Preventing default drawing of slider bar in custom NSSlider class
-
Hi
I wrote a custom NSSlider and NSSliderCell, overrode the "drawKnob:"
and "drawBarInside:flipped:" of the NSSliderCell and got the stuff I
want to draw working correctly, but I'm still getting the default
slider bar behind my slider bar. I intentionally don't call the
NSSliderCell's superclass which I thought would do the trick, but no
luck. How can I get rid of the default?
Thanks for any help
Ken
Here's the slider bar draw method
- (void) drawBarInside:(NSRect) inRect
flipped:(BOOL) inFlipped
{
NSRect adjustedRect = NSMakeRect(inRect.origin.x + 10, 0,
inRect.size.width - 20, inRect.size.height);
float rectHeight = inRect.size.height,
leftWidth = [gSliderTrackLeft size].width,
rightWidth = [gSliderTrackRight size].width,
centerWidth = adjustedRect.size.width - leftWidth - rightWidth,
adjustedRight = adjustedRect.origin.x + adjustedRect.size.width,
yOffset = (rectHeight - DefaultSliderBarHeight) / 2;
NSRect leftRect = NSMakeRect(adjustedRect.origin.x,
adjustedRect.origin.y + yOffset, leftWidth, DefaultSliderBarHeight),
rightRect = NSMakeRect(adjustedRight - rightWidth,
adjustedRect.origin.y + yOffset, rightWidth, DefaultSliderBarHeight),
centerRect = NSMakeRect(leftRect.origin.x +
leftRect.size.width, adjustedRect.origin.y + yOffset, centerWidth,
DefaultSliderBarHeight);
minXOrigin = 10;
maxXOrigin = adjustedRight;
[gSliderTrackLeft drawInRect: leftRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[gSliderTrackCenter drawInRect: centerRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[gSliderTrackRight drawInRect: rightRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
} -
Hi Ken
Check out this link for a solution and description of your problem.
http://www.cocoabuilder.com/archive/message/cocoa/2007/1/16/177288
Cheers,
Micke
On Mar 17, 2007, at 9:01 PM, Ken Tozier wrote:
> Hi
>
> I wrote a custom NSSlider and NSSliderCell, overrode the "drawKnob:"
> and "drawBarInside:flipped:" of the NSSliderCell and got the stuff I
> want to draw working correctly, but I'm still getting the default
> slider bar behind my slider bar. I intentionally don't call the
> NSSliderCell's superclass which I thought would do the trick, but
> no luck. How can I get rid of the default?
>
> Thanks for any help
>
> Ken
>
> Here's the slider bar draw method
>
> - (void) drawBarInside:(NSRect) inRect
> flipped:(BOOL) inFlipped
> {
> NSRect adjustedRect = NSMakeRect(inRect.origin.x +
> 10, 0, inRect.size.width - 20, inRect.size.height);
>
> float rectHeight = inRect.size.height,
> leftWidth = [gSliderTrackLeft size].width,
> rightWidth = [gSliderTrackRight size].width,
> centerWidth = adjustedRect.size.width -
> leftWidth - rightWidth,
> adjustedRight = adjustedRect.origin.x +
> adjustedRect.size.width,
> yOffset = (rectHeight -
> DefaultSliderBarHeight) / 2;
>
> NSRect leftRect =
> NSMakeRect(adjustedRect.origin.x, adjustedRect.origin.y + yOffset,
> leftWidth, DefaultSliderBarHeight),
> rightRect = NSMakeRect(adjustedRight -
> rightWidth, adjustedRect.origin.y + yOffset, rightWidth,
> DefaultSliderBarHeight),
> centerRect = NSMakeRect(leftRect.origin.x
> + leftRect.size.width, adjustedRect.origin.y + yOffset, centerWidth,
> DefaultSliderBarHeight);
>
> minXOrigin = 10;
> maxXOrigin = adjustedRight;
>
> [gSliderTrackLeft drawInRect: leftRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [gSliderTrackCenter drawInRect: centerRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [gSliderTrackRight drawInRect: rightRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
> }
-
Thanks Micke that works
It seems really dumb though that Apple doesn't expose "- (BOOL)
_usesCustomTrackImage" It's a very elegant way to override drawing of
the default track bar. The alternative from that link (By Dominik Pich)
- (void) drawWithFrame: (NSRect)cellFrame inView: (NSView*)controlView
{
cellFrame = [self drawingRectForBounds: cellFrame];
[super setTrackRect: cellFrame]; //need to access private member
[self drawBarInside: cellFrame flipped: [controlView isFlipped]];
[self drawKnob];
}
@interface NSSliderCell (SetTrackRect)
@end
@implementation NSSliderCell (SetTrackRect)
- (void) setTrackRect: (NSRect)theRect {
_trackRect = theRect;
}
@end
May work but why force developers to write all that override code
when they could just use "_usesCustomTrackImage"?
