set layout component to center

here in above screen, i have two linear layouts, one for two TextView and two EditText and other layout for Three Button as shown in figure,

Now I want to set these two layouts as below:

1) The first layout is required to set at the center of the screen

2) The all buttons or second layout have to be set on the bottom of screen

So I want to ask how i can do this.

My XML file is

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height开发者_运维问答="fill_parent" 
    android:orientation="vertical"
    android:background="#000044">
    <ScrollView android:id="@+id/scrollView1" android:layout_height="wrap_content" android:layout_width="match_parent">
        <LinearLayout android:id="@+id/linearLayout1" android:layout_width="match_parent" android:orientation="vertical" android:layout_height="wrap_content" android:layout_gravity="center">
            <TextView android:text="Login Phone" style="@style/TextStyle.Default" android:id="@+id/loginphone"></TextView>
            <EditText android:layout_height="wrap_content" android:id="@+id/login" android:layout_width="match_parent" android:text="" android:inputType="number" android:numeric="integer" android:phoneNumber="true"></EditText>
            <TextView android:text="Mobile Pin" android:id="@+id/mobilepin" style="@style/TextStyle.Default"></TextView>
            <EditText android:layout_height="wrap_content" android:id="@+id/pin" android:inputType="number" android:numeric="integer" android:layout_width="match_parent" android:text="" android:password="true"></EditText>
        </LinearLayout>
    </ScrollView>
    <LinearLayout android:id="@+id/linearLayout2" android:layout_height="match_parent" android:layout_gravity="bottom" android:layout_width="fill_parent" android:orientation="horizontal" android:gravity="bottom">
        <Button android:id="@+id/preference" android:text="Preferences" android:layout_weight="1" android:layout_height="wrap_content" android:layout_width="fill_parent"></Button>
        <Button android:id="@+id/loginbutton" android:text="Login" android:layout_weight="1" android:layout_height="wrap_content" android:layout_width="fill_parent"></Button>
        <Button android:id="@+id/exit" android:text="Exit" android:layout_weight="1" android:layout_height="wrap_content" android:layout_width="fill_parent"></Button>
    </LinearLayout>    

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#000044">
    <ScrollView
        android:id="@+id/scrollView1"
        android:layout_height="0dip"
        android:layout_width="fill_parent"
        android:layout_weight="1">
        <LinearLayout
            android:id="@+id/linearLayout1"
            android:orientation="vertical"
            android:layout_gravity="center"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content">
            <TextView
                android:text="Login Phone"
                android:layout_height="wrap_content"
                android:layout_width="fill_parent"
                android:id="@+id/loginphone" />
            <EditText
                android:id="@+id/login"
                android:layout_height="wrap_content"
                android:layout_width="fill_parent"
                android:inputType="number"
                android:numeric="integer"
                android:phoneNumber="true" />
            <TextView
                android:text="Mobile Pin"
                android:layout_height="wrap_content"
                android:layout_width="fill_parent"
                android:id="@+id/mobilepin" />
            <EditText
                android:id="@+id/pin"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:inputType="number"
                android:numeric="integer"
                android:password="true" />
        </LinearLayout>
    </ScrollView>
    <LinearLayout
        android:id="@+id/linearLayout2"
        android:orientation="horizontal"
        android:layout_height="wrap_content"
        android:layout_width="fill_parent">
        <Button
            android:id="@+id/preference"
            android:text="Preferences"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:layout_width="fill_parent" />
        <Button
            android:id="@+id/loginbutton"
            android:text="Login"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:layout_width="fill_parent" />
        <Button
            android:id="@+id/exit"
            android:text="Exit"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:layout_width="fill_parent" />
    </LinearLayout>
</LinearLayout>

change the wrapper layout to a RelativeLayout.

Set the button layout to android:layout_alignParentBottom="true"set the textview layout android:layout_centerInParent="true"

Use the parent layout is the Relative Layout and add your two linear layout inside that relative layout with the property for the center layout android:layout_centerInParent="true" and for button layout android:layout_alignParentBottom="true".

Is is what you wanted?

    <ScrollView
        android:id="@+id/scrollView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <LinearLayout
            android:id="@+id/linearLayout1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:orientation="vertical" >

            <TextView
                android:id="@+id/loginphone"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Login Phone" >
            </TextView>

            <EditText
                android:id="@+id/login"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:inputType="number"
                android:numeric="integer"
                android:phoneNumber="true"
                android:text="" >
            </EditText>

            <TextView
                android:id="@+id/mobilepin"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Mobile Pin" >
            </TextView>

            <EditText
                android:id="@+id/pin"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:inputType="number"
                android:numeric="integer"
                android:password="true"
                android:text="" >
            </EditText>
        </LinearLayout>
    </ScrollView>

    <LinearLayout
        android:id="@+id/linearLayout2"
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_gravity="bottom"
        android:gravity="bottom"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/preference"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Preferences" >
        </Button>

        <Button
            android:id="@+id/loginbutton"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Login" >
        </Button>

        <Button
            android:id="@+id/exit"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Exit" >
        </Button>
    </LinearLayout>

</LinearLayout>