Allow to pass autofocus prop

BarcodeScanner.js

@@ -1,5 +1,6 @@
 'use strict';
 
+import React from 'react';
 import { Component, PropTypes} from 'react';
 import {
   requireNativeComponent,
@@ -12,7 +13,6 @@ import Viewfinder from './Viewfinder';
 class BarcodeScannerView extends Component {
   constructor(props) {
     super(props);
-
     this.onChange = this.onChange.bind(this);
   }
 
@@ -57,6 +57,7 @@ BarcodeScannerView.propTypes = {
   showLoadingIndicator: PropTypes.bool,
   showViewFinder: PropTypes.bool,
   torchMode: PropTypes.string,
+  autoFocus: PropTypes.string,
   viewFinderBackgroundColor: PropTypes.string,
   viewFinderBorderColor: PropTypes.string,
   viewFinderBorderWidth: PropTypes.number,

android/src/main/java/com/eguma/barcodescanner/BarcodeScannerManager.java

@@ -14,6 +14,7 @@ public class BarcodeScannerManager extends ViewGroupManager<BarcodeScannerView>
     private static final String REACT_CLASS = "RNBarcodeScannerView";
 
     private static final String DEFAULT_TORCH_MODE = "off";
+    private static final String DEFAULT_FOCUS_MODE = "on";
     private static final String DEFAULT_CAMERA_TYPE = "back";
 
     private BarcodeScannerView mScannerView;
@@ -38,12 +39,20 @@ public void setTorchMode(BarcodeScannerView view, @Nullable String torchMode) {
         }
     }
 
+    @ReactProp(name = "autoFocus")
+    public void setAutoFocus(BarcodeScannerView view, @Nullable String autoFocus) {
+        if (autoFocus != null) {
+            view.setFocus(autoFocus.equals("on"));
+        }
+    }
+
     @Override
     public BarcodeScannerView createViewInstance(ThemedReactContext context) {
         context.addLifecycleEventListener(this);
         mScannerView = new BarcodeScannerView(context);
         mScannerView.setCameraType(DEFAULT_CAMERA_TYPE);
         mScannerView.setFlash(DEFAULT_TORCH_MODE.equals("on"));
+        mScannerView.setFocus(DEFAULT_FOCUS_MODE.equals("on"));
         mScannerViewVisible = true;
         return mScannerView;
     }

android/src/main/java/com/eguma/barcodescanner/BarcodeScannerView.java

@@ -49,6 +49,10 @@ public void setFlash(boolean flag) {
         mPreview.setFlash(flag);
     }
 
+    public void setFocus(boolean flag) {
+        mPreview.setAutoFocus(flag);
+    }
+
     public void stopCamera() {
         mPreview.stopCamera();
     }