Android keyboard height

Hello! I need get height of Android keyboard. TouchScreenKeyboard.area.height return 0 for Android. I try to write own keyboard for android (android plugin). But I stopped on activity.findViewById(viewid) - return always null - not find view by resource id. (this need me for initialize new Keyboard:

mKeyboardView= (KeyboardView)mHostActivity.findViewById(viewid);
mKeyboardView.setKeyboard(new Keyboard(mHostActivity, layoutid));
mKeyboardView.setPreviewEnabled(false); // NOTE Do not show the preview balloons
mKeyboardView.setOnKeyboardActionListener(mOnKeyboardActionListener);
mHostActivity.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

Probably to late for the OP. But for anyone else using google then this thread over here had an answer that worked for me.

http://forum.unity3d.com/threads/keyboard-height.291038/