View Full Version : Text-Viewer / Virtual Scrolling

8 Apr 2014, 6:42 AM
Hello All,

I plan soon enough to build a web app that will be mostly a log parser for big log files. ExtJS seems quite nice to get a Application like UI with buttons / Layout Management / ... So I am considering to use it
I would need to implement Virtual Scrolling, or as you call it buffered renderer, but to be honest I am pretty new to ExtJS. By pretty new I mean I never used it.

I think there could be 3 Approaches for this to my opinion:
-Change Grid Style so it looks like a text editor but I think I will struggle with the text Highlighting.
-Build a Plugin based in Grid and change the render function to display text instead of table data
-Build a Plugin from scratch.

I am not sure what would be the best approach here, so I am posting this in order to get some pointers that I could start investigating.

14 Apr 2014, 11:26 PM
The effort sounds rather ambitious and I'm not convinced that fitting the grid as a text editor is the right solution. What I've done before was to use the Ace editor (http://ace.c9.io/#nav=about) and have its instance target the body of an Ext panel. That way the Ext widget allows for docked toolbars, participates in layouts, etc. and the dedicated text editor plays the part of the dedicated text editor.

15 Apr 2014, 12:29 AM
Hello Slemmon,Thanks for the pointer. I have already checked ACE Editor, but AFAIK this doesn't do Lazy loading. I will be dealing with log files up to 1Gb, so I really need to load only chunks of the file.

30 Dec 2014, 12:21 PM

Did you complete this text-viewer? I am working on building the exact same thing. A "log file viewer" for possibly huge log files. I want the content of the file to be fetched as needed (say 100 lines at a time) as the user scrolls through the text area. I also want the ability for user to filter, search, highlight and things.

What would be the best way to do this? Writing something custom will surely be best, but also the most time consuming.