org.bounce
Class FormLayout

java.lang.Object
  org.bounce.FormLayout

All Implemented Interfaces:

java.awt.LayoutManager, java.awt.LayoutManager2

public class FormLayout
extends java.lang.Object
implements java.awt.LayoutManager2

A Layout manager that can be used to layout 2 columns of components. The alignment and fill type of the columns can be set by using the FormConstraint class.
A couple of predefined FormConstraint objects have been defined:

• LEFT, Places the component in the left column of the form.
• RIGHT, Places the component in the right column of the form.
• RIGHT_FILL, Places the component in the right column of the form and fills the component so it takes up the maximum horizontal space.
• FULL, The component takes up both the left and right column, and is aligned to the left of the row.
• FULL_FILL, The component takes up both the left and right column, and is set to fill the whole width of the row.

Notes:
- Alignment of components that fill the height or width completely already will not result in a visible change. Ie. the full positioned component will never react to a Vertical alignment setting.
- The fill method will only change the horizontal appearance.
- Components that are bigger than the available width/height will be LEFT aligned.

Version:

$Revision: 1.5 $, $Date: 2008/01/28 21:28:37 $

Author:

Edwin Dankert

Field Summary

static FormConstraints	FULL A constraint that allows the component to use the total width of the form.
static FormConstraints	FULL_FILL A constraint that allows the component to use the total width of the form and resizes the component to fill the whole width.
static FormConstraints	LEFT A constraint that adds the component to the left side of the form.
static FormConstraints	RIGHT A constraint that adds the component to the right side of the form.
static FormConstraints	RIGHT_FILL A constraint that adds the component to the right side of the form and resizes the component to fill the whole available width.

Constructor Summary

FormLayout()
Constructs a default FormLayout without any horizontal or vertical gaps.

FormLayout(int hGap, int vGap)
Constructs a FormLayout with the specified horizontal and vertical gap.

Method Summary

void	addLayoutComponent(java.awt.Component component, java.lang.Object constraints) Adds the specified component to the layout, using the specified constraint object.
void	addLayoutComponent(java.lang.String name, java.awt.Component comp) Not used, components cannot be added without a constraint.
int	getHgap() Returns the horizontal gap between the left column and the right column.
float	getLayoutAlignmentX(java.awt.Container target) Returns the alignment along the x axis.
float	getLayoutAlignmentY(java.awt.Container target) Returns the alignment along the y axis.
int	getVgap() Returns the vertical gap between the rows.
void	invalidateLayout(java.awt.Container target) Invalidates the layout, indicating that if the layout manager has cached information it should be discarded.
void	layoutContainer(java.awt.Container parent) Lays out the components on the specified container.
java.awt.Dimension	maximumLayoutSize(java.awt.Container target) Returns the maximum size of this component.
java.awt.Dimension	minimumLayoutSize(java.awt.Container parent) Calculates the minimum size dimensions for the specified panel given the components in the specified parent container.
java.awt.Dimension	preferredLayoutSize(java.awt.Container parent) Calculates the preferred size dimensions for the specified container given the components in the specified parent container.
void	removeLayoutComponent(java.awt.Component component) Removes the specified component and constraints from the layout.
void	setConstraints(java.awt.Component component, java.lang.Object constraint) Adds the specified component to the layout, using the specified constraint object.
void	setHgap(int hGap) Sets the horizontal gap between the left column and the right column.
void	setVgap(int vGap) Returns the vertical gap between the rows.

Methods inherited from class java.lang.Object

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

Field Detail

LEFT

public static final FormConstraints LEFT

A constraint that adds the component to the left side of the form.

RIGHT

public static final FormConstraints RIGHT

A constraint that adds the component to the right side of the form.

RIGHT_FILL

public static final FormConstraints RIGHT_FILL

A constraint that adds the component to the right side of the form and resizes the component to fill the whole available width.

FULL

public static final FormConstraints FULL

A constraint that allows the component to use the total width of the form.

FULL_FILL

public static final FormConstraints FULL_FILL

A constraint that allows the component to use the total width of the form and resizes the component to fill the whole width.

Constructor Detail

FormLayout

public FormLayout()

Constructs a default FormLayout without any horizontal or vertical gaps.

