~Proceedings ICMCISMCI2014 14-20 September 2014, Athens, Greece
Mobile Instruments Made Easy: Creating Musical Mobile Apps with LIBPD
and iOS, No Experience Necessary
Danny Holmes
Louisiana State University
Center for Computation and Technology
[email protected]
ABSTRACT
The quirks of programming native iOS applications can be
daunting, especially to someone not already familiar with
other text based programming languages. Fortunately, recent developments in Apple's Xcode IDE, along with the
open-source Pure Data wrapper, LIBPD, enable the process of creating an iOS native, standalone, musical mobile
app to be quite accessible. Basic implementation of LIBPD
for iOS can be reduced to a series of 10 simple and accessible steps requiring no actual knowledge of objective-c or
the LIBPD library itself, and requires no previous coding
experience, text-based or otherwise. In addition, the dragand-drop feature of Xcode's Storyboards allows the design
and programming of a native user interface to also be reduced to simple and accessible step-by-step instructions.
This is not just limited to buttons and sliders, but also includes the drag-and-drop creation of typical touch screen
gestures. Presently, this process will be outlined and explained, and its current and potential uses described.
1. INTRODUCTION
The development tools and modern languages available today have made mobile programming more accessible than
ever before [1]. While at least some experience and knowledge are still necessary to achieve all but the most rudimentary goals, it is entirely possible to engage those with
limited or even no prior experience or knowledge and enable them to create their own musically capable mobile applications with little time investment. Initiatives such as
the EMDM Academy (an Experimental Music and Digital Media Outreach) and the iOS Musical App-a-thon at
Louisiana State University are designing and implementing curriculum, as well as identifying and exploring potential benefits to music education.
One technique being explored is the rapid-prototyping of
standalone musical mobile applications by high school and
college students. The effective length of our classes and
workshops can be measured in hours (as opposed to days,
weeks, or months), and many of the students who have
been introduced to this process had no prior programming
Copyright: 2014 Danny Holmes et al. This is an open-access article distributed
under the terms of the u np s, which
permits unrestricted use, distribution, and reproduction in any medium, provided
the original author and source are credited.
experience. Thus far, the workshops have featured either
web-based applications or native iOS applications.
During an iOS Musical App-a-thon, students are introduced to mobile development using Apple's Xcode IDE
and Pure Data, and they design and create a new application all within a single 8-10 hour period. In order to eliminate the need for prior knowledge and reduce setup time,
it was necessary to stream-line the process for creating a
LIBPD enabled working environment for prototyping musical mobile apps with Xcode.
2. LIBPD IN 10 STEPS
The following step-by-step process outlines a basic method
for setting up LIBPD in an Xcode project. The code provided can simply be copied directly into the appropriate
portion of your own project, and only a few specific changes
to the code will be required.'
This process assumes you have already created a free
Apple developer account, have installed Xcode, and have
downloaded the LIBPD project from Github.
http:
http:
http:
'bit.ly/devregister
'bit.ly/dl_xcode
'bit.ly/libpdgithub
When the process is finished, the project will be set up
for testing your app using Xcode's built-in iOS simulator.
In order to put the app on a physical device, it will be necessary to join an existing development team or upgrade to
a paid developer account. Once your account is included
in an appropriate development profile, and your device is
provisioned, only one extra step is required to set up your
project for testing on an actual device.
2.1 Create an Xcode Project
Creating an Xcode project is fairly self-explanatory, but
a few options must be considered. First, open Xcode and
choose to "Create a New Xcode Project." Then select "Single View Application" (ensuring iOS is selected in the leftside menu) and fill out the project information. 2 Cur1 These instructions were derived from various resources (including
personal experience), but they began with the great information in Peter
Brinkman's Making Musical Apps r2].
2 Xcode 6 is due for public release in the third quarter of 2014.
With the new version, it may be necessary to also choose the language
(objective-c) and to deselect the option to use Core Data (unless it is essential to the app!).
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