Разработка родного приложения для iOS с Ionic

-    <nav class="navbar navbar-fixed-top navbar-default" role="navigation">
-        <!-- lots of HTML here -->
-    </nav>
-
-    <div class="container">
-        <div class="alert alert-danger" ng-show="error">{{error}}</div>
-        <div ng-view></div>
-    </div>
+    <ion-nav-bar class="bar-positive nav-title-slide-ios7"></ion-nav-bar>
+    <ion-nav-view animation="slide-left-right">
+        <div class="alert alert-danger" ng-show="error">{{error}}</div>
+    </ion-nav-view>
+    <ion-footer-bar class="bar-dark" ng-show="user">
+        <button class="button button-assertive" ng-click="logout()">
+            Logout
+        </button>
+    </ion-footer-bar>

4. Измените ваши шаблоны на использование <ion-view> и <ion-content>.

После переноса маршрутов и работы базовой навигации вам необходимо изменить шаблоны, чтобы использовать <ion-view> и <ion-content>. Вот разница с самой сложной страницы в приложении.

-<div style="float: right">
-   <a href="#!/create" class="btn btn-default" ng-show="hasRole('ROLE_ADMIN')">Create</a>
-</div>
-<div class="page-header">
-   <h3>News</h3>
-</div>
+<ion-view title="News">
+    <ion-content>
+        <ion-nav-buttons side="left">
+            <div class="buttons" ng-show="hasRole('ROLE_ADMIN')">
+                <button class="button button-icon icon ion-ios7-minus-outline"
+                        ng-click="data.showDelete = !data.showDelete"></button>
+            </div>
+        </ion-nav-buttons>
+        <ion-nav-buttons side="right">
+            <a href="#/create" class="button button-icon icon ion-ios7-plus-outline"
+               ng-show="hasRole('ROLE_ADMIN')"></a>
+        </ion-nav-buttons>
 
-<div ng-repeat="newsEntry in newsEntries">
-   <hr />
-   <div class="pull-right">
-       <a ng-click="deleteEntry(newsEntry)" class="btn btn-xs btn-default" ng-show="hasRole('ROLE_ADMIN')">Remove</a>
-       <a href="#!/edit/{{newsEntry.id}}" class="btn btn-xs btn-default" ng-show="hasRole('ROLE_ADMIN')">Edit</a>
-   </div>
-   <h4>{{newsEntry.date | date}}</h4>
-   <p>{{newsEntry.content}}</p>
-</div>
-<hr />
+        <ion-list show-delete="data.showDelete" on-delete="deleteEntry(item)"
+                  option-buttons="itemButtons" can-swipe="hasRole('ROLE_ADMIN')">
+            <ion-item ng-repeat="newsEntry in newsEntries" item="newsEntry">
+                <h4>{{newsEntry.date | date}}</h4>
+                <p>{{newsEntry.content}}</p>
+            </ion-item>
+        </ion-list>
+    </ion-content>
+</ion-view>

Я перешел на использование <ion-list> с кнопками delete / options , поэтому потребовались некоторые дополнительные изменения JavaScript.

-function IndexController($scope, NewsService) {
+function IndexController($scope, $state, NewsService) {
 
    $scope.newsEntries = NewsService.query();
 
+     $scope.data = {
+         showDelete: false
+     };
+
    $scope.deleteEntry = function(newsEntry) {
         newsEntry.$remove(function() {
              $scope.newsEntries = NewsService.query();
         });
    };
+
+     $scope.itemButtons = [{
+         text: 'Edit',
+         type: 'button-assertive',
+         onTap: function (item) {
+              $state.go('edit', {id: item.id});
+         }
+     }];
}

Screenshots

After making all these changes, the app looks pretty good in Chrome.

Tips and Tricks

In additional to figuring out how to use Ionic, I discovered a few other tidbits along the way. First of all, we had a different default color for the header. Since Ionic uses generic color names (e.g. light, stable, positive, calm), I found it easy to change the default value for «positive» and then continue to use their class names.

Modifying CSS variable colors
To modify the base color for «positive», I cloned the source, and modified scss/_variables.scss.

