interface/wx/mediactrl.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        mediactrl.h
   3 // Purpose:     interface of wxMediaEvent, wxMediaCtrl
   4 // Author:      wxWidgets team
   5 // Licence:     wxWindows licence
   6 /////////////////////////////////////////////////////////////////////////////
   7
   8
   9 enum wxMediaCtrlPlayerControls
  10 {
  11     /** No controls. return wxMediaCtrl to its default state. */
  12     wxMEDIACTRLPLAYERCONTROLS_NONE           =   0,
  13
  14     /** Step controls like fastforward, step one frame etc. */
  15     wxMEDIACTRLPLAYERCONTROLS_STEP           =   1 << 0,
  16
  17     /** Volume controls like the speaker icon, volume slider, etc. */
  18     wxMEDIACTRLPLAYERCONTROLS_VOLUME         =   1 << 1,
  19
  20     /** Default controls for the toolkit. Currently a combination for
  21         @c wxMEDIACTRLPLAYERCONTROLS_STEP and @c wxMEDIACTRLPLAYERCONTROLS_VOLUME. */
  22     wxMEDIACTRLPLAYERCONTROLS_DEFAULT        =
  23                     wxMEDIACTRLPLAYERCONTROLS_STEP |
  24                     wxMEDIACTRLPLAYERCONTROLS_VOLUME
  25 };
  26
  27 /**
  28     @class wxMediaEvent
  29
  30     Event wxMediaCtrl uses.
  31
  32     @beginEventTable{wxMediaEvent}
  33     @event{EVT_MEDIA_LOADED(id\, func)}
  34            Sent when a media has loaded enough data that it can start playing.
  35     @event{EVT_MEDIA_STOP(id\, func)}
  36            Sent when a media has switched to the @c wxMEDIASTATE_STOPPED state.
  37            You may be able to Veto this event to prevent it from stopping,
  38            causing it to continue playing - even if it has reached that end of
  39            the media (note that this may not have the desired effect - if you
  40            want to loop the media, for example, catch the @c EVT_MEDIA_FINISHED
  41            and play there instead).
  42     @event{EVT_MEDIA_FINISHED(id\, func)}
  43            Sent when a media has finished playing in a wxMediaCtrl.
  44     @event{EVT_MEDIA_STATECHANGED(id\, func)}
  45            Sent when a media has switched its state (from any media state).
  46     @event{EVT_MEDIA_PLAY(id\, func)}
  47            Sent when a media has switched to the @c wxMEDIASTATE_PLAYING state.
  48     @event{EVT_MEDIA_PAUSE(id\, func)}
  49            Sent when a media has switched to the @c wxMEDIASTATE_PAUSED state.
  50     @endEventTable
  51
  52     @library{wxmedia}
  53     @category{events}
  54 */
  55 class wxMediaEvent : public wxNotifyEvent
  56 {
  57 public:
  58     /** Default ctor. */
  59     wxMediaEvent(wxEventType commandType = wxEVT_NULL, int winid = 0);
  60 };
  61
  62
  63
  64 /**
  65     @class wxMediaCtrl
  66
  67     wxMediaCtrl is a class for displaying types of media, such as videos, audio
  68     files, natively through native codecs.
  69
  70     wxMediaCtrl uses native backends to render media, for example on Windows
  71     there is a ActiveMovie/DirectShow backend, and on Macintosh there is a
  72     QuickTime backend.
  73
  74
  75     @section mediactrl_rendering_media Rendering media
  76
  77     Depending upon the backend, wxMediaCtrl can render and display pretty much any
  78     kind of media that the native system can - such as an image, mpeg video, or mp3
  79     (without license restrictions - since it relies on native system calls that may
  80     not technically have mp3 decoding available, for example, it falls outside
  81     the realm of licensing restrictions).
  82
  83     For general operation, all you need to do is call Load() to load the file you
  84     want to render, catch the @c EVT_MEDIA_LOADED event, and then call Play()
  85     to show the video/audio of the media in that event.
  86
  87     More complex operations are generally more heavily dependent on the capabilities
  88     of the backend. For example, QuickTime cannot set the playback rate of certain
  89     streaming media - while DirectShow is slightly more flexible in that regard.
  90
  91     @section mediactrl_operation Operation
  92
  93     When wxMediaCtrl plays a file, it plays until the stop position is reached
  94     (currently the end of the file/stream). Right before it hits the end of the stream,
  95     it fires off a @c EVT_MEDIA_STOP event to its parent window, at which point the event
  96     handler can choose to veto the event, preventing the stream from actually stopping.
