How do I add charge jumps like in Jump King?

I've been having trouble adding charge jumps into my games, older posts either don't work or the images of events have been outdated.

I haven't played Jump King but I am guessing from videos, you hold some kind of key to jump and based on how long you hold, the jump height changes?

If that is the case, something similar I did was add an instance variable called "jumpLength" (number). Then in the event sheet I would do something like:

Key is down (Space) -> Add to jumpLength variable (dt).

Then in your jump logic, simply add jumpLength. You can increase how high the jump is by multiplying a constant instead of just adding "dt" so something like "5 * dt" for example.

Note that it would be a good idea to have another variable called "maxJumpLength" to limit how high the jump can be.

Thank you!