gov.nasa.worldwind.util.tree
Class ScrollBar

java.lang.Object
  gov.nasa.worldwind.util.tree.ScrollBar

All Implemented Interfaces:

Renderable

public class ScrollBar
extends Object
implements Renderable

A scrollbar component. The scrollable range is defined by four values: min, max, value, and extent. value is the current position of the scroll bar. extent represents the visible region. The four values must always satisfy this relationship:

   min <= value <= value + extent <= max
 

Nested Class Summary

class	ScrollBar.ScrollControl Control for the scroll arrows and areas of the scroll bar above and below the knob.
class	ScrollBar.ScrollKnob Control for dragging the scroll knob.

Field Summary

protected Insets	arrowInsets Insets used to position the triangle in the scroll arrow box.
protected int	autoScrollDelay Delay in milliseconds between each step in auto-scroll operation is effect.
protected String	autoScrollIncrement The amount and direction that the bar scrolls while auto-scrolling.
protected boolean	autoScrolling Indicates whether an auto-scroll operation is active (such as when the user has clicked and held the mouse on the scroll arrow).
static String	BLOCK_DOWN Scroll increment for one page down.
static String	BLOCK_UP Scroll increment for one page up.
protected Rectangle	bounds Full bounds of the scroll bar.
protected static Insets	DEFAULT_ARROW_INSETS Default insets that position the triangle of the scroll arrow in its box.
protected static int	DEFAULT_AUTO_SCROLL_DELAY Default delay, in milliseconds, between auto scroll steps.
protected static Color	DEFAULT_LINE_COLOR Default color used to draw lines in the scroll bar.
protected static int	DEFAULT_MAX_VALUE Default scroll range maximum value.
protected static int	DEFAULT_MIN_SCROLL_KNOB_SIZE Default minimum size, in pixels, of the scroll knob.
protected static int	DEFAULT_MIN_VALUE Default scroll range minimum value.
protected static double	DEFAULT_OPACITY Default opacity.
protected static Color	DEFAULT_SCROLL_KNOB_COLOR1 Default first color in the scroll knob gradient.
protected static Color	DEFAULT_SCROLL_KNOB_COLOR2 Default second color in the scroll knob gradient.
protected static int	DEFAULT_UNIT_INCREMENT Default unit increment.
protected int	extent The amount of the scroll region that is visible in the frame.
protected long	frameNumber Identifies frame used to calculate per-frame values.
protected Color	knobColor1 First color of the gradient used to fill the scroll knob.
protected Color	knobColor2 Second color of the gradient used to fill the scroll knob.
protected Color	lineColor Color applied to lines in the scroll bar.
protected int	maxValue Maximum value in the scroll range.
protected int	minScrollKnobSize The minimum size of the scroll knob.
protected int	minValue Minimum value in the scroll range.
protected long	nextAutoScroll Time at which the scrollbar should automatically update itself.
protected double	opacity Opacity of the scroll bar knob.
protected String	orientation Scroll bar orientation, either AVKey.HORIZONTAL or AVKey.VERTICAL.
protected PickSupport	pickSupport Support for setting up and restoring picking state, and resolving the picked object.
protected int	scrollArrowSize Size, in pixels, of the scroll arrow square.
protected Rectangle	scrollBounds Bounds of the scroll track part of the scroll bar.
protected Rectangle	scrollDownBarBounds Bounds of the scroll bar area below the knob.
protected HotSpot	scrollDownBlockControl HotSpot to handle input on page down control.
protected HotSpot	scrollDownControl HotSpot to handle input on the scroll down control.
protected Rectangle	scrollDownControlBounds Bounds of the "down arrow" control.
protected Rectangle	scrollKnobBounds Bounds of the scroll knob.
protected ScrollBar.ScrollKnob	scrollKnobControl HotSpot to handle input on the scroll knob.
protected Rectangle	scrollUpBarBounds Bounds of the scroll bar area above the knob.
protected HotSpot	scrollUpBlockControl HotSpot to handle input on page up control.
protected HotSpot	scrollUpControl HotSpot to handle input on the scroll up control.
protected Rectangle	scrollUpControlBounds Bounds of the "up arrow" control.
static String	UNIT_DOWN Scroll increment for one unit down.
static String	UNIT_UP Scroll increment for one unit up.
protected int	unitIncrement Amount that the scroll bar scrolls when the up or down arrow is clicked.
protected int	value Current scroll bar value.

Constructor Summary

ScrollBar(HotSpot parent)
Create a scroll bar in the vertical orientation.

ScrollBar(HotSpot parent, String orientation)
Create a scroll bar with an orientation.