  97
  98     Example:
  99
 100     @code
 101     //connect to the media event
 102     this->Connect(wxMY_ID, wxEVT_MEDIA_STOP, (wxObjectEventFunction)
 103     (wxEventFunction)(wxMediaEventFunction) &MyFrame::OnMediaStop);
 104
 105     //...
 106     void MyFrame::OnMediaStop(const wxMediaEvent& evt)
 107     {
 108         if(bUserWantsToSeek)
 109         {
 110             m_mediactrl->SetPosition(
 111                 m_mediactrl->GetDuration() << 1
 112                                     );
 113             evt.Veto();
 114         }
 115     }
 116     @endcode
 117
 118     When wxMediaCtrl stops, either by the @c EVT_MEDIA_STOP not being vetoed, or
 119     by manually calling Stop(), where it actually stops is not at the beginning,
 120     rather, but at the beginning of the stream. That is, when it stops and play
 121     is called, playback is guaranteed to start at the beginning of the media.
 122     This is because some streams are not seekable, and when stop is called on
 123     them they return to the beginning, thus wxMediaCtrl tries to keep consistent
 124     for all types of media.
 125
 126     Note that when changing the state of the media through Play() and other methods,
 127     the media may not actually be in the @c wxMEDIASTATE_PLAYING, for example.
 128     If you are relying on the media being in certain state catch the event relevant
 129     to the state. See wxMediaEvent for the kinds of events that you can catch.
 130
 131
 132     @section mediactrl_video_size Video size
 133
 134     By default, wxMediaCtrl will scale the size of the video to the requested
 135     amount passed to either its constructor or Create().
 136     After calling wxMediaCtrl::Load or performing an equivalent operation,
 137     you can subsequently obtain the "real" size of the video (if there is any)
 138     by calling wxMediaCtrl::GetBestSize(). Note that the actual result on the
 139     display will be slightly different when wxMediaCtrl::ShowPlayerControls is
 140     activated and the actual video size will be less than specified due to the
 141     extra controls provided by the native toolkit.
 142     In addition, the backend may modify wxMediaCtrl::GetBestSize() to include
 143     the size of the extra controls - so if you want the real size of the video
 144     just disable wxMediaCtrl::ShowPlayerControls().
 145
 146     The idea with setting wxMediaCtrl::GetBestSize() to the size of the video is
 147     that GetBestSize() is a wxWindow-derived function that is called when sizers
 148     on a window recalculate.
 149     What this means is that if you use sizers by default the video will show in
 150     its original size without any extra assistance needed from the user.
 151
 152
 153     @section mediactrl_player_controls Player controls
 154
 155     Normally, when you use wxMediaCtrl it is just a window for the video to play in.
 156     However, some toolkits have their own media player interface.
 157     For example, QuickTime generally has a bar below the video with a slider.
 158     A special feature available to wxMediaCtrl, you can use the toolkits interface
 159     instead of making your own by using the ShowPlayerControls() function.
 160     There are several options for the flags parameter, with the two general flags
 161     being @c wxMEDIACTRLPLAYERCONTROLS_NONE which turns off the native interface,
 162     and @c wxMEDIACTRLPLAYERCONTROLS_DEFAULT which lets wxMediaCtrl decide what
 163     native controls on the interface.
 164     Be sure to review the caveats outlined in @ref mediactrl_video_size before doing so.
 165
 166
 167     @section mediactrl_choosing_backend Choosing a backend
 168
 169     Generally, you should almost certainly leave this part up to wxMediaCtrl -
 170     but if you need a certain backend for a particular reason, such as QuickTime
 171     for playing .mov files, all you need to do to choose a specific backend is
 172     to pass the name of the backend class to wxMediaCtrl::Create().
 173
 174     The following are valid backend identifiers:
 175
 176     - @b wxMEDIABACKEND_DIRECTSHOW: Use ActiveMovie/DirectShow.
 177       Uses the native ActiveMovie (I.E. DirectShow) control.
 178       Default backend on Windows and supported by nearly all Windows versions,
 179       even some Windows CE versions.
 180       May display a windows media player logo while inactive.
 181     - @b wxMEDIABACKEND_QUICKTIME: Use QuickTime. Mac Only.
 182       WARNING: May not working correctly embedded in a wxNotebook.
 183     - @b wxMEDIABACKEND_GSTREAMER, Use GStreamer. Unix Only.
 184       Requires GStreamer 0.8 along with at the very least the xvimagesink, xoverlay,
 185       and gst-play modules of gstreamer to function.
 186       You need the correct modules to play the relevant files, for example the
 187       mad module to play mp3s, etc.
