WhoIsQuiz Sample Apps

A new version of the WhoIsQuiz app has been added to the Downloads page for Core 2: Brainstorming http://unitydcu.ie/ss-c2d

WhoIsQuiz_example_1.aia shows how the app would appear at the end of video 5 (users type in answers), while WhoIsQuiz_example_2.aia shows how the app would appear at the end of video 8 (welcome screen, users select answers from a list). To load either of these into App Inventor, download and save the .aia file, then use Projects -> Import project (.aia) from my computer to upload it.

Both versions include the correction to the end-of-game logic described in the Project Notes document http://unitydcu.ie/ss-c2n. If this logic correction is not applied, the app as built in the videos crashes when the last question is answered. It may be a useful exercise to have students try to debug and correct the app themselves; the ability to do so demonstrates the transition from following the instructions in the video to understanding the logic and flow of the code.

App Inventor Update

An update to MIT App Inventor was pushed out on 27 January, and users will see a pop-up screen alerting them to this on their first sign-in after that date. None of the updates described in the release notes should have an impact on existing Smart Skills apps.

If you have installed the AI2 Companion App on an Android device in order to use the WiFi or USB 'live debug' methods, it will need to be updated to use the new features in this App Inventor release. If you installed the Companion App from the Google Play store, it will update automatically; if you installed it directly to your device, you will need to manually update to version 2.40 at appinv.us/companion.

Cloud Storage: TinyWebDB

MIT App Inventor includes a TinyDB component which allows a simple database to be created on the Android device; this could be used to store a local high score in a game, for example. TinyDB is also useful for passing data between screens in a multi-screen app, as normally it's only possible to pass one value between screens.

There's also a cloud-based equivalent, TinyWebDB, which allows data to be stored online: it can therefore be shared between different apps and different devices. This could be used to store a global high score, shared with all players of a game, and updated if they beat it. It could also be used to build a rudimentary message storage and retrieval system, allowing messages to be sent from one client device to another via a central server: the basis of email or messaging.

The default cloud-based database is a shared resource, and data written to it will be overwritten at some point, depending on how many other App Inventor apps are using it.

We have therefore created a new TinyWebDB service specifically for UniTY teachers and students: it is still shared of course, but only among participating schools. Data should therefore be persistent provided (a) unique keys are used to prevent accidentally deleting or modifying someone else's data, and (b) nobody deliberately deletes or modifies data other than their own. Be warned that data stored in the database is not private!

The UniTY database can be selected by setting the ServiceURL to http://unity-dcu-tinywebdb.appspot.com/

A demo app using TinyDB and TinyWebDB has been added to the UniTY section of the app library.

Resizing images for the Brainstormer Quiz app

For those students who want to use their own images in the Who-Is-Quiz app built as part of the Core 2: Brainstormer project, it's best to resize the images before uploading them to App Inventor. Most image processing programs offer the ability to resize or scale an image: one such program is Autodesk Pixlr, which can either be downloaded and installed as a desktop app, or used online as a web app called Pixlr Express - the latter is useful if students do not have install rights on their PCs. For the quiz, a maximum image dimension (height or width) of 240 pixels should work well for most images.

Also, a reminder that the Project Notes for Core 2: Brainstormer (http://unitydcu.ie/ss-c2n) include important information about fixing a crash in the version of the app described in the videos.

Inspirational Video Example

Hi All,

The Journal.ie covered this video this morning by one of our final year students studying Journalism in DCU, Laura Horan.

The video is very simple and straightforward but the message is powerful. I would encourage you to show it to your students to inspire them for their own video ideas.

It is an excellent example to show how an honest story of someone speaking from the heart can be very moving and powerful.

Enjoy.
Darran

Near Field Communications (NFC) Demo

App Inventor supports very basic Near Field Communications (NFC) capability, allowing the reading and writing of text tags. NFC is the short range communications protocol that underlies contactless payments ('tap to pay') capabilities on credit and debit cards, as well as services like Samsung Pay that allow a phone to be used for payments. It's also used in Leap Cards, office access badges, and hotel room keycards.

An app to read and wite NFC tags has been added to the UniTY section of the App Library. Some things to consider before trying out the app:

1. NFC is not supported on Amazon Fire tablets, but is supported on many Android phones.
2. NFC tags must already be configured as Text Tags to work with this app; this can be done with an app such as NFC Tools, as most NFC tags are blank when purchased.
3. NFC tags can be purchased directly from companies such as ZipNFC or through their eBay store for under 50c each, plus postage.

App Orientation (BlueStacks)

The BlueStacks emulator opens in landscape mode every time, and can only be switched to portrait after an app is running. The sample Smart Skills apps provided at the Download link for each project have therefore been updated to set the Screen1 property ScreenOrientation to Portrait. This automatically switches BlueStacks to portrait mode when the app is launched.

This change also forces the Nox emulator to switch to portrait mode when the app is launched, however with Nox it is possible to configure the initial screen size and orientation in the Advanced Settings, which should be set to Phone and 480x800 for optimum compatibility with the apps.

This change has no effect on ARC Welder orientation, which must be set when an app is first loaded in each session, as described in the previous post.