171 | Called by the client application to poke data into the server. Can be |
| 172 | used to transfer arbitrary data to the server. Causes the server |
| 173 | connection's \helpref{wxDDEConnection::OnPoke}{wxddeconnectiononpoke} member |
| 174 | to be called. Returns TRUE if successful. |
| 175 | |
| 176 | \membersection{wxDDEConnection::Request}\label{wxddeconnectionrequest} |
| 177 | |
| 178 | \func{char*}{Request}{\param{const wxString\& }{item}, \param{int *}{size}, \param{wxIPCFormat}{ format = wxIPC\_TEXT}} |
| 179 | |
| 180 | Called by the client application to request data from the server. Causes |
| 181 | the server connection's \helpref{wxDDEConnection::OnRequest}{wxddeconnectiononrequest} member to be called. Returns a |
| 182 | character string (actually a pointer to the connection's buffer) if |
| 183 | successful, NULL otherwise. |
| 184 | |
| 185 | \membersection{wxDDEConnection::StartAdvise}\label{wxddeconnectionstartadvise} |
| 186 | |
| 187 | \func{bool}{StartAdvise}{\param{const wxString\& }{item}} |
| 188 | |
| 189 | Called by the client application to ask if an advise loop can be started |
| 190 | with the server. Causes the server connection's \helpref{wxDDEConnection::OnStartAdvise}{wxddeconnectiononstartadvise}\rtfsp |
| 191 | member to be called. Returns TRUE if the server okays it, FALSE |
| 192 | otherwise. |
| 193 | |
| 194 | \membersection{wxDDEConnection::StopAdvise}\label{wxddeconnectionstopadvise} |
| 195 | |
| 196 | \func{bool}{StopAdvise}{\param{const wxString\& }{item}} |
| 197 | |
| 198 | Called by the client application to ask if an advise loop can be |
| 199 | stopped. Causes the server connection's \helpref{wxDDEConnection::OnStopAdvise}{wxddeconnectiononstopadvise} member |
| 200 | to be called. Returns TRUE if the server okays it, FALSE otherwise. |
| 201 | |
| 202 | |