interface/wx/mediactrl.h

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