I can't think of a single good reason to hide this method. Apple
overrides sliders all the time in their own apps. Why make it such a
headache for everyone else?
/rant
-Ken
On Mar 17, 2007, at 4:16 PM, Mikael Gransell wrote:
> Hi Ken
>
> Check out this link for a solution and description of your problem.
>
> http://www.cocoabuilder.com/archive/message/cocoa/2007/1/16/177288
>
> Cheers,
> Micke
>
>
> On Mar 17, 2007, at 9:01 PM, Ken Tozier wrote:
>
>> Hi
>>
>> I wrote a custom NSSlider and NSSliderCell, overrode the
>> "drawKnob:" and "drawBarInside:flipped:" of the NSSliderCell and
>> got the stuff I want to draw working correctly, but I'm still
>> getting the default slider bar behind my slider bar. I
>> intentionally don't call the NSSliderCell's superclass which I
>> thought would do the trick, but no luck. How can I get rid of the
>> default?
>>
>> Thanks for any help
>>
>> Ken
>>
>> Here's the slider bar draw method
>>
>> - (void) drawBarInside:(NSRect) inRect
>> flipped:(BOOL) inFlipped
>> {
>> NSRect adjustedRect = NSMakeRect(inRect.origin.x
>> + 10, 0, inRect.size.width - 20, inRect.size.height);
>>
>> float rectHeight = inRect.size.height,
>> leftWidth = [gSliderTrackLeft size].width,
>> rightWidth = [gSliderTrackRight
>> size].width,
>> centerWidth = adjustedRect.size.width -
>> leftWidth - rightWidth,
>> adjustedRight = adjustedRect.origin.x +
>> adjustedRect.size.width,
>> yOffset = (rectHeight -
>> DefaultSliderBarHeight) / 2;
>>
>> NSRect leftRect = NSMakeRect
>> (adjustedRect.origin.x, adjustedRect.origin.y + yOffset,
>> leftWidth, DefaultSliderBarHeight),
>> rightRect = NSMakeRect(adjustedRight -
>> rightWidth, adjustedRect.origin.y + yOffset, rightWidth,
>> DefaultSliderBarHeight),
>> centerRect = NSMakeRect
>> (leftRect.origin.x + leftRect.size.width, adjustedRect.origin.y +
>> yOffset, centerWidth, DefaultSliderBarHeight);
>>
>> minXOrigin = 10;
>> maxXOrigin = adjustedRight;
>>
>> [gSliderTrackLeft drawInRect: leftRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [gSliderTrackCenter drawInRect: centerRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [gSliderTrackRight drawInRect: rightRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>> }
>
-
I feel that the main problem here is that the name of that method and
the documentation can easily be misinterpreted since they do their
drawing somewhere else. In other words, the method -
(BOOL)_usesCustomTrackImage should not need to be there.
