# Unit 4 Lesson 3

**URL:** <https://forum.code.org/t/unit-4-lesson-3/31406>\
**Category:** CS Principles\
**Tags:** csp-unit-5\
**Created:** [October 14, 2019, 7:46pm UTC](https://forum.code.org/t/unit-4-lesson-3/31406 "2019-10-14T19:46:57Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![k\_kuhlers](https://avatars.discourse-cdn.com/v4/letter/k/da6949/32.png) [@k\_kuhlers](https://forum.code.org/u/k_kuhlers)\
**Post date:** [October 14, 2019, 7:46pm UTC](https://forum.code.org/t/unit-4-lesson-3/31406/1 "2019-10-14T19:46:57Z")

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I have a student that wants a button click to choose a random canvas (two options). Is that possible at his point or is that coming later in Unit 5? Thanks

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**Author:** ![gjschmidt](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.code.org/gjschmidt/32/4922_2.png) [@gjschmidt](https://forum.code.org/u/gjschmidt)\
**Post date:** [October 14, 2019, 8:22pm UTC](https://forum.code.org/t/unit-4-lesson-3/31406/2 "2019-10-14T20:22:03Z")

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It might be a bit beyond Unit 3 but assuming the canvases are named _canvas1_ and _canvas2_ then this should work:

onEvent(“button1”, “click”, function(event) {  
setActiveCanvas(“canvas”+randomNumber(1, 2));  
});

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<div class="post-metadata">

**Author:** ![k\_kuhlers](https://avatars.discourse-cdn.com/v4/letter/k/da6949/32.png) [@k\_kuhlers](https://forum.code.org/u/k_kuhlers)\
**Post date:** [October 15, 2019, 2:55am UTC](https://forum.code.org/t/unit-4-lesson-3/31406/3 "2019-10-15T02:55:27Z")

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Thank you!  
Kyle Kuhlers