建立TimePicker

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context="com.robert.sample13.MainActivity$PlaceholderFragment" >

    <TimePicker

        android:id="@+id/timePicker"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignParentTop="true"

        android:layout_centerHorizontal="true"/>

   

    <Button

        android:id="@+id/btnSet"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_alignParentLeft="true"

        android:layout_alignParentRight="true"

        android:layout_below="@id/timePicker"

        android:layout_marginTop="29dp"

        android:text="i am all set!"

        android:onClick="btnClick"/>

</RelativeLayout>