react native animation , Easing.bounce force bounce only two times - react-native

Question

Is it possible to for Easing.bounce to bounce only 2 times?
And not 3 times;
Animated.timing(
this.y_translate,
{
delay: 0,
toValue: 1,
easing: Easing.bounce,
duration: 1000,
}
).start();
});

Answer 1

Short answer is no.
Long answer is to look at the docs.
You'll see that Easing.bounce is based off of this mathematical definition that has the bounce happening 4 times. You can see exactly how they do this in their example code (note the easeInBounce, easeOutBounce, and easeInOutBounce functions). If you compare this with what is in the React Native source for Easing.bounce, you'll find the same mathematical calculations.
So if you want to have a two bounce effect, you'll need to do the math yourself. For example, you can create your own Easing class with it's own bounce method. Then use it in your animation in place of Easing.bounce.
// You can also extend Easing and just define a new method (or override)
// if you want access to Easing's other methods.
class MyEasing {
/**
* Provides a two bounce effect.
*/
static bounce(t: number): number {
/* Code Goes Here */
return something;
}
}
// ... in your code ...
Animated.timing(
this.y_translate,
{
delay: 0,
toValue: 1,
easing: MyEasing.bounce,
duration: 1000,
}
).start();
});
How you do this calculation though is outside the scope of the question, so I'll leave that for your to figure out.