src/gtk/clipbrd.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        clipbrd.cpp
   3 // Purpose:
   4 // Author:      Robert Roebling
   5 // Id:          $Id$
   6 // Copyright:   (c) 1998 Robert Roebling
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 #ifdef __GNUG__
  11 #pragma implementation "clipbrd.h"
  12 #endif
  13
  14 #include "wx/clipbrd.h"
  15
  16 #if wxUSE_CLIPBOARD
  17
  18 #include "wx/utils.h"
  19
  20 #include "glib.h"
  21 #include "gdk/gdk.h"
  22 #include "gtk/gtk.h"
  23
  24 //-----------------------------------------------------------------------------
  25 // data
  26 //-----------------------------------------------------------------------------
  27
  28 wxClipboard *wxTheClipboard = (wxClipboard*) NULL;
  29
  30 GdkAtom  g_clipboardAtom   = 0;
  31 GdkAtom  g_targetsAtom     = 0;
  32
  33 //-----------------------------------------------------------------------------
  34 // reminder
  35 //-----------------------------------------------------------------------------
  36
  37 /* The contents of a selection are returned in a GtkSelectionData
  38    structure. selection/target identify the request.
  39    type specifies the type of the return; if length < 0, and
  40    the data should be ignored. This structure has object semantics -
  41    no fields should be modified directly, they should not be created
  42    directly, and pointers to them should not be stored beyond the duration of
  43    a callback. (If the last is changed, we'll need to add reference
  44    counting)
  45
  46 struct _GtkSelectionData
  47 {
  48   GdkAtom selection;
  49   GdkAtom target;
  50   GdkAtom type;
  51   gint    format;
  52   guchar *data;
  53   gint    length;
  54 };
  55
  56 */
  57
  58 //-----------------------------------------------------------------------------
  59 // "selection_received" for targets
  60 //-----------------------------------------------------------------------------
  61
  62 static void
  63 targets_selection_received( GtkWidget *WXUNUSED(widget),
  64                             GtkSelectionData *selection_data,
  65 #if (GTK_MINOR_VERSION > 0)
  66                             guint32 WXUNUSED(time),
  67 #endif
  68                             wxClipboard *clipboard )
  69 {
  70     if (!wxTheClipboard)
  71     {
  72         clipboard->m_waiting = FALSE;
  73         return;
  74     }
  75
  76     if (selection_data->length <= 0)
  77     {
  78         clipboard->m_waiting = FALSE;
  79         return;
  80     }
  81
  82     /* make sure we got the data in the correct form */
  83     if (selection_data->type != GDK_SELECTION_TYPE_ATOM)
  84     {
  85         clipboard->m_waiting = FALSE;
  86         return;
  87     }
  88
  89     // the atoms we received, holding a list of targets (= formats)
  90     GdkAtom *atoms = (GdkAtom *)selection_data->data;
  91
  92     for (unsigned int i=0; i<selection_data->length/sizeof(GdkAtom); i++)
  93     {
  94 /*      char *name = gdk_atom_name (atoms[i]);
  95         if (name) printf( "Format available: %s.\n", name ); */
  96
  97         if (atoms[i] == clipboard->m_targetRequested)
  98         {
  99             clipboard->m_waiting = FALSE;
 100             clipboard->m_formatSupported = TRUE;
 101             return;
 102         }
 103     }
 104
 105     clipboard->m_waiting = FALSE;
 106     return;
 107 }
 108
 109 //-----------------------------------------------------------------------------
 110 // "selection_received" for the actual data
 111 //-----------------------------------------------------------------------------
 112
 113 static void
 114 selection_received( GtkWidget *WXUNUSED(widget),
 115                     GtkSelectionData *selection_data,
 116 #if (GTK_MINOR_VERSION > 0)
 117                     guint32 WXUNUSED(time),
 118 #endif
 119                     wxClipboard *clipboard )
 120 {
 121     if (!wxTheClipboard)
 122     {
 123         clipboard->m_waiting = FALSE;
 124         return;
 125     }
 126
 127     wxDataObject *data_object = clipboard->m_receivedData;
 128
 129     if (!data_object)
 130     {
 131         clipboard->m_waiting = FALSE;
 132         return;
 133     }
 134
 135     if (selection_data->length <= 0)
 136     {
 137         clipboard->m_waiting = FALSE;
 138         return;
 139     }
 140
 141     /* make sure we got the data in the correct format */
 142     if (data_object->GetFormat().GetAtom() != selection_data->target)
 143     {
 144         clipboard->m_waiting = FALSE;
 145         return;
 146     }
 147
 148     /* make sure we got the data in the correct form (selection type).
