add keyboard listener for IOS

src/InputToolbar.js

@@ -3,6 +3,7 @@ import React from 'react';
 import {
   StyleSheet,
   View,
+  Keyboard,
   ViewPropTypes,
   Dimensions
 } from 'react-native';
@@ -12,6 +13,38 @@ import Send from './Send';
 import Actions from './Actions';
 
 export default class InputToolbar extends React.Component {
+  constructor(props) {
+    super(props);
+
+    this.state = {
+      position: 'absolute'
+    };
+  }
+
+  componentWillMount () {
+    this.keyboardWillShowListener =
+      Keyboard.addListener('keyboardWillShow', this._keyboardWillShow);
+    this.keyboardWillHideListener =
+      Keyboard.addListener('keyboardWillHide', this._keyboardWillHide);
+  }
+
+  componentWillUnmount () {
+    this.keyboardWillShowListener.remove();
+    this.keyboardWillHideListener.remove();
+  }
+
+  _keyboardWillShow = () => {
+    this.setState({
+      position: 'relative'
+    });
+  }
+
+  _keyboardWillHide = () => {
+    this.setState({
+      position: 'absolute'
+    });
+  }
+  
   renderActions() {
     if (this.props.renderActions) {
       return this.props.renderActions(this.props);
@@ -53,7 +86,8 @@ export default class InputToolbar extends React.Component {
 
   render() {
     return (
-      <View style={[styles.container, this.props.containerStyle]}>
+      <View
+        style={[styles.container, this.props.containerStyle, { position: this.state.position }]}>
         <View style={[styles.primary, this.props.primaryStyle]}>
           {this.renderActions()}
           {this.renderComposer()}
@@ -70,7 +104,6 @@ const styles = StyleSheet.create({
     borderTopWidth: StyleSheet.hairlineWidth,
     borderTopColor: '#b2b2b2',
     backgroundColor: '#FFFFFF',
-    position: 'absolute',
     bottom: 0,
     width: Dimensions.get('window').width
   },