Requirements

We've established the ideal UI for our application, but how does this translate into technical requirements?

• We want line charts to show trends
• We want these charts to be able to update when they receive new data
• We want to be able to choose a date range and update charts and grids accordingly
• We want to be able to choose a data category and have grids update accordingly

Let's look at each of these in the context of Ext JS:

• Ext JS charts have area, line, scatter series, and so on, so we can plot the data in a way that allows you to visualize a trend.
• The load method of Ext.data.Store can accept an addRecords parameter, which when set to true will cause newly loaded records to be appended to the store rather than overwriting the existing data. This will allow us to provide update data to a chart.
• Ext JS provides a date field component that can be linked to a view model to filter data based on a date range.
• Grids have a reconfigure method that allows you to change the columns...