Add a hardwareback option to allow for the hardware back button to go back.

src/android/InAppBrowser.java

@@ -78,6 +78,7 @@ public class InAppBrowser extends CordovaPlugin {
     private static final String CLOSE_BUTTON_CAPTION = "closebuttoncaption";
     private static final String CLEAR_ALL_CACHE = "clearcache";
     private static final String CLEAR_SESSION_CACHE = "clearsessioncache";
+    private static final String HARDWARE_BACK_BUTTON = "hardwareback";
 
     private InAppBrowserDialog dialog;
     private WebView inAppWebView;
@@ -88,6 +89,7 @@ public class InAppBrowser extends CordovaPlugin {
     private String buttonLabel = "Done";
     private boolean clearAllCache= false;
     private boolean clearSessionCache=false;
+    private boolean hadwareBackButton=false;
 
     /**
      * Executes the request and returns PluginResult.
@@ -363,12 +365,28 @@ public class InAppBrowser extends CordovaPlugin {
     /**
      * Checks to see if it is possible to go back one page in history, then does so.
      */
-    private void goBack() {
+    public void goBack() {
         if (this.inAppWebView.canGoBack()) {
             this.inAppWebView.goBack();
         }
     }
 
+    /**
+     * Can the web browser go back?
+     * @return boolean
+     */
+    public boolean canGoBack() {
+        return this.inAppWebView.canGoBack();
+    }
+
+    /**
+     * Has the user set the hardware back button to go back
+     * @return boolean
+     */
+    public boolean hardwareBack() {
+        return hadwareBackButton;
+    }
+
     /**
      * Checks to see if it is possible to go forward one page in history, then does so.
      */
@@ -428,6 +446,10 @@ public class InAppBrowser extends CordovaPlugin {
             if (hidden != null) {
                 openWindowHidden = hidden.booleanValue();
             }
+            Boolean hardwareBack = features.get(HARDWARE_BACK_BUTTON);
+            if (hardwareBack != null) {
+                hadwareBackButton = hardwareBack.booleanValue();
+            }
             Boolean cache = features.get(CLEAR_ALL_CACHE);
             if (cache != null) {
                 clearAllCache = cache.booleanValue();

src/android/InAppBrowserDialog.java

@@ -48,7 +48,11 @@ public class InAppBrowserDialog extends Dialog {
         } else {
             // better to go through the in inAppBrowser
             // because it does a clean up
+            if (this.inAppBrowser.hardwareBack() && this.inAppBrowser.canGoBack()) {
+                this.inAppBrowser.goBack();
+            }  else {
                 this.inAppBrowser.closeDialog();
             }
         }
     }
+}