Keep track of when columns change
This app shows how to use change columns. Change columns are useful for keeping track of how many changes have happened to a row and when they happened. Try changing the Color and Decimal value to see a demo.
Also see: tablet mode & fullscreen mode
How we built this app
Take a look at the columns in the spreadsheet. We made a Color and Decimal column, and then created a handful of other columns to track different changes to them. Last Change is a ChangeTimestamp column. ChangeTimestamp column definitions allow you to set which columns to monitor (ChangeColumns) and which values to monitor (ChangeValues). For the Last Change column, we haven't set either of these properties, so it will record a timestamp when Color or Decimal changes. Last Color Change is also a ChangeTimestamp, but it has ChangeColumns set to Color. This means it will only change when the Color value is changed. Last Change To Red sets ChangeColumns to Color and ChangeValues to Red. That means that it will only record a timestamp when the Color changes to Red. Finally, Change Counter is a ChangeCounter type column that just counts the number of times any value changes in the row.
This is a preview of the data sets used in the app.
This is a high-level model of both the data entities and the UI elements in the app.