git.sesse.net Git - vlc/blob - modules/gui/macosx/misc.m

   1 /*****************************************************************************
   2  * misc.m: code not specific to vlc
   3  *****************************************************************************
   4  * Copyright (C) 2003-2007 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Jon Lech Johansen <jon-vl@nanocrew.net>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 #include <Cocoa/Cocoa.h>
  25
  26 #include "intf.h"                                          /* VLCApplication */
  27 #include "misc.h"
  28 #include "playlist.h"
  29 #include "controls.h"
  30
  31 /*****************************************************************************
  32  * NSAnimation (VLCAdditions)
  33  *
  34  *  Missing extension to NSAnimation
  35  *****************************************************************************/
  36
  37 @implementation NSAnimation (VLCAdditions)
  38 /* fake class attributes  */
  39 static NSMapTable *VLCAdditions_userInfo = NULL;
  40
  41 + (void)load
  42 {
  43     /* init our fake object attribute */
  44     VLCAdditions_userInfo = NSCreateMapTable(NSNonRetainedObjectMapKeyCallBacks, NSObjectMapValueCallBacks, 16);
  45 }
  46
  47 - (void)dealloc
  48 {
  49     NSMapRemove(VLCAdditions_userInfo, self);
  50     [super dealloc];
  51 }
  52
  53 - (void)setUserInfo: (void *)userInfo
  54 {
  55     NSMapInsert(VLCAdditions_userInfo, self, (void*)userInfo);
  56 }
  57
  58 - (void *)userInfo
  59 {
  60     return NSMapGet(VLCAdditions_userInfo, self);
  61 }
  62 @end
  63
  64 /*****************************************************************************
  65  * NSScreen (VLCAdditions)
  66  *
  67  *  Missing extension to NSScreen
  68  *****************************************************************************/
  69
  70 @implementation NSScreen (VLCAdditions)
  71
  72 static NSMutableArray *blackoutWindows = NULL;
  73
  74 + (void)load
  75 {
  76     /* init our fake object attribute */
  77     blackoutWindows = [[NSMutableArray alloc] initWithCapacity:1];
  78 }
  79
  80 + (NSScreen *)screenWithDisplayID: (CGDirectDisplayID)displayID
  81 {
  82     int i;
  83
  84     for( i = 0; i < [[NSScreen screens] count]; i++ )
  85     {
  86         NSScreen *screen = [[NSScreen screens] objectAtIndex: i];
  87         if([screen displayID] == displayID)
  88             return screen;
  89     }
  90     return nil;
  91 }
  92
  93 - (CGDirectDisplayID)displayID
  94 {
  95     return (CGDirectDisplayID)_screenNumber;
  96 }
  97
  98 - (void)blackoutOtherScreens
  99 {
 100     unsigned int i;
 101
 102     /* Free our previous blackout window (follow blackoutWindow alloc strategy) */
 103     [blackoutWindows makeObjectsPerformSelector:@selector(close)];
 104     [blackoutWindows removeAllObjects];
 105
 106
 107     for(i = 0; i < [[NSScreen screens] count]; i++)
 108     {
 109         VLCWindow *blackoutWindow;
 110         NSScreen *screen = [[NSScreen screens] objectAtIndex: i];
 111         if(self == screen)
 112             continue;
 113         /* blackoutWindow alloc strategy
 114             - The NSMutableArray blackoutWindows has the blackoutWindow references
 115             - blackoutOtherDisplays is responsible for alloc/releasing its Windows
 116         */
 117         blackoutWindow = [[VLCWindow alloc] initWithContentRect: [screen frame] styleMask: NSBorderlessWindowMask backing:NSBackingStoreBuffered defer:NO];
 118         [blackoutWindow setBackgroundColor:[NSColor blackColor]];
 119         [blackoutWindow setLevel: NSFloatingWindowLevel]; /* Disappear when Expose is triggered */
 120
 121         [blackoutWindow orderFront: self animate: YES];
 122
 123         [blackoutWindows addObject: blackoutWindow];
 124         [blackoutWindow release];
 125     }
 126 }
 127
 128 + (void)unblackoutScreens
 129 {
