org.eclipse.swt.layout
Class RowLayout

java.lang.Object
  |
  +--org.eclipse.swt.widgets.Layout
        |
        +--org.eclipse.swt.layout.RowLayout

public final class RowLayout

extends Layout

Safe: Instances of this class determine the size and position of the children of a Composite by placing them either in horizontal rows or vertical columns within the parent Composite.

RowLayout aligns all controls in one row if the type is set to horizontal, and one column if it is set to vertical. It has the ability to wrap, and provides configurable margins and spacing. RowLayout has a number of configuration fields. In addition, the height and width of each control in a RowLayout can be specified by setting a RowData object into the control using setLayoutData ().

The following example code creates a RowLayout, sets all of its fields to non-default values, and then sets it into a Shell.

 		RowLayout rowLayout = new RowLayout();
 		rowLayout.wrap = false;
 		rowLayout.pack = false;
 		rowLayout.justify = true;
 		rowLayout.type = SWT.VERTICAL;
 		rowLayout.marginLeft = 5;
 		rowLayout.marginTop = 5;
 		rowLayout.marginRight = 5;
 		rowLayout.marginBottom = 5;
 		rowLayout.spacing = 0;
 		shell.setLayout(rowLayout);
 

If you are using the default field values, you only need one line of code:

 		shell.setLayout(new RowLayout());
 

See Also:

RowData

Field Summary

boolean	justify Enabled: justify specifies whether the controls in a row should be fully justified, with any extra space placed between the controls.
int	marginBottom Enabled: marginBottom specifies the number of pixels of vertical margin that will be placed along the bottom edge of the layout.
int	marginLeft Enabled: marginLeft specifies the number of pixels of horizontal margin that will be placed along the left edge of the layout.
int	marginRight Enabled: marginRight specifies the number of pixels of horizontal margin that will be placed along the right edge of the layout.
int	marginTop Enabled: marginTop specifies the number of pixels of vertical margin that will be placed along the top edge of the layout.
boolean	pack Enabled: pack specifies whether all controls in the layout take their preferred size.
int	spacing Enabled: spacing specifies the number of pixels between the edge of one cell and the edge of its neighbouring cell.
int	type Enabled: type specifies whether the layout places controls in rows or columns.
boolean	wrap Enabled: wrap specifies whether a control will be wrapped to the next row if there is insufficient space on the current row.

Constructor Summary

RowLayout()
Enabled: Constructs a new instance of this class.

RowLayout(int type)
Enabled: Constructs a new instance of this class given the type.

Method Summary

protected Point	computeSize(Composite composite, int wHint, int hHint, boolean flushCache) Computes and returns the size of the specified composite's client area according to this layout.
(package private) Point	getSize(Control control, boolean flushCache)
protected void	layout(Composite composite, boolean flushCache) Lays out the children of the specified composite according to this layout.
(package private) Point	layoutHorizontal(Composite composite, boolean move, boolean wrap, int width, boolean flushCache)
(package private) Point	layoutVertical(Composite composite, boolean move, boolean wrap, int height, boolean flushCache)

Methods inherited from class java.lang.Object

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

Field Detail

type

public int type

Enabled: type specifies whether the layout places controls in rows or columns. The default value is HORIZONTAL. Possible values are: HORIZONTAL: Position the controls horizontally from left to right VERTICAL: Position the controls vertically from top to bottom

Since:

2.0

wrap

public boolean wrap

Enabled: wrap specifies whether a control will be wrapped to the next row if there is insufficient space on the current row. The default value is true.

pack

public boolean pack

Enabled: pack specifies whether all controls in the layout take their preferred size. If pack is false, all controls will have the same size which is the size required to accommodate the largest preferred height and the largest preferred width of all the controls in the layout. The default value is true.

justify

public boolean justify

Enabled: justify specifies whether the controls in a row should be fully justified, with any extra space placed between the controls. The default value is false.

spacing

public int spacing

Enabled: spacing specifies the number of pixels between the edge of one cell and the edge of its neighbouring cell. The default value is 3.

marginLeft

public int marginLeft

Enabled: marginLeft specifies the number of pixels of horizontal margin that will be placed along the left edge of the layout. The default value is 3.

marginTop

public int marginTop

Enabled: marginTop specifies the number of pixels of vertical margin that will be placed along the top edge of the layout. The default value is 3.

marginRight

public int marginRight

Enabled: marginRight specifies the number of pixels of horizontal margin that will be placed along the right edge of the layout. The default value is 3.

marginBottom

public int marginBottom

Enabled: marginBottom specifies the number of pixels of vertical margin that will be placed along the bottom edge of the layout. The default value is 3.

Constructor Detail

RowLayout

public RowLayout()

Enabled: Constructs a new instance of this class.

RowLayout

public RowLayout(int type)

Enabled: Constructs a new instance of this class given the type.

Parameters:

type - the type of row layout

Since:

2.0

Method Detail

computeSize

protected Point computeSize(Composite composite,
                            int wHint,
                            int hHint,
                            boolean flushCache)

Description copied from class: Layout

Computes and returns the size of the specified composite's client area according to this layout.

This method computes the minimum size that the client area of the composite must be in order to position all children at their minimum size inside the composite according to the layout algorithm encoded by this layout.

When a width or height hint is supplied, it is used to constrain the result. For example, if a width hint is provided that is less than the minimum width of the client area, the layout may choose to wrap and increase height, clip, overlap, or otherwise constrain the children.

Specified by:

computeSize in class Layout

Parameters:

composite - a composite widget using this layout

wHint - width (SWT.DEFAULT for minimum)

hHint - height (SWT.DEFAULT for minimum)

flushCache - true means flush cached layout values

Returns:

a point containing the computed size (width, height)

See Also:

Layout.layout(org.eclipse.swt.widgets.Composite, boolean), Control.getBorderWidth(), Control.getBounds(), Control.getSize(), Control.pack(), "computeTrim, getClientArea for controls that implement them"

getSize

Point getSize(Control control,
              boolean flushCache)

layout

protected void layout(Composite composite,
                      boolean flushCache)

Description copied from class: Layout

Lays out the children of the specified composite according to this layout.

This method positions and sizes the children of a composite using the layout algorithm encoded by this layout. Children of the composite are positioned in the client area of the composite. The position of the composite is not altered by this method.

When the flush cache hint is true, the layout is instructed to flush any cached values associated with the children. Typically, a layout will cache the preferred sizes of the children to avoid the expense of computing these values each time the widget is layed out.

When layout is triggered explicitly by the programmer the flush cache hint is true. When layout is triggered by a resize, either caused by the programmer or by the user, the hint is false.

Specified by:

layout in class Layout

Parameters:

composite - a composite widget using this layout

flushCache - true means flush cached layout values

layoutHorizontal

Point layoutHorizontal(Composite composite,
                       boolean move,
                       boolean wrap,
                       int width,
                       boolean flushCache)

layoutVertical

Point layoutVertical(Composite composite,
                     boolean move,
                     boolean wrap,
                     int height,
                     boolean flushCache)