This simple prototype demonstrates how have a container expand and collapse while moving adjacent content in sync.

This prototype is a simulation of one part of the Pandora iPhone app. I have chosen to simulate the part of the app where the user selects a Pandora radio station and then proceeds to select that station. What I have demonstrated is how how the radio station animates from a small entry on a list to a large full screen entry and vice versa. If you would like to see how I created this prototype, please watch this video tutorial here: http://docs.proto.io/videos/pandora-tutorial-part-1/

This is an expand/collapse menu example that can be created using container states.

Ski/snowboarding trip planning app.

If you need to get the Y position of a vertically scrolling container, create a text box. Then on the container scroll trigger, set a variable that evaluates the numerical callback value from the event (Y position). Then add a callback that changes the text property of the text box by reading from the variable.