birt report barcode font Writing XML in Font

Drawing QR in Font Writing XML

Here s a typical scenario. One of the authors has a rather extensive collection of Flash books in his office. The collection expands and contracts based upon the current version of Flash, and he thinks it would be rather neat to keep a running inventory of his collection. Rather than list all 50 or 60 of them, he decides to start out with 5 core titles and grow from there. The reason for the 5 titles is simple: if he can get 5 books organized, then it is no big deal to get 50, 500, or even 5,000 books into the document. The decision is to start with books from friends of ED, and he decides to start with: ActionScript 3.0 Image Effects, Flash Applications for Mobile Devices, ActionScript for Animation, Foundation ActionScript 3.0, and Flash Math Creativity. Each book has its own page count, author, and publisher. Where to begin Let s take a look. Every XML document must have at least one tag, which constitutes its root element. The root element should describe the document s contents. In this case, we re dealing with Flash books, so let s make that our root: <flashbooks></flashbooks> The rest of our elements will stack themselves inside this first one. Every title is its own book, so we ll add five custom <book> elements: <flashbooks> <book></book> <book></book> <book></book> <book></book> <book></book> </flashbooks> Again, these tag names aren t things that exist in XML. It s up to you to decide which elements make sense for the data at hand, to name those elements accordingly, and then to use them. Note that each opening tag has a closing tag partner (with a slash in it), which is a characteristic required by the XML standard. If an element doesn t contain further data inside it, that element can optionally serve as its own opening and closing tags. In such a case, the <book></book> pairing would look like this: <book />. But here, each book has a title, so these elements will remain as tag pairs.

The next step adding a title seems obvious enough: <flashbooks> <book> <title> ActionScript 3.0 Image Effects </title> </book> <book> <title> Flash Applications for Mobile Devices </title> </book> <book> <title> ActionScript for Animation </title> </book> <book> <title> Foundation ActionScript 3.0</title> </book> <book> <title> Flash Math Creativity </title> </book> </flashbooks> The difference here is that the <title> tags contain textual data instead of additional elements, but you get the idea. Hold on a minute all of these tags contain data! The <title> tags contain text nodes (that is, nonelement text content), and the <book> and <flashbooks> tags contain XML element nodes (that is, descriptive tags). It doesn t take much effort to connect the rest of the dots. An excerpt of the completed document might look something like this: <flashbooks> <book> <title> Flash Applications for Mobile Devices </title> <publisher>friendsofED</publisher> <pageCount>663 pages</pageCount> </book> . . .</flashbooks> Actually, that isn t complete after all, is it The author is missing. The thing about these books is there may be one author on the cover or a number of authors on the cover. For that, another tier of elements is in order: <flashbooks> <book> <title> Flash Applications for Mobile Devices </title> <publisher>friendsofED</publisher> <pageCount>514 pages</pageCount>

XML (DYNAMIC DATA)

<authors> <author>Richard Leggett</author> <author>Weyert de Boer</author> <author>Scott Janousek</author> </authors> </book> . . . </flashbooks> That would certainly do it. The tag names are meaningful, which is handy when it comes time to retrieve the data. The nested structure organizes each concept into a hierarchy that makes sense. Nicely done, but in a sizable collection, this particular arrangement might come across as bulky. Is there a way to trim it down Sure thing. Remember that XML allows you to create your own attributes, so you have the option of rearranging the furniture along these lines: <flashbooks> <book title=" Flash Applications for Mobile Devices " publisher="friendsofED" pageCount ="514 pages"> <authors> <author>Richard Leggett</author> <author>Weyert de Boer</author> <author>Scott Janousek</author> </authors> </book> . . . </flashbooks> The exact same information is conveyed. The only difference now is that some of the data has been shifted to tag attributes, or attribute nodes, rather than tags. HTML provides the same mechanism, by the way. Consider the src attribute of an <img> tag (<img src="someImage.jpg" />). All it does here is change how the data would be retrieved, as you ll see in the Using E4X syntax section of this chapter. Which approach is better Honestly, the choice is yours. It s not so much a question of better as it is what best matches your sense of orderliness. Ironically, this open-ended quality, which is one of XML s strongest assets, is the one feature that is the hardest for those who are new to the subject to grasp. It doesn t have to make sense to anyone but you.

Working with and structuring an XML document follows the first principle of web development: No one cares how you did it. They just care that it works. Find what works best for you, because in the final analysis, your client will never pick up the phone and say, Dude, that was one sweetly structured XML document you put together. Having said that, if you are part of a collaborative work group, be sure that everyone involved agrees on terminology before you start.

Folks, this is a bit like a ceramics class. As long as you re careful around the kiln, no one can tell you whose vase is art and whose isn t. Just work the clay between your fingers, let a number of shapes mull

around your mind, and then form the clay into a structure that appeals to you. While you re at it, keep a few rules in mind: If you open a tag, close it (<tag></tag>). If a tag doesn t come in two parts that is, if it contains only attributes, or nothing at all make sure it closes itself (<tag />). Close nested tags in reciprocating <a><b><c /></a></b> will blow up ). order (<a><b><c /></b></a> is correct, but

Wrap attribute values in quotation marks or single quotation marks (<tag done="right" />, <tag done=wrong />). The flashbooks example we just discussed would be saved as a simple text file with the .xml file extension, as in flashBooks.xml. In fact, it isn t a bad idea, once you have finished writing your XML document, to open it in a browser like Firefox to see whether there are any problems. Now that our introductions have been made, let s get social.

Feel free to use a text editor such as Notepad on Windows or TextEdit on the Mac to create your XML files. Just be sure you add the .xml extension to the file s name. If you have Dreamweaver CS5, that s even better, because it automatically writes the document declaration for you at the top, and it offers tools such as code completion to speed up your workflow. Also, keep in mind that manually writing XML is just one approach. As you start becoming more comfortable with using XML, you will eventually find yourself drifting toward server-side scripting such as PHP to handle complex data management.