Editable javascript chart - interactively resize bars or pie sections

I need a library or a framework plugin that can draw charts that can be modified real-time by resizing part of the chart itself. Is there such thing?

I plan to use it for adjusting the chart values. Mostly for controlling amount allocati开发者_StackOverflow中文版on.

For example. You have 4 hours and you have 5 distinct types of tasks. I want the user to be able to allocate time for each task and see visually what's the impact on the available time.

I think Visually Editable Charts of Fusion Charts is what you are looking for.

We use various charts from http://code.google.com/apis/chart/ for our web app, and it works great.

The chart are loaded once, and refreshed, each time the user change a value, with new data through their Javascript API in real-time.

gRaphael should be the most popular:

http://g.raphaeljs.com/

I can recommend HighCharts:

http://www.highcharts.com/

Found a few options: http://jamesalvarez.co.uk/uncategorized/draggable-piechart-js-class and http://www.shodor.org/interactivate/activities/PieChart/. The first one looks the most promising.