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Info + Web Tech Course

Info + Web Tech Course. Digital Media Production. Anselm Spoerri PhD (MIT) SC&I @ Rutgers University aspoerri@rutgers.edu anselm.spoerri@gmail.com. Lecture 3 – Overview. XHTML Elements Recap Hierarchy of Tags Block and Inline Elements div | id | class

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Info + Web Tech Course

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  1. Info + Web Tech Course Digital Media Production Anselm Spoerri PhD (MIT) SC&I @ Rutgers University aspoerri@rutgers.edu anselm.spoerri@gmail.com

  2. Lecture 3 – Overview XHTML Elements Recap • Hierarchy of Tags • Block and Inline Elements • div | id | class Cascading Style Sheet = CSS • Formatting Rules • Inline | Internal | External specification of CSS rules CSS Demo CSS Navigation using Lists Testing & Debugging Web Pages  Check Easy Stuff First Lectures – Week 3 Contenthttp://comminfo.rutgers.edu/~aspoerri/Teaching/DMPOnline/Lectures.html#week3

  3. Recap & New– Web Basics: HTML Elements & Tags • HTML is made up of elements • <tag>Content</tag>(read as: open tag, content, close tag) • Three major elements needed on HTML page • <html> - container for all of our HTML code • <head> - put data for browser and other machines • <body> - put content to show to the user • Block-level elements  take up own space vertically(<p>, <h1>, <h2>, ...) • <div> page division • Inline-level elements placed inside other elements (<a>, <img>, <strong>, <em>, …)

  4. Page Layout – DIVs • Two methods for creating Web Page Layout • Tables (last lecture) • DIVs and CSS (this lecture) • Structure Your Pages URL • Divide logical sections of document into div elements •  Produces “linear / natural flow” of divs • pageContent • header • navigation • main content • footer <div> <div> header content </div> <div> navigation content </div> <div> main content </div> <div> footer content </div> </div>

  5. Page Structure – Hierarchy & Naming Elements • Body of (X)HTML document encloses Content of Web page. • Breaking up Page into Divisions (DIV) • Creating a Line Break: <br /> • Hierarchical Structure of Web pages • Elements contained inside another element (latter = parent, former = child) • Naming Elements • id="name"can be applied only once  unique #idName {…} define CSS rule • class="name"can be applied many times .className {…} define CSS rule • Useful with div (content blocks) and span (inline text) elements

  6. Page Layout – DIVs with IDs • Name div elements with unique IDs • pageContent • header • navigation • main content • footer <div id="pageContent"> <div id="header"> text/images/links </div> <div id="navi"> text/images/links </div> <div id="content"> text/images/links </div> <div id="footer"> text/images/links </div> </div>

  7. CSS • Cascading Style Sheets = CSS • Collection of Formatting Rules • Control Appearance of web page: blocks and text • Ensure a more Consistent Treatment of Page Layout and Appearance in Browsers • Separation of Content from Presentation • Easier to Maintain Appearance since Make Change in Single Location • Simpler and Cleaner HTML code  shorter loading times

  8. CSS (cont.) • Cascading Style Sheets (CSS) • Control Text properties • Specific fonts and font sizes; bold, italics, underlining, and text shadows; text color and background color; link color and link underlining; etc. • Control Format & Position of Block-level Elements • Set margins and borders for block-level elements; position them in a specific location; add background color; float text around them; etc. • Liquid layouts: expand/contract based on Browser width. • Easy to apply Same Layout to Whole Site and only need to modify external CSS file. • Minus: Not all browsers support CSS the same way.

  9. CSS (cont.) • CSS Style Sheet stored • External CSS style sheet (.css file linked to page and using a link or an @import rule in the head section of a document). • Internal (or embedded) CSS style sheet (included in style tag in head portion of an HTML document). • Inline styles (defined within specific tag instance in HTML document) Using Inline styles is not recommended. • CSS Rule = Selector and Block of Declarations • Enclosed by {...} brackets and separated by ; • Declaration = Property: Value;

  10. CSS – General Structure of CSS Rule • Basic syntax for Internal and External CSS: selector {property1: value1; property2: value 2;} HTML tag you want to modify Value you want property to take Property you want to change p { text-align: left; color: black; font-family: Arial; } • causes • Font to be left-aligned • Font to be Arial and black

  11. CSS Rules – id and class Rules in Internal Style Sheet • <head> • <style type="text/css"> • /* Comment: pageContent ID and define font to use for page and the top and left margins as well page width. This pageContent div contains all the other divs */ • #pageContent { • font-family: Verdana, Geneva, sans-serif; • font-size: 12px; • margin-top: 10px; • margin-left: 50px; • width: 500px; • } • /* blue text class */ • .blueText { • color:#009; • } • </style> • </head>

  12. CSS Rules – id and class Rules Applied in <body> • <body> • <div id="pageContent"> • <div id="content"> • <h1>Heading1</h1> • <p class="blueText">Open paragraph</p> • </div> • </div> • </body>

