Intermediate Web Publishing: Working with Styles

Transcription

1 Intermediate Web Publishing: Working with Styles Jeff Pankin Information Services & Technology

2 Contents Introduction... 2 In this class you will:... 2 Set the Preferences... 2 General... 2 Invisible Elements... 2 New Document... 2 Preview in Browser... 2 Define a Site... 3 Set up Dreamweaver to Upload Files... 3 Note: Dependent files refer to page images and linked stylesheets... 4 How to View Your Pages on the Web... 4 Create the First Web Page... 4 The index.html web page so far... 5 Cascading Style Sheets (CSS)... 6 About Styles... 6 Basic CSS Syntax... 7 The CSS Panel... 9 Create a Tag Style... 9 The Rule Definition Dialog Box Editing Styles Text Properties for h Create a Class Style To Center Text Apply a Class Style to a Tag Apply a Class Style to Selected Text Link to an External Style Sheet Background Properties The Box Model More about the box model Some shortcuts for box property values Understanding Float... 15

3 Float Exercise: Understanding Position Advantages of Absolute Positioning Disadvantages of Absolute Positioning Advantages of Using Float Layout Disadvantages of Float Layout Some ways to think about web page layout Creating a Page Layout with CSS Positioning Positioning using Float Creating a Float Layout Descendant Selectors continued Format the Menu Pop-up Menus Creating a Print Style Sheet Validating your CSS Resources Copyright 2010 by Massachusetts Institute of Technology. All Rights Reserved.

4

5 Introduction In this class you will: review the basics of working with styles to establish the look-and-feel throughout a site use Dreamweaver to create, edit, apply and manage styles use styles with background images use CSS positioning for the layout of a web page use CSS to design menus Set the Preferences Win: Edit menu > Preferences Mac: Dreamweaver menu > Preferences General Check Use <strong> instead of <b> and <em> instead of <i> Uncheck Use CSS tags instead of HTML tags Invisible Elements Check all New Document Default document: HTML Default extension:.html Default Document Type (DTD): XHTML 1.0 Transitional Preview in Browser set up the Firefox browser as primary browser

6 Define a Site We define a site in Dreamweaver to identify the location of our web files. This allows Dreamweaver to track and automatically update links when we change a file name or move a file. Also, when we define a site we can use Dreamweaver's secure FTP to move our files to our Athena locker. Step 1 - create or choose a local root folder Step 2 - in Dreamweaver choose Site menu > New Site Step 3 - name your site (could be anything; best practice: use same name as root folder) Step 4 use the Browse icon to show Dreamweaver your local root folder Set up Dreamweaver to Upload Files 1. From the Site menu choose Edit Sites. 2. Select the desired site, and click Edit Click on the Advanced tab -- if not already there -- and select Remote Info from the Category list on the left. 4. On the Remote Info dialog, select or enter the following then Click OK. Below are the settings for Dreamweaver for both Windows and Macintosh computers. Full instructions for configuring connections with Dreamweaver are also available online at FTP Host Host Directory sun.dialup.mit.edu example path for department locker /afs/athena.mit.edu/org/c/chemistry example path for personal locker /afs/athena.mit.edu/user/p/a/pankin/www Note the use of the first two letters for user name but first letter only for org name. Login Password Use Passive FTP Use Firewall Use Secure FTP (SFTP) Kerberos username Leave blank Check this option. Uncheck this option. Check this option. Click the Expand/Collapse button to switch to a split view of your Remote files and Local files. Click to return to the normal Files panel view.

7 In the split view click on the small plug icon between the remote site and your local site. to connect. You can now move files securely Note: Dependent files refer to page images and linked stylesheets. How to View Your Pages on the Web When you have uploaded your pages, you can go see them in a browser by typing the url. Your url will follow the convention shown here: Organization url: web.mit.edu/org name (e.g. or Personal url: (e.g., Create the First Web Page 1. Create a new Basic HTML page 2. Open the file "source.txt" 3. Copy the text and paste into your new document 4. Format headings and blockquote 5. Add a title 6. Save as index.html 7. Preview, upload, view live page