 188     - @b wxMEDIABACKEND_WMP10, Uses Windows Media Player 10 (Windows only) -
 189       works on mobile machines with Windows Media Player 10 and desktop machines
 190       with either Windows Media Player 9 or 10.
 191
 192     Note that other backends such as wxMEDIABACKEND_MCI can now be found at
 193     wxCode (http://wxcode.sourceforge.net/).
 194
 195
 196     @section mediactrl_creating_backend Creating a backend
 197
 198     Creating a backend for wxMediaCtrl is a rather simple process.
 199     Simply derive from wxMediaBackendCommonBase and implement the methods you want.
 200     The methods in wxMediaBackend correspond to those in wxMediaCtrl except for
 201     wxMediaCtrl::CreateControl which does the actual creation of the control,
 202     in cases where a custom control is not needed you may simply call wxControl::Create().
 203
 204     You need to make sure to use the @c DECLARE_CLASS and @c IMPLEMENT_CLASS macros.
 205
 206     The only real tricky part is that you need to make sure the file in compiled in,
 207     which if there are just backends in there will not happen and you may need to
 208     use a force link hack (see http://www.wxwidgets.org/wiki/index.php/RTTI).
 209
 210     This is a rather simple example of how to create a backend in the
 211     wxActiveXContainer documentation.
 212
 213
 214     @library{wxmedia}
 215     @category{media}
 216
 217     @see wxMediaEvent
 218 */
 219 class wxMediaCtrl : public wxControl
 220 {
 221 public:
 222     /**
 223         Default constructor - you MUST call Create() before calling any
 224         other methods of wxMediaCtrl.
 225     */
 226     wxMediaCtrl();
 227
 228     /**
 229         Constructor that calls Create().
 230         You may prefer to call Create() directly to check to see if
 231         wxMediaCtrl is available on the system.
 232
 233         @param parent
 234             parent of this control.  Must not be @NULL.
 235         @param id
 236             id to use for events
 237         @param fileName
 238             If not empty, the path of a file to open.
 239         @param pos
 240             Position to put control at.
 241         @param size
 242             Size to put the control at and to stretch movie to.
 243         @param style
 244             Optional styles.
 245         @param szBackend
 246             Name of backend you want to use, leave blank to make wxMediaCtrl figure it out.
 247         @param validator
 248             validator to use.
 249         @param name
 250             Window name.
 251     */
 252     wxMediaCtrl(wxWindow* parent, wxWindowID id, const wxString& fileName = wxEmptyString,
 253                 const wxPoint& pos = wxDefaultPosition, const wxSize& size = wxDefaultSize,
 254                 long style = 0, const wxString& szBackend = wxEmptyString,
 255                 const wxValidator& validator = wxDefaultValidator,
 256                 const wxString& name = "mediaCtrl");
 257
 258     /**
 259         Creates this control.
 260         Returns @false if it can't load the movie located at @a fileName
 261         or it cannot load one of its native backends.
 262
 263         If you specify a file to open via @a fileName and you don't specify a
 264         backend to use, wxMediaCtrl tries each of its backends until one that
 265         can render the path referred to by @a fileName can be found.
 266
 267         @param parent
 268             parent of this control.  Must not be @NULL.
 269         @param id
 270             id to use for events
 271         @param fileName
 272             If not empty, the path of a file to open.
 273         @param pos
 274             Position to put control at.
 275         @param size
 276             Size to put the control at and to stretch movie to.
 277         @param style
 278             Optional styles.
 279         @param szBackend
 280             Name of backend you want to use, leave blank to make wxMediaCtrl figure it out.
 281         @param validator
 282             validator to use.
 283         @param name
 284             Window name.
 285     */
 286     bool Create(wxWindow* parent, wxWindowID id, const wxString& fileName = wxEmptyString,
 287                 const wxPoint& pos = wxDefaultPosition, const wxSize& size = wxDefaultSize,
 288                 long style = 0, const wxString& szBackend = wxEmptyString,
 289                 const wxValidator& validator = wxDefaultValidator,
 290                 const wxString& name = "mediaCtrl");
 291
 292     /**
 293         Obtains the best size relative to the original/natural size of the
 294         video, if there is any.
 295         See @ref mediactrl_video_size for more information.
 296     */
 297     wxSize GetBestSize() const;
 298
 299     /**
 300         Obtains the playback rate, or speed of the media. @c 1.0 represents normal
 301         speed, while @c 2.0 represents twice the normal speed of the media, for
 302         example. Not supported on the GStreamer (Unix) backend.
