[android help] How to listen for soft keys in android?

I want to know how we can listen for the soft keys in android. In the above figure i want to listen for down arrow( i have marked it in red colour, the key one which is used to hide the keyboard). I have tried to get it action through menu options, viewconfiguration class etc. But it is not useful. Is there any method, listeners or any callback event to track this button. Please let me know your suggestions and thoughts. Any help in this regard is highly appreciable

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