Posts Tagged ‘Android Development’
Android: Creating a two color LED notification
Posted by Dimitri | Filed under Featured, Programming
Another programming tutorial, this time, showing how to make the built-in notification LED on a Android device continuously alternate between two colors. That said, by the time this article is being written, it’s recommended to try this code on a real Android device that has a notification LED instead of running the application on the emulator. Also, the Activity featured below has been created to work on devices with Android 2.0 or later. All code featured in this article is available for download at the end of the post.
To continuously change the colors of the LED, it’s necessary to create and initialize a Notification object that changes the LED colors and post this notification using a handle to the system’s notification service (using a instance of the NotificationManager class). The notification is then canceled, its LED color is changed and the notification is posted again and the process is repeated over and over making the colors swap back and forth. (more…)
Android: Creating a WebView dialog
Posted by Dimitri | Filed under Featured, Programming
This Android post shows how to display a WebView inside a Dialog, that renders a website to the user. Since the WebView can load just about any web page, it’s possible to provide any information to users without launching the web browser, so they never have to leave the application.
For this tutorial, all code had been developed and tested in Android 2.1, both on an emulator and on a real device. As usual, an example application with the code featured in this tutorial is available for download at the end of the post.
The first thing required to place a WebView inside a dialog is to create a custom Dialog. After that, a WebView can be added to it. The easiest way to do that is to create a new Android layout file (in Eclipse, just right click the Project folder and select New -> Android XML file). Then, add the following code: (more…)
Android: how to create a loading screen – Part 3
Posted by Dimitri | Filed under Featured, Programming
This is the third and final post of a series that explains how to code a loading screen for Android. The other two previous posts (which can be found here and here), used two distinct approaches to solve the problem of executing code on a background thread and update the progress back to the application’s UI thread. However, both of them relied on an instance of the ProgressDialog class to display the current progress. In the following paragraphs, instead of using this type of dialog, a custom View inflated from a layout XML file is going to be created to achieve that purpose.
As the other two previous posts, all the code in this article has been created and tested in Android 2.1. An example Eclipse project is available at the end of the post.
Android: how to create a loading screen – Part 2
Posted by Dimitri | Filed under Programming
This is the second tutorial from the post series that explains how to code a loading screen on Android. The first one can be found here. This post has a similar approach to the previous one, except this time, instead of using a AsyncTask to execute code on the background thread, a Thread and Handler objects are going to be used to achieve the same results.
The Activity featured below is somewhat similar to the first post, except this time, the UI rendering related functions calls will be more scattered throughout the Activity’s body. Additionally, the Runnable interface is going to be implemented multiple times in the below code. Not only that, but now it’s necessary to “kill” the thread manually after the code executes, a task that is handled automatically by the AsyncTask class (see this thread for more info).
All code has been developed and tested in Android 2.1, and is available for download at the end of the post.
Android: how to create a loading screen – Part 1
Posted by Dimitri | Filed under Programming
This is the first of three Android post in a series that explains how to code a simple loading screen that shows the progress of operation before the application’s View is loaded. This first tutorial objective is to create this loading screen in simplest way possible. The code featured in this tutorial has been developed and tested in Android 2.1, but it should work without much modification in later versions. All code featured in this tutorial is available for download at the end of the post.
Because of the nature of the Android operational system and the Activity stack, there’s no way to precisely determine the loading progress of an Activity. That’s why, in the below example, the Activity is going to be started, but instead of loading the standard View, it will load a ProgressDialog object and simulate a computationally heavy process on a background thread right on the beginning of the onCreate() method.