org.arch4j.ui.layout
Class OriginConstraint

java.lang.Object
  |
  +--org.arch4j.ui.layout.OriginConstraint

Direct Known Subclasses:

AlignmentOriginConstraint, FrameConstraint

public class OriginConstraint

extends Object

An OriginConstraint is used with an instance of FractionalLayout to compute a Rectangle relative to a containing Rectangle, given a preferred Rectangle, by computing a relative origin and then adding an offset to it. The extent of the computed rectangle is the preferredRectangle's extent. After that explanation, I think a couple of examples are in order. Please see the documentation of the instance variables for more information.

• new OriginConstraint(0.0, 0, 0.0, 0) will place the upper-left corner of the component at the upper-left corner (0,0) of the container. The component will be its preferred size.
• new OriginConstraint(0.0, 10, 0.5, 0) will place the upper-left corner of the component 10 pixels down from the top of the container, and exactly halfway across the panel horizontally. The component will be its preferred size.

Version:

1.01, 04/18/96

Author:

Eric Lunt (elunt@mcs.net)

See Also:

FractionalLayout, AlignmentOriginConstraint, FrameConstraint

Field Summary

int	left Represents the number of pixels to be added as an offset to the left edge of a component.
double	leftFraction A number between 0.0 and 1.0 which represents the relative fraction (of the container) for the left edge of a component.
int	top Represents the number of pixels to be added as an offset to the top edge of a component.
double	topFraction A number between 0.0 and 1.0 which represents the relative fraction (of the container) for the top edge of a component.

Constructor Summary

OriginConstraint()
Create an instanace of an OriginConstraint.

OriginConstraint(double lf, int l, double tf, int t)
Create an instance of an OriginConstraint given the left fraction, the left offset, the top fraction, and the top offset.

Method Summary

protected int	adjustedLeft(Dimension containerSize) Given a container size, resolve the left edge of a component
Rectangle	adjustedRectangle(Dimension containerSize, Dimension componentSize) Given the size of a container and the component size, return a Rectangle which appropriately bounds the component given this constraint.
protected int	adjustedTop(Dimension containerSize) Given a container size, resolve the top edge of a component
Dimension	containSize(Dimension componentSize) Given the size of a component, return the smallest size container which could contain it given this constraint.

Methods inherited from class java.lang.Object

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

Field Detail

leftFraction

public double leftFraction

A number between 0.0 and 1.0 which represents the relative fraction (of the container) for the left edge of a component.

left

public int left

Represents the number of pixels to be added as an offset to the left edge of a component.

topFraction

public double topFraction

A number between 0.0 and 1.0 which represents the relative fraction (of the container) for the top edge of a component.

top

public int top

Represents the number of pixels to be added as an offset to the top edge of a component.

Constructor Detail

OriginConstraint

public OriginConstraint()

Create an instanace of an OriginConstraint. This will place the component at the upper-left of the container.

OriginConstraint

public OriginConstraint(double lf,
                        int l,
                        double tf,
                        int t)

Create an instance of an OriginConstraint given the left fraction, the left offset, the top fraction, and the top offset.

Parameters:

lf - the left fraction

l - the left offset

tf - the top fraction

t - the top offset

Method Detail

adjustedLeft

protected int adjustedLeft(Dimension containerSize)

Given a container size, resolve the left edge of a component

Parameters:

containerSize - the size of the container

Returns:

the pixel position of the left edge of the component

adjustedRectangle

public Rectangle adjustedRectangle(Dimension containerSize,
                                   Dimension componentSize)

Given the size of a container and the component size, return a Rectangle which appropriately bounds the component given this constraint.

Parameters:

containerSize - the size of the container

componentSize - the size of the component

Returns:

the containing rectangle

adjustedTop

protected int adjustedTop(Dimension containerSize)

Given a container size, resolve the top edge of a component

Parameters:

containerSize - the size of the container

Returns:

the pixel position of the top edge of the component

containSize

public Dimension containSize(Dimension componentSize)

Given the size of a component, return the smallest size container which could contain it given this constraint.

Parameters:

componentSize - the size of a component

Returns:

the minimum size of a container to satisfy this contraint