  13. Location of CSS Style Definition • Inline style(causes only the tag to have desired properties) <p style="font-family:Arial; color:blue">Something blue </p> • Internal stylesheet(specific to a document) • Causes all tags in document to have property • <style> tag inside<head> tag of document <head> <style type="text/css"> p { font-family:Arial; color:blue;} </style> </head> • External stylesheet(can control multiple documents) • Ensure consistent appearance of website <head> <link rel="stylesheet" href="mystyle.css" type="text/css" /> </head>

  14. CSS – Cascasde of How Rules are Applied • Style Rules “Cascade” from broad to narrow: • Browser’s Default Behavior • External Style Sheet • Internal Style Sheet • Inline Style

  15. CSS Demo – Step 1 • Step 1 • Download “startPage.html” fromhttp://comminfo.rutgers.edu/~aspoerri/Teaching/DMPOnline/Lectures/Lec3/Steps • Save “startPage” as “page1.html” in folder “week3” • Create nested div structure pageContent, header, navi, content, footer • Assign id name to div

  16. CSS Demo – Step 2 • Step 2 • Create Internal CSS Style Sheet <style type="text/css"> • Create CSS Rule for id="pageContent" font-family: Verdana, Geneva, sans-serif; font-size: 12px; margin-top: 10px; margin-left: 50px; width: 500px; • Create CSS Rule for class="blueText" color:#009;

  17. CSS Demo – Step 3 • Step 3 • Create CSS Rule for id="header" font-size: 9px; border-bottom-width: thin; border-bottom-style: solid; border-bottom-color: #333; • Create CSS Rule for id="navi" font-size: 14px; background-color: #E1E3F7; padding: 5px; margin-top: 5px;

  18. CSS Demo – Step 4 • Step 4 • Create CSS Rule for id="content" font-size: 12px; • Apply class="blueText" <p> tag inside div with id="content" • Create CSS Rule for id="footer" font-size: 10px; border-top-width: thin; border-top-style: solid; border-top-color: #666;

  19. CSS – Navigation Bar using Lists and CSS • <ul> • <li><a href="home.html">Home</a></li> • <li class="here"><a href=“features.html">Features</a></li> • </ul> • CSS property - display: block; and float: left; and clear: both; • Hyperlink States: a:link | a:visited | a:focus | a:hover | a:active Navigation = Lists of Links example

  20. CSS – Navigation Bar using Lists and CSS (cont.) • Remove Bullets, Eliminate Padding and Margins #naviul { list-style-type: none; padding: 0px; margin: 0px; overflow: hidden; } • Display Link as Block (area of link clickable) and Constrain Width • #navia{display: block;width: 100px; } • Horizontal Navigation • Use floated <li> method for uniform look • #navili { float: left; } • You are Here Indicator • #navili.here a{ text & background properties } • and want CSS rules for different states of hyperlink

  21. CSS – Navigation Bar and States of Link Element • Selecting Link Element based on their State Navigation Structure • Since a link can be in more than one state at a time, it is important to define rules in following order: • a:link • a:visited • a:focus • a:hover • a:active  LVFHA a:link, a:visited { color: #FFF; } a:focus, a:hover, a:active { color: #000; } #navi a:link, #navi a:visited { color: #FFF; } #navi a:focus, #navi a:hover, #navi a:active { color: #000; }

  22. Testing & Debugging Web Pages • Before looking for a big problem, check common little problems :) • Work incrementally • Use process of elimination (use comments to make code active / inactive). • Be careful about typos. • In CSS, not sure if the problem is with the property or the selector, use a very simple declaration (color: red).

  23. Check Easy Stuff First - General • Refresh browser so that latest file is shown • Upload actual file and refresh browser so that latest file is shown • Upload file in the correct location • Make sure you save file • Upload any related files: CSS, images, SWF etc. • Make sure spelling of URL = spelling of filename. • Test in multiple browsers • Test on different computer than the one used to create the files

  24. Check Easy Stuff First – HTML & XHTML • HTML • Make sure you used correct spelling of tags • Be careful about nesting and make sure you have closing tags • Use HTML Transitional • XHTML • Make sure all attribute value enclosed in straight, not curly, quotes • All elements have opening and closing tags (always put space before / for “ />” closing tag). • XHTML is case-sensitive. • Include # when specifying hexadecimal colors.

  25. Check Easy Stuff First – CSS • Use colon (:) to separate your properties from value (color: red;). • Complete each property-value pair with semicolon (;) • No spaces between number and their units (16px). • Close brackets. • Don’t quote values. • Use accepted value. • Don’t forget closing < /style> tag. • Make sure linked (X)HTML document to the proper CSS file(s). • Watch the spaces and punctuation between selectors.

  26. Check Easy Stuff First – Testing Your Page • Validate (X)HTML and CSS. • Open in Browser • Formatting correct? • Hyperlinks work & correct? • CSS file referenced properly? • All images appear?If not, check the easy stuff first, especially spelling of filenames and don’t use spaces in filenames and saved as GIF or JPEG. • Upload files to server (and set permissions if needed). • View pages in different browsers. • Still Stuck check for typos and check easy stuff first :)

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