How to enable keyboard in Android widget

Question

in the xml file I wrote:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_alignRight="@id/tray_opener" >
    <EditText
        android:id="@+id/search_box"
        android:layout_width="25sp"
        android:layout_height="25sp"
        android:inputType="textUri"/>
</LinearLayout>

and in java main activity I wrote:

EditText msearchword = (EditText) mPlayerButtonsLayout.findViewById(R.id.search_box);

Developed Application Result is in the following link but the keyboard doesn't pops up.