how to permanently override android soft keys behaviour and display through
<p>I am relatively new to android and want to create an application that permanently overrides androids basic softkey behaviour and view (for devices with soft keys).</p>

<p>Some functionalities I want to implement are changing the size of the softkeys window at the bottom, change its images, and possibly change its functionality.</p>

<p>For example, the user can set the size to of the softkey to be "large", "medium" or "small". And I can change the functionality of the back button to open say a particular application instead of going "back".</p>

<p>I'm basically looking for a high level answer as to how to do this, a basic direction of what I should read/study in order to be able to accomplish this. I realise this may require root access.</p>

<p>Please note that I want this behaviour to change not only in my application but I want the effect to exist on all applications. If this requires the application to be running atleast at the backend, that is fine.</p>

<p>After doing some decent amount of search, it seems I will have to make changes in the systemUI.apk, or possibly get its source code and modify it. Is this correct?</p>

<p>Thanks in advance.</p>
