Opening MacOS X Finder Window on A Hidden Folder from Terminal

Most Unix/Linux based operating system such as Ubuntu or Mac OS X has their own method to hide a specific file or folder from a File Manager application. A file or folder with a dot character (.) at the beginning on its name normally will not be shown by a simple ls command or File Manager application except configured to do so. On a Mac OS X Finder application, files Continue reading

Install Raspbian Wheezy on Raspberry Pi SD Card Using MacOS X

Raspberry Pi is a credit card size ARM-powered mini computer which is very popular among embedded system developer and hobbyist. A vanilla Raspberry Pi is not come built-in with an operating system. The operating system for Raspberry Pi can be installed on an SD-card which is loaded during bootup process. So, to make your Raspberry Pi useful, you need to install an operating system into an SD Card, plug it Continue reading

Android: Passing ArrayList of Object Within an Intent

An intent is an object that is very useful to pass variables between activities in Android. Basic primitive data types such as Integer, String, Boolean are easy to be passed through an intent. On my previously written article on how to switch between android activities I already explained on how to pass a char sequence variable. But Android has no custom object data type that can be passed directly through an Continue reading

Tutorial: Android SQLite Database

SQLite is one of several ways that Android provide to store data. SQLite is already come with vanilla Android OS and it is very light weight to be used under mobile environment. Below is the tutorial on how to create classes to handle SQLite database operations. For the sake of simplicity, I only uses one table with only 3 columns to store cars information. The three columns are id (INT), Continue reading

Android: Simple Class For Easy Writing And Reading SharedPreferences String Value

SharedPreferences is used to store small configurations or settings data in your Android application. For example, as username or user preferences data storage. Just like variables, shared preferences can be identified by “key” string as “variable” name. Shared preferences are relatives to application. So it can not be accessed by other application directly. In the following example, I would like to store the username of logged in user so in Continue reading

Thread in Android: An Example

StrictMode is most commonly used to catch accidental disk or network access on the application’s main thread, where UI operations are received and animations take place. Keeping disk and network operations off the main thread makes for much smoother, more responsive applications. By keeping your application’s main thread (UI thread) responsive, you also prevent ANR (Application Not Responding) dialogs from being shown to users. Network requests being made on UI thread may Continue reading

Communicating PHP with Android Java using JSON

When you have several variables (data) which you would send to Android using regular text on HTTP, then JSON would become an alternative format to XML. Android has it’s own JSON parser class which able to convert text on JSON format into a JSON Object. Since version 5.2.0, PHP has it’s built in json_encode() and json_decode() function to convert an array into json string and vice versa.

Set Background Color of Android View Programmatically

While you are generating or displaying content through list views, it is sometimes you need to make a zebra-styled rows or coloring the view of row background into a custom color depending on row’s content. This snippets is applicable to any android view which is inheriting View class. So to change or modify view’s background color, it is as easy as the following code on your activity class: View v Continue reading

Android REST: HTTP GET Example

In developing a mobile application on Google Android platform often requires client-server communications. The communication itself often uses TCP/IP protocol on port 80 (HTTP) to represent a client state to a (service) server. This communication style often known as Representational State Transfer (REST). REST is a style of software architecture for distributed systems such as the World Wide Web. REST has emerged as a predominant Web service design model (wikipedia). If REST implemented in HTTP, it is often called Continue reading

Sorting Array of Objects using Ruby and Python

From my previous post, I had explained on how to sort an array consists of objects by object’s attribute using PHP. While on PHP sorting by object’s attribute requires additional function other than sorting itself, Ruby and Python has it’s own array of object sorting syntax. For example in Ruby, the following one line syntax will sort an array named population by comparing it’s objects length property (attribute) ascendingly without Continue reading