8 The index.html web page so far Web Publishing Basics

9 Cascading Style Sheets (CSS) Originally the web was used by academics to share scientific papers. HTML tags were designed to give structure to these papers. As the web came to be used commercially developers wanted to use fonts, color and other kinds of formatting. Internet Explorer and Netscape added the <font> tag to their browsers to allow formatting to be embedded in HTML documents. The World Wide Web Consortium (W3C) the international standards body for the web created styles and stylesheets in 1996 at the time they released the standards for HTML 4.0. Stylesheet definitions provide consistent formatting for a web page or an entire site. After introducing CSS, the W3C recommended that certain formatting tags in HTML (e.g., the <font> tag) be phased out and replaced by styles. About Styles 1. A style is a collection of formatting (e.g., bold, blue, 24px). By applying a style to content all the formatting in the style is applied at once. 2. When the formatting of a style is changed all content with that style gets updated automatically. 3. Styles may be located in the <head> of a web document available only to that document. Or they may be kept in a separate file and used by some or all the pages in a web site. CSS gives more control over font size, background images, placement of items, layout of pages and the way links function! Also we can apply styles to one area and not another. Without the use of CSS browsers may interpret html individually.

10 Basic CSS Syntax I. A style definition contains three parts: a selector, a property and a value. selector {property: value} h1 {color: red} selector 1. the name of a tag (tag) 2. a name you create (class) 3. the name of a div (id) property the attribute you wish to change h1, p, body.mystyle,.align-table #header #nav font-size, font-family, color value what the attribute will change to 24px, times new roman", blue A class style names begin with a period. An id styles begins with a # (hash mark). Values with more than one word are in quotation marks. II. This is the format for styles placed in the <head> of an html document. Include the bold html tags. <head> </head> <style type="text/css"> h1 {color: red} </style> Styles placed in a cascading stylesheet document (.css extension) require only the style, not the html tags. body {font-family: arial, times new roman } h1 {color: red} h2 {color: blue} Styles in the head of a document are only available in the document where they are located. Styles in a.css document may link to any html document. <link href="stylesheet.css" rel="stylesheet" type="text/css" />

11 III. A single style declaration may include multiple selectors separated by commas. h1, h2 {color: red} A single style declaration may include multiple property/value pairs separated by a semicolon. h1 {color: red; font-family: arial} IV. A tag style affects all content using that style. If the h1 tag is defined to be red then every use of h1 will be red. A class style is: 1. given a user defined name which begins with a period 2. applied to content as needed Example: a style named.red may be applied to any content single characters, phrases, sentences and any individual tag. V. Tag style formatting is applied when the tag is used. Class style formatting must be applied by you. To apply a class style to a block level tag add the class attribute to the open part of the tag. <p class="red">welcome to the MIT Watercolor Club Home Page</p> To apply a class style to inline content surround the content with the <span> tag and add the class attribute to the open part of the span tag. <p>welcome to the <span class="red">mit Watercolor Club</span> Home Page.</p> Drop the period from the name of a class style when it is applied.

12 The CSS Panel You can control all styles activity through the CSS panel. Close the Files panel to allow more room in the panel area for the CSS panel. (at cursor location) Create a Tag Style

13 The Rule Definition Dialog Box The Rules Definition Dialog box is a convenient place to choose properties and attributes for a style definition. Clicking a category brings into view properties associated with that category. Editing Styles 1. Double click any style name to open Rule Definition dialog for that style. 2. Edit one of your styles and click the Apply button to see your changes in the window behind the dialog box. 3. Edit a style in the CSS panel. Text Properties for h1 Property Font Size Weight Style Variant Line Height Case Decoration Color Value Verdana, Arial, Helvetica, sans-serif 30px leave blank [Note: only Bold has been implemented in browsers] leave blank [Note: only Italic has been implemented in browsers] leave blank [Note: won't show in Dreamweaver; Preview in Browser to see] leave blank [Note: HTML does not provide a means to control this property] leave blank underline confuses with link none we'll use with link to take out underline to create button choose from picker or enter # six digit code

