Creating tables
Using CSS boxes as webpage layout
Here's how:
Creating tables
Tables are very useful in the presentation of data. The following are the html tags to be used to create a basic table:
Single-column table:
<table width="400" border="1" cellspacing="2" cellpadding="4">
<tr><td>row 1 data</td></tr>
<tr><td>row 2 data</td></tr>
</table>
Type the above in your mywebpage.html within the body tags, save and refresh your browser. That's the table on the web. Referring to the above html codes, width refers to the width of the whole table (you may also use pixel here like "800"), border is the outside line or outline of the table, cellspacing is the space between the cells, cells are the area where the data are located, cellpadding is the space between border and cells. You may change the values of these table attributes or properties based on your preference or requirement.
Though the above table html codes are still working, W3C.org requires the table properties or attributes be defined in the style sheets or CSS. Using CSS, the above table properties could be presented as follows:
Within style tags in the head:
.type1 {
width: 400px;
padding: 4px;
margin: 2px;
}
.border {
border: 1px solid #000;
}
Then, within the body tags:
<table class="type1 border">
<tr><td>row 1 data</td></tr>
<tr><td>row 2 data</td></tr>
</table>
Looking at the codes, "type1" is preceded by dot (.), meaning it is a class selector. For the next type of table properties or attributes, you may label it as type2, then type3 and so on or with other names you prefer. "border" is also a class selector and "border: 1px solid #000" is the thickness (1px), border type (solid) and color (#00f) of the border. There are more discussions of CSS in "Creating CSS boxes as web page layout" and in "Using CSS in styling your web pages"
If you want to try the above, then type the codes within the style and body tags as noted, save it and refresh your browser. It must be the same as the first one.
Now, let's make a 2-column or multi-column table:
<table width="400" border="1" cellspacing="2" cellpadding="4">
<tr><td>row 1 data 1</td>
<td>row 1 data 2</td></tr>
<tr><td>row 2 data 1</td>
<td>row 2 data 2</td></tr>
</table>
Type the above in your mywebpage.html within the body tags, save and refresh your browser. That's the 2-column table on the web. To add a column, just insert <td></td> after </td>. 1 <td></td> is one column, 1 <tr></tr> is one row and 1 <table></table> is one table.
Now, lets make a table with 1 main heading and 3 subheadings:
<table width="400" border="1" cellspacing="2" cellpadding="4">
<tr><td colspan="3">Main Heading</td></tr>
<tr><td>Subheading 1</td>
<td>Subheading 2</td>
<td>Subheading 3</td></tr>
<tr><td>row 1 data 1</td>
<td>row 1 data 2</td>
<td>row 1 data 3</td></tr>
<tr><td>row 2 data 1</td>
<td>row 2 data 2</td>
<td>row 2 data 3</td></tr>
</table>
Type the above in your mywebpage.html within the body tags, save and refresh your browser. See? Yes, just use colspan to merge the columns. To merge 2 columns, use colspan="2" and for 3 columns, use colspan="3" and so on.
If you want to merge rows, use rowspan instead of colspan. See this example:
<table width="400" border="1" cellspacing="2" cellpadding="4">
<tr><td rowspan="2">merge row data</td>
<td>row 1 data 2</td></tr>
<tr><td>row 2 data 2</td></tr>
</table>
Now, type the above in your mywebpage.html within the body tags, save and refresh your browser. Now, you see that 2 rows in your first column were merged.
Try creating your own table using different values to familiarize yourself in manipulating tables.
Creating CSS boxes for web page layout
Before, tables are being used as layout of a web page. So, the header, right bars, left bars, main content areas and footer are inside of a table. This slows down the loading of the page as the browser will have to complete first the table before it will display the content. Your visitor may have already left before your page could be displayed. If you prefer to use table as your layout, you have to avoid using big tables. You better use small tables to allow the browser display your page little by little but faster.