$light: #fff !default;
$stable: #f8f8f8 !default;
-$positive: #4a87ee !default;
+$positive: #589199 !default;
$calm: #43cee6 !default;
$balanced: #66cc33 !default;
$energized: #f0b840 !default;

After making this change, I ran «grunt» and copied dist/css/ionic.css into our project.

iOS Native Integration
Our app uses a similar token-based authentication mechanism as x-auth-security, except its backed by Crowd. However, since users won’t be logging directly into the Ionic app, we added the «else» clause in app.js to allow a token to be passed in via URL. We also allowed the backend API path to be overridden.

/* Try getting valid user from cookie or go to login page */
var originalPath = $location.path();
$location.path("/login");
var user = $cookieStore.get('user');
 
if (user !== undefined) {
    $rootScope.user = user;
    $http.defaults.headers.common[xAuthTokenHeaderName] = user.token;
    $location.path(originalPath);
} else {
    // token passed in from native app
    var authToken = $location.search().token;
    if (authToken) {
        $http.defaults.headers.common['X-Auth-Token'] = authToken;
    }
}
 
// allow overriding the base API path
$rootScope.apiPath = '/api/v1.0';
if ($location.search().apiPath) {
    $rootScope.apiPath = $location.search().apiPath;
}

By adding this logic, the iOS app can pull up any particular page in a webview and let the Ionic app talk to the API. Here’s what the Objective-C code looks like:

NSString *versionNumber = @"v1.0";
NSString *apiPath = @"https://server.com/api/";
NSString *authToken = [TemporaryDataStore sharedInstance].authToken;
// webapp is a symbolic link to the Ionic app, created with Angular Seed
NSString *htmlFilePath = [[NSBundle mainBundle] pathForResource:@"index" ofType:@"html" inDirectory:@"webapp/app"];
 
// Note: We need to do it this way because 'fileURLWithPath:' would encode the '#' to '%23" which breaks the html page
NSURL *htmlFileURL = [NSURL fileURLWithPath:htmlFilePath];
 
NSString *webappURLPath = [NSString stringWithFormat:@"%@#/news?apiPath=%@%@&token=%@",
                           htmlFileURL.absoluteString, apiPath, versionNumber, authToken];
 
// Now convert the string to a URL (doesn't seem to encode the '#' this way)
NSURL *webappURL = [NSURL URLWithString:webappURLPath];
[super updateWithURL:webappURL];

We also had to write some logic to navigate back to the native app. We used a custom URL scheme to do this, and the Ionic app simply called it. To override the default back button, I added an «ng-controller» attribute to <ion-nav-bar> and added a custom back button.

<ion-nav-bar class="bar-positive nav-title-slide-ios7" ng-controller="NavController">
    <ion-nav-back-button class="button-icon" ng-click="goBack()">
        <i class="ion-arrow-left-c"></i>
    </ion-nav-back-button>
</ion-nav-bar>

To detect if the app was loaded by iOS (vs. a browser, which we tested in), we used the following logic:

// set native app indicator
if (document.location.toString().indexOf('appName.app') > -1) {
    $rootScope.isNative = true;
}

Our Ionic app has three entry points, defined by «stateName1», «stateName2» and «stateName3» in this example. The code for our NavController handles navigating back normally (when in a browser) or back to the native app. The «appName» reference below is a 3-letter acronym we used for our app.

.controller('NavController', function($scope, $ionicNavBarDelegate, $state) {
    $scope.goBack = function() {
        if ($scope.isNative && backToNative($state)) {
            location.href='appName-ios://back';
        } else {
            $ionicNavBarDelegate.back();
        }
    };
 
    function backToNative($state) {
        var entryPoints = ['stateName1', 'stateName2', 'stateName3'];
        return entryPoints.some(function (entry) {
            return $state.current === $state.get(entry);
        });
    }
})

Summary

I’ve enjoyed working with Ionic over the last month. The biggest change I’ve had to make to our AngularJS app has been to integrate ui-router. Apart from this, the JavaScript didn’t change much. However, the HTML had to change quite a bit. As far as CSS is concerned, I found myself tweaking things to fit our designs, but less so than I did with Bootstrap. When I’ve run into issues with Ionic, the community has been very helpful on their forum. It’s the first forum I’ve used that’s powered by Discourse, and I dig it.

You can find the source from this article in my boot-ionic project. Clone it and run «mvn spring-boot:run», then open http://localhost:8080.

If you’re looking to create a native app using HTML5 technologies, I highly recommend you take a look at Ionic. We’re glad we did. Angular 2.0 will target mobile apps and Ionic is already making them look pretty damn good.