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Working with Frames <frame src="document2.html" /> <frame src="document3.html" /> </frameset> </html> This example defines a frameset with three horizontal frames of equal height (see Figure 14.10). The contents of document1.html are displayed in the first frame, the contents of document2.html in the second frame, and the contents of document3.html in the third frame. Output Figure 14.10. You use the <frame> tag to define the contents of each frame. [View full size image] Tip When you're creating frameset documents, you might find it helpful to indent the <frame> tags so that they're separated from the <frameset> tags in your HTML document. This has no effect on the appearance of the resulting web pages, but it does tend to make the HTML source easier to read. file:///G|/1/0672328860/ch14lev1sec3.html (6 von 7) [19.12.2006 13:49:38] Working with Frames The <noframes> Tag What happens if a browser that doesn't support frames navigates to a frameset document? Nothing. You get a blank page. Fortunately, there's a way around this problem. A special tag block called <noframes> enables you to include additional HTML code as part of the frameset document. The code you enclose within the <noframes> element isn't displayed in frames- compatible browsers, but it's displayed in browsers that don't support frames. The <noframes> tag takes the following form: <html> <head> <title>Frameset with No Frames Content</title> </head> <frameset> your frameset goes here. <noframes> Include any text, hyperlinks, and tags you want to here. </noframes> </frameset> </html> Using the frames' content and tags inside <noframes>, you can create pages that work well with both kinds of browsers. Later today, you'll add some <noframes> content to a frameset. Note The way the <noframes> tag works is actually kind of interesting. It works because web browsers are designed to ignore tags that they don't understand. So, browsers that don't support frames ignore the <frameset> and <frame> tags. They also ignore the <noframes> tag and just display whatever is inside it. Browsers that do support frames know to render the frames and ignore the text inside the <noframes> tag. file:///G|/1/0672328860/ch14lev1sec3.html (7 von 7) [19.12.2006 13:49:38] Changing Frame Borders Changing Frame Borders Notice that all the frames in today's lesson have thick borders separating them. There are a number of attributes that can be set to control the appearance of frame borders or prevent them from appearing altogether. Start with the <frame> tag. By using two attributes, bordercolor and frameborder, you can turn borders on and off and specify their color. You can assign bordercolor any valid color value, either as a name or a hexadecimal triplet. frameborder takes two possible values: 1 (to display borders) or 0 (to turn off the display of borders). Note If you turn off the border, frames-compatible browsers won't display its default three- dimensional border. However, a space will still be left for the border. HTML 4.01 currently lists only the frameborder attribute. The bordercolor attribute qualifies as an extension. For example, the following code adds a deep red border (defined by #cc3333) around the middle frame in the frameset: <html> <head> <title>The frame Tag</title> </head> <frameset rows="*,*,*"> <frame src="document1.html"> <frame frameborder="1" bordercolor="#cc3333" src="document2.html"> <frame src="document3.html"> </frameset> </html> Although HTML 4.01 doesn't provide either of these attributes for the <frameset> tag, you can use both of them to define default values for the entire frameset in current browsers. Of course, there's room for confusion when colored borders are defined. In the following frameset definition, a conflict arises because the two frames share a single common border, but each frame is defined to have a different border color with the bordercolor attribute: <html> <head> <title>Conflicting Borders</title> </head> <frameset frameborder="0" rows="*,*,*"> <frame frameborder="1" bordercolor="yellow" src="document1.html"> <frame bordercolor="#cc3333" src="document2.html"> <frame src="document3.html"> file:///G|/1/0672328860/ch14lev1sec4.html (1 von 3) [19.12.2006 13:49:39] Changing Frame Borders </frameset> </html> In addition, the frameset is defined as having no borders, but the first frame is supposed to have a border. How do you resolve this problem? You can apply three simple rules: ● Attributes in the outermost frameset have the lowest priority. ● Attributes are overridden by attributes in a nested <frameset> tag. ● Any bordercolor attribute in the current frame overrides previous ones in <frameset> tags. Additional Attributes Table 14.1 shows a few extra attributes for the <frame> tag. These attributes can give you additional control over how the user interacts with your frames. Other attributes control margins or spacing between frames and whether scrollbars appear when required. Table 14.1. Control Attributes for the <frame> Tag Attribute Value Description frameborder 1 Displays borders around each frame (default). frameborder 0 Creates borderless frames. longdesc