I’ve been working on my first Phonegap project together with a friend the last week or so. He’s been developing most of the app for Android and Eclipse, and my job is to make sure it runs smoothly in iOS. It contains in-apps and some other goodies that I will post about later.
Hide buttons
Since everything in Phonegap is a UIWebView, I needed a way to get rid of the silly previous, next and done buttons when focusing my keyboard. This uses private API:s so it will make your app rejected if you submit with this code.
The solution is to modify your AppDelegate.m to something like this:
Remove and add focus on keyboard
When bringing a keyboard in and out, use the following to remove focus from it
I use Testflight to coordinate pre-releases of software I develop for the iOS platform. Testflight is an amazing tool and I’m surprised Apple hasn’t bought the company yet. You simply create a group of people, send out invites and have them register their devices with Testflight. Unfortunately, the provisioning profile in the iOS ecosystem is a huge clusterf*ck, so you have to manually and not to mention painfully add these identifiers to your provisioning profile in the Apple Developer Portal.
When the profile is updated with the correct devices, you upload the .IPA to Testflight and add some release notes and hit send. The people participating in your beta release will then get an email that they can download a new version.
Testflight and Corona SDK
At work, we use the Corona SDK to develop multi platform games. Corona Labs describes their product as follows:
Corona SDK is the leading mobile development framework. Build high-quality apps and games for iOS, Android, Kindle Fire and Nook in record time.
It works remarkably well, not too much problems and it’s easy to deploy. Anyway, to integrate Corona SDK and Testflight you need to do a couple of things:
Build your software and generate the application and it’s zip file
Create a new folder called ‘Payload’ and move the application file into it
Compress that file and change its extension to .ipa instead of .zip
Upload the IPA to Testflight
Flurry
Flurry’s error log
Flurry is a great tool for gathering statistics, I’ve used it in all applications I’ve created for iOS and made sure its been used on Android as well. One of the best features for me as a developer is the fact that I get access to the crash reports (see the picture below).
-- Import library and initialize with personal application key
require "analytics"
analytics.init( "YOUR_APP_KEY" )
-- Log event ID
analytics.logEvent( "Event ID" )
One thing I sometimes wish I would’ve implemented earlier in the project, is a log inside the app. The log should save the current state and the roadmap with the relevant server/client calls that took them there. It should also include the option to send this log to the developer.
Evernote’s log
Evernote has implemented this very neat and it could be of tremendous help when debugging the communication between the server and the clients.
The universe of the Game of Life is a two-dimensional grid of square cells, each of which is in one of two possible states, dead or alive. Each cell interacts with its eight neighbors, those cells that are horizontally, vertically, or diagonally adjacent. At each unit of time the following transitions occur:
Any living cell with fewer than two living neighbors dies, as if by under-population.
Any living cell with two or three living neighbors lives on to the next generation.
Any living cell with more than three living neighbors dies, as if by overcrowding.
Any dead cell with exactly three living neighbors becomes alive, as if by reproduction.
For an assignment at school, my classmate Jonatan and I were to implement this in Erlang.
Demonstration
This video demonstrates the finished game and two examples called a pulsar and a glider.
Source code
First off, here is the main program. If you would like some more information before seeing the code keep scrolling.
Data representation
The input to our program is represented as a list of {X,Y} tuples containing coordinates. Our internal data is represented as a single list using the indices of the list as a one-dimensional representation of the grid. This was chosen over representing the game and its input as multi-dimensional arrays for simplicity.
Note: the worst random access time of a list compared to an array is negligible as random access is only required once during the setup.
Each cell contains information about its coordinate, current state (dead or alive), list of its neighbors, and information about them such as number of living neighbors.
Synchronization
To keep our game in sync and avoid race conditions we use a “master” process to notify all cells when a new unit of time (tic) begins. Each cell responds by sending its current state to all of its neighbors then waits for its neighbors to send their current state. When all current states have been collected the new cell state is updated and drawn. This avoids synchronization issues by making sure all processes start at roughly the same time.
