September 7, 2000 - Triggering an Action by a Property Change | WebReference

September 7, 2000 - Triggering an Action by a Property Change

Yehuda Shiran September 7, 2000
Triggering an Action by a Property Change
Tips: September 2000

Yehuda Shiran, Ph.D.
Doc JavaScript

Every object fires a PropertyChange event when one of its properties changes. You can use the onPropertyChange() event handler to do any additional actions, following the property change. The left image in the following pair changes when moused over or out. The right image in the following pair is programmed to do an extra action whenever one of its properties changes. It sets the left image to its initial GIF, (../bc.gif). Play around with the images: Here is the code that implements the above pair of images:

<IMG ID = "leftImg" SRC="../bc.gif"
 onMouseOver="this.src = '../gl.gif';" 
 onMouseOut="this.src = '../gr.gif';">
<IMG SRC="../bc.gif" onPropertyChange="leftImg.src = '../bc.gif';" 
 onMouseOver="this.src = '../gl.gif';" 
 onMouseOut="this.src = '../gr.gif';">

Notice how we access other elements. The left image is labeled with ID = "leftImg". The right image accesses the left image's SRC attribute as leftImg.src.

Learn more about dynamic styles in Column 66, Dynamic Styles.