/Micke
On Mar 17, 2007, at 11:10 PM, Ken Tozier wrote:
> Thanks Micke that works
>
> It seems really dumb though that Apple doesn't expose "-
> (BOOL)_usesCustomTrackImage" It's a very elegant way to override
> drawing of the default track bar. The alternative from that link (By
> Dominik Pich)
>
> - (void) drawWithFrame: (NSRect)cellFrame inView: (NSView*)controlView
> {
> cellFrame = [self drawingRectForBounds: cellFrame];
>
> [super setTrackRect: cellFrame]; //need to access private member
>
> [self drawBarInside: cellFrame flipped: [controlView isFlipped]];
> [self drawKnob];
> }
>
> @interface NSSliderCell (SetTrackRect)
> @end
>
> @implementation NSSliderCell (SetTrackRect)
>
> - (void) setTrackRect: (NSRect)theRect {
> _trackRect = theRect;
> }
>
> @end
>
>
> May work but why force developers to write all that override code
> when they could just use "_usesCustomTrackImage"?
>
> I can't think of a single good reason to hide this method. Apple
> overrides sliders all the time in their own apps. Why make it such a
> headache for everyone else?
> /rant
>
> -Ken
>
>
> On Mar 17, 2007, at 4:16 PM, Mikael Gransell wrote:
>
>> Hi Ken
>>
>> Check out this link for a solution and description of your problem.
>>
>> http://www.cocoabuilder.com/archive/message/cocoa/2007/1/16/177288
>>
>> Cheers,
>> Micke
>>
>>
>> On Mar 17, 2007, at 9:01 PM, Ken Tozier wrote:
>>
>>
>>> Hi
>>
>>>
>>
>>> I wrote a custom NSSlider and NSSliderCell, overrode the
>>> "drawKnob:" and "drawBarInside:flipped:" of the NSSliderCell and
>>> got the stuff I want to draw working correctly, but I'm still
>>> getting the default slider bar behind my slider bar. I
>>> intentionally don't call the NSSliderCell's superclass which I
>>> thought would do the trick, but no luck. How can I get rid of the
>>> default?
>>
>>>
>>
>>> Thanks for any help
>>
>>>
>>
>>> Ken
>>
>>>
>>
>>> Here's the slider bar draw method
>>
>>>
>>
>>> - (void) drawBarInside:(NSRect) inRect
>>
>>> flipped:(BOOL) inFlipped
>>
>>> {
>>
>>> NSRect adjustedRect = NSMakeRect(inRect.origin.x +
>>> 10, 0, inRect.size.width - 20, inRect.size.height);
>>
>>>
>>
>>> float rectHeight = inRect.size.height,
>>
>>> leftWidth = [gSliderTrackLeft size].width,
>>
>>> rightWidth = [gSliderTrackRight
>>> size].width,
>>
>>> centerWidth = adjustedRect.size.width -
>>> leftWidth - rightWidth,
>>
>>> adjustedRight = adjustedRect.origin.x +
>>> adjustedRect.size.width,
>>
>>> yOffset = (rectHeight -
>>> DefaultSliderBarHeight) / 2;
>>
>>>
>>
>>> NSRect leftRect =
>>> NSMakeRect(adjustedRect.origin.x, adjustedRect.origin.y + yOffset,
>>> leftWidth, DefaultSliderBarHeight),
>>
>>> rightRect = NSMakeRect(adjustedRight -
>>> rightWidth, adjustedRect.origin.y + yOffset, rightWidth,
>>> DefaultSliderBarHeight),
>>
>>> centerRect = NSMakeRect(leftRect.origin.x
>>> + leftRect.size.width, adjustedRect.origin.y + yOffset,
>>> centerWidth, DefaultSliderBarHeight);
>>
>>>
>>
>>> minXOrigin = 10;
>>
>>> maxXOrigin = adjustedRight;
>>
>>>
>>
>>> [gSliderTrackLeft drawInRect: leftRect
>>
>>> fromRect: NSZeroRect
>>
>>> operation: NSCompositeSourceOver
>>
>>> fraction: 1.0];
>>
>>>
>>
>>> [gSliderTrackCenter drawInRect: centerRect
>>
>>> fromRect: NSZeroRect
>>
>>> operation: NSCompositeSourceOver
>>
>>> fraction: 1.0];
>>
>>>
>>
>>> [gSliderTrackRight drawInRect: rightRect
>>
>>> fromRect: NSZeroRect
>>
>>> operation: NSCompositeSourceOver
>>
>>> fraction: 1.0];
>>
>>> }
>>
>>>
>>
>>
-
Oy.
