APPLICATION DESIGN

Changing the position of a layer
When you create a layer, it contains default position values. You can change the position of a layer in several dimensions by changing its position values. Note that you specify a layer position in relation to the block that contains it (also called the parent element).

1. Select the layer.

2. Choose Layer - Layer Properties and click the Positioning tab.

3. Choose a position and position value, as described in the following table:

Layer PositionDescription Default value
TopSpecifies the location of the top edge of the layer."Auto" aligns the top of the layer vertically with its original location (insertion point).
LeftSpecifies the location of the left edge of the layer."Auto" aligns the left edge horizontally with its original location (insertion point).
WidthSpecifies the width of the layer, a value based on the location of its right edge relative to its left edge. One-third of the width of the window or the parent element, whichever applies.
HeightSpecifies the height of the layer, a value based on the location of its bottom edge relative to the top edge.One-third of the height of the window or the parent element, whichever applies.
Z-IndexSpecifies the stacking order of the layer; that is, how close to or far from the front of the parent element the layer is located.0; that is, in front of the parent element.

Table of values for layer positions
The following table summarizes the possible values for each position.
Layer PositionValueDescription
TopPixelsThe location in pixels from the top edge of the parent element.
InchesThe location in inches from the top edge of the parent element.
EmsThe location in em units from the top edge of the parent element.
PercentThe location from the top edge of the parent element, computed as a percentage of the height of the parent element.
CharactersThe location in characters from the top edge of the parent element.
AutoThe default location of the top edge. The layer top edge is aligned vertically with the top edge of the original insertion point.
LeftPixelsThe location in pixels from the left edge of the parent element.
InchesThe location in inches from the left edge of the parent element.
EmsThe location in em units from the left edge of the parent element.
PercentThe location from the left edge of the parent element, computed as a percentage of the width of the parent element.
CharactersThe location in characters from the left edge of the parent element.
AutoThe default location of the left edge. The layer left edge is aligned horizontally with the left edge of the original insertion point.
WidthPixelsThe layer's width in pixels.
InchesThe layer's width in inches.
EmsThe layer's width in em units.
PercentThe layer's width, computed as a percentage of the width of the parent element
CharactersThe layer's width in characters.
Auto"Auto" sets the width automatically based on the layer's contents.
HeightPixelsThe layer's height in pixels.
inchesThe layer's height in inches.
EmsThe layer's height in em units.
PercentThe layer's height, computed as a percentage of the height of the parent element.
CharactersThe layer's height in characters.
Auto"Auto" sets the height automatically based on the layer's contents.
Z-IndexIntegerA layer with a higher Z-Index value (for example, layer A) is located closer to the user; that is, it is stacked in front of a layer with a lower Z-Index value (for example, layer B). If the layers overlap and layer A is opaque, the contents of layer A obscure the contents of layer B. In addition, the contents of layer B cannot be clicked or selected, even if layer A is tranparent.

A negative Z-Index is placed behind the parent element's contents (so that it cannot be clicked or selected); a positive Z-Index (>=0) is placed in front of the parent element's contents (and prevents overlapped parent element content from being clicked or selected).


See Also