 130     unsigned int i;
 131
 132     for(i = 0; i < [blackoutWindows count]; i++)
 133     {
 134         VLCWindow *blackoutWindow = [blackoutWindows objectAtIndex: i];
 135         [blackoutWindow closeAndAnimate: YES];
 136     }
 137 }
 138
 139 @end
 140
 141 /*****************************************************************************
 142  * VLCWindow
 143  *
 144  *  Missing extension to NSWindow
 145  *****************************************************************************/
 146
 147 @implementation VLCWindow
 148 - (id)initWithContentRect:(NSRect)contentRect styleMask:(unsigned int)styleMask
 149     backing:(NSBackingStoreType)backingType defer:(BOOL)flag
 150 {
 151     self = [super initWithContentRect:contentRect styleMask:styleMask backing:backingType defer:flag];
 152     if( self )
 153         b_isset_canBecomeKeyWindow = NO;
 154     return self;
 155 }
 156 - (void)setCanBecomeKeyWindow: (BOOL)canBecomeKey
 157 {
 158     b_isset_canBecomeKeyWindow = YES;
 159     b_canBecomeKeyWindow = canBecomeKey;
 160 }
 161
 162 - (BOOL)canBecomeKeyWindow
 163 {
 164     if(b_isset_canBecomeKeyWindow)
 165         return b_canBecomeKeyWindow;
 166
 167     return [super canBecomeKeyWindow];
 168 }
 169
 170 - (void)closeAndAnimate: (BOOL)animate
 171 {
 172     NSInvocation *invoc;
 173
 174     if (!animate || MACOS_VERSION < 10.4f)
 175     {
 176         [super close];
 177         return;
 178     }
 179
 180     invoc = [NSInvocation invocationWithMethodSignature:[super methodSignatureForSelector:@selector(close)]];
 181     [invoc setTarget: (id)super];
 182
 183     if (![self isVisible] || [self alphaValue] == 0.0)
 184     {
 185         [super close];
 186         return;
 187     }
 188
 189     [self orderOut: self animate: YES callback: invoc];
 190 }
 191
 192 - (void)orderOut: (id)sender animate: (BOOL)animate
 193 {
 194     NSInvocation *invoc = [NSInvocation invocationWithMethodSignature:[super methodSignatureForSelector:@selector(orderOut:)]];
 195     [invoc setTarget: (id)super];
 196     [invoc setArgument: sender atIndex: 0];
 197     [self orderOut: sender animate: animate callback: invoc];
 198 }
 199
 200 - (void)orderOut: (id)sender animate: (BOOL)animate callback:(NSInvocation *)callback
 201 {
 202     NSViewAnimation *anim;
 203     NSViewAnimation *current_anim;
 204     NSMutableDictionary *dict;
 205
 206     if (!animate || MACOS_VERSION < 10.4f)
 207     {
 208         [self orderOut: sender];
 209         return;
 210     }
 211
 212     dict = [[NSMutableDictionary alloc] initWithCapacity:2];
 213
 214     [dict setObject:self forKey:NSViewAnimationTargetKey];
 215
 216     [dict setObject:NSViewAnimationFadeOutEffect forKey:NSViewAnimationEffectKey];
 217     anim = [[NSViewAnimation alloc] initWithViewAnimations:[NSArray arrayWithObjects:dict, nil]];
 218     [dict release];
 219
 220     [anim setAnimationBlockingMode:NSAnimationNonblocking];
 221     [anim setDuration:0.9];
 222     [anim setFrameRate:30];
 223     [anim setUserInfo: callback];
 224
 225     @synchronized(self) {
 226         current_anim = self->animation;
 227
 228         if ([[[current_anim viewAnimations] objectAtIndex:0] objectForKey: NSViewAnimationEffectKey] == NSViewAnimationFadeOutEffect && [current_anim isAnimating])
 229         {
 230             [anim release];
 231         }
 232         else
 233         {
 234             if (current_anim)
 235             {
 236                 [current_anim stopAnimation];
 237                 [anim setCurrentProgress:1.0-[current_anim currentProgress]];
 238                 [current_anim release];
 239             }
 240             else
 241                 [anim setCurrentProgress:1.0 - [self alphaValue]];
 242             self->animation = anim;
 243             [self setDelegate: self];
 244             [anim startAnimation];
 245         }
 246     }
