Q:

Struggling with the eyedropper tool in illustrator sampling colors?

I'm trying to figure out how can I use the eyedropper tool in illustrator like you would in Photoshop? 
When I try to sample colors outside of the gradient panel/color pallet panel, the tool is not as simple as it is in Photoshop. 
I need to add the colors to the swatches panel, making sure the panel is un-docked so you can add the colors freely, the process is very annoying and time consuming, not like with Photoshop. You can sample colors at any time.
I was hoping there was a solution, maybe a setting I need to check for this or something I'm doing wrong. 
An image is attached for a better understanding

A:

Select the black object(square). 
Take Eyedropper tool. 
Click one of the other objects.

Eyedropper doesn't just copy color over to the selected object(s), it picks other properties as well, like for example text style or opacity. 
If you just want the color and nothing else, hold down Shift when you use the eyedropper tool. This probably requires you to pay attention to the stroke and fill in the toolbar. The active one is the one in front. If you have stroke currently active, it'll replace the color in that. You can toggle them active with X and switch them around with Shift+X or just use mouse clicks.
In this situation you shouldn't need to use shift because it looks like the only difference between the objects is the fill color.