After 3 more hours of futzing, I can't get the knob to center on the
slider bar without leaving part of itself behind when it moves.
Anyone see what I'm doing wrong here?
Here's the draw knob method:
- (void) drawKnob:(NSRect) knobRect
{
float adjustedLeft = knobRect.origin.x,
knobWidth = knobRect.size.width,
knobHeight = knobRect.size.height,
maxRight = maxXOrigin - knobWidth;
if ((adjustedLeft) < 10)
adjustedLeft = 10;
else if (adjustedLeft > maxRight)
adjustedLeft = maxRight;
adjustedKnobRect = NSMakeRect(adjustedLeft, knobRect.origin.y,
knobWidth, knobHeight);
// following line centers the knob correctly,
// but when you drag it, half of the pixels are
// left behind
/*if (isFlipped)
adjustedRect.origin.y += 4;*/
[gSliderKnob drawInRect: adjustedKnobRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
}
And here's the other draw stuff in case that sheds light on the problem
- (void) drawBarInside:(NSRect) inRect
flipped:(BOOL) inFlipped
{
// may need this for knob drawing
isFlipped = inFlipped;
// update the rectangles for the slider rail
[self updateGeometryWithFrame: inRect];
// draw control images
[gSliderBackgroundImage drawInRect: inRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[gSliderTrackLeft drawInRect: leftRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[gSliderTrackCenter drawInRect: middleRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[gSliderTrackRight drawInRect: rightRect
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[self drawKnob];
}
- (void) updateGeometryWithFrame:(NSRect) inFrame
{
adjustedSliderRect = NSMakeRect(inFrame.origin.x + 10, 0,
inFrame.size.width - 20, inFrame.size.height);
float rectHeight = inFrame.size.height,
leftWidth = [gSliderTrackLeft size].width,
rightWidth = [gSliderTrackRight size].width,
centerWidth = adjustedSliderRect.size.width - leftWidth -
rightWidth,
yOffset = (rectHeight - DefaultSliderBarHeight) / 2;
adjustedRight = adjustedSliderRect.origin.x +
adjustedSliderRect.size.width;
leftRect = NSMakeRect(adjustedSliderRect.origin.x, yOffset,
leftWidth, DefaultSliderBarHeight);
rightRect = NSMakeRect(adjustedRight - rightWidth, yOffset,
rightWidth, DefaultSliderBarHeight);
middleRect = NSMakeRect(leftRect.origin.x + leftRect.size.width,
yOffset, centerWidth, DefaultSliderBarHeight);
minXOrigin = 10;
maxXOrigin = adjustedRight;
}
- (BOOL)_usesCustomTrackImage
{
return YES;
} -
Where does it leave parts of it behind? One the top and bottom of the
scroller or all over?
On Mar 18, 2007, at 5:03 AM, Ken Tozier wrote:
> Oy.
>
> After 3 more hours of futzing, I can't get the knob to center on the
> slider bar without leaving part of itself behind when it moves.
> Anyone see what I'm doing wrong here?