Method Summary

protected boolean	canDrawInBounds() Determines if the scrollbar is able to draw within its bounds.
protected void	computeBounds() Compute the bounds of the scroll bar.
protected void	doPick(DrawContext dc) Pick the scroll bar.
protected void	draw(DrawContext dc) Draw the scroll bar.
protected void	drawPickableQuad(DrawContext dc, Object pickObject, Rectangle bounds) Draw a filled quad in a unique pick color.
protected void	drawQuad(DrawContext dc, Rectangle bounds) Draw the vertices of a quadrilateral.
protected void	drawTriangle(DrawContext dc, float rotation, Rectangle bounds, Insets insets) Draw a triangle for one of the scroll bar controls.
int	getAutoScrollDelay() Indicates how frequently the scrollbar updates while one of the scroll arrows is pressed.
int	getBlockIncrement() Get the block increment.
Rectangle	getBounds() Get the bounds of the scroll bar.
int	getExtent() Get the extent.
Color[]	getKnobColor() Get the color of scroll knob.
protected int	getKnobSize(int scrollAreaSize) Get the size of the scroll knob, in pixels.
Color	getLineColor() Get the color used to draw the lines of the scroll bar boundary and the scroll arrows.
int	getMaxValue() Get the maximum value in the scroll range.
int	getMinScrollKnobSize() Indicates the minimum size of the scrollbar knob, in pixels.
int	getMinValue() Get the minimum value in the scroll range.
double	getOpacity() Indicates the opacity of the scroll knob.
String	getOrientation() Get the scroll bar orientation.
protected int	getScrollArrowSize() Get the height of the scroll arrow controls at the top and bottom of the scroll bar.
int	getUnitIncrement() Get the unit increment.
int	getValue() Get the current value of the scroll bar.
double	getValueAsPercentage() Get the value as a percentage of the scroll range.
protected void	initializeUIControls(HotSpot parent) Initialize the objects that represent the UI controls.
boolean	isAutoScrolling() Is the scroll bar auto-scrolling?
void	render(DrawContext dc) Draw the scroll bar.
void	scroll(int amount) Adjust the scroll value.
void	scroll(String amount) Adjust the scroll bar by the unit amount or the block amount.
void	setAutoScrollDelay(int delay) Specifies how often the scrollbar will update itself when one of the scroll arrows is pressed.
void	setBounds(Rectangle bounds) Set the bounds of the scroll bar.
void	setExtent(int extent) Set the extent.
void	setKnobColor(Color color1, Color color2) Set the color of scroll knob.
void	setLineColor(Color color) Set the color of the lines of the scroll bar boundary.
void	setMaxValue(int maxValue) Set the maximum value in the scroll range.
void	setMinScrollKnobSize(int minSize) Specifies the minimum size of the scrollbar knob, in pixels.
void	setMinValue(int minValue) Set the minimum value in the scroll range.
void	setOpacity(double opacity) Specifies the opacity of the scroll knob.
void	setOrientation(String orientation) Set the scroll bar orientation.
void	setUnitIncrement(int unitIncrement) Set the unit increment.
void	setValue(int value) Set the value of the scroll bar.
void	startAutoScroll(String increment) Start an auto-scroll operation.
void	stopAutoScroll() Stop an auto-scroll operation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

arrowInsets

protected Insets arrowInsets

Insets used to position the triangle in the scroll arrow box.

autoScrollDelay

protected int autoScrollDelay

Delay in milliseconds between each step in auto-scroll operation is effect. When auto-scrolling the bar will scroll by the autoScrollIncrement every autoScrollDelay milliseconds.

autoScrollIncrement

protected String autoScrollIncrement

The amount and direction that the bar scrolls while auto-scrolling. One of UNIT_UP, UNIT_DOWN, BLOCK_UP, BLOCK_DOWN.

autoScrolling

protected boolean autoScrolling

Indicates whether an auto-scroll operation is active (such as when the user has clicked and held the mouse on the scroll arrow).

BLOCK_DOWN

public static final String BLOCK_DOWN

Scroll increment for one page down.

See Also:

Constant Field Values

BLOCK_UP

public static final String BLOCK_UP

Scroll increment for one page up.

See Also:

Constant Field Values

bounds

protected Rectangle bounds

Full bounds of the scroll bar.

DEFAULT_ARROW_INSETS

protected static final Insets DEFAULT_ARROW_INSETS

Default insets that position the triangle of the scroll arrow in its box.

DEFAULT_AUTO_SCROLL_DELAY

protected static final int DEFAULT_AUTO_SCROLL_DELAY

Default delay, in milliseconds, between auto scroll steps.

