DHTML Window Redraw

Question:
Is there any way to control the redrawing/repainting of the open window/document? Specifically, I have to change page elements (labels, cursor style) before calling some time intensive task. I have successfully implemented changes to the cursor style but it doesn’t always change the display of the mouse cursor immediately.

Answer:
Whenever a script is evaluated (at least in Internet Explorer), the parsing agent takes over and handles all of the manipulation in a significant number of cases. For this reason, you can’t use synchronous calls to animate a screen–the script has to be interpreted first, and the result gets displayed only after the script terminates. One way around this is to perform the changing call asynchronously.

For example, suppose that I wanted to turn the cursor to an hourglass wait state before beginning some kind of a lengthy operation. The logical code to do this would be:

document.body.style.cursor="wait";for (var index=0;index<10000

This code, however, doesn't change the cursor, because the scripting engine currently has control of the action. However, you can fork it (to use an old Unix term) so that it exists on its own processing thread:

window.setTimeout("document.body.style.cursor='wait'", 0, "JavaScript")for (var index=0;index<10000

The setTimeout call essentially invokes a new thread, which will execute independently of the rest of the script. By setting the time to 0 ms, the call will be made automatically. Since the last step in the action is to set the cursor style back, the focus will return to the browser and the cursor will get updated back to its default value.

Share the Post:
Share on facebook
Share on twitter
Share on linkedin

Overview

The Latest

iOS app development

The Future of iOS App Development: Trends to Watch

When it launched in 2008, the Apple App Store only had 500 apps available. By the first quarter of 2022, the store had about 2.18 million iOS-exclusive apps. Average monthly app releases for the platform reached 34,000 in the first half of 2022, indicating rapid growth in iOS app development.

microsoft careers

Top Careers at Microsoft

Microsoft has gained its position as one of the top companies in the world, and Microsoft careers are flourishing. This multinational company is efficiently developing popular software and computers with other consumer electronics. It is a dream come true for so many people to acquire a high paid, high-prestige job

your company's audio

4 Areas of Your Company Where Your Audio Really Matters

Your company probably relies on audio more than you realize. Whether you’re creating a spoken text message to a colleague or giving a speech, you want your audio to shine. Otherwise, you could cause avoidable friction points and potentially hurt your brand reputation. For example, let’s say you create a