14 Create a Class Style 1. Create a new class style named.copyright 2. Choose - Size: 12 pixels, Style: italic, color: maroon 3. Exit the dialog box and apply the style.copyright To Center Text Use the property value pair text-align: center" in the Block category. Note: This is a block level property. It will not work if text is selected. Apply a Class Style to a Tag To apply a class style to a tag, click on the tag and select the style from the pop-up menu on the Properties panel. Tag selector bar Code View <p.copyright> <p class="copyright">copyright 2007 MIT </p> Apply a Class Style to Selected Text To apply a class style to selected text, select the text and select the style from the pop-up menu on the Properties panel. Tag selector bar Code View <span.copyright> <span class="copyright">mit</span>

15 Link to an External Style Sheet To link to an existing stylesheet open the Style popup menu on the Properties Panel and choose Attach Style Sheet. Background Properties Choose Background from the category list. Property Value Background-color use the color picker pop-up or type in a color code [e.g., #3388FF] Background-image select an image for the background default position is upper left corner Background-repeat repeats the background image throughout the page or on the X or Y axis Background-attachment use fixed to prevent the image from scrolling Background-position (X) left, center, right or amount in pixels Background-position (Y) top, center, bottom or amount in pixels

16 The Box Model To ensure consistency across browsers, the w3c developed standards for the way browsers should interpret margins, borders and padding of an element. These standards are referred to as the Box Model. The basic idea is that every element has a margin, border and padding on the top and bottom as well as the left and right. Each of these may be styled differently using the appropriate property name. Things to know about the Box Model: all elements have the option to display borders, padding and margins - they are set to 0 by default margins are transparent, picking up the color of their enclosing element top and bottom margins are merged using the higher margin value or to the size of one value if they are the same size there is a shorthand for designating different sides

17 More about the box model content padding border margin The content area holds the content of the element. Padding creates visual space around the content. Border surrounds the content and padding and gives a visual boundary. Margin surrounds the border, padding and content and allows for space between the element and other elements. a background color or image will show under content and padding but not the margin padding and margins may be set in pixels, percents or ems border size may be set in pixels or by the keywords thin, medium or thick border styles include solid, dotted, dashed, double and others Some shortcuts for box property values to specify sides for margin or padding zero padding: 10px; [top right bottom left all 10px] padding: 10px 5px [top and bottom 10px, left and right 5 px] padding: 10px 20px 5px [top 10px, left and right 20px, bottom 5px] a value of zero does not require a measurement type border border: solid 2px green [solid, green border 2px thick on all sides] border: solid [solid black 3px border on all sides] Note: values may be in any order. For more info on css-shorthand see:

18 Understanding Float Things to know about Float: elements on a web page are placed in the document flow from top to bottom block elements have a line break between them and span the width of the screen an element with the float property is removed from the normal flow and placed on the left or right floated elements sit over other block elements and won't disrupt their flow (although may re-route it) content which follows a floated element in the code moves up but respects the floated element's boundaries and flows around it the clear property ensures that a floated element will be placed under (or clear of) other block elements a floated element must have a width unless it's an image

19 Float Exercise: 1. Add the image franklin.jpg to the paragraph About the Director. 2. Float the head shot to the left. Add padding right and bottom. 3. Create a sidebar using a div and float it to the right of the first paragraph. Add padding and margin left and bottom. 4. Format the div.

20 Understanding Position Things to know about Positioning: elements on a web page are placed in the document flow from top to bottom block elements have a line break between them and span the width of the screen inline elements flow left to right and lines expand vertically if more content is added there are four values for position: static, absolute, fixed, and relative the properties top, right, bottom, and left are used to position an element positioning an element means removing it from the normal flow static absolute fixed relative places element in the normal flow; this is the default so it's used to override another positioning value places an element anywhere on the page determined by top, bottom, left and right values; placement is relative to the sides of the page or the containing element places an element anywhere on the page determined by top, bottom, left and right values; placement is relative to the browser window and does not move when the page is scrolled other content moves underneath it normal flow is set then position is offset by value for top, bottom, left or right from its location in normal flow Use top, bottom, left and right to position an element from an edge. Use width to set the width of the content area.

