The world we live in revolves around technology and as a growing computer scientist it is imperative that we adapt with the times. I use applications on my phone daily and I never really questioned how they worked. They just did the job required of them and I moved on with my day. But eventually I began to wonder what went into making these programs that are so engrained into my every day routine and decided to make my own. My adventure with Android programming was not devoid of hurdles, but it was incredibly rewarding. For an absolute beginner the Android site was extremely daunting and it took me some time to understand how to program UI elements and why an xml file appeared every time I made a new activity. I was not familiar with front end development and it all seemed so mysterious. How did this stuff work?  Eventually, thanks to stackoverflow and other open source websites, I took a deep dive into Android app development and found that I really loved it. 

I want to share everything I have learned with you here, so take a look at the links below and feel free to ask any questions.

Projects

CheerGram

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CheerGram is an Android Application that allows users to anonymously enter their moods at various locations. When a mood is entered the latitude longitude coordinates of the user, a string representation of the mood, date, time, and other settings values are recorded. Users can share their moods with my server or save them locally on the phone. Users can view other user’s moods on a map and send positive messages, called CheerGrams, to specific areas by tapping and holding on a that area on one of the maps. Using CheerGram as a platform for collecting the emotions of people from across the globe, I intend to look for patterns and also see if the emotions can be impacted with anonymous motivational messages, called CheerGrams. For more information about the application itself please visit cheergramapp.com.

Below you can download the app and read the paper I wrote on this project:

ZombeeWatch App

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I met Professor Petkovic from San Francisco State University during my sophomore year. During our first meeting he introduced me to a citizen science project, called ZombeeWatch, where they want ordinary citizens to collect photos and samples of infected bees. He suggested that I write an app to help this data collection process. He gave me incredible guidance and taught me the importance of user experience and seamless design. 

Tutorials

In the process of developing these two applications, I learned a wide variety of Android specific details. 

Communicating Values Between Multiple Activities

Sending Values

  1. Create an Intent object.
  2. Use the method putExtra() to attach the variable and value you want to send.
  3. Start the intent.
Below is an example of all three steps and the bottom right shows all the different types of values you can send between activities.

Receiving Values

  1. Get the intent
  2. Get the value sent by opening the intent and getting the value using getExtra() method.

Customizing Rounded Buttons

  1. Create a new xml file and name it "round_button"
  2. Place it in the res folder under "drawable_hdpi"
  3. Write the following xml code in "round_button" (bottom left)
  4. Now go to the button you want to customize and set "round_button" as its background. (bottom right)

Copying a File from One Computer to Another

  1. Open terminal
  2. scp (fileyouwanttocopy) (username)@(ipaddress):(absolutepath)/(filename). "scp" means "secure copy"
  3. if you want to copy all the files in a directory use the same line above except with "scp-r" which means "secure copy recursive" so it will copy everything in the designated directory.

Deploying a WAR file

  1. Right click on the eclipse project 
  2. Press "export".
  3. Chose "Web" and export as war file.
  4. Save to whatever folder you want.
  5. copy the file from your computer to another using the tutorial above and put it in the war directory of your server.

Upcoming Tutorials

When I get more time, I intend to develop some step by step tutorials for the various aspects of Android that I have learned including:
  • Taking photos
  • Displaying the shrinked down photo on the small screen of the phone
  • How to use various widgets: text boxes, lists, checkable lists, buttons, spinners etc. 
  • How to use the location sensors in the phone (GPS)
  • "Import R" error