Adapt the entire camera to a fragment

I am developing an app to query qr in a database but I am having problems with the camera I am using the ZXING library to capture the QR data and generate the query

But fragment is only adapting a part of the camera, I share the XML and the class of the camera to see if they help me.

Class

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.zxing.Result;
import me.dm7.barcodescanner.zxing.ZXingScannerView;



public class Camera extends Fragment implements ZXingScannerView.ResultHandler {
    private ZXingScannerView mScannerView;
    public static boolean mAutoFocus = false;
    public static int mCameraId = -1;

    class C03012 implements Runnable {
        C03012() {
        }

        public void run() {
            mScannerView.startCamera();
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        mScannerView = new ZXingScannerView(getActivity());
        mScannerView.setResultHandler(this);
        mScannerView.startCamera();
        mScannerView.setAutoFocus(true);
        return mScannerView;

    }

    @Override
    public void handleResult(Result rawResult) {
        mScannerView.resumeCameraPreview(this);
        String sendTxt;
        sendTxt = rawResult.toString();

        Search search = new Search();
        search.setConsult(sendTxt);
        ((MainActivity)getActivity()).recibirTexto(sendTxt);
        mScannerView.postDelayed(new C03012(),20000000);

    }

    @Override
    public void onPause() {
        super.onPause();
        mScannerView.setResultHandler(this);
        mScannerView.startCamera();
        mScannerView.setAutoFocus(true);
    }

    @Override
    public void onResume()
    {
        super.onResume();
        try {
            this.mScannerView.setAutoFocus(mAutoFocus);
            mScannerView.startCamera();
        } catch (Exception e) {
            e.printStackTrace();
            try {
                mAutoFocus = false;
                this.mScannerView.setAutoFocus(mAutoFocus);
                mScannerView.startCamera();
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
    }
    @Override
    public void onDestroy()
    {
        super.onDestroy();
        mScannerView.stopCamera();
    }

 **XML**


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

<AbsoluteLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">


    <fragment
        android:id="@+id/scanner_fragment"
        android:name="com.example.eslopezem.myapplication.Camera"
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:layout_marginBottom="@dimen/camera_layout_margin_bottom"
        android:layout_marginTop="@dimen/camera_layout_margin_top"
        android:layout_weight="1"
        android:layout_x="0dp"
        android:layout_y="0dp"
        android:maxHeight="@dimen/scannner_view_height"
        android:orientation="vertical"
        android:layout_centerInParent="true"></fragment>