 247 }
 248
 249 - (void)orderFront: (id)sender animate: (BOOL)animate
 250 {
 251     NSViewAnimation *anim;
 252     NSViewAnimation *current_anim;
 253     NSMutableDictionary *dict;
 254
 255     if (!animate || MACOS_VERSION < 10.4f)
 256     {
 257         [super orderFront: sender];
 258         [self setAlphaValue: 1.0];
 259         return;
 260     }
 261
 262     if (![self isVisible])
 263     {
 264         [self setAlphaValue: 0.0];
 265         [super orderFront: sender];
 266     }
 267     else if ([self alphaValue] == 1.0)
 268     {
 269         [super orderFront: self];
 270         return;
 271     }
 272
 273     dict = [[NSMutableDictionary alloc] initWithCapacity:2];
 274
 275     [dict setObject:self forKey:NSViewAnimationTargetKey];
 276
 277     [dict setObject:NSViewAnimationFadeInEffect forKey:NSViewAnimationEffectKey];
 278     anim = [[NSViewAnimation alloc] initWithViewAnimations:[NSArray arrayWithObjects:dict, nil]];
 279     [dict release];
 280
 281     [anim setAnimationBlockingMode:NSAnimationNonblocking];
 282     [anim setDuration:0.5];
 283     [anim setFrameRate:30];
 284
 285     @synchronized(self) {
 286         current_anim = self->animation;
 287
 288         if ([[[current_anim viewAnimations] objectAtIndex:0] objectForKey: NSViewAnimationEffectKey] == NSViewAnimationFadeInEffect && [current_anim isAnimating])
 289         {
 290             [anim release];
 291         }
 292         else
 293         {
 294             if (current_anim)
 295             {
 296                 [current_anim stopAnimation];
 297                 [anim setCurrentProgress:1.0 - [current_anim currentProgress]];
 298                 [current_anim release];
 299             }
 300             else
 301                 [anim setCurrentProgress:[self alphaValue]];
 302             self->animation = anim;
 303             [self setDelegate: self];
 304             [self orderFront: sender];
 305             [anim startAnimation];
 306         }
 307     }
 308 }
 309
 310 - (void)animationDidEnd:(NSAnimation*)anim
 311 {
 312     if ([self alphaValue] <= 0.0)
 313     {
 314         NSInvocation * invoc;
 315         [super orderOut: nil];
 316         [self setAlphaValue: 1.0];
 317         if ((invoc = [anim userInfo]))
 318             [invoc invoke];
 319     }
 320 }
 321 @end
 322
 323 /*****************************************************************************
 324  * VLCControllerWindow
 325  *****************************************************************************/
 326
 327 @implementation VLCControllerWindow
 328
 329 - (id)initWithContentRect:(NSRect)contentRect styleMask:(unsigned int)styleMask
 330     backing:(NSBackingStoreType)backingType defer:(BOOL)flag
 331 {
 332     self = [super initWithContentRect:contentRect styleMask:styleMask //& ~NSTitledWindowMask
 333     backing:backingType defer:flag];
 334
 335     [[VLCMain sharedInstance] updateTogglePlaylistState];
 336
 337     return( self );
 338 }
 339
 340 - (BOOL)performKeyEquivalent:(NSEvent *)o_event
 341 {
 342     /* We indeed want to prioritize Cocoa key equivalent against libvlc,
 343        so we perform the menu equivalent now. */
 344     if([[NSApp mainMenu] performKeyEquivalent:o_event])
 345         return TRUE;
 346
 347     return [[VLCMain sharedInstance] hasDefinedShortcutKey:o_event] ||
 348            [(VLCControls *)[[VLCMain sharedInstance] getControls] keyEvent:o_event];
 349 }
 350
 351 @end
 352
 353
 354
 355 /*****************************************************************************
 356  * VLCControllerView
 357  *****************************************************************************/
 358
 359 @implementation VLCControllerView
 360
 361 - (void)dealloc
 362 {
 363     [self unregisterDraggedTypes];
 364     [super dealloc];
 365 }
 366
 367 #if GC_ENABLED
 368 - (void)finalize
 369 {