 149        if so, copy data to target object */
 150
 151     switch (data_object->GetFormat().GetType())
 152     {
 153         case wxDF_TEXT:
 154         {
 155             if (selection_data->type != GDK_SELECTION_TYPE_STRING)
 156             {
 157                 clipboard->m_waiting = FALSE;
 158                 return;
 159             }
 160
 161             wxTextDataObject *text_object = (wxTextDataObject *) data_object;
 162
 163             wxString text = (const char*) selection_data->data;
 164
 165             text_object->SetText( text );
 166
 167             break;
 168         }
 169
 170         case wxDF_BITMAP:
 171         {
 172             if (selection_data->type != GDK_SELECTION_TYPE_BITMAP)
 173             {
 174                 clipboard->m_waiting = FALSE;
 175                 return;
 176             }
 177
 178             break;
 179         }
 180
 181         case wxDF_PRIVATE:
 182         {
 183             if (selection_data->type != GDK_SELECTION_TYPE_STRING)
 184             {
 185                 clipboard->m_waiting = FALSE;
 186                 return;
 187             }
 188
 189             wxPrivateDataObject *private_object = (wxPrivateDataObject *) data_object;
 190
 191             private_object->SetData( (const char*) selection_data->data, (size_t) selection_data->length );
 192
 193             break;
 194         }
 195
 196         default:
 197         {
 198             clipboard->m_waiting = FALSE;
 199             return;
 200         }
 201     }
 202
 203     wxTheClipboard->m_formatSupported = TRUE;
 204     clipboard->m_waiting = FALSE;
 205 }
 206
 207 //-----------------------------------------------------------------------------
 208 // "selection_clear"
 209 //-----------------------------------------------------------------------------
 210
 211 static gint
 212 selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
 213 {
 214     if (!wxTheClipboard) return TRUE;
 215
 216     if (event->selection == GDK_SELECTION_PRIMARY)
 217     {
 218         wxTheClipboard->m_ownsPrimarySelection = FALSE;
 219     }
 220     else
 221     if (event->selection == g_clipboardAtom)
 222     {
 223         wxTheClipboard->m_ownsClipboard = FALSE;
 224     }
 225     else
 226     {
 227         return FALSE;
 228     }
 229
 230     if ((!wxTheClipboard->m_ownsPrimarySelection) &&
 231         (!wxTheClipboard->m_ownsClipboard))
 232     {
 233         /* the clipboard is no longer in our hands. we can the  clipboard data. */
 234
 235         if (wxTheClipboard->m_dataBroker)
 236         {
 237             delete wxTheClipboard->m_dataBroker;
 238             wxTheClipboard->m_dataBroker = (wxDataBroker*) NULL;
 239         }
 240     }
 241
 242     return TRUE;
 243 }
 244
 245 //-----------------------------------------------------------------------------
 246 // selection handler for supplying data
 247 //-----------------------------------------------------------------------------
 248
 249 static void
 250 selection_handler( GtkWidget *WXUNUSED(widget), GtkSelectionData *selection_data, gpointer WXUNUSED(data) )
 251 {
 252     if (!wxTheClipboard) return;
 253
 254     if (!wxTheClipboard->m_dataBroker) return;
 255
 256     wxNode *node = wxTheClipboard->m_dataBroker->m_dataObjects.First();
 257
 258     while (node)
 259     {
 260         wxDataObject *data_object = (wxDataObject *)node->Data();
 261
 262         if (data_object->GetFormat().GetAtom() != selection_data->target)
 263         {
 264             node = node->Next();
 265             break;
 266         }
 267
 268         switch (data_object->GetFormat().GetType())
 269         {
 270             case wxDF_TEXT:
 271             {
 272                 wxTextDataObject *text_object = (wxTextDataObject*) data_object;
 273
 274                 wxString text = text_object->GetText();
 275
 276 #if wxUSE_UNICODE
 277                 const wxWX2MBbuf s = text.mbc_str();
 278                 int len = strlen(s);
 279 #else // more efficient in non-Unicode
