Login View that opens in Webview

Question

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout
    android:layout_height="wrap_content"
    android:layout_width="wrap_content"
    android:orientation="vertical"
    android:layout_centerHorizontal="true"
    android:padding="0dp">

    <ImageView
        android:layout_height="200dp"
        android:layout_width="200dp"
        android:src="@drawable/logo"
        android:layout_gravity="center"
        android:paddingBottom="30dp"/>

    <LinearLayout
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:orientation="vertical"
        android:layout_centerHorizontal="true"
        android:padding="10dp"
        android:background="@drawable/box">

        <EditText
            android:layout_height="wrap_content"
            android:ems="10"
            android:layout_width="300dp"
            android:hint="Usuário:"
            android:layout_marginBottom="10dp"
            android:shadowRadius="1.0"
            android:textColor="#3D3D3D">

        </EditText>

        <EditText
            android:layout_height="wrap_content"
            android:ems="10"
            android:layout_width="300dp"
            android:inputType="textPassword"
            android:hint="Senha:"
            android:shadowRadius="1.0"
            android:textColor="#3D3D3D">

        </EditText>

        <Button
            android:layout_height="wrap_content"
            android:text="Entrar"
            android:layout_width="match_parent"
            android:layout_marginTop="10dp"
            android:background="@drawable/botao"
            android:textColor="#FFFFFF"
            android:id="@+id/mainButton1"/>

    </LinearLayout>

</LinearLayout>

This is the login area... I have nothing in Java I only have in XML I wanted to know how to make this login area work... Placing user and login If confirmed access, open the location it is to access a webview