The layout and layoutH parameters are in the following format: ":rows:cols:type:k:l:h:w:anchor:fill:[weighty:[weightx:]]type:k:l:...", where : is the field separator, rows is the number of rows in the cell, cols is the number of columns, type is the type of the component in row k, column l of the current cell, h is the height of the component (rows), w is the width (columns).
The anchor parameter determines where to place the component if its size is smaller than its display area. It the component size is larger than the size of its text label, then anchor also sets the label alignment. Possible values: c (center), n (north), s (south), e (east), w (west), ne (northeast), etc.
The fill parameter determines how to resize the component if its size is smaller then its display area. Possible values: n (none), h (horizontal), v (vertical) or b (both).
The weights are nonnegative integers, zero by default. They determine how to distribute space. If all the weights are zero, all the components clump together in the center of the applet.

If you are familiar with Java, you might have noticed that anchor, fill, weightx and weighty have the same names as the fields of the GridBagConstraints class. The reason is that MarvinView uses the GridBagLayout class to determine the places and sizes of the components.

Component types: M (molecule), L (label), B (button), C (checkbox), T (text field) and I (image).

Example:

<param name="layout" value=":4:3:
M:0:0:4:1:c:n:
L:0:2:1:1:c:n:0:10:
L:1:2:1:1:c:n:0:10:
C:0:1:1:1:c:n:
C:1:1:1:1:c:n:
C:2:1:1:1:c:n:
B:3:1:1:1:c:n:10">