How to make a full-screen layout for custom keyboard viewing in android

Question

I have a keyboard where the user can switch between two different views. According to their choice, I return the layout in onCreateInputView ()

layout = (RelativeLayout)getLayoutInflater().inflate(R.layout.activity_main, null);

return layout;

XML layout

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:background="#FFF"
    android:layout_alignParentTop="true"
    tools:context="com.main.MainActivity"  
    >

    <Button 
        android:id="@+id/tag"
        android:layout_width="150dp"
        android:layout_height="50dp"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:text="#Test"
        android:visibility="visible"
        android:singleLine="true"/>


    <ImageButton 
        android:id="@+id/popular"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:layout_toLeftOf="@+id/myCaps"
        android:src="@drawable/connection"
        android:visibility="visible"
        android:background="@null"
        android:layout_marginRight="5dp"/>


    <Button 
        android:id="@+id/myCaps"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:drawableStart="@drawable/like"
        android:visibility="visible"

        android:background="@null"/>


   <!-- <GridView

        android:id="@+id/gridView_images"
        android:layout_width="fill_parent"
        android:layout_height="150dp"
        android:layout_below="@+id/myCaps"
        android:columnWidth="80dp"
        android:numColumns="5"
        android:stretchMode="none" 
        android:layout_marginBottom="20dp"

        >

     </GridView> -->


    <com.jess.ui.TwoWayGridView
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:background="#E8E8E8"
    android:id="@+id/gridView_images"
    android:layout_width="fill_parent" 
    android:layout_height="150dp"
    app:cacheColorHint="#E8E8E8"
    android:layout_below="@+id/myCaps"
    app:columnWidth="80dp"
    app:rowHeight="80dp"
    app:numColumns="2"
    app:numRows="2"
    app:verticalSpacing="0dp"
    app:horizontalSpacing="0dp"
    app:stretchMode="none"
    app:scrollDirectionPortrait="horizontal"
    app:scrollDirectionLandscape="horizontal"
    app:gravity="center"/>

<com.jess.ui.TwoWayGridView
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:background="#E8E8E8"
    android:id="@+id/gridView_tags"
    android:layout_width="fill_parent" 
    android:layout_height="150dp"
    app:cacheColorHint="#E8E8E8"
    android:layout_below="@+id/gridView_images"
    app:columnWidth="80dp"
    app:rowHeight="80dp"
    app:numColumns="2"
    app:numRows="2"
    app:verticalSpacing="0dp"
    app:horizontalSpacing="0dp"
    app:stretchMode="none"
    app:scrollDirectionPortrait="horizontal"
    app:scrollDirectionLandscape="horizontal"
    app:gravity="center"
    android:visibility="gone"/>

<!--      <GridView -->

<!--         android:id="@+id/gridView_tags" -->
<!--         android:layout_width="fill_parent" -->
<!--         android:layout_height="150dp" -->
<!--         android:columnWidth="80dp" -->
<!--         android:layout_below="@+id/gridView_images" -->
<!--         android:numColumns="5" -->
<!--         android:stretchMode="none"  -->
<!--         android:layout_marginBottom="20dp" -->
<!--         android:visibility="gone" -->
<!--         > -->

<!--      </GridView> -->


     <EditText 
         android:id="@+id/inputText"
         android:layout_below="@+id/gridView_tags"
         android:layout_width="fill_parent"
         android:layout_height="50dp"
         android:background="@drawable/edit_textfield"
         android:hint="Message"
         android:padding="5dp"
         android:visibility="gone"/>


     <LinearLayout 
         android:id="@+id/buttons"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@+id/inputText"
         android:orientation="horizontal"
         android:visibility="gone"
         >


     <Button 
         android:id="@+id/b1"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_weight="1"
         android:text="..."
         android:textSize="10sp"
         android:singleLine="true"
        />

      <Button 
         android:id="@+id/b2"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_weight="1"
         android:text="..."
         android:textSize="10sp"
         android:singleLine="true"
        />

      <Button 
          android:id="@+id/b3"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_weight="1"
          android:text="..."
          android:textSize="10sp"
          android:singleLine="true"
          />

       <Button 
          android:id="@+id/b4"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_weight="1"
          android:text="..."
          android:textSize="12sp"
          />

      </LinearLayout>

    <!--  
    <GridView   
    android:id="@+id/gridView_keys" 
    android:layout_width="fill_parent"
    android:layout_height="150dp"
    android:layout_below="@+id/inputText"
    android:columnWidth="150dp"
    android:gravity="center"
    android:layout_centerHorizontal="true"
    android:numColumns="4"
    android:stretchMode="columnWidth"
    android:layout_marginBottom="20dp"
    android:visibility="gone"/> -->


<com.main.MyKeyboardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/keyboard1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/buttons"
    android:keyBackground="@color/background_color"
    android:keyTextColor="#000000"
    android:keyTextSize="26sp"
    android:keyPreviewLayout ="@layout/preview"
    android:background="#FFFFFF"
/>  


</RelativeLayout>

The problem is that I try to make my layout full screen on the device, it does not get full screen. At the top of the layout, the application’s layout is displayed, in which my application now opens.

What needs to be done to solve it? or is it impossible

** This keyboard is not application specific and can be opened in any application that has already been made, and also exchanges an image.