Posts Tagged ‘Android’

Posts that contains tutorials and information about Google’s OS, Android.

Android: Creating a button to load images from a remote server

Click here to read Android: Creating a button to load images from a remote server

This is a follow up to the post published two days ago that explained how to load images into a View’s Canvas from different sources. Differently from the last post, I will explain how to load images from a remote server after the View has been loaded and rendered on the screen. Also, this post features how to download an image after pressing a button.

So, let’s get to it. The first thing the reader might be thinking is that we just need to create a button and place the code that downloads the image inside it. It’s not as simple as that, due to these problems: (more…)

Android: loading images from a remote sever, SD card and from the Resources folder

Click here to read Android: loading images from a remote sever, SD card and from the Resources folder

As stated on the title, this post will explain how to load a image from 3 different sources: the SD card, from a remote server and from the Resources folder. Since the methods and code used to load these images from these sources are different from one another, this post is going to be divided into three different parts, one for each location.

Select one of the following links to go to a specific part of the post: (more…)

Android: touchscreen ‘swipe’ movement detection

Click here to read Android: touchscreen ‘swipe’ movement detection

This post explains how to code a simple swipe screen movement detection that can be used to control characters and other objects on an Android game or any other application.

All this code is written inside the View class, so open it up and let’s get to it. The first thing we will have to do is to create four different variables: one pair will store where the screen was touched, and the other one will be used to store the difference between the location where the screen has been pressed and where the screen has been released. Create this variables and assign zero to all of then, like this: (more…)

Android Manifest File for a Game

Click here to read Android Manifest File for a Game

Android was designed to see every application as a collection of Activities united by intents. It also relies on the Activity stack to determine what Activity will be launched after the user finishes it by pressing the ‘back’ button. While the stack system is helpful for users and for some applications, this default behavior isn’t a necessarily a good thing for games.

That is mainly because of two things: a game use a lot of hardware resources from the device that runs it, meaning that having other activities in the same stack as the game Activity can have an impact on its performance. And the stack default behavior could lead to multiple instances of the same game running in the same stack.

(more…)

Android: Changing the ‘back’ button behaviour

Click here to read Android: Changing the ‘back’ button behaviour

Sometimes, when programming Android applications, there is the need to assign another behavior for the ‘Back’ button that isn’t the default one. Although not recommended, there are some cases that changing the ‘Back’ button behavior is necessary, such as to avoid accidentally finishing the current Activity.

For example, a text editor, should confirm if the user really wants to quit without saving the current changes, or a game, that check if it is the player’s intention to forfeit the current game session.

So, to start changing the ‘Back’ button, behavior, you need to override the onKeyDown() method and than check if the desired button has been pressed: (more…)