Mobile Computing
COMP5216
Week 02 Semester 2, 2020
Dr. Kanchana Thilakarathna School of Computer Science
The University of Sydney
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Outline
– App development workflow
– How to come up with app ideas through problems ? – Group Project
– Android Programming Basics
– Android app development process – Where are the resources ?
– Programming basics
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App development workflow
Six Steps
1. Define Goals
2. Analyse Requirements
3. Design UI: sketch, wireframe or storyboard
4. Design project structure
5. Implement codes
6. Test, debug, and release
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1. Design Goals
– GoalsvsIdeas – Value
Value Propositions
– Tomeettheneedsofcustomers/users
– Whatvaluedowedelivertocustomers?
– Whichoneofcustomers’problemswearehelpingtosolve?
– WhatbundlesofproductsandservicesareweofferingtoeachCustomer Segment ?
– Whichcustomerneedsarewesatisfying?
– Inbusinesscontext
– Offeringsfromtheproduct
– Whatdistinguishesitselffromitscompetitors
• Quantitative – price and efficiency
• Qualitative – overall customer experience and outcome
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2. Requirement Analyses
– Howtodeliverthevalues – Tasks
– Userscenarios
– Howtheappwillfunction – Keyinteractionsintheapp – Secondaryfunctions
• Features in the first version that are “nice to have” – Understandthefield
– Findoutwhetherthereareotherappsouttheredoingthesamething
– Obtaininsightsoftheproblem
– Finddesigninspirationforyourapp
– Findinformationonthetechnicalrequirementforyourapp – Findouthowyoucanmarketandmonetizeyourapp
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Business Model Canvas
– Proposed by business theorist Alexander Osterwalder
– A strategic management and lean startup template for
developing new or documenting existing business models.
– It is a visual chart with elements describing a firm’s or product’s value proposition, infrastructure, customers, and finances.
– https://www.alexandercowan.com/business-model-canvas-templates/
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The Business Model Canvas
Day
Month Year
Key Partners
Key Activities
Value Propositions
Customer Segments
Cost Structure
Revenue Streams
www.businessmodelgeneration.com
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Key Resources
Channels
Designed for:
Designed by:
Customer Relationships
On: Iteration:
No.
The Lean Principle
– Entrepreneurs are everywhere – There’s never been a better time to
innovate
– Think big. Start small. Scale Fast
– Entrepreneurship is management – Validating learning
– Innovation accounting
– Build-Measure-Learn
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Build – Measure – Learn
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Minimum Viable Product
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3. UI (User Interface)
– Platform specific UI styles
– iOS – https://developer.apple.com/design/human-interface-guidelines/ – Android – https://developer.android.com/design/
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3. UI (User Interface)
– Sketching wireframes – Tools (not free)
– Balsamiq – https://balsamiq.com/
– Moqups- https://moqups.com/
– HotGloo – https://www.hotgloo.com/
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3. UI (User Interface)
– Tools (free)
– MS PowerPoint
– Apple Keynote
– Apple – https://developer.apple.com/design/resources/
– Android – https://material.io/design/introduction/#principles
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3. UI (User Interface)
– Learn from good designs
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3. UI (User Interface)
– Test your UI on the device
– POP – https://marvelapp.com/pop/ – Balsamiq – https://balsamiq.com/
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4. Design Project Structure
– Frontend
– UI implementation
• MVC framework (Model-View-Controller)
• MVP (Model-View-Presenter) and MVVM (Model-View-View-Model) • Avoid holistic placement of UI elements
– Backend
– Use cloud service as much as possible
– Always think about the impact of your design on other stakeholders of the eco-systems
– Users
– Networks – …,
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5. Implementing the Code
– Mobileappdevelopmentisincreasinglygettingeasier! – OSAPIs
– Web/CloudservicesAPIs – ThirdpartySDKs
– Thirdpartylibraries
– Developasateam
– 1-Front-end,1-Back-end,1-UI/UX,1-Manager – Agilesoftwaredevelopment
– Scrum-https://www.atlassian.com/agile/scrum
– Takeadvantagefromcollaborativetools – Bitbucket-https://www.bitbucket.org
– Github-https://github.com
– Slack-https://slack.com
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6. Testing and Debugging
– Not only functions
– But also the feedback from users, such as how they use the app
– Verifying value propositions – Taking note of their actions
– Adapting your UI/UX to them – App Analytics SDKs
– Beta version release
– Lets you to distribute the app to known users
– Customer development
– Users other than your friends and family members: getting out of the
building The University of Sydney
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How to find app ideas?
