The long trailing plant looks like a variegated Plectranthus to me. The yellow flower might be a marigold.

I think the trailing plant is Baby Sunrose. (Aka: Heartleaf Ice Plant).
The yellow are definitely Marigolds.
The peeks of violet could be Dianthus?
I couldn't guess the grass in the center, but I'd use an Aztec Grass type plant. (Or even better, something with flowers of it's own... like Society Garlic)

Here is a link that might be useful: Sunrose

this just popped back into my head ...

i will ID them for you.. very simply..

you have a hanging vine..
a vertical..

and a short impact plant ...

it doesn't matter what you use.. if you put those 3 criteria.. in a planter ...

make any sense??

this might help the newbie.. even if you already knew the formula ...

ken