See Also:

Constant Field Values

DEFAULT_LINE_COLOR

protected static final Color DEFAULT_LINE_COLOR

Default color used to draw lines in the scroll bar.

DEFAULT_MAX_VALUE

protected static final int DEFAULT_MAX_VALUE

Default scroll range maximum value.

See Also:

Constant Field Values

DEFAULT_MIN_SCROLL_KNOB_SIZE

protected static final int DEFAULT_MIN_SCROLL_KNOB_SIZE

Default minimum size, in pixels, of the scroll knob.

See Also:

Constant Field Values

DEFAULT_MIN_VALUE

protected static final int DEFAULT_MIN_VALUE

Default scroll range minimum value.

See Also:

Constant Field Values

DEFAULT_OPACITY

protected static final double DEFAULT_OPACITY

Default opacity.

See Also:

Constant Field Values

DEFAULT_SCROLL_KNOB_COLOR1

protected static final Color DEFAULT_SCROLL_KNOB_COLOR1

Default first color in the scroll knob gradient.

DEFAULT_SCROLL_KNOB_COLOR2

protected static final Color DEFAULT_SCROLL_KNOB_COLOR2

Default second color in the scroll knob gradient.

DEFAULT_UNIT_INCREMENT

protected static final int DEFAULT_UNIT_INCREMENT

Default unit increment.

See Also:

Constant Field Values

extent

protected int extent

The amount of the scroll region that is visible in the frame.

frameNumber

protected long frameNumber

Identifies frame used to calculate per-frame values.

knobColor1

protected Color knobColor1

First color of the gradient used to fill the scroll knob.

knobColor2

protected Color knobColor2

Second color of the gradient used to fill the scroll knob.

lineColor

protected Color lineColor

Color applied to lines in the scroll bar.

maxValue

protected int maxValue

Maximum value in the scroll range.

minScrollKnobSize

protected int minScrollKnobSize

The minimum size of the scroll knob. The size of the knob will adjust to the scroll extent, but will never get smaller than this size. This prevents the knob from shrinking to a single pixels if the scroll range is very large.

minValue

protected int minValue

Minimum value in the scroll range.

nextAutoScroll

protected long nextAutoScroll

Time at which the scrollbar should automatically update itself.

opacity

protected double opacity

Opacity of the scroll bar knob.

orientation

protected String orientation

Scroll bar orientation, either AVKey.HORIZONTAL or AVKey.VERTICAL.

pickSupport

protected PickSupport pickSupport

Support for setting up and restoring picking state, and resolving the picked object.

scrollArrowSize

protected int scrollArrowSize

Size, in pixels, of the scroll arrow square.

scrollBounds

protected Rectangle scrollBounds

Bounds of the scroll track part of the scroll bar. This is the region in which the scroll knob moves, and excludes the scroll up and down arrows.

scrollDownBarBounds

protected Rectangle scrollDownBarBounds

Bounds of the scroll bar area below the knob.

scrollDownBlockControl

protected HotSpot scrollDownBlockControl

HotSpot to handle input on page down control.

scrollDownControl

protected HotSpot scrollDownControl

HotSpot to handle input on the scroll down control.

scrollDownControlBounds

protected Rectangle scrollDownControlBounds

Bounds of the "down arrow" control.

scrollKnobBounds

protected Rectangle scrollKnobBounds

Bounds of the scroll knob.

scrollKnobControl

protected ScrollBar.ScrollKnob scrollKnobControl

HotSpot to handle input on the scroll knob.

scrollUpBarBounds

protected Rectangle scrollUpBarBounds

Bounds of the scroll bar area above the knob.

scrollUpBlockControl

protected HotSpot scrollUpBlockControl

HotSpot to handle input on page up control.

scrollUpControl

protected HotSpot scrollUpControl

HotSpot to handle input on the scroll up control.

scrollUpControlBounds

protected Rectangle scrollUpControlBounds

Bounds of the "up arrow" control.

UNIT_DOWN

public static final String UNIT_DOWN

Scroll increment for one unit down.

See Also:

Constant Field Values

UNIT_UP

public static final String UNIT_UP

Scroll increment for one unit up.

See Also:

Constant Field Values

unitIncrement

protected int unitIncrement

Amount that the scroll bar scrolls when the up or down arrow is clicked.

value

protected int value

Current scroll bar value.

Constructor Detail

ScrollBar

public ScrollBar(HotSpot parent)

Create a scroll bar in the vertical orientation.

Parameters:

parent - The screen component that contains the scroll bar. Input events that cannot be handled by the scroll bar will be passed to this component. May be null.

