Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 1 Informatics 121 Software Design I Lecture 3 Duplication of course material for any commercial purpose without the explicit written permission of the professor is prohibited.

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 2 Discussion There will be discussion next Monday and Wednesday Please join your designated discussion

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 3 Today Defining design Feasibility and desirability Four types of design Design cycle

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 4 Our definition To decide upon a plan for a novel change in the world that, when realized, satisfies stakeholders

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 5 Design designerplan makerchange in the world audienceexperiences other stakeholders

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 6 Software design software designersource code compiler * runnable program usersexperiences other stakeholders [ * or, at times, the person who installs and configures the software instead of the compiler]

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 7 Feasibility and desirability designerplan maker audienceexperiences other stakeholders feasibility change in the world

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 8 Feasibility and desirability designerplan makerchange in the world audience other stakeholders desirability experiences feasibility

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 9 Four types of design desirability feasibility what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 10 Four types of design satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 11 Four types of software design satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? application design interaction design architecture design implementation design

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 12 Design an instant message system satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? application design interaction design architecture design implementation design

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 13 Design a word processor satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? application design interaction design architecture design implementation design

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 14 Design problem and solution design problemdesign solution

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 15 Design project design problemdesign solution design project

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 16 Design cycle analyzeevaluate synthesize

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 17 Design cycle analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 18 Goals A goal represents an explicit acknowledgment of a desired result that the eventual design solution must achieve Goals may be suggested by any of the stakeholders – client – other stakeholders – audience – designer Goals change over time, and may or may not be (partially) addressed by the current state of the design solution

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 19 Example goals The luxury airplane must be 10% more fuel-efficient than its predecessor The library must be able to hold 250,000 books The award must be representative of the professional society that is commissioning it

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 20 Constraints A constraint represents an explicit acknowledgment of a condition that restricts the design project Constraints may be suggested by any of the stakeholders – client – other stakeholders – audience – designer Constraints change over time, and may or may not be (partially) met by the current state of the design project

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 21 Example constraints The luxury airplane must weigh less than 50,000 pounds The library must not violate federal disability laws The award must cost less than $1000 to produce

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 22 Assumptions An assumption represents a fact that is taken for granted, may or may not be true, and influences the design project Assumptions may be made by any of the stakeholders – client – other stakeholders – audience – designer Assumptions change over time, and may or may not be (partially) fulfilled by the current state of the design project

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 23 Example assumptions The average person weighs 85 kilograms The library needs to serve the community with an area stocked with personal computers The professional society’s logo is red and white, which therefore must be its preferred colors for the award

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 24 Decisions A decision represents a specific choice of how to further the design solution, typically after some amount of consideration Decisions are the sole responsibility of the designer, though they can be (heavily) influenced by other stakeholders Decisions change over time, and new decisions may or may not (partially) align with the current state of the design project

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 25 Example decisions The fuselage and wings of the luxury airplane shall be made out of carbon composites The library shall have bookshelves that are not movable The award shall be made out of colored glass

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 26 Idea An idea represents a thought or opinion, ranging from highly unformed to fully formed, that potentially shapes the design solution Ideas typically are the sole responsibility of the designer, though they may be inspired by many different sources Ideas change over time, and new ideas may or may not (partially) align with the current state of the design project

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 27 Example ideas What if the luxury airplane had a shower on board? Perhaps the library membership cards should have RFID tags, so a visitor can simply grab the books they want, walk by an automated scanner, and have their books be on loan I am thinking that the award should be a variant of last year’s award

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 28 Design an instant message system analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 29 Design a word processor analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 30 Design the software to fly a drone analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 31 Design studio 1 Your client is massbroadcast.com, a new company that seeks to enable organizations to reach out to a broad audience with a pre-determined message – via phone, text, instant message, Hangouts, Skype, and other media. The company plans to make money from clients who seek to advertise their products. Being altruistic, however, the company also wants to offer support for emergency alerts. The company has sought you out, because you are an excellent designer. All of the software design is in your hands.

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 32 Design studio 1 Identify the audience and other stakeholders Identify possible goals, constraints, and assumptions Bring two printed copies to discussion, Monday or Wednesday – one for the TAs – one for your group Your group will be announced at the start of your discussion