In > this <
thread, the user was asking about how to do a marquee in App Inventor.
Abraham Getzler has a good solution there using a Label.
This is another way to do it using a Canvas and the DrawText block.
The canvas Width is set to fill parent and the height is determined by a formula based on the Canvas FontSize.
A Clock Timer block is used to time the scrolling of the text and sliders are used to adjust the FontSize, Clock Interval and the number of pixels the text moves horizontally for each clock cycle (Pixels/Interval).
Remove the Sliders, replace them with fixed values, and this becomes a very simple project with two event blocks and a global variable!