Ideas
– Existing ideas
– Even if you find someone else working on the same thing, you’re
probably not too late.
– Worrying that you’re late is one of the signs of a good idea
– Extension to existing ideas – Analogy between two domains
• Airbnb vs Bike sharing
• Facebook vs Linkedin – Add an extra feature
– Opposite thinking
• Hospital vs Home health-care
– Innovative ideas The University of Sydney
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Ideas
– The way to get good ideas is not to try to think of your assignment
– The most common mistake startups make is to solve problems no one has
– It yields bad ideas that sound plausible enough to fool you into working
on them
– “made-up” or “sitcom” startup ideas
– Two types of successful apps
– Entering a market with existing competitors, but armed with some secret
weapon that will get them all the users. • Example?
– Entering a market that looks small, but which will turn out to be big. • Example?
– Look for problems, preferably problems you have yourself
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Own problems
– The general problems you have – Online social network
– Something to get real-time bus timetable – Garage sale
– Discussion forum
– Something needed in your previous job –…
– Something at least some users who really need, not just may be one day, but want it urgently.
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Where are the problems ?
– Alert to opportunities
– Dropbox: forgetting USB sticks
– Live in the future, then build what’s missing. – Be open-minded
– Turn off the filters that usually prevent you from seeing them
• Why is your inbox overflowing? Why do you get so much email? What problems are people trying to solve by sending you email? Are there better ways to solve them? Why do you keep emails around after you’ve read them? Is an inbox the optimal tool for that?
– Live in the future, then build what seems interesting. The University of Sydney
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Inter-disciplinary Problems
– Learning about some other field, you’ll probably see problems that software could solve.
– (a) the inhabitants of that domain are not as likely as software people to have already solved their problems with software, and
– (b) since you come into the new domain totally ignorant, you don’t even know what the status quo is to take it for granted.
– Taking a class on, say, genetics; or better still, go work for a biotech company.
– One way to ensure you do a good job solving other people’s problems is to make them your own.
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Problems
– Serve a small initial group
– High demandsàhigh competition
– E.g. Apple, Google, Facebook, Microsoft, etc.
– Make the users who care about your product happy – First iPhone does not have copy/paste function
– Germ problems
– Hard to tell, even experienced investors – Airbnb
• Let hosts rent out space on their floors during conventions. They didn’t foresee the expansion of this idea; it forced itself upon them gradually
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Any ideas ?
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Critical Factors of Startup Success
1. Idea
2. Leader
3. Team
4. Capital
5. Plan
6. Execution
7. Timing
8. Crisis response
9. Marketing
10. Growth
– https://www.entrepreneur.com/article/252813
– These are experiences, rather than rules.
It’s not just the classes that make a university such a good place to crank oneself into the future. You’re also surrounded by other people trying to do the same thing. If you work together with them on projects, you’ll end up producing not just organic ideas, but organic ideas with organic founding teams—and that, empirically, is the best combination.
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Group Project
COMP5216 S2, 2020
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Group Project
– Refer to the Project Guidelines document on Canvas
– Two Phases – Proposal and Final
– Minimum feature set:
– Graphical user interface (GUI) to effectively interact with the user.
– At least one form of data communication using either Cellular, WiFi, Bluetooth, etc.
– At least one technique to save network bandwidth usage, computation resource usage or device battery usage.
– At least one method to secure the communication or data storage. – Come and test/discuss your idea with me !
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App development workflow
Six Steps
1. Define Goals
2. Analyse Requirements
3. Design UI: sketch, wireframe or storyboard
4. Design project structure
5. Implement codes
6. Test, debug, and release
Proposal Phase
Final Phase
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Group Project submission
– Refer to the Project Guidelines document on Canvas
– Proposal Phase: Report (hard & electronic)
– Final Phase:
– Report (hard & electronic)
– Presentation slides
– Video
– Source Code
– Presentation and Demo
Deliverables Due Time
Proposal Electronic submission 5:00pm, 28/09/2019 (Monday, Week 06)
Final Electronic submission 5:00pm, 06/11/2019 (Friday, Week 10)
Presentation & Demo 5:00pm, 09/11/2019 (Monday, Week 11)
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Group enrolment
– Maximum Group size is FIVE
– Enroll to groups via Canvas.
