activity_main.xml

activity_main.xml:

<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.wyl.wylhandler.MainActivity$PlaceholderFragment" >



    <TextView

        android:id="@+id/textViewId"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="@string/hello_world" />

	

    <Button 

        android:id="@+id/buttonId"

        android:layout_centerVertical="true"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="handler传输"

        />

</RelativeLayout>