Add touch slop before sending home intent from DeviceLockedInputConsumer

import android.content.Context;

import android.content.Intent;

import android.graphics.PointF;

import android.view.MotionEvent;

import android.view.ViewConfiguration;

/**

 * A dummy input consumer used when the device is still locked, e.g. from secure camera.

public class DeviceLockedInputConsumer implements InputConsumer {

    private final Context mContext;

    private final float mTouchSlopSquared;

    private final PointF mTouchDown = new PointF();

    public DeviceLockedInputConsumer(Context context) {

        mContext = context;

        float touchSlop = ViewConfiguration.get(context).getScaledTouchSlop();

        mTouchSlopSquared = touchSlop * touchSlop;

    }

    @Override

    @Override

    public void onMotionEvent(MotionEvent ev) {

        // For now, just start the home intent so user is prompted to unlock the device.

        float x = ev.getX();

        float y = ev.getY();

        if (ev.getAction() == MotionEvent.ACTION_DOWN) {

            mTouchDown.set(x, y);

        } else if (ev.getAction() == MotionEvent.ACTION_MOVE) {

            float xSquared = (x - mTouchDown.x) * (x - mTouchDown.x);

            float ySquared = (y - mTouchDown.y) * (y - mTouchDown.y);

            if (xSquared + ySquared > mTouchSlopSquared) {

                // For now, just start the home intent so user is prompted to unlock the device.

                mContext.startActivity(new Intent(Intent.ACTION_MAIN)

                        .addCategory(Intent.CATEGORY_HOME)

                        .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK));

            }

        }

    }

}