– Pick a group number attached to the tutorial of most number of group members.
– Tutorial swap procedure.
– First, try to swap it yourself.
– If the system does not allow you do so, record your details here.
– https://unisyd- my.sharepoint.com/:x:/g/personal/chamara_kattadige_sydney_edu_au /Eb4wS1Y01s9Es_pokqWGCrwB0UgFR6NEWJQgvTgDpn8aPA?rtime= 6jwiy1lN2Eg
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Android Programming Basics – 1
COMP5216 S2, 2020
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What is Android?
Major components of Android Stack
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– Applications: Users interact with the device via the apps. Can be either first party or third party.
– Android Framework: Provides basic functions such as communication between apps, managing voice calls or managing app life cycles.
– Native Libraries: C/C++ libraries that contain instructions to the device on handling different
types of data. E.g. Webkit, SSL, SQLite, and OpenGL.
– Android Runtime: Dalvik Virtual Machine and Core Libraries.
– Hardware Abstraction Layer (HAL): Converts the Java API calls to system calls that is understood by the Linux kernel.
– Linux Kernel: Additional modifications done by Google to make it suitable for smartphones (E.g. power management). Handles all conventional operating system functions such as process Page 34 management and memory management.
It is easy to develop apps…
– IDE – Android Studio – Languages
– Java/Kotlin to develop apps
– XML to describe data resources
– SDKs hide the complexity from developers – E.g.:
• Java API Framework • Google Play Services
– You don’t need to know the details of how the APIs work. The University of Sydney
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Android app development process
1. Create the project in Android Studio and choose an appropriate template.
2. Define a layout for each screen that has UI elements. You can place UI elements on the screen using the layout editor, or you can write code directly in the Extensible Markup Language (XML).
3. Write code using the Java programming language. Create source code for all of the app’s components.
4. Build and run the app on real and virtual devices. Use the default build configuration or create custom builds for different versions of your app.©
5. Test and debug the app’s logic and UI.
6. Publish the app by assembling the final APK (package file) and distributing it through channels such as Google Play.
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Resources to help you learn – Android developer training courses
– Codelabs with suggested homework assignments: Codelabs for Android Developer Fundamentals
codelabs
– The Android Developer YouTube channel is a great source of tutorials and tips.
– Android vocabulary
– Inspire looking at Android Developer Stories
– Community Support:
– The Android team posts news and tips in the official Android blog.
– Android developers blog.
– Stack Overflow. If you run into a problem, chances are high that someone has already posted an answer.
– Type [android] in the search box. The [] brackets indicate that you want to search for posts that have been tagged as being about Android.
– Concept reference chapters: Android Developer Fundamentals — Concepts
– Source code in GitHub for starter apps and solution code for apps that you create in the
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Resources to help you learn
– Android developer fundamentals course – Unit 1.4: Resources to help you learn
– This page contains a great collection of links to many resources organized into categories;
– Android Developer documentation – Android studio documentation
– Design
– Develop
– Distribute
– Blogs
– Other resources
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Building blocks of Android
App components
– Activities – Services
– Broadcast Receivers – Content Providers
Activating components
– Intent
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Activity
– OneofthebasicbuildingblockofAndroid
– MostcommoncomponentofAndroiddevelopment
– Representsasinglescreenwithauserinterface
– Asingleappcanhavemultipleactivities.
E.g. A game app might have different activities for login screen, scores page, and the game play screens
– AssociatedwithaXMLfilethatdefinesthearrangementofGUI components.
– https://developer.android.com/guide/components/activities/intro- activities
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Activity Example
Activity Operation is written in Java
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Activity Layout and other resources
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activity_main.xml
Various Layouts
– Layout defines the visual structure of the GUI.
– View hierarchy
Objects – Layouts
• Linear Layout
• Relative Layout
• Web view
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Objects – Widgets • Buttons
• Text view
Layouts
– Can declare Layouts
– Writing the XML
– Using Android Studio’s “Layout Editor”
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Activity Lifecycle
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Activity Lifecycle
– You can override lifecycle methods to develop your customized activity.
– E.g. What to do after starting the appàOverride onCreate() method – From tutorial 1;
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Few ideas on object oriented programming
– The elements we discussed such as Activities, Buttons, TextViews are all classes. What does it mean?
