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FileReader progress

Dylan Margoczi
Ranch Hand

Joined: Jul 12, 2007
Posts: 38

I want to have a progress bar in my gui that will show the status of a file being read/written. I read/write the file one line at a time, the problem is I don't know how many lines there are to begin with so i can't make a comparison for the progress bar.

Help me....
Ernest Friedman-Hill
author and iconoclast

Joined: Jul 08, 2003
Posts: 24199

The "length()" method in will tell you the size of a file; from this you can estimate the number of lines to use for your reading progress bar.

For writing to the file, you need to come up with your own way to estimate how much data is left to write, based on your knowledge of what the data is.

[Jess in Action][AskingGoodQuestions]
Bill Cruise
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Joined: Jun 01, 2007
Posts: 148
You don't know how many lines there are, but you do know how many bytes there are in the file. Keep track of how many bytes you've read (the length of each line) as you read lines, and use the ratio to update your progress bar.
Dylan Margoczi
Ranch Hand

Joined: Jul 12, 2007
Posts: 38

Sweet sweet guys....
thats perfect

I agree. Here's the link:
subject: FileReader progress
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