Documentation

null Layout

null layout is not a real layout manager. It means that no layout manager is
assigned and the components can be put at specific x,y coordinates.

It is useful for making quick prototypes. But it is not recommended for
production because it is not portable. The fixed locations and sizes do not
change with the environment (e.g. different fonts on various platforms).

Preferred sizes¶

JFormDesigner supports preferred sizes of child components. This solves one
common problem of null layout: the component sizes change with the environment
(e.g. different fonts on various platforms). Unlike other GUI designers, no
additional library is required.

To make it easier to align components, the component edges snap to an invisible
grid when moving or resizing components. You can specify the grid step size in
the Preferences dialog. To temporary disable
grid snapping, hold down the Shift key while moving or
resizing components.

You can move selected components with Ctrl+ArrowKey and
change size with Shift+ArrowKey.

Aligning components¶

The align commands help you to align a set of components or make them same width
or height.

The dark blue handles in the above screenshot indicate the first selected
component.

Command
Description

Align Left
Line up the left edges of the selected components with the left edge of
the first selected component.

Align Center
Horizontally line up the centers of the selected components with the
center of the first selected component.

Align Right
Line up the right edges of the selected components with the right edge
of the first selected component.

Align Top
Line up the top edges of the selected components with the top edge of
the first selected component.

Align Middle
Vertically line up the centers of the selected components with the
center of the first selected component.

Align Bottom
Line up the bottom edges of the selected components with the bottom edge
of the first selected component.

Same Width
Make the selected components all the same width as the first selected
component.

Same Height
Make the selected components all the same height as the first selected
component.

Make Horizontal
Space Equal
Makes the horizontal space between 3 or more selected components equal.
The leftmost and rightmost components stay unchanged. The other
components are horizontally distributed between the leftmost and
rightmost components.

Make Vertical
Space Equal
Makes the vertical space between 3 or more selected components equal.
The topmost and bottommost components stay unchanged. The other
components are vertically distributed between the topmost and bottommost
components.

Layout manager properties¶

A container with this layout manager has following
layout manager properties:

Property Name
Description
Default

auto-size
If true, computes the size of the container so that all children are
entire visible. If false, the size of the container in the Design view
is used.
true

Layout constraints properties¶

A component contained in a container with this layout manager has following
layout constraints properties:

Property Name
Description
Default

x
The x coordinate of the component relative to the left corner of the
container.
0

y
The y coordinate of the component relative to the upper corner of the
container.
0

width
The width of the component in pixel or Preferred. If set to Preferred,
the component’s preferred width is used.
Preferred

height
The height of the component in pixel or Preferred. If set to Preferred,
the component’s preferred width is used.
Preferred