Please HELP! How can i move cursor in on-screen keyboard with external keyboard?

Hi there all. I am new in Android and i am working to make an on-screen keyboard which can be visitable via arrow(direction) keys of my external keyboard. I mean i wanna move left, right, up and down in the on-screen keyboard's UI (keys) with pressing arrow keys from my external(hardware) keyboard. The key that cursor is on should be focused, when i press an arrow key from my external keyboard the focused key should change and when i press "enter" from my external keyboard it should be operated.(written to the screen etc.) How can i make this? Is there any idea? How can i make virtual keyboard's keys visitable? It doesn't look like moving around a matrix of buttons. Please, help me.
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