tailieunhanh - JavaScript Bible, Gold Edition part 136

JavaScript Bible, Gold Edition part 136. This book will bring programmers and non-technical professionals, including casual programmers and scripters, painlessly up to speed on all aspects of mastering JavaScript. Key topics include programming fundamentals, JavaScript language elements and how to use them effectively, and how to easily and efficiently add powerful new functionality to HTML documents and Java applets. | 1198 Part V Putting JavaScript to Work Using EMBED The preferred way to embed such content into a page for NN all OSes and IE Mac is to use the EMBED tag. Even though the W3C HTML standard does not recognize the EMBED element it has been a part of browser implementations since the first embeddable media. The element is also a bit of a chameleon because beyond a common set of recognized attributes such as the SRC attribute that points to the content file to be loaded into the plug-in its attributes are extensible to include items that apply only to a given plug-in. Uncovering the precise lists of attributes and values for a plug-in is not always easy and frequently requires digging deeply into the developer documentation of the plug-in s producer. It is not unusual for a page author to anticipate that multiple plug-ins could play a particular kind of data as is the case in the audio examples later in this chapter . Therefore a single EMBED element may include attributes that apply to more than one plug-in. You have to hope that the plug-ins developers chose unique names for their attributes or that like-named attributes mean the same thing in multiple plug-ins. Any attributes that a plug-in doesn t recognize are ignored. Typical behavior for a plug-in is to display some kind of controller or other panel in a rectangle associated with the media. You definitely need to specify the HEIGHT and WIDTH attribute values of such an EMBED element if it is to display visual media some video plug-ins let you hide the controls while still showing the viewing area . For audio however you can specify a one-pixel value for both dimensions and leave the controls to your HTML content. Browsers that recognize style sheets can also set EMBED elements to be invisible. As an example of what an EMBED element may look like the following is adapted from Listing 44-9. The example includes attributes that apply to QuickTime and LiveAudio and is formatted here for ease of readability. EMBED .