FormLayout

public FormLayout(int hGap,
                  int vGap)

Constructs a FormLayout with the specified horizontal and vertical gap.

Parameters:

hGap - the horizontal gap between the left and right components.

vGap - the vertical gap between the rows.

Method Detail

getHgap

public int getHgap()

Returns the horizontal gap between the left column and the right column.

Returns:

the horizontal gap.

setHgap

public void setHgap(int hGap)

Sets the horizontal gap between the left column and the right column.

Parameters:

hGap - the horizontal gap between the columns

getVgap

public int getVgap()

Returns the vertical gap between the rows.

Returns:

the vertical gap.

setVgap

public void setVgap(int vGap)

Returns the vertical gap between the rows.

Parameters:

vGap - the vertical gap between the rows

setConstraints

public void setConstraints(java.awt.Component component,
                           java.lang.Object constraint)

Adds the specified component to the layout, using the specified constraint object. For Form layouts, the constraint must be an instance of the FormConstraints class.

Parameters:

component - the component added to the parent container.

constraint - the constraint for the added component.

removeLayoutComponent

public void removeLayoutComponent(java.awt.Component component)

Removes the specified component and constraints from the layout.

Specified by:

removeLayoutComponent in interface java.awt.LayoutManager

Parameters:

component - the component to be removed

preferredLayoutSize

public java.awt.Dimension preferredLayoutSize(java.awt.Container parent)

Calculates the preferred size dimensions for the specified container given the components in the specified parent container.

Specified by:

preferredLayoutSize in interface java.awt.LayoutManager

Parameters:

parent - the component to be laid out.

Returns:

the preferred size of the layout.

minimumLayoutSize

public java.awt.Dimension minimumLayoutSize(java.awt.Container parent)

Calculates the minimum size dimensions for the specified panel given the components in the specified parent container.

Specified by:

minimumLayoutSize in interface java.awt.LayoutManager

Parameters:

parent - the component to be laid out

Returns:

the minimum size of the layout.

layoutContainer

public void layoutContainer(java.awt.Container parent)

Lays out the components on the specified container.

Specified by:

layoutContainer in interface java.awt.LayoutManager

Parameters:

parent - the component which needs to be laid out

addLayoutComponent

public void addLayoutComponent(java.awt.Component component,
                               java.lang.Object constraints)

Adds the specified component to the layout, using the specified constraint object.

Specified by:

addLayoutComponent in interface java.awt.LayoutManager2

Parameters:

component - the component to be added

constraints - where/how the component is added to the layout.

maximumLayoutSize

public java.awt.Dimension maximumLayoutSize(java.awt.Container target)

Returns the maximum size of this component.

Specified by:

maximumLayoutSize in interface java.awt.LayoutManager2

Parameters:

target - the component to be laid out

Returns:

the maximum size of the layout.

See Also:

Component.getMinimumSize(), Component.getPreferredSize()

getLayoutAlignmentX

public float getLayoutAlignmentX(java.awt.Container target)

Returns the alignment along the x axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

Specified by:

getLayoutAlignmentX in interface java.awt.LayoutManager2

Parameters:

target - the container to calculate X alignment for.

Returns:

the X alignment.

getLayoutAlignmentY

public float getLayoutAlignmentY(java.awt.Container target)

Returns the alignment along the y axis. This specifies how the component would like to be aligned relative to other components. The value should be a number between 0 and 1 where 0 represents alignment along the origin, 1 is aligned the furthest away from the origin, 0.5 is centered, etc.

Specified by:

getLayoutAlignmentY in interface java.awt.LayoutManager2

Parameters:

target - the container to calculate Y alignment for.

Returns:

the Y alignment.

invalidateLayout

public void invalidateLayout(java.awt.Container target)

Invalidates the layout, indicating that if the layout manager has cached information it should be discarded.

Specified by:

invalidateLayout in interface java.awt.LayoutManager2

Parameters:

target - the container.

addLayoutComponent

public void addLayoutComponent(java.lang.String name,
                               java.awt.Component comp)

Not used, components cannot be added without a constraint.

Specified by:

addLayoutComponent in interface java.awt.LayoutManager

Parameters:

name - the component name.

comp - the component.