Spinners display a list of selectable items.
When first displayed, the Spinner only shows the currently selected item. Touching the Spinner displays the full list of items that the user can choose from.
Our tutorial will show you how to use a Spinner to display a list of images that the user can choose from.
Our tutorial app creates a table containing text views, text fields and a button.
There is no XML layout file as we do everything programmatically.
A Toast message displays the input after the user has filled in the text fields and pressed the button.
Our tutorial app shows you how to use intents and intent filters in your apps.
Here’s a quick overview of what we’ll cover. We’ll show you how to:
Intents are messages that you can pass around between your app components. You can also send them to components in other apps. This enables you to create powerful applications where you can use other app’s components to perform tasks for you, such as playing music, sending email, and taking pictures.
Here are some of the things that you can do with intents:
The Android System also uses intents to signal changes such as low battery, incoming sms messages and phone calls. You can listen for these intent messages in your apps. You can also use intents to pass data.
You can use alarms to trigger events at any time even if your app is not running.
Device sleeping on the job? Here’s how you can manage the device awake state
You can schedule work to be done. Problem is, nothing will happen if the CPU is sleeping!
The solution is to use a wake lock to prevent the CPU from sleeping while it’s doing your work.
You may also want to keep the screen from turning off. Read on and we’ll show you how…
Here’s the third part of the Volley tutorial.
This is where we show you how to use Volley to download images and display them in a GridView.
Here’s the second part of the Volley tutorial.
This is where we show you how to use Volley to download images and display them in a ListView.
Volley is an HTTP Library that makes networking for Android easy. It’s developed by Google and is free to use in your apps.
This is what Volley can do for you:
Volley is not suitable for large downloads or streaming (Volley holds all responses in memory during parsing so large downloads will use a lot of memory).
You should use the DownloadManager for large downloads.
We’re going to be using Volley to download images for display in a list and grid.