– Classes and Instances – Attributes and Methods
– Class is a blueprint of something. For example, a Smartphone class will define that each smartphone must have attributes such as length, width, thickness, brand, OS, owner etc. and methods such as switch on, switch off, sleep.
– Kanchana’s phone is a specific instance of the smartphone class, length=8cm, width=5cm, brand=“Nexus”, owner=“Kanchana” …. and so on.
– Thilakarathna’s phone is a specific instance of the smartphone class, length=6cm, width=4cm, brand=“iPhone”, owner=“Thilakarathna” …. and so on.
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Few ideas on object oriented programming
– In the previous example, we creates instances of Activity class such as MainActivity.
– When we set the Text, Width, and Height of these elements we were assigning values the attributes.
– We used the onCreate() method of the Activity class to include our GUI logic.
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Declaring components – AndroidManifest.xml
– Describes essential information about your app to Android OS – Examples:
– App package name
– Minimum API level required by the app
– User permissions
– Declare third party API libraries
– Declare app’s components, e.g. Activity
– Declare component capabilities through Intents and Intent filters
https://developer.android.com/guide/topics/manifest/manifest-intro
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Intents
– Intent is a messaging object to request an action from another app component.
– Primary use-cases:
– To start an activity
– To start a service
– To deliver a broadcast
– Intent types:
– Explicit Intents: Communicate within the same application. Need to
specify the exact name of the component , e.g. class name.
– Implicit Intents: Communicate between applications. Requested by declaring the general action to perform, e.g. location.
– https://developer.android.com/guide/components/intents-filters The University of Sydney
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Building bocks of an Intent
1. Component name
– Name of the component to start
• Must specify the name for Explicit Intent, e.g. class name of the new
Activity.
• Empty for Implicit Intent
2. Action
– String that specifies the desired operation, e.g. view or pick
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• • • •
ACTION_DIAL – Dial a number
ACTION_EDIT – Display data to edit
ACTION_SYNC – Synchronise device data with a server ACTION_MAIN – Start as initial activity of the app.
Building bocks of an Intent
3. Data
– –
– –
Data and type of data (MIME type) associated with the Intent
Type of data should be related to the action
• E.g. If the action is ACTION_DIAL, data should be the phone number.
Formatted as URI object (Uniform Resource Identifier)
• Uri.prase(“http://www.google.com”)
Note: To set both URI and MIME type, use setDataAndType()
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Building bocks of an Intent
4. Category
– String containing additional information about the component
• CATEGORY_BROWSABLE – To start a web browser to display data
– Specify the category with addCategory() 5. Extras
– Key-value pairs that carry additional information to complete the action
– Add extra info with putExtra()
6. Flags
– Metadata for the intent
• E.g. How to launch the activity, how to treat it after launching, etc.
– Can set flags using setFalgs()
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Example 1
– Start another activity using an Intent – Example: Tutorial 2
– What type of an Intent is used ?
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Example 2
– Communicate between apps.
– By declaring the general action to perform. In this case,
– Action:ACTION_VIEW
– Data: Formatted as Uniform Resource Identifier (URI object) to send Intent Data
– What type of intent is this?
– What can go wrong with the code above code block?
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Intent Filters
– Declare which Intents that your app can receive with intent- filter element in your AndroidManifest.xml
– The manifest file describes essential information about your app to the Android build tools, the Android operating system, and Google Play.
– This is how Android pass Implicit Intents to relevant apps
– Define
– E.g. Declaration to receive ACTION_SEND intent with text data
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Intent Filters
– Who had a look at the AndroidManifest.xml files of Tutorial 1? – Were there any Intent filter?
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Intent Filters
– ACTION_MAIN indicates this activity is the main entry point when the user launch the app and does not expect any intent data.
– CATEGORY_LAUNCHER indicates that activity’s icon should be placed in the system’s app launcher.
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What’s Next ?
– InWeek3;
– CapabilitiesofMobileDevices,e.g.sensors,location,etc. – Androidbuildingblocks
• Services
• Broadcast Receiver • Content Provider
– Project
– GuidelineisonCanvas
– Startforminggroupsandthinkingaboutideas
– Tutorial2
– Tutorswillhelpyoutosign-in/registerforprojectgroups – Registerthegroupwiththetutorialclassofmostmembers
– Pleaseuse“COMP5216”onthesubjectwhenyouemailme. The University of Sydney
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