Though table could still be used, W3C requires CSS boxes to be used for layout instead of tables due to the issue of accessibility. CSS boxes load faster than tables. These could be controlled within the style sheets that could be within the head tags or in separate CSS file. The most critical part in css boxes is the positioning. So, I'll explain to you the positioning properties of these boxes, based on my experience:
position: absolute - You have to define the x-axis and y-axis as point of reference of the corner of the box. x-axis is either left or right and y-axis is either top or bottom. You have to define also the width or the left and right margin or padding of the box. The box is not affected by the preceding or subsequent boxes. Likewise, the boxes preceding or following the boxes that are positioned as absolute are also not affected.
float: left or right - You need to fix the width. You also need to select if left or right. The box will lean on the side you selected. It will lean on the box preceding it if there is enough space for it. This is affected by the other boxes except for the absolutely positioned boxes.
no position or position: static or fixed - This follows the normal flow. This is also affected by the other boxes except for the absolutely positioned ones. You need to define the width or the left and right margin.
Now, see the illustration below that will create 5 boxes, namely: headerbox, leftbox, centerbox, rightbox and footerbox. These are liquid boxes, which automatically adjust in width when the display window size of the computer is changed:
<style type="text/css">
body {
text-align: center;
margin: 1px;
}
#headerbox {
width: 100%;
height: 15%;
background-color: #9cf;
border: 1px solid #00f;
padding: 0px 0px 0px 0px;
margin: 0px 0px 0px 0px;
}
#rightbox {
float: right;
width: 20%;
margin-top: 5px;
text-align: center;
background-color: #cff;
border: 1px solid #00f;
height: 100%;
}
#leftbox {
float: left;
margin-top: 5px;
width: 20%;
text-align: center;
background-color: #cff;
border: 1px solid #00f;
height: 100%;
}
#centerbox {
width: 99%;
margin-top: 5px;
text-align: center;
background-color: #cff;
border: 1px solid #00f;
height: 100%;
}
#footerbox {
width: 100%;
text-align: center;
height: 15%;
vertical-align: middle;
margin-top: 5px;
background-color: #9cf;
border: 1px solid #00f;
}
</style>
</head>
<body>
<div id="headerbox">HEADERBOX content area</div>
<div id="leftbox">LEFTBOX content area</div>
<div id="rightbox">RIGHTBOX content area</div>
<div id="centerbox">CENTERBOX content area</div>
<div id="footerbox">FOOTERBOX content area</div>
</body>
First, you type the above html codes to you mywebpage.html within the head, style and body tags as noted in the above. Then, save it and refresh your browser or open the file with your browser. Are you seeing the headerbox on the top, the leftbox, rightbox and centerbox in the middle and footerbox at the bottom? Try to change the width of your browser window. See? The width of the boxes are also adjusting and that is excellent as your page will auto-adjust depending on the browser window size of your visitors! That is because I used %s in defining the width of boxes.
Now, let me explain the above codes for creating boxes as your layout.
headerbox - preceded with #, meaning it is an id selector and could be used only once per page; float: left means the box will lean on the left if fit; width: 100% means the box is 100% of the browser window and that is the reason why it is liquid; height: 15% means the box is 15% of the browser window; text-align: center is the alignment of the objects or characters inside the box; background-color: #9cf is the color of the space within the box; border: 1px solid #00f is same as discussed in Creating Tables.
rightbox - same explanations in the above except for the float: right which means the box will lean on the right and margin-top: 5px is the distance from the bottom line of the box above (headerbox).
leftbox - same explanations in the above.
centerbox - same explanations in the above except that it has no position defined, meaning it will follow the normal. It will fit itself based on the available space. This will be its 100% or full size. More than this limit will distort the box alignment.
footerbox - same explanations in the above except for the vertical-align: middle, which means that the objects or characters inside the box will be vertically-aligned in the middle.
Try changing the values of the values of the css boxes above, then save. Refresh your browser and familiarize yourself with the effect of each change. Please note, however that there may be minor differences if the above css boxes are displayed with browsers other than internet explorer like firefox and opera.
Continue with Part 3.
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