ScrollBar

public ScrollBar(HotSpot parent,
                 String orientation)

Create a scroll bar with an orientation.

Parameters:

orientation - Either AVKey.VERTICAL or AVKey.HORIZONTAL.

parent - The screen component that contains the scroll bar. Input events that cannot be handled by the scroll bar will be passed to this component. May be null.

Method Detail

canDrawInBounds

protected boolean canDrawInBounds()

Determines if the scrollbar is able to draw within its bounds.

Returns:

true if the scroll bar is able to draw within the bounds, or false if the bounds are too small to draw without distortion.

computeBounds

protected void computeBounds()

Compute the bounds of the scroll bar.

doPick

protected void doPick(DrawContext dc)

Pick the scroll bar.

Parameters:

dc - Current draw context.

draw

protected void draw(DrawContext dc)

Draw the scroll bar.

Parameters:

dc - Current draw context.

drawPickableQuad

protected void drawPickableQuad(DrawContext dc,
                                Object pickObject,
                                Rectangle bounds)

Draw a filled quad in a unique pick color. This method must be called between glBegin(GL.GL_QUADS) and glEnd().

Parameters:

dc - Current draw context.

pickObject - User object to attach to the picked object.

bounds - Bounds of the quad.

drawQuad

protected void drawQuad(DrawContext dc,
                        Rectangle bounds)

Draw the vertices of a quadrilateral. This method must be called between glBegin(GL.GL_QUADS) and glEnd().

Parameters:

dc - Current draw context.

bounds - Bounds of the quad.

drawTriangle

protected void drawTriangle(DrawContext dc,
                            float rotation,
                            Rectangle bounds,
                            Insets insets)

Draw a triangle for one of the scroll bar controls.

Parameters:

dc - Draw context.

rotation - Rotation to apply to the triangle. 0 rotation produces a triangle pointing to the right. Rotation must be one of: 0, 90, -90, or 180.

bounds - The bounds of the scroll control. The arrow must be drawn within this rectangle.

insets - Insets to apply to the bounds.

getAutoScrollDelay

public int getAutoScrollDelay()

Indicates how frequently the scrollbar updates while one of the scroll arrows is pressed.

Returns:

The delay, in milliseconds, between scrollbar updates.

getBlockIncrement

public int getBlockIncrement()

Get the block increment. This is the amount that the scroll bar scrolls by when the bar is clicked above or below the knob.

Returns:

The block increment. This implementation returns the extent, so the scroll bar will adjust by a full visible page.

getBounds

public Rectangle getBounds()

Get the bounds of the scroll bar.

Returns:

Scroll bar bounds.

getExtent

public int getExtent()

Get the extent. The extent the amount of the scrollable region that is visible.

Returns:

The extent.

See Also:

setExtent(int)

getKnobColor

public Color[] getKnobColor()

Get the color of scroll knob. The knob is drawn with a gradient made up of two colors.

Returns:

Two element array containing the two colors that form the gradient.

See Also:

setKnobColor(java.awt.Color, java.awt.Color), getLineColor()

getKnobSize

protected int getKnobSize(int scrollAreaSize)

Get the size of the scroll knob, in pixels.

Parameters:

scrollAreaSize - The size of the scroll area, in pixels.

Returns:

Size of the scroll knob, in pixels.

getLineColor

public Color getLineColor()

Get the color used to draw the lines of the scroll bar boundary and the scroll arrows.

Returns:

Color used for the scroll bar lines.

See Also:

setLineColor(java.awt.Color), getKnobColor()

getMaxValue

public int getMaxValue()

Get the maximum value in the scroll range.

Returns:

Maximum value.

See Also:

getMinValue(), setMaxValue(int)

getMinScrollKnobSize

public int getMinScrollKnobSize()

Indicates the minimum size of the scrollbar knob, in pixels.

Returns:

Minimum size of the knob in pixels.

getMinValue

public int getMinValue()

Get the minimum value in the scroll range.

Returns:

Minimum value.

getOpacity

public double getOpacity()

Indicates the opacity of the scroll knob.

Returns:

Scroll knob opacity.

getOrientation

public String getOrientation()

Get the scroll bar orientation.

Returns:

The scroll bar orientation, either AVKey.VERTICAL or AVKey.HORIZONTAL.

getScrollArrowSize

protected int getScrollArrowSize()

Get the height of the scroll arrow controls at the top and bottom of the scroll bar.

Returns:

Height of arrow control, in pixels.

getUnitIncrement

public int getUnitIncrement()

Get the unit increment. This is the amount that the scroll bar scrolls by when one of the arrow controls is clicked.

Returns:

Unit increment.

