Visual Basic Concepts

Element Positioning in DHTML Applications

Several features of Dynamic HTML give you detailed control over the position and behavior of elements on an HTML page. You can control where an object is placed, and work with special effects such as animation, transitions and filters, and automatic resizing.

Positioning and Animation

Positioning is the ability to place an HTML element at a specific point in a page by assigning an x- and y-coordinate and a z-plane to that element. This means you can place elements exactly where you want them and achieve special, overlapping effects by defining how elements should be stacked on top of one another.

Because the object model gives you access to styles and style sheets, you can set and change the position of an element as simply as you set and change its color. This makes it especially easy to change the position of elements based on how the user is viewing the page, or to animate the elements. For animation, all you need is to slightly modify the position of an element at some regular interval.

For More Information   For more information on positioning effects, see "Positioning" in the "Dynamic HTML" section of the Internet/Intranet/Extranet Services SDK.

Automatic Resizing and Scrolling

In a standard Visual Basic application, you have to write code that tells the system how to respond when a user resizes a form. In a Web page built with Dynamic HTML, the Web browser automatically handles the resize event and adjusts the user interface accordingly. In Dynamic HTML, percentages can be used as sizes for elements. In addition, you can anchor elements at a particular place in the flow of text. This enables a page to resize flawlessly.

In addition, you can now create bottomless, scrollable forms. Forms in Visual Basic do not scroll and have a set size. HTML pages, however, always include a scroll bar and can be considered bottomless because the user can continue scrolling as long as there are elements to view.

Filters and Transitions

Internet Explorer 4.0 enables you to specify filters and transitions using cascading style sheet, or CSS, properties. Filters are effects (such as text drop shadows) that can be applied to content on Web pages. Transitions are effects that can be applied when changing the display of an element—switching from one image to another, for example. Both transitions between pages and transitions on specific elements within a page are supported.

In addition to the set of standard filters and transitions included in Internet Explorer 4.0, the standard filters and transitions can be supplemented by additional third-party filters and transitions.

For More Information   For more information on filters and transitions, see "Filters and Transitions" in the "Dynamic HTML" section of the Internet/Intranet/Extranet Services SDK.