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Hour of Code | Dance Party: Events

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I'm Aloe Blacc.

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I'm a singer/songwriter and entertainer.

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I think computer science is really important to learn

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because computer science is the future.

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And I think it's important for people to be in control of the technology

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that is literally controlling their lives.

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To make different dance moves happen at just the right time with the music,

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you can use something called events.

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An event tells your program to listen for something to happen,

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and then react right away.

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Some examples of events are listening for a mouse click,

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an arrow button, or a tap on the screen.

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The event we're going to use now will listen for a change in the song.

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The change will trigger your dancer to do a new dance.

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Professional dancers practice their choreography by counting the beats of the song.

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In music, a measure refers to a certain number of beats.

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In most popular songs a measure is 4 beats long.

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To get your dancers to let loose, you'll need a green event block.

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This event block says after four measures.

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If you drag out a purple 'do forever' block, you can pick a dance for your dancer to do.

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Because it's under the after four measures event block,

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your dancer will wait for four measures of the song before starting their dance.

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Keep an eye on the measure counter at the top of the display area.

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Look and listen for the event that will
trigger the dance code...

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and right on cue our dancer starts going!