 303
 304         @return zero on failure.
 305     */
 306     double GetPlaybackRate();
 307
 308     /**
 309         Obtains the state the playback of the media is in -
 310
 311         @beginTable
 312         @row2col{wxMEDIASTATE_STOPPED, The movie has stopped.}
 313         @row2col{wxMEDIASTATE_PAUSED, The movie is paused.}
 314         @row2col{wxMEDIASTATE_PLAYING, The movie is currently playing.}
 315         @endTable
 316     */
 317     wxMediaState GetState();
 318
 319     /**
 320         Gets the volume of the media from a 0.0 to 1.0 range.
 321
 322         @note Due to rounding and other errors the value returned may not be the
 323               exact value sent to SetVolume().
 324     */
 325     double GetVolume();
 326
 327     /**
 328         Obtains the length - the total amount of time the movie has in milliseconds.
 329     */
 330     wxFileOffset Length();
 331
 332     /**
 333         Loads the file that fileName refers to. Returns @false if loading fails.
 334     */
 335     bool Load(const wxString& fileName);
 336
 337     /**
 338         Loads the location that uri refers to. Note that this is very
 339         implementation-dependent, although HTTP URI/URLs are generally
 340         supported, for example. Returns @false if loading fails.
 341     */
 342     bool Load(const wxURI& uri);
 343
 344     /**
 345         Loads the location that @c uri refers to with the proxy @c proxy.
 346         Not implemented on most backends so it should be called with caution.
 347         Returns @false if loading fails.
 348     */
 349     bool Load(const wxURI& uri, const wxURI& proxy);
 350
 351     /**
 352         Same as Load(const wxURI& uri). Kept for wxPython compatibility.
 353     */
 354     bool LoadURI(const wxString& fileName);
 355
 356     /**
 357         Same as Load(const wxURI& uri, const wxURI& proxy).
 358         Kept for wxPython compatibility.
 359     */
 360     bool LoadURIWithProxy(const wxString& fileName, const wxString& proxy);
 361
 362     /**
 363         Pauses playback of the movie.
 364     */
 365     bool Pause();
 366
 367     /**
 368         Resumes playback of the movie.
 369     */
 370     bool Play();
 371
 372     /**
 373         Seeks to a position within the movie.
 374
 375         @todo Document the wxSeekMode parameter @a mode, and perhaps also the
 376               wxFileOffset and wxSeekMode themselves.
 377     */
 378     wxFileOffset Seek(wxFileOffset where, wxSeekMode mode = wxFromStart);
 379
 380     /**
 381         Sets the playback rate, or speed of the media, to that referred by @a dRate.
 382         @c 1.0 represents normal speed, while @c 2.0 represents twice the normal
 383         speed of the media, for example. Not supported on the GStreamer (Unix) backend.
 384         Returns @true if successful.
 385     */
 386     bool SetPlaybackRate(double dRate);
 387
 388     /**
 389         Sets the volume of the media from a 0.0 to 1.0 range to that referred
 390         by @c dVolume.  @c 1.0 represents full volume, while @c 0.5
 391         represents half (50 percent) volume, for example.
 392
 393         @note The volume may not be exact due to conversion and rounding errors,
 394               although setting the volume to full or none is always exact.
 395               Returns @true if successful.
 396     */
 397     bool SetVolume(double dVolume);
 398
 399     /**
 400         A special feature to wxMediaCtrl. Applications using native toolkits such as
 401         QuickTime usually have a scrollbar, play button, and more provided to
 402         them by the toolkit. By default wxMediaCtrl does not do this. However, on
 403         the directshow and quicktime backends you can show or hide the native controls
 404         provided by the underlying toolkit at will using ShowPlayerControls(). Simply
 405         calling the function with default parameters tells wxMediaCtrl to use the
 406         default controls provided by the toolkit. The function takes a
 407         wxMediaCtrlPlayerControls enumeration, please see available show modes there.
 408
 409         For more info see @ref mediactrl_player_controls.
 410
 411         Currently only implemented on the QuickTime and DirectShow backends.
 412         The function returns @true on success.
 413     */
 414     bool ShowPlayerControls(wxMediaCtrlPlayerControls flags = wxMEDIACTRLPLAYERCONTROLS_DEFAULT);
 415
 416     /**
 417         Stops the media.
 418
 419         See @ref mediactrl_operation for an overview of how stopping works.
 420     */
 421     bool Stop();
 422
 423     /**
 424         Obtains the current position in time within the movie in milliseconds.
 425     */
 426     wxFileOffset Tell();
 427 };
 428