See Also:

setUnitIncrement(int)

getValue

public int getValue()

Get the current value of the scroll bar.

Returns:

Current value. The value is clamped to the range [minValue : maxValue - extent].

getValueAsPercentage

public double getValueAsPercentage()

Get the value as a percentage of the scroll range.

Returns:

Current value as percentage.

initializeUIControls

protected void initializeUIControls(HotSpot parent)

Initialize the objects that represent the UI controls.

Parameters:

parent - The screen component that contains the scroll bar. Input events that cannot be handled by the scroll bar will be passed to this component. May be null.

isAutoScrolling

public boolean isAutoScrolling()

Is the scroll bar auto-scrolling?

Returns:

True if an auto-scroll operation is in progress.

See Also:

startAutoScroll(String), stopAutoScroll()

render

public void render(DrawContext dc)

Draw the scroll bar. The scroll will not draw its bounds are too small to draw without distortion.

Specified by:

render in interface Renderable

Parameters:

dc - the DrawContext to be used

See Also:

DrawContext

scroll

public void scroll(int amount)

Adjust the scroll value.

Parameters:

amount - Amount to add to the current value. A positive value indicates a scroll down; a negative value indicates a scroll up.

scroll

public void scroll(String amount)

Adjust the scroll bar by the unit amount or the block amount.

Parameters:

amount - One of UNIT_UP, UNIT_DOWN, BLOCK_UP, or BLOCK_DOWN.

setAutoScrollDelay

public void setAutoScrollDelay(int delay)

Specifies how often the scrollbar will update itself when one of the scroll arrows is pressed.

Parameters:

delay - Delay in milliseconds between scrollbar updates. A smaller number makes the scrollbar scroll faster, a larger number makes it scroll slower. The delay may not be negative.

setBounds

public void setBounds(Rectangle bounds)

Set the bounds of the scroll bar.

Parameters:

bounds - New bounds.

setExtent

public void setExtent(int extent)

Set the extent. The extent the amount of the scrollable region that is visible. This method may change the value of the scroll bar to maintain the relationship:

   min <= value <= value + extent <= max
 

Parameters:

extent - New extent. If extent is greater than the range of the scroll bar (max - min), then the extent will be set to the maximum valid value.

See Also:

getExtent()

setKnobColor

public void setKnobColor(Color color1,
                         Color color2)

Set the color of scroll knob. The knob is drawn with a gradient made up of two colors.

Parameters:

color1 - First color in the gradient.

color2 - Second color in the gradient.

See Also:

getKnobColor(), setLineColor(java.awt.Color)

setLineColor

public void setLineColor(Color color)

Set the color of the lines of the scroll bar boundary. This color is also used for the arrows in the scroll controls.

Parameters:

color - Color for lines and scroll arrows.

See Also:

getLineColor(), setKnobColor(java.awt.Color, java.awt.Color)

setMaxValue

public void setMaxValue(int maxValue)

Set the maximum value in the scroll range.

Parameters:

maxValue - New maximum.

setMinScrollKnobSize

public void setMinScrollKnobSize(int minSize)

Specifies the minimum size of the scrollbar knob, in pixels.

Parameters:

minSize - Minimum size of the knob in pixels.

setMinValue

public void setMinValue(int minValue)

Set the minimum value in the scroll range.

Parameters:

minValue - New minimum.

setOpacity

public void setOpacity(double opacity)

Specifies the opacity of the scroll knob.

Parameters:

opacity - New opacity.

setOrientation

public void setOrientation(String orientation)

Set the scroll bar orientation.

Parameters:

orientation - The scroll bar orientation, either AVKey.VERTICAL or AVKey.HORIZONTAL.

setUnitIncrement

public void setUnitIncrement(int unitIncrement)

Set the unit increment.

Parameters:

unitIncrement - New unit increment. Must be a positive number.

See Also:

getUnitIncrement()

setValue

public void setValue(int value)

Set the value of the scroll bar. The value is clamped to the range [minValue : maxValue - extent].

Parameters:

value - New value.

startAutoScroll

public void startAutoScroll(String increment)

Start an auto-scroll operation. During auto-scroll, the scroll bar will adjust its value and repaint continuously until the auto-scroll is stopped.

Parameters:

increment - Amount to adjust scroll bar each time. One of UNIT_UP, UNIT_DOWN, BLOCK_UP, or BLOCK_DOWN.

See Also:

stopAutoScroll(), isAutoScrolling(), scroll(String)

stopAutoScroll

public void stopAutoScroll()

Stop an auto-scroll operation.

See Also:

startAutoScroll(String), isAutoScrolling()