21 More about positioning for layouts: to layout a page with CSS developers use either positioning or floats, each has its advantages and drawbacks absolute positioning allows precise placement but is more difficult and inflexible the use of floats is the most widely used layout method CSS positioning uses divs instead of table cells a div contains content, marks a logical grouping and is treated as a block with a line break before and after a div is created for each major section i.e., header, nav, content, sidebar and footer sometimes a div may be wrapped around several divs (a wrapper or container) allowing some formatting to be set once in the wrapper each div is usually given a unique id which allows for individualized styling Advantages of Absolute Positioning "absolute" control of where things are placed the structural order of content does not matter (useful for placing content before navigation which is good for accessibility and search engine optimization) Disadvantages of Absolute Positioning if you are not careful positioned content can overlap other content it's difficult to place the footer to adjust for column height Advantages of Using Float Layout can be simpler than positioned layout more widely used avoids need to set top property for footer on each page to accommodate varying amounts of content Disadvantages of Float Layout may require moving content around in code may be less effective for accessibility and search engine optimization

22 Some ways to think about web page layout Fixed (Frozen) 1. page content width remains the same regardless of widow size 2. may be left aligned or more typically centered 3. allows more precise control of design but may not use browser window width effectively 4. width set at either 760px for 800x600 screen/resolution size or 950px for 1024x760 screen/resolution size Liquid (Elastic) 1. content width expands or contracts based on browser width and/or font size 2. a bit more challenging to achieve but makes better use of the browser window width 3. widths are fixed but defined in ems so a change in font size will change the width, which allows user to adjust font size Jello* (something between Fixed and Liquid) 1. content area is fixed width set in center 2. margins are made liquid by using auto value for margin width 3. change in browser window width expands or collapses margins until it begins to cover fixed width content 4. has similar advantages to fixed layout in terms of precise design control * attributed to Mike Purvis, We will create a Jello layout using floated elements.

23 Creating a Page Layout with CSS Positioning There are several considerations before designing your web page layout. 1. Will you use a fixed width or liquid design layout, or something in-between? Your audience may view your pages on different sized monitors, using different resolutions, with different sized browser windows. Some may be viewing your pages with a text-only browser or on a mobile device with a very small screen. A liquid design allows web content to expand or contract gracefully into whatever size space it is given. Part of designing liquid layouts is through the use of relative units for widths and font size (e.g., em or %). 2. Which browsers and which browser versions will you support? At MIT we write code to work in the IS&T supported browsers. If you expect your site to be viewed by people outside of MIT or around the world you may need to consider older browsers. Note: IS&T supported browsers include Internet Explorer v. 7, 8, Safari v. 4 and Firefox v What is the minimum screen resolution you will support? Many people in the world may still have monitors with an 800x600 pixel screen resolution. At MIT most people probably have screen resolutions of 1024x768. This means that a page in a browser maximized to full screen WITHOUT the need for a horizontal scroll bar. Allowing for the edges of a browser called "chrome" we would use a maximum width of 760px for an 800x600 resolution or 950px for a 1024x768 screen resolution. We will write for a 1024x768 screen width.

24 Positioning using Float Creating a Float Layout This layout uses a containing block, a sixth div around the five content divs which forms what is often called a wrapper. 1. Create divs for each of the five content areas header, navbar, sidebar, main, footer. 2. Add the id attribute to name each div. 3. Arrange the divs in the correct order. 4. Type the content for the footer div. 5. Set an appropriate width for each div. (you decide) 6. Float the divs into position. 7. Keep the footer in the normal flow - #footer {clear: left} 8. Center the wrapper - #wrapper {margin-left: auto; margin-right: auto} 9. Continue formatting change #wrapper background; adjust margins within the wrapper

25 Descendant Selectors Things to know about Descendant Selectors: when a tag is located inside another tag it is called a nested tag the outer tag is called the parent tag, the inner tag is called the child multiple tags inside the parent are said to be siblings two tags right next to each other are said to be adjacent siblings In the following example the divs #first and #second are parents. The h1, paragraph, ul and li elements are children. These elements are said to be nested. <div id="first"> <h1>this is a heading 1.</h1> <p>this is the first paragraph.</p> <p>this is the second paragraph.</p> </div> <div id="second"> <ul> <li>this is a line item.</li> <li>this is a line item.</li> <li>this is a line item.</li> </ul> </div> Here the h1, h2 and paragraph elements are children of the parent div element. Here is a tree diagram of this block. body div div h1 p p ul li

