靜宜大學資管系 楊子青 1 Working with Databases (II) 靜宜大學資管系 楊子青

靜宜大學資管系 楊子青 2 Creating a Custom TinyWebDB Service tinywebdb.htmlhttp://beta.appinventor.mit.edu/learn/reference/other/ tinywebdb.html –TinyWebDB is an App Inventor component that allows you to store data persistently in a database on the web. –By default, the TinyWebDB component stores data on a test service provided by App Inventor, This service is helpful for testing, but it is shared by all App Inventor users, and it has a limit of 1000 entries. If you use it, your data will be overwritten eventually. –For most apps you write, you'll want to create a custom web service that isn't shared with other App Inventor apps and programmers.

靜宜大學資管系 楊子青 3 To create your own web service Follow these instructions: –Download App Engine for Python at ( 之前需先下載 Python) After installing it, run the GoogleAppEngineLauncher by clicking its icon. –Download this sample code and Unzip the downloaded zip file. It is a zip file containg the source code for your custom tinywebdb web service. ( 檔案有問題，改找 appinventordb.zip) –In the GoogleAppEngineLauncher, choose File | Add Existing Application. Browse to set the Path you just unzipped. Then click the Run button. This will launch a test web service that runs on your local machine. –You can test the service by opening a browser and entering “localhost:8080” as the URL. You‘ll see the web page interface to your web service. ( 如果瀏覽器無法顯示，也沒有關係 )

靜宜大學資管系 楊子青 4 To create your own web service (Cont.) Follow these instructions: –Your app is not yet on the web. You need to upload it to Google's App Engine servers. In the GoogleAppEngineLauncher, choose Dashboard. –Enter your Google account information and you'll be taken to an App Engine dashboard. Choose Create an Application. –You'll need to specify a globally unique Application Identifier. –Provide a name to your app and click Create Application to submit. Edit the file app.yaml. –Modify the first line so that the application matches the application identifier In GoogleAppEngineLauncher, choose Deploy and follow the steps. –Test to see if your app is running on the web. In a browser, enter myapp.appspot.com, only substitute your identifier for "myapp". It’s on the web and you can access it from your App Inventor for Android app.

靜宜大學資管系 楊子青 5 To create your own web service (Cont.) Follow these instructions: –Your App Inventor apps can store and retrieve data using your new service. Just do the following: Drag in a TinyWebDB component into the Component Designer. Modify the ServiceURL property from the default to your web service. Any StoreValue operations (blocks) will store data at your service, and any GetValue operations will retrieve from your service.