URL Specifies a URL that provides a longer description of the contents of the frameset. Primarily used with nonvisual browsers. marginheight pixels To adjust the margin that appears above and below a document within a frame, set marginheight to the number indicated by pixels. marginwidth pixels The marginwidth attribute enables you to adjust the margin on the left and right sides of a frame to the number indicated by pixels. name string Assigns a name to the frame for targeting purposes. noresize By default, the users can move the position of borders around each frame on the current screen by grabbing the borders and moving them with the mouse. To lock the borders of a frame and prevent them from being moved, use the noresize attribute. scrolling auto (Default) If the content of a frame takes up more space than the area available, frames-compatible browsers automatically add scrollbars to either the right side or the bottom of the frame so that the users can scroll through the document. scrolling no Setting the value of scrolling to no disables the use of scrollbars for the current frame. (Note that if you do this but the document contains more text than can fit inside the frame, users won't be able to scroll the additional text into view.) scrolling yes If you set scrolling to yes, scrollbars are included in the frame even if they aren't required. file:///G|/1/0672328860/ch14lev1sec4.html (2 von 3) [19.12.2006 13:49:39] Changing Frame Borders src URL Specifies the URL of the initial source document that appears in a frame when the frameset first opens in the browser. file:///G|/1/0672328860/ch14lev1sec4.html (3 von 3) [19.12.2006 13:49:39] Creating Complex Framesets Creating Complex Framesets The framesets you've learned about so far are the most basic types of frames that can be displayed. In day-to-day use, however, you'll rarely use these basic frame designs. On all but the simplest sites, you'll most likely want to use more complex framesets. Therefore, to help you understand the possible combinations of frames, links, images, and documents that can be used by a website, this section will explore complex framesets. Task: Exercise 14.2. Creating the Content Pages for Your Frameset Most commonly, framesets provide navigation bars that keep navigational elements in view as the user scrolls through the contents of the document. By far, the most common place to present the navigation bars is on the left side of the browser window. Each time the visitor clicks a link in the left navigation frame, the content in the main frame displays the selected page. The (very silly) frameset that you'll create in this exercise demonstrates this technique. Although it's not a really practical example, it's simple, fun, and demonstrates the very same techniques you would use for a navigation bar. When you design a web page that uses frames, you normally design the frameset before you go through all the trouble of designing the content that goes into it. That's because you'll want to know how big your frames are going to be before you start designing graphics and other page content to put into them. I'm doing things a little backward here, but for good reason. It may help you to better understand how things fit together if you see real content in the frames as you design the frameset. For this reason, I'll have you design the content first. The following content pages don't include any of the frameset tags discussed so far. There are eight pages in all, but I promise that I'll keep the code for these pages really brief. Ready? Tip When you lay out the basic structure of a frameset, you don't normally want to be bothered with details such as the actual contents of the frames. However, your frameset won't be displayed properly when it's loaded into a frames- compatible browser for testing unless you define <frame> tags that include valid documents. If you want to design a frameset before you create the content, you can create a small empty HTML document called dummy.html and use it for all your frame testing. The frameset that you'll create in Exercises 14.3 through 14.7 consists of three frames. The layout of the frameset will be as shown in Figure 14.11. The frameset page loads first and instructs the browser to divide the browser window into three frames. Next, it loads the three pages that appear in the top, left, and main frames. Finally, if a user browses to the frameset without a frames-compatible browser, an alternative page will appear. file:///G|/1/0672328860/ch14lev1sec5.html (1 von 14) [19.12.2006 13:49:41] Creating Complex Framesets Figure 14.11. You'll create a frameset that consists of three frames: top, left, and main. [View full size image] The top frame always displays the same web pageaway.html. The choices.html page that appears in the frame on the left side contains a list of links to six different pages named reason1.html through reason6.html. Each of these six pages will load into the main frame on the bottom-right portion of the frameset. Start with the page displayed in the top frame. This page will always appear in the frameset. Here you can include any information you want to display permanently