 370     /* dealloc doesn't get called on 10.5 if GC is enabled, so we need to provide the basic functionality here */
 371     [self unregisterDraggedTypes];
 372     [super finalize];
 373 }
 374 #endif
 375
 376 - (void)awakeFromNib
 377 {
 378     [self registerForDraggedTypes:[NSArray arrayWithObjects:NSTIFFPboardType,
 379         NSFilenamesPboardType, nil]];
 380 }
 381
 382 - (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender
 383 {
 384     if ((NSDragOperationGeneric & [sender draggingSourceOperationMask])
 385                 == NSDragOperationGeneric)
 386     {
 387         return NSDragOperationGeneric;
 388     }
 389     else
 390     {
 391         return NSDragOperationNone;
 392     }
 393 }
 394
 395 - (BOOL)prepareForDragOperation:(id <NSDraggingInfo>)sender
 396 {
 397     return YES;
 398 }
 399
 400 - (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
 401 {
 402     NSPasteboard *o_paste = [sender draggingPasteboard];
 403     NSArray *o_types = [NSArray arrayWithObjects: NSFilenamesPboardType, nil];
 404     NSString *o_desired_type = [o_paste availableTypeFromArray:o_types];
 405     NSData *o_carried_data = [o_paste dataForType:o_desired_type];
 406
 407     if( o_carried_data )
 408     {
 409         if ([o_desired_type isEqualToString:NSFilenamesPboardType])
 410         {
 411             int i;
 412             NSArray *o_array = [NSArray array];
 413             NSArray *o_values = [[o_paste propertyListForType: NSFilenamesPboardType]
 414                         sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)];
 415
 416             for( i = 0; i < (int)[o_values count]; i++)
 417             {
 418                 NSDictionary *o_dic;
 419                 o_dic = [NSDictionary dictionaryWithObject:[o_values objectAtIndex:i] forKey:@"ITEM_URL"];
 420                 o_array = [o_array arrayByAddingObject: o_dic];
 421             }
 422             [(VLCPlaylist *)[[VLCMain sharedInstance] getPlaylist] appendArray: o_array atPos: -1 enqueue:NO];
 423             return YES;
 424         }
 425     }
 426     [self setNeedsDisplay:YES];
 427     return YES;
 428 }
 429
 430 - (void)concludeDragOperation:(id <NSDraggingInfo>)sender
 431 {
 432     [self setNeedsDisplay:YES];
 433 }
 434
 435 @end
 436
 437 /*****************************************************************************
 438  * VLBrushedMetalImageView
 439  *****************************************************************************/
 440
 441 @implementation VLBrushedMetalImageView
 442
 443 - (BOOL)mouseDownCanMoveWindow
 444 {
 445     return YES;
 446 }
 447
 448 - (void)dealloc
 449 {
 450     [self unregisterDraggedTypes];
 451     [super dealloc];
 452 }
 453
 454 #if GC_ENABLED
 455 - (void)finalize
 456 {
 457     /* dealloc doesn't get called on 10.5 if GC is enabled, so we need to provide the basic functionality here */
 458     [self unregisterDraggedTypes];
 459     [super finalize];
 460 }
 461 #endif
 462
 463 - (void)awakeFromNib
 464 {
 465     [self registerForDraggedTypes:[NSArray arrayWithObjects:NSTIFFPboardType,
 466         NSFilenamesPboardType, nil]];
 467 }
 468
 469 - (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender
 470 {
 471     if ((NSDragOperationGeneric & [sender draggingSourceOperationMask])
 472                 == NSDragOperationGeneric)
 473     {
 474         return NSDragOperationGeneric;
 475     }
 476     else
 477     {
 478         return NSDragOperationNone;
 479     }
 480 }
 481
 482 - (BOOL)prepareForDragOperation:(id <NSDraggingInfo>)sender
 483 {
 484     return YES;
 485 }
 486
 487 - (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
 488 {
 489     NSPasteboard *o_paste = [sender draggingPasteboard];
 490     NSArray *o_types = [NSArray arrayWithObjects: NSFilenamesPboardType, nil];
 491     NSString *o_desired_type = [o_paste availableTypeFromArray:o_types];
