1.relativeLayout布局的新属性4.2
2.相对布局练习
//==================
android:layout_alignStart
android:layout_alignEnd
android:layout_alignParentStart
android:layout_alignParentEnd
//========================
android:id = "@+id/firstView"
//============
android:layout_below = "@id/fitstView"
android:layout_aligtnEnd = "@id/fitstView"
android:layout_alignParentStart = "true"
//========
<EditText
android:id = "@+id/passwordText"
android:layout_alignParentLeft = "true"
android:layout_alignParentRight = "true"
android:hint ="password"
android:inputType = "textPassword"
/>