Follow the Bouncing Ball
Video Tutorial
Click here for a YouTube video of Lloyd building this project. The video has been optimized for viewing on an iPad.
(Note: For a "crystal clear" video, you may have to manually change the quality settings in YouTube to "720p HD" - just look for the gear symbol in the bottom right-hand corner of the YouTube window.)
I built this project solely with local variables as a help to see the difference between global and local variables.
LiveCode File for this Project
Script for the button "Bounce":
on mouseUp
hide me
put item 1 of the location of button "ball" into x
put item 2 of the location of button "ball" into y
put line 1 of field "speed" into varSpeedx
put line 2 of field "speed" into varSpeedy
repeat until the mouseclick
if x > 320 then put -1*varSpeedx into varSpeedx
if x < 0 then put -1*varSpeedx into varSpeedx
if y > 480 then put -1*varSpeedy into varSpeedy
if y < 0 then put -1*varSpeedy into varSpeedy
wait 1 millisecond
add varSpeedx to x
add varSpeedy to y
set the location of button "ball" to x, yend repeat
show me
end mouseUp