 280                 const char *s = text.c_str();
 281                 int len = (int) text.Length();
 282 #endif
 283
 284                 gtk_selection_data_set(
 285                     selection_data,
 286                     GDK_SELECTION_TYPE_STRING,
 287                     8*sizeof(gchar),
 288                     (unsigned char*) (const char*) s,
 289                     len );
 290
 291                 break;
 292             }
 293
 294             case wxDF_BITMAP:
 295             {
 296                 // wxBitmapDataObject *private_object = (wxBitmapDataObject*) data_object;
 297
 298                 // how do we do that ?
 299
 300                 break;
 301             }
 302
 303             case wxDF_PRIVATE:
 304             {
 305                 wxPrivateDataObject *private_object = (wxPrivateDataObject*) data_object;
 306
 307                 if (private_object->GetSize() == 0) return;
 308
 309                 gtk_selection_data_set(
 310                     selection_data,
 311                     GDK_SELECTION_TYPE_STRING,
 312                     8*sizeof(gchar),
 313                     (unsigned char*) private_object->GetData(),
 314                     (int) private_object->GetSize() );
 315             }
 316
 317             default:
 318               break;
 319         }
 320
 321         node = node->Next();
 322     }
 323 }
 324
 325 //-----------------------------------------------------------------------------
 326 // wxClipboard
 327 //-----------------------------------------------------------------------------
 328
 329 IMPLEMENT_DYNAMIC_CLASS(wxClipboard,wxObject)
 330
 331 wxClipboard::wxClipboard()
 332 {
 333     m_open = FALSE;
 334
 335     m_ownsClipboard = FALSE;
 336     m_ownsPrimarySelection = FALSE;
 337
 338     m_dataBroker = (wxDataBroker*) NULL;
 339
 340     m_receivedData = (wxDataObject*) NULL;
 341
 342     /* we use m_targetsWidget to query what formats are available */
 343
 344     m_targetsWidget = gtk_window_new( GTK_WINDOW_POPUP );
 345     gtk_widget_realize( m_targetsWidget );
 346
 347     gtk_signal_connect( GTK_OBJECT(m_targetsWidget),
 348                         "selection_received",
 349                         GTK_SIGNAL_FUNC( targets_selection_received ),
 350                         (gpointer) this );
 351
 352     /* we use m_clipboardWidget to get and to offer data */
 353
 354     m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
 355     gtk_widget_realize( m_clipboardWidget );
 356
 357     gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
 358                         "selection_received",
 359                         GTK_SIGNAL_FUNC( selection_received ),
 360                         (gpointer) this );
 361
 362     gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
 363                         "selection_clear_event",
 364                         GTK_SIGNAL_FUNC( selection_clear_clip ),
 365                         (gpointer) NULL );
 366
 367     if (!g_clipboardAtom) g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
 368     if (!g_targetsAtom) g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
 369
 370     m_formatSupported = FALSE;
 371     m_targetRequested = 0;
 372 }
 373
 374 wxClipboard::~wxClipboard()
 375 {
 376     Clear();
 377
 378     if (m_clipboardWidget) gtk_widget_destroy( m_clipboardWidget );
 379     if (m_targetsWidget) gtk_widget_destroy( m_targetsWidget );
 380 }
 381
 382 void wxClipboard::Clear()
 383 {
 384     if (m_dataBroker)
 385     {
 386         /*  As we have data we also own the clipboard. Once we no longer own
 387             it, clear_selection is called which will set m_data to zero */
 388
 389         if (gdk_selection_owner_get( g_clipboardAtom ) == m_clipboardWidget->window)
 390         {
 391             gtk_selection_owner_set( (GtkWidget*) NULL, g_clipboardAtom, GDK_CURRENT_TIME );
 392         }
 393
 394         if (gdk_selection_owner_get( GDK_SELECTION_PRIMARY ) == m_clipboardWidget->window)
 395         {
 396             gtk_selection_owner_set( (GtkWidget*) NULL, GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME );
 397         }
 398
 399         if (m_dataBroker)
 400         {
 401             delete m_dataBroker;
 402             m_dataBroker = (wxDataBroker*) NULL;
 403         }
 404     }
 405
 406     m_targetRequested = 0;
 407
 408     m_formatSupported = FALSE;
 409 }
 410
 411 bool wxClipboard::Open()
 412 {
 413     wxCHECK_MSG( !m_open, FALSE, _T("clipboard already open") );
 414
 415     m_open = TRUE;
 416
 417     return TRUE;
 418 }
 419
 420 bool wxClipboard::SetData( wxDataObject *data )
 421 {
 422     wxCHECK_MSG( m_open, FALSE, _T("clipboard not open") );
 423
 424     wxCHECK_MSG( data, FALSE, _T("data is invalid") );
 425
 426     Clear();
 427
 428     return AddData( data );
 429 }
 430
 431 bool wxClipboard::AddData( wxDataObject *data )
 432 {
 433     wxCHECK_MSG( m_open, FALSE, _T("clipboard not open") );
 434
 435     wxCHECK_MSG( data, FALSE, _T("data is invalid") );
 436
 437     /* if clipboard has been cleared before, create new data broker */
 438
 439     if (!m_dataBroker) m_dataBroker = new wxDataBroker();
 440
 441     /* add new data to list of offered data objects */
 442
 443     m_dataBroker->Add( data );
 444
 445     /* get native format id of new data object */
 446
 447     GdkAtom format = data->GetFormat().GetAtom();
 448
 449     wxCHECK_MSG( format, FALSE, _T("data has invalid format") );
 450
 451     /* This should happen automatically, but to be on the safe side */
 452
 453     m_ownsClipboard = FALSE;
 454     m_ownsPrimarySelection = FALSE;
 455
 456     /* Add handlers if someone requests data */
 457
 458
 459 #if (GTK_MINOR_VERSION > 0)
 460
 461     gtk_selection_add_target( GTK_WIDGET(m_clipboardWidget),
 462                               GDK_SELECTION_PRIMARY,
 463                               format,
 464                               0 );  /* what is info ? */
 465
 466     gtk_selection_add_target( GTK_WIDGET(m_clipboardWidget),
 467                               g_clipboardAtom,
 468                               format,
 469                               0 );  /* what is info ? */
 470
 471     gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
 472                         "selection_get",
 473                         GTK_SIGNAL_FUNC(selection_handler),
 474                         (gpointer) NULL );
 475
 476 #else
 477
 478     gtk_selection_add_handler( m_clipboardWidget,
 479                                g_clipboardAtom,
 480                                format,
 481                                selection_handler,
 482                                (gpointer) NULL );
 483
 484     gtk_selection_add_handler( m_clipboardWidget,
 485                                GDK_SELECTION_PRIMARY,
 486                                format,
 487                                selection_handler,
 488                                (gpointer) NULL );
 489 #endif
 490
 491     /* Tell the world we offer clipboard data */
 492
 493     if (!gtk_selection_owner_set( m_clipboardWidget,
 494                                   g_clipboardAtom,
 495                                   GDK_CURRENT_TIME ))
 496     {
 497         return FALSE;
 498     }
 499     m_ownsClipboard = TRUE;
 500
 501     if (!gtk_selection_owner_set( m_clipboardWidget,
 502                                   GDK_SELECTION_PRIMARY,
 503                                   GDK_CURRENT_TIME ))
 504     {
 505         return FALSE;
 506     }
 507     m_ownsPrimarySelection = TRUE;
 508
 509     return TRUE;
 510 }
 511
 512 void wxClipboard::Close()
 513 {
 514     wxCHECK_RET( m_open, _T("clipboard not open") );
 515
 516     m_open = FALSE;
 517 }
 518
 519 bool wxClipboard::IsSupported( wxDataFormat format )
 520 {
 521     wxCHECK_MSG( m_open, FALSE, _T("clipboard not open") );
 522
 523     /* store requested format to be asked for by callbacks */
 524
 525     m_targetRequested = format.GetAtom();
 526
 527     wxCHECK_MSG( m_targetRequested, FALSE, _T("invalid clipboard format") );
 528
 529     m_formatSupported = FALSE;