>
> Here's the draw knob method:
>
> - (void) drawKnob:(NSRect) knobRect
> {
> float adjustedLeft = knobRect.origin.x,
> knobWidth = knobRect.size.width,
> knobHeight = knobRect.size.height,
> maxRight = maxXOrigin - knobWidth;
>
> if ((adjustedLeft) < 10)
> adjustedLeft = 10;
> else if (adjustedLeft > maxRight)
> adjustedLeft = maxRight;
>
> adjustedKnobRect = NSMakeRect(adjustedLeft,
> knobRect.origin.y, knobWidth, knobHeight);
>
> // following line centers the knob correctly,
> // but when you drag it, half of the pixels are
> // left behind
> /*if (isFlipped)
> adjustedRect.origin.y += 4;*/
>
> [gSliderKnob drawInRect: adjustedKnobRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
> }
>
>
> And here's the other draw stuff in case that sheds light on the
> problem
>
> - (void) drawBarInside:(NSRect) inRect
> flipped:(BOOL) inFlipped
> {
> // may need this for knob drawing
> isFlipped = inFlipped;
>
> // update the rectangles for the slider rail
> [self updateGeometryWithFrame: inRect];
>
> // draw control images
> [gSliderBackgroundImage drawInRect: inRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [gSliderTrackLeft drawInRect: leftRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [gSliderTrackCenter drawInRect: middleRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [gSliderTrackRight drawInRect: rightRect
> fromRect: NSZeroRect
> operation: NSCompositeSourceOver
> fraction: 1.0];
>
> [self drawKnob];
> }
>
> - (void) updateGeometryWithFrame:(NSRect) inFrame
> {
> adjustedSliderRect = NSMakeRect(inFrame.origin.x + 10, 0,
> inFrame.size.width - 20, inFrame.size.height);
>
> float rectHeight = inFrame.size.height,
> leftWidth = [gSliderTrackLeft size].width,
> rightWidth = [gSliderTrackRight size].width,
> centerWidth = adjustedSliderRect.size.width -
> leftWidth - rightWidth,
> yOffset = (rectHeight -
> DefaultSliderBarHeight) / 2;
>
> adjustedRight = adjustedSliderRect.origin.x +
> adjustedSliderRect.size.width;
> leftRect = NSMakeRect(adjustedSliderRect.origin.x,
> yOffset, leftWidth, DefaultSliderBarHeight);
> rightRect = NSMakeRect(adjustedRight - rightWidth,
> yOffset, rightWidth, DefaultSliderBarHeight);
> middleRect = NSMakeRect(leftRect.origin.x +
> leftRect.size.width, yOffset, centerWidth, DefaultSliderBarHeight);
>
> minXOrigin = 10;
> maxXOrigin = adjustedRight;
> }
>
> - (BOOL)_usesCustomTrackImage
> {
> return YES;
> }
-
On Mar 18, 2007, at 4:35 AM, Mikael Gransell wrote:
> Where does it leave parts of it behind? One the top and bottom of
> the scroller or all over?
The part that extends below the bottom edge of the slider track.
Approximately the bottom third of the knob. If you resize the view it
refreshes but if you drag the knob again, same deal.
>
>
> On Mar 18, 2007, at 5:03 AM, Ken Tozier wrote:
>
>> Oy.
>>
>> After 3 more hours of futzing, I can't get the knob to center on
>> the slider bar without leaving part of itself behind when it
>> moves. Anyone see what I'm doing wrong here?
