Dope sheet animation-fire animation problem

Hello,

I am making a 2D game, but now I have a bit trouble with Unity dope sheet animation. To use dope sheet animation, I have to use Animator component, but when I want to manage firing animation, I don't know how to do that. For example, I have a Jump animation, and then, I have a Jump-Fire animation, but how I can change from Jump to Jump-Fire, when the Jump animtion played for about half of its length? I tried a Trigger variable to control animation, but it always play the Fire animation from begining while the Jump animation is played for about 50 percent.

Anyone get this problem? Please help me, I really don't know what to do.