App Inventor: Create Your Own Android Apps
Format: PDF / Kindle (mobi) / ePub
Yes, you can create your own apps for Android phones—and it's easy to do. This extraordinary book introduces App Inventor for Android, a powerful visual tool that lets anyone build apps for Android-based devices. Learn the basics of App Inventor with step-by-step instructions for more than a dozen fun projects, such as creating location-aware apps, data storage, and apps that include decision-making logic.
The second half of the book features an Inventor's manual to help you understand the fundamentals of app building and computer science. App Inventor makes an excellent textbook for beginners and experienced developers alike.
- Design games and other apps with 2D graphics and animation
- Create custom multi-media quizzes and study guides
- Create a custom tour of your city, school, or workplace
- Use an Android phone to control a LEGO® MINDSTORMS® NXT robot
- Build location-aware apps by working with your phone’s sensors
- Explore apps that incorporate information from the Web
- Learn computer science as you build your apps
displaying, Displaying the Current Location current location, recording, How the blocks work remembered location, displaying directions to, Displaying Directions to the Remembered Location remembered location, retrieving when the app launches, How the blocks work remembered location, storing persistently, How the blocks work complete app, How the blocks work components, designing, Getting Started Angle property of the OrientationSensor, Using the Orientation Sensor, Using the Roll
“joinFMDT” and branches one of two ways based on the answer. In general, if and ifelse blocks can be nested to arbitrary levels, giving you the power to program increasingly complex behaviors (see Chapter 18 for more information on conditional blocks). The message is broadcast using a foreach (within the outer then clause). The foreach loops through and sends the message to each item in the BroadcastList. As the foreach repeats, each succeeding phone number from the BroadcastList is stored in
at the Bookstore user interface shown in the Designer Table 13-1 lists all the components you’ll need to build the UI shown in Figure 13-5. Table 13-1. Component list for the “Amazon at the Bookstore” app Component type Palette group What you’ll name it Purpose Textbox Basic SearchTextBox The user enters keywords or ISBN here. HorizontalArrangement Screen Arrangements HorizontalArrangement1 Arrange the buttons in a line. Button Basic KeywordSearchButton Click to search
explain the steps of “brush your teeth” to his or her child each night, that kid might not make it to the fifth grade. It’s much more efficient to just say, “Brush your teeth,” and everyone can move on with getting to bed at a reasonable hour. Similarly, once you define the procedure distanceBetweenPoints, you can ignore the details of how it works and simply refer to the procedure’s name (or call it) when designing or coding a larger app. This type of abstraction is key to solving large
corresponding call blocks look different than those for a procedure. Compare the call to convertListToText with the call to the displayList in Figure 21-14. Figure 21-14. The call on the right returns a value and so must be plugged into something The difference is that the call convertListToText has a plug on the left. This is because when the call is executed, the procedure will run through its task and then return a value to the call block. That return value must be plugged into