值不显示在视图上，但能够在控制台上打印并进入控制器，angularJs＆amp;离子的

Question

 (function() {
 'use strict';
 angular.module('myApp')
 .controller('mrSearchCtrl', function($scope, $http, $timeout) {


$scope.keyword = null;
var userToken =  JSON.parse(localStorage.getItem("userInfo"));
  $scope.SearchMrHistory = function(){

   var searchData = {
     'keyword': $scope.keyword
   };

   $http.post("url?requestToken=" + userToken.token + "&start=0&end=5", searchData)
   .success(function(searchData, status)  {
    //  alert("searched");
    for(var i=0; i < searchData.length; i++)

      $scope.patientName = searchData[i].patientName;
       console.log("Patient Name" + $scope.patientName);

能够在控制台中查看此patientName，但不在视图中，我的视图如下：

<div class="list" ng-controller="mrSearchCtrl">
  <div class="item item-input-inset">
    <label class="item-input-wrapper">
      <input placeholder="Search MR" id="SearchMrDetail" type="text" ng-model="keyword">

    </label>
    <button class="button" ng-click="SearchMrHistory()">Search</button>
          </div>
</div>
 <ion-list>
  <span ng-show="patientName">  Searched Name : {{patientName}}  </span>

NOTHING正在观看，它是空的，请帮忙。