iOS Platform Guide

iOS Platform Guide

Introduction

Apache Cordova is a library used to create native mobile applications using Web technologies. The application is created using HTML, CSS and JavaScript and compiled for each specific platform using the platform native tools. Cordova provides a standard set of JavaScript APIs to access device features on all supported platforms. This document describes how to get started using Apache Cordova for the iOS platform.

Requirements

Install Cordova

Download Cordova

Download the latest version of PhoneGap from http://phonegap.com/download. Click on the Download icon and select cordova-x.x.x-src.zip to download to your machine. The download includes the code for all of the Apache Cordova supported platforms.

Extract Cordova

To access the code, it needs to be extracted from the archive (.zip) file:

  1. Navigate to the folder where you downloaded the code. Find the version-specific cordova-x.x.x-src.zip file.

  2. Using the Finder® app, double-click the file to extract. This creates a directory named cordova-x.x.x.

  3. Expand this folder and locate the cordova-ios.zip file and double-click to extract it.

  4. The code for iOS is within the cordova-ios directory structure.

Project Creation

Xcode projects for Cordova are created by invoking a script file via the command line. The following steps explain how to create the necessary directory structure, open and use the Terminal application to create a new project, and execute the create script.

Determine Project Location

Determine where on your system to place your application's Xcode project files. This tutorial uses ~/Documents/CordovaXY, where the 'X' and 'Y' refer the to Cordova version number.

  1. In the Finder, navigate to the Documents directory.

  2. Create a subdirectory within Documents called CordovaXY, where the 'X' and 'Y' represent the Cordova version number (23, for example). You can use a different directory name or location if you wish, but you need to remember it for subsequent steps.

Open Terminal

  1. Open the Terminal application, located by default in the Applications/Utilities folder.

  2. Use the Finder to navigate to the cordova-ios directory from the downloaded and extracted Cordova code. Highlight the bin subdirectory as shown:

    NOTE: Your listing varies depending on Cordova's version number.

  3. Drag this directory to the open the Terminal icon in the dock. This opens up a default terminal window with the path set to the bin directory.

Create New Project

Command Line Syntax

  1. Determine Required Parameters

    Three parameters are required to creating a Cordova project from the command line, in this order:

    1. project location

      This directory is where the Xcode project and application files are to be located. This tutorial uses ~/Documents/CordovaXY as the base location (with 'X' and 'Y' representing the Cordova version number) and the HelloWorld application name as the project directory. Since the command creates the final HelloWorld directory, it must not already exist.

    2. package name

      When submitting apps to the App Store, this must be the reverse domain name App ID that is created via the Apple Provisioning Portal (described in the Deploy to Device section). The Provisioning Portal is accessible once you have paid for and signed into your iOS Developer Account. Since you don't need to submit this sample app, this tutorial uses org.apache.Cordova plus the HelloWorld app name: org.apache.cordova.HelloWorld

    3. project name

      This is the name of the actual project. Most developers match the project name with the application name, so in this example it's HelloWorld.

  2. Execute the Command

    In the terminal app with bin as the current directory, enter the 3 pieces of information via the following command: ./create ~/Documents/CordovaXY/HelloWorld org.apache.cordova.HelloWorld HelloWorld

  3. Fix Common Problems

    No Developer Directory Found

    The “Error: No developer directory found at /Developer” message is displayed if the create script can not find the location of the command-line tools within Xcode. This can occur if more than one version of Xcode is installed on the system or when upgrading from older versions of Xcode. The solution is to run the xcode-select command to set the location. If you have installed Xcode in the default location the command to execute is:

        sudo /usr/bin/xcode-select -switch /Applications/Xcode.app/Contents/Developer

    See http://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/xcode-select.1.html for more information on the xcode-select command if you have installed Xcode in a different location.

Optional Features

Running the Application

Open the Project

Using the Finder app, navigate to the location where you created the project. This guide uses ~/Documents/CordovaXY/HelloWorld. Double-click the HelloWorld.xcodeproj file to open the project in Xcode.

Your screen should look similar to:

NOTE: this screen capture shows a project that was created with the name as HelloWorld23.

Deploy to the Simulator

  1. In the upper-left corner of Xcode, click on the Scheme drop-down list and select the project name, HelloWorld, as the target.

  2. Click the device section and select an iOS Simulator such as iPhone 6.0 Simulator as shown:

  3. Click the Run button in your project window's toolbar to build, deploy and run the application in the simulator.

Deploy to the Device

Requirements

There are several requirements to deploy to a device. Since this information is not related directly to Cordova, please refer to the Configuring Development and Distribution Assets section of Apple's Tools Workflow Guide for iOS.

Deployment Steps

  1. Plug your device into your Mac via the USB Cable.

  2. Select the Target and device

    1. In the upper-left corner of the Xcode window, click the Scheme drop-down list and select the project name, HelloWorld, as the target.
    2. Click the device section and select your device from the list. If your device is plugged in via the USB but not visible in the device list, click the Organizer button to determine any errors.

  3. Click the run button to build, deploy and run the application on your device.

Results

The running HelloWorld app is shown below. The Device is Ready line should be slowly pulsating.