 530
 531     /* perform query. this will set m_formatSupported to
 532        TRUE if m_targetRequested is supported.
 533        alsom we have to wait for the "answer" from the
 534        clipboard owner which is an asynchronous process.
 535        therefore we set m_waiting = TRUE here and wait
 536        until the callback "targets_selection_received"
 537        sets it to FALSE */
 538
 539     m_waiting = TRUE;
 540
 541     gtk_selection_convert( m_targetsWidget,
 542                            g_clipboardAtom,
 543                            g_targetsAtom,
 544                            GDK_CURRENT_TIME );
 545
 546     while (m_waiting) gtk_main_iteration();
 547
 548     if (!m_formatSupported) return FALSE;
 549
 550     return TRUE;
 551 }
 552
 553 bool wxClipboard::GetData( wxDataObject *data )
 554 {
 555     wxCHECK_MSG( m_open, FALSE, _T("clipboard not open") );
 556
 557     /* is data supported by clipboard ? */
 558
 559     if (!IsSupported( data->GetFormat() )) return FALSE;
 560
 561     /* store pointer to data object to be filled up by callbacks */
 562
 563     m_receivedData = data;
 564
 565     /* store requested format to be asked for by callbacks */
 566
 567     m_targetRequested = data->GetFormat().GetAtom();
 568
 569     wxCHECK_MSG( m_targetRequested, FALSE, _T("invalid clipboard format") );
 570
 571     /* start query */
 572
 573     m_formatSupported = FALSE;
 574
 575     /* ask for clipboard contents.  this will set
 576        m_formatSupported to TRUE if m_targetRequested
 577        is supported.
 578        also, we have to wait for the "answer" from the
 579        clipboard owner which is an asynchronous process.
 580        therefore we set m_waiting = TRUE here and wait
 581        until the callback "targets_selection_received"
 582        sets it to FALSE */
 583
 584     m_waiting = TRUE;
 585
 586     gtk_selection_convert( m_clipboardWidget,
 587                            g_clipboardAtom,
 588                            m_targetRequested,
 589                            GDK_CURRENT_TIME );
 590
 591     while (m_waiting) gtk_main_iteration();
 592
 593     /* this is a true error as we checked for the presence of such data before */
 594
 595     wxCHECK_MSG( m_formatSupported, FALSE, _T("error retrieving data from clipboard") );
 596
 597     return TRUE;
 598 }
 599
 600 //-----------------------------------------------------------------------------
 601 // wxClipboardModule
 602 //-----------------------------------------------------------------------------
 603
 604 IMPLEMENT_DYNAMIC_CLASS(wxClipboardModule,wxModule)
 605
 606 bool wxClipboardModule::OnInit()
 607 {
 608     wxTheClipboard = new wxClipboard();
 609
 610     return TRUE;
 611 }
 612
 613 void wxClipboardModule::OnExit()
 614 {
 615     if (wxTheClipboard) delete wxTheClipboard;
 616     wxTheClipboard = (wxClipboard*) NULL;
 617 }
 618
 619 #endif
 620
 621   // wxUSE_CLIPBOARD
 622