>>
>> Here's the draw knob method:
>>
>> - (void) drawKnob:(NSRect) knobRect
>> {
>> float adjustedLeft = knobRect.origin.x,
>> knobWidth = knobRect.size.width,
>> knobHeight = knobRect.size.height,
>> maxRight = maxXOrigin - knobWidth;
>>
>> if ((adjustedLeft) < 10)
>> adjustedLeft = 10;
>> else if (adjustedLeft > maxRight)
>> adjustedLeft = maxRight;
>>
>> adjustedKnobRect = NSMakeRect(adjustedLeft,
>> knobRect.origin.y, knobWidth, knobHeight);
>>
>> // following line centers the knob correctly,
>> // but when you drag it, half of the pixels are
>> // left behind
>> /*if (isFlipped)
>> adjustedRect.origin.y += 4;*/
>>
>> [gSliderKnob drawInRect: adjustedKnobRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>> }
>>
>>
>> And here's the other draw stuff in case that sheds light on the
>> problem
>>
>> - (void) drawBarInside:(NSRect) inRect
>> flipped:(BOOL) inFlipped
>> {
>> // may need this for knob drawing
>> isFlipped = inFlipped;
>>
>> // update the rectangles for the slider rail
>> [self updateGeometryWithFrame: inRect];
>>
>> // draw control images
>> [gSliderBackgroundImage drawInRect: inRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [gSliderTrackLeft drawInRect: leftRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [gSliderTrackCenter drawInRect: middleRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [gSliderTrackRight drawInRect: rightRect
>> fromRect: NSZeroRect
>> operation: NSCompositeSourceOver
>> fraction: 1.0];
>>
>> [self drawKnob];
>> }
>>
>> - (void) updateGeometryWithFrame:(NSRect) inFrame
>> {
>> adjustedSliderRect = NSMakeRect(inFrame.origin.x + 10, 0,
>> inFrame.size.width - 20, inFrame.size.height);
>>
>> float rectHeight = inFrame.size.height,
>> leftWidth = [gSliderTrackLeft size].width,
>> rightWidth = [gSliderTrackRight
>> size].width,
>> centerWidth = adjustedSliderRect.size.width
>> - leftWidth - rightWidth,
>> yOffset = (rectHeight -
>> DefaultSliderBarHeight) / 2;
>>
>> adjustedRight = adjustedSliderRect.origin.x +
>> adjustedSliderRect.size.width;
>> leftRect = NSMakeRect(adjustedSliderRect.origin.x,
>> yOffset, leftWidth, DefaultSliderBarHeight);
>> rightRect = NSMakeRect(adjustedRight - rightWidth,
>> yOffset, rightWidth, DefaultSliderBarHeight);
>> middleRect = NSMakeRect(leftRect.origin.x +
>> leftRect.size.width, yOffset, centerWidth, DefaultSliderBarHeight);
>>
>> minXOrigin = 10;
>> maxXOrigin = adjustedRight;
>> }
>>
>> - (BOOL)_usesCustomTrackImage
>> {
>> return YES;
>> }
-
Don't override the private _usesCustomTrackImage: method. Instead,
override -[NSSliderCell drawWithFrame:inView:] and call your -
drawBarInside:flipped: and -drawKnob: methods inside that. You'll
have to do calculations for framing, positioning, etc., but they're
not hard.
In the end, this may actually solve your problem, as well, because
you'll have full control over what's drawn where. You can redraw
dirty areas as you see fit, or summarily redraw the entire bar at
once if it's not a performance issue.
This is what I do in Think's custom slider, and it works quite well.
--
m-s
On 18 Mar, 2007, at 04:38, Ken Tozier wrote:
>
> On Mar 18, 2007, at 4:35 AM, Mikael Gransell wrote:
>
>> Where does it leave parts of it behind? One the top and bottom of
>> the scroller or all over?
>
> The part that extends below the bottom edge of the slider track.
> Approximately the bottom third of the knob. If you resize the view
> it refreshes but if you drag the knob again, same deal.
>
>>
>>
>> On Mar 18, 2007, at 5:03 AM, Ken Tozier wrote:
>>
>>> Oy.
>>>
>>> After 3 more hours of futzing, I can't get the knob to center on
>>> the slider bar without leaving part of itself behind when it
>>> moves. Anyone see what I'm doing wrong here?
