Support for badges from the NavigationComponent (#72)

* Support for badges from the NavigationComponent

* Add an example of using Redux to get a badge count with React Navigation

example/ReactNavigationReduxConnectedNavigationComponent.js

@@ -0,0 +1,113 @@
+import React, { Component } from 'react'
+import { connect } from 'react-redux'
+import { AppRegistry, StyleSheet, Text, View, Button } from 'react-native'
+import { NavigationComponent } from 'react-native-material-bottom-navigation'
+import { TabNavigator } from 'react-navigation'
+import Icon from 'react-native-vector-icons/MaterialIcons'
+
+
+/**
+ * Screen for first tab.
+ * You usually will have this in a separate file.
+ */
+class MoviesAndTV extends Component {
+  static navigationOptions = {
+    tabBarLabel: "Movies & TV",
+    tabBarIcon: () => <Icon size={24} name="ondemand-video" color="white" />
+  }
+
+  render() {
+    return <View><Text>Movies & TV</Text></View>
+  }
+}
+
+/**
+ * Screen for second tab.
+ * You usually will have this in a separate file.
+ */
+class Music extends Component {
+  static navigationOptions = {
+    tabBarLabel: "Music",
+    tabBarIcon: () => <Icon size={24} name="music-note" color="white" />
+  }
+
+  render() {
+    return <View><Text>Music</Text></View>
+  }
+}
+
+/**
+ * Screen for third tab.
+ * You usually will have this in a separate file.
+ */
+class Books extends Component {
+  static navigationOptions = {
+    tabBarLabel: "Books",
+    tabBarIcon: () => <Icon size={24} name="book" color="white" />
+  }
+
+  render() {
+    return <View><Text>Books</Text></View>
+  }
+}
+
+/**
+ * Component which wraps NavigationComponent and is passed additional properties which can
+ * dynamically alter the bottomNavigationOptions. For example, you could use Redux to get
+ * the unread book count, pass it into this components props, and then change the badge count.
+ */
+function UnreadBooksNavigationComponent(props) {
+  const { unreadBookCount, bottomNavigationOptions, ...rest } = props;
+  return (
+    <NavigationComponent
+      bottomNavigationOptions={{
+        ...bottomNavigationOptions,
+        tabs: {
+          ...bottomNavigationOptions.tabs,
+          Books: {
+            ...bottomNavigationOptions.tabs.Books,
+            badgeText: unreadBookCount > 0 ? "" + unreadBookCount : undefined,
+          }
+        }
+      }}
+      {...rest}
+    />
+  );
+}
+const ReduxNavigationComponent = connect(
+  (state) => ({
+    unreadBookCount: state.unreadBooks.length
+  }),
+  (dispatch) => {}
+)(UnreadBooksNavigationComponent);
+
+/**
+ * react-navigation's TabNavigator.
+ */
+const MyApp = TabNavigator({
+  MoviesAndTV: { screen: MoviesAndTV },
+  Music: { screen: Music },
+  Books: { screen: Books }
+}, {
+  tabBarComponent: ReduxNavigationComponent,
+  tabBarPosition: 'bottom',
+  tabBarOptions: {
+    bottomNavigationOptions: {
+      labelColor: 'white',
+      rippleColor: 'white',
+      tabs: {
+        MoviesAndTV: {
+          barBackgroundColor: '#37474F'
+        },
+        Music: {
+          barBackgroundColor: '#00796B'
+        },
+        Books: {
+          barBackgroundColor: '#5D4037'
+        }
+      }
+    }
+  }
+})
+
+AppRegistry.registerComponent('MyApp', () => MyApp)

lib/NavigationComponent.js

@@ -94,7 +94,11 @@ class NavigationComponent extends PureComponent<void, NCProps, void> {
             label: tabOptions.label || label,
             labelColor: tabOptions.labelColor,
             activeLabelColor: tabOptions.activeLabelColor,
-            barBackgroundColor: tabOptions.barBackgroundColor
+            barBackgroundColor: tabOptions.barBackgroundColor,
+            badgeText: tabOptions.badgeText,
+            badgeSize: tabOptions.badgeSize,
+            badgeStyle: tabOptions.badgeStyle,
+            isBadgeVisible: tabOptions.isBadgeVisible
           }
 
           return <Tab