A number of users asked us how to use a custom image as background for mobile app. We are working on this feature but a simple work around exists. We want to run a very simple jQuery CSS query when the mobile screen loads. First, add load event to the screen. Then, add Run Custom JavaScript action with the following code:
PhoneGap is one of the foundation technologies for Tiggr Mobile Apps Builder. Tiggr’s extensive capabilities in JavaScript customization allow developers an easy way to use the PhoneGap API to make native apps that access device features (like using the camera). In this webinar, we’ll show you how it’s done with hands-on examples and then you’ll have the chance to ask questions.
I’m sure you’ve heard about platform-as-a-service (PaaS) or cloud-based services like Google Apps Engine,CloudBees, Heruko, Engine Yard, and Cloud Foundry. All are excellent platforms that ease the process of managing, maintaining, and administering the platform on which an application you develop runs. Most tend to be focused on the hosting and managing side of the finished application. But what about a cloud-based service that enables you to build an app, and specifically a mobile app? Well, such a service already exists. The cloud-based service is called Tiggr Mobile Apps Builder.
One of the most important features in Tiggr is being able to export the app as HTML5 mobile app, Android app or iOS native app. All export features are show by clicking the big Export button:
As you noticed, there is currently no BlackBerry option. But, it turns out it’s pretty easy to get a BlackBerry native app.
Any app in Tiggr, be it for Android, iOS or BlackBerry is built first with jQuery Mobile component, HTML5, JavaScript and CSS. Then, the app is packaged as native with PhoneGap. For BlackBerry, simply export the app as HTML/CS/JS, and to build a native we are going to use PhoneGap Build.
Here are the steps:
Build an app in Tiggr (try getting started guides) and export it as HTML/CSS/JS
HTML5′s local storage is undoubtedly one of the most interesting and most talked about features in the HTML5 technology stack. Local storage is part of Web Storage specification and is supported by all modern browsers (destkop and mobile). Although local storage (or Web Storage) sounds rather sophisticated, the functionality is very easy to use. You basically get a map as storage inside the browser (available to all browser windows). You can insert, delete or read key/value pairs. That’s it. Data stored in local storage (localStorage) will be there when you close and open the browser. There is also session storage (sessionStorage). As the name implies, it will be only available as long as the browser window is open, and will be cleared when browser window is closed.
The only other thing to know is that data saved by a page is only available for a pages from the same domain. In other words, a page loaded from abc.com, doesn’t have access to data saved by page from domain xyz.com.
We are going to going to build an app that looks like the screen shot below. In fact, you can try the app here (click the image, or scan the QR code). Try it on your mobile device as well.
To build the app, I used Tiggr Mobile Apps Builder. If you are wondering why Tiggr? Well, because it’s incredibly simple and fast to create a project and build app. If you don’t have an account yet, quickly sign up here.
First build the UI by dragging and dropping jQuery Mobile components from the palette on to the phone. At any point, you can click Test to try the app in browser, or mobile browser.
You can use Tiggr to build real mobile apps without writing any JavaScript. But, for more advanced cases (like ours), you can easily write any custom JavaScript. You can even import 3rd party JavaScript libraries. In our case, we are going to create a new JavaScript file (called asset) with the following content:
// save itemfunction save(item){var size = localStorage.length+1;
localStorage.setItem('key'+ size, item);}// get storage contentfunction storage(){var output='';for(i=0; i <= localStorage.length-1; i++){
key = localStorage.key(i);
val = localStorage.getItem(key);if(i ==0){
output = val;}else{
output = output +'\n'+val;}}return output;}// clear storagefunction clear (){
localStorage.clear();}
There are three functions, one for saving a new item (save()), one for getting the current storage (storage()) and one for clearing the content (clear()). Local storage API is very simple. For example, to save an item:
localStorage.setItem('key','item');
then, to get a value from storage:
localStorage.getItem('key');
This is how the complete file looks inside Tiggr’s JavaScript editor:
The last step is to invoke JavaScript when the buttons are clicked. We also want to load storage content when the screen is loaded for the first time. Let’s work on the buttons first. To invoke JavaScript on button click, we first add click HTML event to the button:
Then we add Run Custom JavaScript action by clicking the + button:
Click on the action to enter JavaScript code. The code for Save to Local Storage button looks like this:
var item =$('[dsid="input"]').val();
save(item);var output='';
output = storage();
$('[dsid="storageContent"]').text(output);
We first find the input component using jQuery (it’s going to simpler to do that, once we introduce Tiggr JavaScript API, work in progress). Save the value from the input element, reload storage content so we can display it inside the textarea.
If you don’t know what Tiggr is, Tiggr is a Web-based mobile apps builder or a mobile RAD (Rapid Application Development) tool. It enables developers to build mobile Web and native apps very quickly. Tiggr comes with a visual editor and jQuery Mobile components. You simply drag and drop components into the phone area.
This makes it very easy to prototype and build the UI. Once you have developed the UI (which you can share and test in browser or mobile device), you define and connect to REST services. Once the service is defined, it is mapped to the UI. A service usually has inputs and outputs. Mapping means taking input from UI (such as input component) and using it as input for the service. On the other side, taking service output and mapping it back to the UI, for displaying the result. One last step is usually adding an event to invoke the service. For example, on a button click the service can be invoked. What I just described is a very easy and fast way to build mobile Web apps. There is nothing to setup or configure, just launch the Tiggr visual editor and start building.
Now, how do you get a native app? That’s where PhoneGap comes in. PhoneGap is an open source framework, it wraps your mobile Web app and gives you access to native device API. To use native features, PhoneGap provides very clean and elegant API. For example, to sound a notification beep twice, you need to call the following:
navigator.notification.beep(2);
Simple, right?
To get device information, the following code is used:
Any native mobile project in Tiggr comes configured with PhoneGap version 1.0. How do you invoke this API when building a mobile app in Tiggr? It’s very simple. Tiggr comes with Run Custom JavaScript action which can be invoked on any HTML event. Let’s take a button. When a button is clicked (click event), you add an action (Run Custom JavaScript) to invoke. That’s it. Inside the Run Custom JavaScript, you can run any custom JavaScript.
You start with a button, we will use the Vibrate button:
Add click HTML event to the button:
Add Run Custom JavaScript action:
and finally add PhoneGap JavaScript call:
navigator.notification.vibrate(1000);
Another option is to create a JavaScript file (Project > JavaScript), write all the custom code there in functions and then invoke any function via Run Custom JavaScript action.
JavaScript file:
Invoking a function from the custom JavaScript file:
Once you use native API, testing in Web browser is no longer possible. To make it super easy to test your native app, you can use Tiggr Mobile Tester. It’s a native app (Android, iOS) which lists all your mobile projects created in Tiggr. You simply tap any app and launch the native app. The app looks like this:
Like what you see? Try Tiggr Mobile Apps Builder yourself!
