[Previous] [Up] [Next]

NSSlider

Authors

Richard Frith-Macdonald
James Dessart

Version: 0.2.1

Date: 8 April, 2000

NSSlider

NSSlider

Declared in: Gui/NSSlider.h

Inherits from: NSControl

Conforms to: NSCoding


An NSSlider displays, and allows control of, some value in the application. It represents a continuous stream of values of type float, which can be retrieved by the method floatValue and set by the method setFloatValue:.

This control is a continuous control. It sends its action message as long as the user is manipulating it. This can be changed by passing NO to the setContinuous: message of a given NSSlider.

Although methods for adding and managing a title are provided, the slider's knob can cover this title, so it is recommended that a label be added near the slider, for identification.

As with many controls, NSSlider relies on its cell counterpart, NSSliderCell. For more information, please see the specification for NSSliderCell.

Use of an NSSlider to do the role of an NSScroller is not recommended. A scroller is intended to represent the visible portion of a view, whereas a slider is intended to represent some value.


acceptsFirstMouse:

- (BOOL) acceptsFirstMouse: (NSEvent*)mouseDownEvent

Returns YES by default. This will allow the first click sent to the slider, when in an inactive window, to both bring the window into focus and manipulate the slider.


allowsTickMarkValuesOnly

- (BOOL) allowsTickMarkValuesOnly

As of yet, unimplemented.


altIncrementValue

- (double) altIncrementValue

Returns the value by which the slider will be incremented if the user holds down the ALT key.


closestTickMarkValueToValue:

- (double) closestTickMarkValueToValue: (double)aValue

As of yet, unimplemented.


image

- (NSImage*) image

Returns the image drawn in the slider's track. Returns nil if this has not been set.


indexOfTickMarkAtPoint:

- (int) indexOfTickMarkAtPoint: (NSPoint)point

As of yet, unimplemented.


isVertical

- (int) isVertical

Returns whether or not the slider is vertical. If, for some reason, this cannot be determined, for such reasons as the slider is not yet displayed, this method returns -1. Generally, a slider is considered vertical if its height is greater than its width.


knobThickness

- (float) knobThickness

Returns the thickness of the slider's knob. This value is in pixels, and is the size of the knob along the slider's track.


maxValue

- (double) maxValue

Returns the maximum value that the slider represents.


minValue

- (double) minValue

Returns the minimum value that the slider represents.


numberOfTickMarks

- (int) numberOfTickMarks

As of yet, unimplemented.


rectOfTickMarkAtIndex:

- (NSRect) rectOfTickMarkAtIndex: (int)index

As of yet, unimplemented.


setAllowsTickMarkValuesOnly:

- (void) setAllowsTickMarkValuesOnly: (BOOL)flag

As of yet, unimplemented.


setAltIncrementValue:

- (void) setAltIncrementValue: (double)increment

Sets the value by which the slider will be incremented, when the ALT key is held down, to increment.


setImage:

- (void) setImage: (NSImage*)barImage

Sets the image to be displayed in the slider's track to barImage.


setKnobThickness:

- (void) setKnobThickness: (float)thickness

Sets the thickness of the knob to thickness, in pixels. This value sets the amount of space which the knob takes up in the slider's track.


setMaxValue:

- (void) setMaxValue: (double)maxValue

Sets the maximum value that the sliders represents to maxValue.


setMinValue:

- (void) setMinValue: (double)minValue

Sets the minimum value that the slider represents to minValue.


setNumberOfTickMarks:

- (void) setNumberOfTickMarks: (int)numberOfTickMarks

As of yet, unimplemented.


setTickMarkPosition:

- (void) setTickMarkPosition: (NSTickMarkPosition)position

As of yet, unimplemented.


setTitle:

- (void) setTitle: (NSString*)barTitle

Sets the title of the slider to barTitle. This title is displayed on the slider's track, behind the knob.


setTitleCell:

- (void) setTitleCell: (NSCell*)titleCell

Sets the cell used to draw the title to titleCell.


setTitleColor:

- (void) setTitleColor: (NSColor*)color

Sets the colour with which the title will be drawn to color.


setTitleFont:

- (void) setTitleFont: (NSFont*)font

Sets the font with which the title will be drawm to font.


tickMarkPosition

- (NSTickMarkPosition) tickMarkPosition

As of yet, unimplemented.


tickMarkValueAtIndex:

- (double) tickMarkValueAtIndex: (int)index

As of yet, unimplemented.


title

- (NSString*) title

Returns the title of the slider as an NSString.


titleCell

- (id) titleCell

Returns the cell used to draw the title.


titleColor

- (NSColor*) titleColor

Returns the colour used to draw the title.


titleFont

- (NSFont*) titleFont

Returns the font used to draw the title.