26 <div id="first"> <h1>this is a heading 1.</h1> <p>this is the first paragraph.</p> <p>this is the second paragraph.</p> </div> <div id="second"> <ul> <li>this is a line item.</li> <li>this is a line item.</li> <li>this is a line item.</li> </ul> </div> CSS rule #first {color: red} #first p {color: red} #second ul li {color: red} What gets styled all text in the div "first" will be colored red all text with a <p> tag in the div "first" will be colored red all li elements - within a ul element - within the div "second" will be colored red

27 Format the Menu 1. add the menu items as an unordered list Home, Events, Research, Directory, Contact Us 2. add an a tag around each line item add a space inside the link 3. create a style for #nav ul a. list-style-type: none b. margin and padding set to 0 4. create a style for #nav a a. display: block [allows the anchor tag content to stretch to full width] b. format padding, size, font, border c. text-decoration: none [removes the underline] 5. create a contextual style for the link (default) and visited states of your anchor tag a. #nav a:link, #nav: a:visited b. format only the things which will change during the hover state - text and background color 6. create a contextual style for the hover state of your anchor tag a. #nav a:hover b. format what will change when the mouse hovers over the menu choice Pop-up Menus Pop-up menus are complex to build. They may use CSS only or a combination of CSS and JavaScript. Fortunately, there is little need to build a menu system from scratch. There are several web sites which offer full or partial solutions for pop-up menus which are free to use, sometimes requiring only attribution in a comment in your code. There are a few sources for pop-up menus worth investigating. Son of Suckerfish [an old standard second iteration of Suckerfish] Ultimate Dropdown Menus [grab the code and use free for non-profits] Just to Learn about Pop-up Menus All pop-up menu implementations set up menu content as a nested, unordered list and reformat the tags to appear as blocks. An excellent tutorial on lists and menus is located at Max Design

28 Creating a Print Style Sheet It is often desirable to create a style sheet which will be applied to a web page as it is printed. This would give the style your content more appropriately for printing and possibly remove some content from being printed at all. Here are some typical styling changes for print. change the background color to white specify font sizes in points more typical for print change to serif fonts which are easier to read on the printed page hide navigation, search bars, non-essential images so they do not print o add to style of area to hide display: hidden remove positioning and specific widths if necessary to improve the flow The process for creating a print style sheet is as follows save your current style sheet with a new name 2. make the necessary changes to styles which already exist 3. to hide elements from printing (e.g., images or divs) add the property {display: none} 4. in the head of your document add a second link tag which specifies media="print" <link href="printstyle.css" rel="stylesheet" type="text/css" media="print" /> Validating your CSS The w3c offers a validation service online which allows you to check for errors in your CSS syntax. The url for this service is You can point to a CSS file already on the web by clicking the By URI tab. Or, you can upload your CSS file or simply paste your CSS code directly into the box under the By direct input tab. If you have errors, check the line number of the CSS to troubleshoot. Question: Why is it important to validate your code?

29 Resources Books Dreamweaver 8 (or CS4 or CS5) The Missing Manual - David Sawyer McFarland, 2006, O'Reilly Media, Inc. Spring into HTML and CSS -Molly E. Holzschlag, 2005, Addison Wesley Head First HTML with CSS & XHTML - Eric Freeman and Elisabeth Freeman, 2005, O'Reilly Media, Inc. CSS The Definitive Guide - Eric A. Meyer, 2006, O'Reilly Press Eric Meyer on CSS: Mastering the Language of Web Design - Eric A. Meyer, 2002, New Riders Web Sites at MIT MIT Web Publishing Reference Pages - MIT Web Publishing - MIT DCAD - Departmental Consulting and Application Development Element K at MIT - Web Publishing Intermediate Class Resources web.mit.edu/pankin/www/resources Web Sites outside of MIT A List Apart - HTML Dog - W3C Schools - Web Monkey Lynda.com - YouTube -