as visitors browse through your site. Real-world examples for the content of this frame include the name of your website, a site logo, a link to your email address, or other similar content. Type in the following code and save it to your hard drive as away.html: <html> <head> <title>I'm Away from My Desk Because</title> </head> <body bgcolor="#cc6600" text="#000000"> <h3>I'm Away from My Desk, because </h3> </body> </html> Figure 14.12 shows this page. file:///G|/1/0672328860/ch14lev1sec5.html (2 von 14) [19.12.2006 13:49:41] Creating Complex Framesets Figure 14.12. The top frame in the frameset. Next, you'll create the left frame in the frameset. On real websites, this is typically the frame used for text or image navigation links that take your visitors to several different key pages on your site. For example, a personal site might have a navigation bar that takes its visitors to a home page, a guest book, a links page, and other sections of interest. A corporate or business site could contain links for products, customer support, frequently asked questions, employment opportunities, and so on. The contents page in the following example works exactly the same way that a realworld navigation bar does. When the appropriate link is selected, it displays one of the six pages in the main frame of the frameset. The contents page contains links to six pages, reason1.html through reason6.html, which you'll create next. After you enter the following code into a new page, save it to your hard drive in the same directory as the first page and name it choice.html: Input <html> <head> <title>Reason I'm Out</title> </head> <body bgcolor="#006699" text="#ffcc66" link="#ffffff" vlink="#66ccff" alink="#ff6666"> <p>Select a reason:</p> <hr /> <p><a href="reason1.html">Reason 1</a></p> <p><a href="reason2.html">Reason 2</a></p> <p><a href="reason3.html">Reason 3</a></p> <p><a href="reason4.html">Reason 4</a></p> <p><a href="reason5.html">Reason 5</a></p> <p><a href="reason6.html">Reason 6</a></p> </body> </html> Your page should look as shown in Figure 14.13 when you open it in a browser. file:///G|/1/0672328860/ch14lev1sec5.html (3 von 14) [19.12.2006 13:49:41] Creating Complex Framesets Figure 14.13. The left frame in the frameset. Now you need to create the six pages that will appear in the main frame when the visitor selects one of the links in the contents frame. The main frame is designed to display pages that normally you would display in a full browser window. However, if you're going to display your pages in a frameset that has a left navigation bar, you'll have to account for the reduced size of the frame in your design. To keep the page examples relatively easy, I've given them all the same basic appearance. This means that the code for all of these pages is pretty much the same. The only items that change from page to page are the following: ● The title of the page. ● The description of my current mood. ● The text that describes what each image means. To create the first of the six pages that will appear in the main frame, type the following code into a new page and save it as reason1.html: Input <html> <head> <title>Reason 1 - Forgot My Lunch</title> </head> <body bgcolor="#ffffff"> <h2><img src="uhoh.jpg" width="275" height="275" align="left">I forgot my lunch at home.</h2> </body> </html> file:///G|/1/0672328860/ch14lev1sec5.html (4 von 14) [19.12.2006 13:49:41] Creating Complex Framesets Figure 14.14 shows what this page should look like in a browser. Output Figure 14.14. The first of the six pages that appear in the main frame. You code the remaining five pages for the main frame similarly. Modify the code you just created to build the second of the six main pages. The only differences from the previous code ( reason1.html) are shown with a gray background. Save the new page as reason2.html. The complete code appears as follows: <html> <head> <title>Reason 2 - By the Water Cooler</title> </head> <body bgcolor="#ffffff"> <h2><img src="flirty.jpg" width="275" height="275" align="left">I'm flirting by the water cooler.</h2> </body> </html> For the third page, modify the code again and save it as reason3.html. The complete code appears as follows: <html> <head> <title>Reason 3 - Don't Ask!</title> </head> <body bgcolor="#ffffff"> <h2><img src="grumpy.jpg" width="275" height="275" align="left">None of your business!</h2> </body> </html> Here's the fourth page (reason4.html): file:///G|/1/0672328860/ch14lev1sec5.html (5 von 14) [19.12.2006 13:49:41] . The top frame always displays the same web pageaway .html. The choices .html page that appears in the frame on the left side contains a list of links to six different pages named reason1 .html through. the frameset. Primarily used with nonvisual browsers. marginheight pixels To adjust the margin that appears above and below a document within a frame, set marginheight to the number indicated. the three pages that appear in the top, left, and main frames. Finally, if a user browses to the frameset without a frames-compatible browser, an alternative page will appear. file:///G|/1/0672328860/ch14lev1sec5.html
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