Image Maps in XHTML

Oxygen XML Editor includes support for image maps in XHTML documents. This feature provides an easy way to create hyperlinks in various parts of an image without having to divide the image into separate image files. In HTML, an image (in the form of an img element) may be associated with an image map (in the form of a map element) by specifying a usemap attribute on the img element. The visual Author editing mode includes an Image Map Editor that helps you to easily create and configure image maps.

Figure: Image Map Editor in XHTML

Image Map Editor Interface in XHTML

The interface of the Image Map Editor consists of the following sections and actions:
Toolbar
New Rectangle
Use this button to draw a rectangular shape over an area in the image. You can drag any of the four points to adjust the size and shape of the rectangle.
New Circle
Use this button to draw a circle over an area in the image. You can drag any of the four points to adjust the size of the circle.
New Polygon
Use this button to draw a polygon shape over an area in the image. This actions opens a dialog box that allows you to select the number of points for the polygon. You can drag any of the points to adjust the size and shape of the polygon.
Duplicate
Use this button to create a duplicate of the currently selected shape.
Delete
Use this button to delete the currently selected shape.
Undo
Use this button to undo the last action.
Redo
Use this button to redo the last action that was undone.
Show/Hide Numbers
Use this button to toggle between showing or hiding the numbers for the shapes.
Bring Shape to Front
Use this button to bring the currently selected shape forward to the top layer.
Bring Shape Forward
Use this button to bring the currently selected shape forward one layer.
Send Shape Backward
Use this button to send the currently selected shape back one layer.
Send Shape to Back
Use this button to send the currently selected shape back to the bottom layer.
Color Chooser
Use this drop-down menu to select a color scheme for the lines and numbers of the shapes.
Zoom Slider
Use this slider to zoom the image in or out in the main image pane.
Image Pane
This main image pane is where you work with shapes to add hyperlinks to multiple areas within an image. Use the mouse to move shapes around in the image to the desired area and drag the points on a selected shape to adjust its size and shape. It is easy to see which shape is selected in this image pane because the border of the selected shape changes from a solid line to a dotted line.
Area Properties
Href
Specifies the hyperlink target for the selected area. This will become the value of the href attribute for the particular area element. The possible values are:
  • An Absolute URL - A URL of another web site (for example, http://www.example.com/index.htm).
  • A Relative URL - A link to a file within your web site (for example, index.htm).
  • An Element - A link to the ID of an element within the page (for example, #top).
  • Other Protocols - A specified path using other protocols (such as https://, ftp://, mailto:, file:).
  • A Script - A link to a script (for example, javascript:alert('Hello');)
Alternate
The description for the selected area. The value is inserted in an alt attribute in the particular area element. This is a required attribute to present a text alternative for browsers that do not display images.
Target
Specifies where to open the linked resource. The allowed values are:
  • _blank - Opens the linked resource in a new window or tab.
  • _self - Opens the linked resource in the same frame as it was clicked.
  • _parent - Opens the linked resource in the full body of the window.
  • framename - Opens the linked resource in the named frame.

How to Create an Image Map in XHTML

To create an image map on an existing image in an XHTML document, follow these steps:
  1. Right-click the image and select Image Map Editor.

    Result: This action will apply an image map to the current image and open the Image Map Editor dialog box.

  2. Add hyperlinks to the image by selecting one of the shape buttons (New Rectangle, New Circle, or New Polygon).
  3. Move the shape to the desired area in the image and drag any of the points on the shape to adjust its size or form. You can use the other buttons on the toolbar to adjust its layer and color, or to perform other editing actions.
  4. With the shape selected, specify the hyperlink target in the Href field and enter a description for the selected area in the Alternate field.
  5. (Optional) Specify where the hyperlink resource will be opened in the Target field.
  6. If you want to add more hyperlinks to the image, select a shape button again and repeat the appropriate steps.
  7. When you are finished creating hyperlinks, click OK to process your changes.

Result: The image map is applied on the image and the appropriate elements and attributes are automatically added. In Author mode, the image map is now rendered over the image and its properties are displayed in a section below the image.

How to Edit an Existing Image Map in XHTML

To edit an existing image map, right-click the image and select Image Map Editor. This opens the Image Map Editor where you can make changes to the image map with a visual editor. You can also make changes to the XML structure of the image map in the Text editing mode.

Overlapping Areas

If shapes overlap one another in the Image Map Editor, the one on the top layer takes precedence. The number shown inside each shape represent its layer (if the numbers are not displayed, click the Show/Hide Numbers button on the Image Map Editor toolbar). To change the layer order for a shape, use the layer buttons on the Image Map Editor toolbar (, , , ).

If you insert a shape and all of its coordinates are completely inside another shape, the Image Map Editor will display a warning to let you know that the shape is entirely covered by a bigger shape. Keep in mind that if a shape is completely inside another shape, its hyperlink will only be accessible if its layer is on top of the bigger shape.

Warning: PDF output is limited to rectangular shaped image map objects. Therefore, if your image contains circles or polygons, those objects will be redrawn as rectangles in the PDF output. Keep in mind that this might affect overlaps in the output.