Common Problems

Deprecation Warnings

When an application programming interface (API) is changed or replaced by another API, it is marked as deprecated. The API still works in the near term, but is eventually removed. Some of these deprecated interfaces are reflected in Apache Cordova, and Xcode issues warnings about them when you build and deploy an application. The Xcode warning about the ‘invokeString’ method concerns functionality that launches the app from a custom URL. While the mechanism to load from a custom URL has changed, this code is included to provide backwards functionality for apps created with older versions of Cordova. The sample app does not use this functionality, so these warnings can be ignored.

If you wish to remove the warnings you can remove the code that references the deprecated invokeString API:

  1. Edit the Classes/MainViewController.m file.

  2. Find and comment out the following code by surrounding it with the begin, /*, and end, */, comment characters as highlighted in the code snippet below.

    (void)webViewDidFinishLoad:(UIWebView*)theWebView
{
// only valid if ___PROJECTNAME__-Info.plist specifies a protocol to handle
/*
if (self.invokeString) {
  // this is passed before the deviceready event is fired, so you can access it in js when you receive deviceready
  NSLog(@"DEPRECATED: window.invokeString - use the window.handleOpenURL(url) function instead, which is always called when the app is launched through a custom scheme url.");
  NSString* jsString = [NSString stringWithFormat:@"var invokeString = \"%@\";", self.invokeString];
  [theWebView stringByEvaluatingJavaScriptFromString:jsString];
}
*/
// Black base color for background matches the native apps
theWebView.backgroundColor = [UIColor blackColor];


return [super webViewDidFinishLoad:theWebView];
}

  3. Press Command s to save the file.

  4. Navigate to the AppViewDelegate.m file in the Classes Folder.

  5. Comment out the following line by placing a double slash at the beginning of line 73 as shown below:

    //self.viewController.invokeString = invokeString;

  6. Press Command-s to save the file.

  7. Press Command-b to rebuild the project and eliminate the warnings.

Missing Headers

Some users have encountered compilation errors relating to missing headers. This refers to a problem in the build location and is fixed via Xcode preferences.

  1. Within the Xcode menus select Xcode → Preferences → Locations.

  2. In the Derived Data section click the Advanced button and select Unique as the _Build Location as shown:

    This is the default setting for a new Xcode install, but it may be set differently if you upgraded from an older version of Xcode.

Next Steps

Building Your Own Applications

Include Cordova

All of the code for the sample application is contained within the Xcode project's www directory, where the starting page is named index.html. Any page that invokes Cordova APIs must reference the version-specific cordova-x.x.x.js file, as shown in the sample HelloWorld application's index.html:

  <script type="text/javascript" src="cordova-x.x.x.js"></script>
  <script type="text/javascript" src="js/index.js"></script>
  <script type="text/javascript">
      app.initialize();
  </script>

Wait for deviceReady Event

When loading a page, Cordova’s deviceReady event must fire before you can access any of the platform features via the Cordova JavaScript APIs. Within the sample application this is set up within the app object found within the js/index.js file. The app.initialze() call at the bottom of the index.html file (visible in the previous code example) sets in motion the binding of events to receive and respond to the deviceReady event.

Another common way to initialize a page is to add a deviceReady event listener from the body's onload event handler as shown below:

  <head>
    <script type="text/javascript" src="cordova-x.x.x.js"></script>
    <script>
      function onLoad() {
    document.addEventListener(
      ‘deviceready’, onDeviceReady, false);
    }
    function onDeviceReady() {
      // do Something!
      // example: display a Cordova Alert
      // see docs.phonegap.com for full details
      navigator.notification.alert(
        'Cordova is ready!',       // message
        function() {//do something},  // callback
        'Congratulations',            // title
        'Done'                      // buttonName
       );
    }
    </script>
    </head>
    <body onload=”onLoad();”>
    .....

Code Your Application

Replace the sample code in the www directory of a new project with the HTML, JavaScript and CSS code for your application. The name of the initial file to load when the app is launched should be index.html (advanced users can change this if necessary). As demonstrated in the HelloWorld sample application, subdirectories within the www directory are permitted. Note that the www directory is readonly, you can not write information to this directory during app execution. If you need to store information use the Cordova File or Storage APIs.

You can use many mobile JavaScript frameworks with Cordova to create the UI and page navigation of your application. Popular ones include:

Modify Project Settings

There are many additional considerations to make your application unique. The sample HelloWorld application is set up to run in all iOS environments, iPhone, iPod, and iPad. You can design an app for a single device type by modifying the build settings within Xcode.

You should customize the application with your own icons and splash screens. The sample application includes Cordova specific images in the Apple required sizes and resolutions as examples. The Cordova Specific settings are located in the config.xml file and documented in the Cordova Project Settings Guide. Refer to the Resources section for more Apple specific information about building iOS Apps.

Resources

Apple

Some of these references are within the Apple iOS Developer Reference and require an iOS Developer License.

Apache Cordova

The PhoneGap contains all of the links below and more.

Credits

Mac®, OS X®, Apple®, Xcode®, App Store℠, iPad®, iPhone®, iPod® and Finder® are Trademarks of Apple Inc.