 492     NSData *o_carried_data = [o_paste dataForType:o_desired_type];
 493     BOOL b_autoplay = config_GetInt( VLCIntf, "macosx-autoplay" );
 494
 495     if( o_carried_data )
 496     {
 497         if ([o_desired_type isEqualToString:NSFilenamesPboardType])
 498         {
 499             int i;
 500             NSArray *o_array = [NSArray array];
 501             NSArray *o_values = [[o_paste propertyListForType: NSFilenamesPboardType]
 502                         sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)];
 503
 504             for( i = 0; i < (int)[o_values count]; i++)
 505             {
 506                 NSDictionary *o_dic;
 507                 o_dic = [NSDictionary dictionaryWithObject:[o_values objectAtIndex:i] forKey:@"ITEM_URL"];
 508                 o_array = [o_array arrayByAddingObject: o_dic];
 509             }
 510             if( b_autoplay )
 511                 [[[VLCMain sharedInstance] getPlaylist] appendArray: o_array atPos: -1 enqueue:NO];
 512             else
 513                 [[[VLCMain sharedInstance] getPlaylist] appendArray: o_array atPos: -1 enqueue:YES];
 514             return YES;
 515         }
 516     }
 517     [self setNeedsDisplay:YES];
 518     return YES;
 519 }
 520
 521 - (void)concludeDragOperation:(id <NSDraggingInfo>)sender
 522 {
 523     [self setNeedsDisplay:YES];
 524 }
 525
 526 @end
 527
 528
 529 /*****************************************************************************
 530  * MPSlider
 531  *****************************************************************************/
 532 @implementation MPSlider
 533
 534 void _drawKnobInRect(NSRect knobRect)
 535 {
 536     // Center knob in given rect
 537     knobRect.origin.x += (int)((float)(knobRect.size.width - 7)/2.0);
 538     knobRect.origin.y += (int)((float)(knobRect.size.height - 7)/2.0);
 539
 540     // Draw diamond
 541     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 3, knobRect.origin.y + 6, 1, 1), NSCompositeSourceOver);
 542     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 2, knobRect.origin.y + 5, 3, 1), NSCompositeSourceOver);
 543     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 1, knobRect.origin.y + 4, 5, 1), NSCompositeSourceOver);
 544     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 0, knobRect.origin.y + 3, 7, 1), NSCompositeSourceOver);
 545     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 1, knobRect.origin.y + 2, 5, 1), NSCompositeSourceOver);
 546     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 2, knobRect.origin.y + 1, 3, 1), NSCompositeSourceOver);
 547     NSRectFillUsingOperation(NSMakeRect(knobRect.origin.x + 3, knobRect.origin.y + 0, 1, 1), NSCompositeSourceOver);
 548 }
 549
 550 void _drawFrameInRect(NSRect frameRect)
 551 {
 552     // Draw frame
 553     NSRectFillUsingOperation(NSMakeRect(frameRect.origin.x, frameRect.origin.y, frameRect.size.width, 1), NSCompositeSourceOver);
 554     NSRectFillUsingOperation(NSMakeRect(frameRect.origin.x, frameRect.origin.y + frameRect.size.height-1, frameRect.size.width, 1), NSCompositeSourceOver);
 555     NSRectFillUsingOperation(NSMakeRect(frameRect.origin.x, frameRect.origin.y, 1, frameRect.size.height), NSCompositeSourceOver);
 556     NSRectFillUsingOperation(NSMakeRect(frameRect.origin.x+frameRect.size.width-1, frameRect.origin.y, 1, frameRect.size.height), NSCompositeSourceOver);
 557 }
 558
 559 - (void)drawRect:(NSRect)rect
 560 {
 561     // Draw default to make sure the slider behaves correctly
 562     [[NSGraphicsContext currentContext] saveGraphicsState];
 563     NSRectClip(NSZeroRect);
 564     [super drawRect:rect];
 565     [[NSGraphicsContext currentContext] restoreGraphicsState];
 566
 567     // Full size
 568     rect = [self bounds];
 569     int diff = (int)(([[self cell] knobThickness] - 7.0)/2.0) - 1;
 570     rect.origin.x += diff-1;
 571     rect.origin.y += diff;