>>>
>>> Here's the draw knob method:
>>>
>>> - (void) drawKnob:(NSRect) knobRect
>>> {
>>> float adjustedLeft = knobRect.origin.x,
>>> knobWidth = knobRect.size.width,
>>> knobHeight = knobRect.size.height,
>>> maxRight = maxXOrigin - knobWidth;
>>>
>>> if ((adjustedLeft) < 10)
>>> adjustedLeft = 10;
>>> else if (adjustedLeft > maxRight)
>>> adjustedLeft = maxRight;
>>>
>>> adjustedKnobRect = NSMakeRect(adjustedLeft,
>>> knobRect.origin.y, knobWidth, knobHeight);
>>>
>>> // following line centers the knob correctly,
>>> // but when you drag it, half of the pixels are
>>> // left behind
>>> /*if (isFlipped)
>>> adjustedRect.origin.y += 4;*/
>>>
>>> [gSliderKnob drawInRect: adjustedKnobRect
>>> fromRect: NSZeroRect
>>> operation: NSCompositeSourceOver
>>> fraction: 1.0];
>>> }
>>>
>>>
>>> And here's the other draw stuff in case that sheds light on the
>>> problem
>>>
>>> - (void) drawBarInside:(NSRect) inRect
>>> flipped:(BOOL) inFlipped
>>> {
>>> // may need this for knob drawing
>>> isFlipped = inFlipped;
>>>
>>> // update the rectangles for the slider rail
>>> [self updateGeometryWithFrame: inRect];
>>>
>>> // draw control images
>>> [gSliderBackgroundImage drawInRect: inRect
>>> fromRect: NSZeroRect
>>> operation: NSCompositeSourceOver
>>> fraction: 1.0];
>>>
>>> [gSliderTrackLeft drawInRect: leftRect
>>> fromRect: NSZeroRect
>>> operation: NSCompositeSourceOver
>>> fraction: 1.0];
>>>
>>> [gSliderTrackCenter drawInRect: middleRect
>>> fromRect: NSZeroRect
>>> operation: NSCompositeSourceOver
>>> fraction: 1.0];
>>>
>>> [gSliderTrackRight drawInRect: rightRect
>>> fromRect: NSZeroRect
>>> operation: NSCompositeSourceOver
>>> fraction: 1.0];
>>>
>>> [self drawKnob];
>>> }
>>>
>>> - (void) updateGeometryWithFrame:(NSRect) inFrame
>>> {
>>> adjustedSliderRect = NSMakeRect(inFrame.origin.x + 10, 0,
>>> inFrame.size.width - 20, inFrame.size.height);
>>>
>>> float rectHeight = inFrame.size.height,
>>> leftWidth = [gSliderTrackLeft size].width,
>>> rightWidth = [gSliderTrackRight
>>> size].width,
>>> centerWidth = adjustedSliderRect.size.width
>>> - leftWidth - rightWidth,
>>> yOffset = (rectHeight -
>>> DefaultSliderBarHeight) / 2;
>>>
>>> adjustedRight = adjustedSliderRect.origin.x +
>>> adjustedSliderRect.size.width;
>>> leftRect = NSMakeRect(adjustedSliderRect.origin.x,
>>> yOffset, leftWidth, DefaultSliderBarHeight);
>>> rightRect = NSMakeRect(adjustedRight - rightWidth,
>>> yOffset, rightWidth, DefaultSliderBarHeight);
>>> middleRect = NSMakeRect(leftRect.origin.x +
>>> leftRect.size.width, yOffset, centerWidth, DefaultSliderBarHeight);
>>>
>>> minXOrigin = 10;
>>> maxXOrigin = adjustedRight;
>>> }
>>>
>>> - (BOOL)_usesCustomTrackImage
>>> {
>>> return YES;
>>> }
-
Sorry, this is an NSCell method, not NSSliderCell specifically. :-)
--
m-s
On 18 Mar, 2007, at 04:59, Michael Watson wrote:
> -[NSSliderCell drawWithFrame:inView:]
