# rotation animation block challenges Coding challenges for the rotation animation. ## Before we get started Complete the following guided activity: * [activity](/lessons/rotation-animation/activity) At the end of the activity, your code should look like this: ```blocks let rotating = true; while (rotating) { basic.pause(20) basic.showLeds(` # . . . . . # . . . . . # . . . . . # . . . . . # `) basic.showLeds(` . . # . . . . # . . . . # . . . . # . . . . # . . `) basic.showLeds(` . . . . # . . . # . . . # . . . # . . . # . . . . `) basic.showLeds(` . . . . . . . . . . # # # # # . . . . . . . . . . `) } ``` ## Challenge 1 Now let's add to this by creating a condition for on button pressed `A` before the while loop. We will also introduce serial writeLine for the while loop and input OnButtonPressed ```blocks let rotating = true; while (rotating) { serial.writeLine("loop") basic.showLeds(` # . . . . . # . . . . . # . . . . . # . . . . . # `) basic.showLeds(` . . # . . . . # . . . . # . . . . # . . . . # . . `) basic.showLeds(` . . . . # . . . # . . . # . . . # . . . # . . . . `) basic.showLeds(` . . . . . . . . . . # # # # # . . . . . . . . . . `) } input.onButtonPressed(Button.A, () => { serial.writeLine("hello") }) ``` ## Challenge 2 Now that we have the on button pressed condition, let's make the animation stop rotating by setting the rotating global variable to false when button `A` is pressed. ```blocks let rotating = true; while (rotating) { serial.writeLine("loop") basic.showLeds(` # . . . . . # . . . . . # . . . . . # . . . . . # `) basic.showLeds(` . . # . . . . # . . . . # . . . . # . . . . # . . `) basic.showLeds(` . . . . # . . . # . . . # . . . # . . . # . . . . `) basic.showLeds(` . . . . . . . . . . # # # # # . . . . . . . . . . `) } input.onButtonPressed(Button.A, () => { serial.writeLine("hello") rotating = false }) ``` * Run the code to see the awesome rotation. ## Challenge 3 Let's also make the image rotate the opposite way when button A is pressed! We can do this with another while loop that is only executed while `not rotating`.