tags | projects | |||
---|---|---|---|---|
|
|
This guide walks you through the process of consuming a simple Sencha Touch client that consumes a Spring MVC-based RESTful web service.
What you’ll build
You will build a Sencha Touch client that consumes a Spring-based RESTful web service. Specifically, the client will consume the service created in Building a RESTful Web Service with CORS.
The Sencha Touch client will be accessed by opening the index.html
file in
your browser, and will consume the service accepting requests at:
http://rest-service.guides.spring.io/greeting
The service will respond with a JSON representation of a greeting:
{"id":1,"content":"Hello, World!"}
The client will render the ID and content into the DOM.
You can customize the greeting with an optional query string in the url:
http://localhost:8080/?User
The code will send a parameter to the REST endpoint and render a custom greeting into the DOM.
What you’ll need
-
About 15 minutes
-
A favorite text editor
-
A modern web browser (mobile or desktop)
-
An internet connection
Create an Ext model
First, create an Ext model named GreetingModel
. Place this model
in the app/model
directory. This is the default location for
Sencha models and will allow Sencha’s loader to find it.
public/app/model/GreetingModel.js
link:complete/public/app/model/GreetingModel.js[]
GreetingModel
extends Ext.data.Model
and defines two fields:
'id' and 'content'.
Create a view
Sencha’s Ext.Panel
can be used as a simple view. This file
should also be placed in Sencha’s default location for views:
public/app/view/GreetingView.js
link:complete/public/app/view/GreetingView.js[]
The contents of the view are defined by the template described in
the tpl
config option. The tokens delineated by the curly braces
in the template (e.g. {id}
), will be replaced by the model fields
when the view is rendered.
Create an Ext store
Next, create an Ext store that will load the model.
public/app/store/GreetingStore.js
link:complete/public/app/store/GreetingStore.js[]
The store extends Ext.data.Store
and references our GreetingModel
model. To instruct the store to use the REST proxy,
we configure it with a proxy definition object with type:"rest"
and
then point it at our REST endpoint url.
To customize the greeting, create a beforeload
listener that sets
an extra parameter on the proxy’s url.
Create an Ext application
Next, create an Ext.app.Application
object using Sencha’s Ext.application
shortcut function:
public/hello.js
link:complete/public/hello.js[]
The application object automatically resolves the location of the models,
views, and stores if you follow Sencha’s default directory conventions.
You must assign the application a namespace by providing the name
parameter. You must also specify the model, view, and store in the
models
, views
, and stores
arrays so that Sencha’s loader can
find and fetch those files.
Add a launch
callback. This is where the application will be composed after
all of the files have loaded. Inside this callback, create an instance
of the view and an instance of the store. Configure the store to
autoload so it will immediately fetch the model at the endpoint url.
Add a load listener to move the fetched data into the view. Ext automatically wraps the data in an array, but the view only needs the first record.
For easier debugging, enable caching by setting the Ext Loader’s
disableCaching
option to false
.
Create the application page
Finally, create an index.html
file and add the following HTML:
public/index.html
link:complete/public/index.html[]
The first script
element loads Sencha Touch from Sencha’s CDN. The second
script loads the application object.
Run the client
To run the client, you’ll need to serve it from a web server to your browser. The Spring Boot CLI (Command Line Interface) includes an embedded Tomcat server, which offers a simple approach to serving web content. See Building an Application with Spring Boot for more information about installing and using the CLI.
In order to serve static content from Spring Boot’s embedded Tomcat server, you’ll also need to create a minimal amount of web application code so that Spring Boot knows to start Tomcat. The following app.groovy
script is sufficient for letting Spring Boot know that you want to run Tomcat:
app.groovy
link:complete/app.groovy[]
You can now run the app using the Spring Boot CLI:
spring run app.groovy
Once the app starts, open http://localhost:8080 in your browser, where you see:
The ID value will increment each time you refresh the page.
Summary
Congratulations! You’ve just developed a Sencha client that consumes a Spring-based RESTful web service.