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With this tag you can create several layers of content on a page. These layers can be stacked on top of each other, showing parts of underlying layers through non-occupied space. You can control the order of the layers, the position on the page and if a layer is visible or not. |
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ABOVE![]() |
This attribute controls the stacking of the layers, in relation to other layers.
With it you specify which layer is positioned immediately above the layer being
defined. The value supplied must be the NAME of that layer.
The attributes ABOVE, BELOW and Z-INDEX are mutually exclusive, so if you use this attribute, the attributes BELOW and Z-INDEX cannot be used. |
BACKGROUND![]() |
Supply an image that is used as the background of the layer. If the space that
the layer occupies is larger than the image, the image is tiled to fill up the
used space. You can use images in the GIF and JPEG format. If you use an transparent image the transparent parts will be shown in the background color, or the HTML elements of underlying layers. |
BELOW![]() |
This attribute controls the stacking of the layers, in relation to other layers.
With it you specify which layer is positioned immediately below the layer being
defined. The value supplied must be the NAME of that layer.
The attributes ABOVE, BELOW and Z-INDEX are mutually exclusive, so if you use this attribute, the attributes ABOVE and Z-INDEX cannot be used. |
BGCOLOR![]() |
Set the background color of the layer, hiding all elements of layers below it.
See the page Using colors for a description on specifying colors. |
CLIP![]() |
This attibute determines the clipping rectangle of the layer, that is, it
defines the boundaries of the visible area of the layer.
The value is a set of 4 numbers, indicating in order, the left value, the top value, the right value, and the bottom value. The left and right values are specified as pixels in from the left, while the top and bottom values are specified as pixels down from the top of the containing document or layer. Each of the 4 values are numbers of pixels. You can also specify the value as a set of 2 numbers, in which case the left and top values default to 0. For example:
is equivalent to
If you do not supply this attribute, the clipping rectangle of a layer is determined by the values of WIDTH and HEIGHT. By default, a layer expands to contain all of its content. |
HEIGHT![]() |
The HEIGHT parameter determines the initial height of the clipping region of
the layer. The height can be expressed as an integer pixel value, or as a
percentage of the height of the containing layer (or the window for a top-level
layer.)
Note however that if the contents of the layer do not fit inside the specified height, the layer will expand its height to include all its contents. The main purpose of hte HEIGHT attribute is to act as the reference height for attribute values in its children layers that are specified using percentages. This attribute is optional; by default, the layer height is the minimum height that contains all the layer contents. |
ID![]() |
Generic description of the ID attribute |
LEFT![]() |
The LEFT parameter specifies the horizontal position of the top left corner of
the layer within its containing layer, or within the document if it is at the
top level. The attribute is optional. The default value is the horizontal
position of the tag's contents as if they were not enclosed in a layer.
For positioned layers the origin is the upper-left-hand corner of the document or containing layer, with coordinates increasing downwards and to the right. |
NAME![]() |
The NAME parameter is an identification tag for the layer. The NAME must begin
with an alphabetic character. (The NAME parameter is the same as the ID
parameter.)
You can use the layer's name to refer to the layer from within HTML and external scripting languages such as JavaScript. This attribute is optional; by default, layers are unnamed. |
OnBlur![]() |
This is an event handler. The value must be a function or inline Javascript code. The onBlur handler is invoked when the layer loses keyboard focus. |
OnFocus![]() |
This is an event handler. The value must be a function or inline Javascript code. The onFocus handler is invoked the layer gets keyboard focus. |
OnLoad![]() |
This is an event handler. The value must be a function or inline Javascript code. The onLoad handler is invoked when the layer is loaded, regardless of whether the layer is visible or not. |
OnMouseOut![]() |
This is an event handler. The value must be a function or inline Javascript code. The onMouseOut handler is invoked when the mouse leaves the layer. |
OnMouseOver![]() |
This is an event handler. The value must be a functions or inline Javascript code. The onMouseOver handler is invoked when the mouse enters the layer. |
PAGEX![]() |
The PAGEX parameter specifies the horizontal position of the top left corner of the layer relative to the enclosing document (rather than the enclosing layer.) |
PAGEY![]() |
The PAGEY parameter specifies the vertical position of the top left corner of the layer relative to the enclosing document (rather than the enclosing layer.) |
SRC![]() |
The SRC parameter specifies an external file that contains HTML-formatted text
to be displayed in this layer.
The file specified by SRC can contain an arbitrary HTML document. The source file can include JavaScript code. Any LAYER tags in the source file will be treated as child layers of the layer for which the source file is providing content. The SRC parameter is particularly useful if you want to dynamically change the content of the layer. For example, a restaurant might have a web page that uses a layer to describe the special meal of the day. Each morning, after the chef has decided what the special is going to be for the day, he or she quickly edits the file "special.htm" to describe the meal. The chef doesn't have to re-write the entire page just to update the information about the special of the day. |
TOP![]() |
The TOP parameter specifies the vertical position of the top left corner of the
layer within its containing layer, or within the document if it is at the top
level. This attribute is optional. The default value is the vertical position
of the tag's contents as if they were not enclosed in a layer.
For positioned layers the origin is the upper-left-hand corner of the document or containing layer, with coordinates increasing downwards and to the right. |
VISIBILITY![]() |
The VISIBILITY parameter determines whether the layer is visible or not. A
value of HIDE hides the layer; SHOW shows the layer; INHERIT causes the layer
to have the same visiblity as its parent layer. For top level layers (that is,
layers that are not nested inside other layers, a value of INHERIT has the same
effect as SHOW since the body document is always visible.)
This attribute is optional. By default, a layer has the same visibility as its parent layer, that is, the value of the VISIBILITY attribute is INHERIT. Remember that even if the visibility of a layer is is set to SHOW, you will only be able to see the layer if there are no other visible, opaque layers stacked on top of it.
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WIDTH![]() |
The WIDTH parameter determines the width of the layer. The width can be
expressed as an integer pixel value, or as a percentage of the width of the
containing layer.
Note however that if the elements that cannot be wrapped, such as images, extend beyond the width specified, the actual width of the contents of the layer will expand accordingly. This attribute is optional; by default, the layer contents wrap at the right boundary of the enclosing layer. |
Z-INDEX![]() |
This attribute controls the stacking of the layers, in relation to other layers.
With it you specify at which position in the stack of layers you want to put
the layer that you are creating. The number you supply is relative to the
parent layer, that is, the layer in which this layer is defined. A positive
value stacks the layer above the parent layer, a negative value below it.
The attributes ABOVE, BELOW and Z-INDEX are mutually exclusive, so if you use this attribute, the attributes ABOVE and BELOW cannot be used. |
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Source: | <A HREF=LAYER1.html>Take a look at the LAYER example</A> |
Result: | Take a look at the LAYER example |