Posts Tagged ‘Programming’

Programming related posts.

Android: how to rotate a View element

Click here to read Android: how to rotate a View element

Another Android programming tutorial, this time, explaining how to rotate a View element using two distinct approaches. Not only that, but this post also presents a brief explanation on the advantages and disadvantages of each approach. The code featured here has been tested on both the emulator and on a real device running Android 2.1 . Before going any further, please bear in mind that from Android 3.0 (API level 11), a setRotation() method has been added to the View class, therefore, it should be used instead of the code described in this article, which focuses on lower level APIs.

The first and perhaps most direct method of rotating a View element is to create a class that inherits from a View widget that needs to be rotated, for example, the TextView or the Button. Then, inside this class, the onDraw() method must be overridden. (more…)

Android: rendering a path with a Bitmap fill

Click here to read Android: rendering a path with a Bitmap fill

This Android tutorial shows how to render a Path that is filled by a Bitmap and displays stroke in a different color. It also explains how to manipulate the texture coordinates to make it independent of the position of the path, just like a mask, but without using any of the PorterDuff rendering modes. The code featured in this code was created and tested on Android 2.1, both on a real and at an emulated device.

Here’s a video of the example application in action:

If you can’t play the video, don’t worry: there is a screenshot of the application at the bottom of this post.


Unity: Making a simple audio visualization

Click here to read Unity: Making a simple audio visualization

As stated in the title, this Unity programming tutorial shows how to create a simple audio visualizer. This post focuses on explaining the necessary requirements in obtaining the audio data from the current music being played, and how to process this data to create a audio visualization. It won’t have detailed explanations on how to create a specific effect for an audio visualization. The code featured below and the example project were created and tested in Unity 3.5.2 .

For this post, the audio spectrum data will be displayed as a line using a LineRenderer component and will also feature some cubes that will fall from the top of the waveform, much like the little white bars above the spectrum found on the Windows Media Player “Bars” visualization. However, this visualization will be 3D and not 2D and will render a waveform and not bars.

To achieve that, a script and the following elements will be required: (more…)

Unity: Creating GUI transitions

Click here to read Unity: Creating GUI transitions

This Unity scripting tutorial shows how to manipulate the GUI system origin to create an animated transition, so you can make your GUI’s look more interesting. To keep things simple, this post shows how to create an horizontal transition between two Text Areas using a couple of buttons. All code featured below is available for download at the end of the post.

To achieve an animated transition, the origin of the GUI system must be manipulated. This is done by changing the elements of the matrix that sets the rendering reference point of the GUI elements. Conveniently, Unity allows us to do that by manipulating the GUI.matrix values. So, the script requires a Matrix4x4 object. Also, to make the code more readable, a Vector3 is going to be created, also making it easier to translate the GUI system origin. Here’s the script:

Android: Creating a two color LED notification

Click here to read Android: Creating a two color LED notification

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…)