[Android] Stop EditText Focus 取消自動跳出鍵盤

* Stop EditText from gaining focus at Activity startup
或是 Android 開發筆記 - 解決/取消 EditText 自動 focus 問題

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/mainLayout"
android:descendantFocusability="beforeDescendants"
android:focusableInTouchMode="true" >