How to trigger a blueprint via Sequencer?

Hello there,

So I’m an animator/film-maker and I use UE4 more like a renderer than a game engine. Currently I’m working on a Star Wars Fan-Film and I created a blueprint that will make the stormtroopers shoot (Basic projectile script) and I want to make a trigger to allow me to activate the action of shooting from within Sequencer. Similar to how you can trigger/activate/deactivate particle effects in Sequencer. Is this possible?


Hello Shain,

It looks like you can add the BPs you’d like to call Functions/CustomEvents on to your sequence actor. (Just call events as you would with an events track (Be sure to right-click on the keyframe and set the Event Name))

Hope that helps!

This isn’t really something that is going to work for me. If I have let’s say 10 characters and they all are going to have that blueprint to shoot, then it will be really hard to manage I think.

I noticed I can create a custom event and tick “Call In Editor” and then it appears in the details tab of the character, but I can’t get that into Sequencer so I can’t animate it. Is there a way to get it to show up inside of Sequencer? Thanks

Okay, I got it to work by creating a “Trigger” variable and making it public, and keyframing that

Shain98-- I’d really like to know how keyframing a variable allowed you to call an event. I think I’m trying to do something similar (basically run the construction script only once as opposed to every frame). I’d be fine with just having to add a simple key to the timeline to trigger this event. Can you describe a bit more in detail what you did?

So in the blueprint I created a variable (Boolean), called “Trigger” and in the details panel of it, you can tick “Expose to cinematics”. This makes it possible to keyframe it if you add the blueprint to the sequencer. The variable is of course 0 or 1/false or true, and the game is checking what state the trigger is in with the Tick Event. (There can be only one Event Tick so I had to create 2 custom event Ticks)

Trigger is connected to Branches, and they send signal to the “Shoot” blueprint to kick off. Because I’m lazy, in my case whenever I create a key False or True, the weapon will shoot once, this way I don’t have to manually key True and then False straight away.

If I understand correctly what you want to do, and you want it to run something once, then you’ll only need one Event Tick connected to a Branch. The condition of the branch will be the Variable, and then if “True” then it will go to “DoOnce” and that will go to whatever action you want.

Hope I helped, good luck :smiley:


Wow- thanks for the speedy and detailed response! I am more of a filmmaker as well and I think our approach to sequencer is very similar.
However, I was ideally wanting a way to see the result of my custom event fire when scrubbing sequencer as opposed to having to simulate each time I playback. To be specific, I am running a blueprint which has many different pieces of clothing that can be turned on/off through variables and are set to the main character’s pose all on the construction script. Unfortunately, Sequencer’s option of re-running the construction script every frame makes it impossible to apply an animation asset in sequencer :confused:
Fwiw- this is my current solution which seems to work well enough: I setup an event track which runs an event in my blueprint which does the construction stuff. Fortunately, in Sequencer if I scrub to that keyframe it runs the event. Seems like a bit of a complicated solve, but hey it works!
Thanks again for your explanation!

I can’t get this to work in sequencer im in a different version then this post but can someone help me pls