 572     rect.size.width -= 2*diff-2;
 573     rect.size.height -= 2*diff;
 574
 575     // Draw dark
 576     NSRect knobRect = [[self cell] knobRectFlipped:NO];
 577     [[[NSColor blackColor] colorWithAlphaComponent:0.6] set];
 578     _drawFrameInRect(rect);
 579     _drawKnobInRect(knobRect);
 580
 581     // Draw shadow
 582     [[[NSColor blackColor] colorWithAlphaComponent:0.1] set];
 583     rect.origin.x++;
 584     rect.origin.y++;
 585     knobRect.origin.x++;
 586     knobRect.origin.y++;
 587     _drawFrameInRect(rect);
 588     _drawKnobInRect(knobRect);
 589 }
 590
 591 @end
 592
 593
 594 /*****************************************************************************
 595  * ITSlider
 596  *****************************************************************************/
 597
 598 @implementation ITSlider
 599
 600 - (void)awakeFromNib
 601 {
 602     if ([[self cell] class] != [ITSliderCell class]) {
 603         // replace cell
 604         NSSliderCell *oldCell = [self cell];
 605         NSSliderCell *newCell = [[[ITSliderCell alloc] init] autorelease];
 606         [newCell setTag:[oldCell tag]];
 607         [newCell setTarget:[oldCell target]];
 608         [newCell setAction:[oldCell action]];
 609         [newCell setControlSize:[oldCell controlSize]];
 610         [newCell setType:[oldCell type]];
 611         [newCell setState:[oldCell state]];
 612         [newCell setAllowsTickMarkValuesOnly:[oldCell allowsTickMarkValuesOnly]];
 613         [newCell setAltIncrementValue:[oldCell altIncrementValue]];
 614         [newCell setControlTint:[oldCell controlTint]];
 615         [newCell setKnobThickness:[oldCell knobThickness]];
 616         [newCell setMaxValue:[oldCell maxValue]];
 617         [newCell setMinValue:[oldCell minValue]];
 618         [newCell setDoubleValue:[oldCell doubleValue]];
 619         [newCell setNumberOfTickMarks:[oldCell numberOfTickMarks]];
 620         [newCell setEditable:[oldCell isEditable]];
 621         [newCell setEnabled:[oldCell isEnabled]];
 622         [newCell setEntryType:[oldCell entryType]];
 623         [newCell setHighlighted:[oldCell isHighlighted]];
 624         [newCell setTickMarkPosition:[oldCell tickMarkPosition]];
 625         [self setCell:newCell];
 626     }
 627 }
 628
 629 @end
 630
 631 /*****************************************************************************
 632  * ITSliderCell
 633  *****************************************************************************/
 634 @implementation ITSliderCell
 635
 636 - (id)init
 637 {
 638     self = [super init];
 639     _knobOff = [[NSImage imageNamed:@"volumeslider_normal"] retain];
 640     _knobOn = [[NSImage imageNamed:@"volumeslider_blue"] retain];
 641     b_mouse_down = FALSE;
 642     return self;
 643 }
 644
 645 - (void)dealloc
 646 {
 647     [_knobOff release];
 648     [_knobOn release];
 649     [super dealloc];
 650 }
 651
 652 - (void)drawKnob:(NSRect)knob_rect
 653 {
 654     NSImage *knob;
 655
 656     if( b_mouse_down )
 657         knob = _knobOn;
 658     else
 659         knob = _knobOff;
 660
 661     [[self controlView] lockFocus];
 662     [knob compositeToPoint:NSMakePoint( knob_rect.origin.x + 1,
 663         knob_rect.origin.y + knob_rect.size.height -2 )
 664         operation:NSCompositeSourceOver];
 665     [[self controlView] unlockFocus];
 666 }
 667
 668 - (void)stopTracking:(NSPoint)lastPoint at:(NSPoint)stopPoint inView:
 669         (NSView *)controlView mouseIsUp:(BOOL)flag
 670 {
 671     b_mouse_down = NO;
 672     [self drawKnob];
 673     [super stopTracking:lastPoint at:stopPoint inView:controlView mouseIsUp:flag];
 674 }
 675
 676 - (BOOL)startTrackingAt:(NSPoint)startPoint inView:(NSView *)controlView
 677 {
 678     b_mouse_down = YES;
 679     [self drawKnob];
 680     return [super startTrackingAt:startPoint inView:controlView];
 681 }
 682
 683 @end
 684