https://homeostasis.scs.carleton.ca/wiki/index.php?action=history&feed=atom&title=Mobile_Apps_2023W_Lecture_9 2026-04-08T03:15:38Z Revision history for this page on the wiki MediaWiki 1.42.1 https://homeostasis.scs.carleton.ca/wiki/index.php?title=Mobile_Apps_2023W_Lecture_9&diff=24350&oldid=prev 2023-02-08T21:02:09Z

<p>Created page with &quot;==Notes== &lt;pre&gt; Lecture 9 --------- Key challenge this semester is design as much as implementation So...I&#039;m going to design and build an app, and walk you all through it What websites have I been visiting? - I visit all kinds of places - I don&#039;t make bookmarks - yes there is history, but it isn&#039;t easy to view - would love the browser to eventually help direct my browsing towards things I, at a high level, want to visit rather than what is most easily in &quot;reach...&quot;</p> <p><b>New page</b></p><div>==Notes==<br /> <br /> &lt;pre&gt;<br /> Lecture 9<br /> ---------<br /> <br /> Key challenge this semester is design as much as implementation<br /> So...I&#039;m going to design and build an app, and walk you all through it<br /> <br /> What websites have I been visiting?<br /> - I visit all kinds of places<br /> - I don&#039;t make bookmarks<br /> - yes there is history, but it isn&#039;t easy to view<br /> - would love the browser to eventually help direct my browsing towards<br /> things I, at a high level, want to visit rather than what is most easily in &quot;reach&quot;<br /> <br /> (Basically, how do I do more &quot;healthy&quot; browsing rather than &quot;junk food&quot; browsing)<br /> <br /> Imagine a browser as a helpful assistant rather than a dumb app<br /> <br /> And doing it as a mobile app would be cool because, hey, that&#039;s where I browse the most.<br /> <br /> So what I want to do is do the simplest version of this app I can<br /> - not quite an MVP<br /> - gets access to all the info I want, can process it<br /> - the processing is an open-ended project, so will just do it in a minimal fashion<br /> <br /> Why is this good for class? It touches most everything<br /> - need to design a good UI<br /> - background processing<br /> - web technologies (embedded browser, maybe generating pages)<br /> - maybe access web services to store &amp; retrieve info of various kinds<br /> - search engines?<br /> - get general context<br /> - location (for showing relevant past browsing)<br /> - networking<br /> <br /> <br /> How do you start with this?<br /> - well, we already have<br /> - first you need to understand the tech<br /> - then you need to try building it<br /> - when you are building and you realize you don&#039;t know the tech,<br /> go and figure it out<br /> <br /> We&#039;ve done basic UI, embedded web browser, basic REST API<br /> <br /> The core of this, however, is the web history<br /> Remember, always start with your core data structures<br /> <br /> <br /> We want the data to be persistent, queryable, and structured. We&#039;re using a database!<br /> <br /> SQLite is the obvious choice for a database integrated into a mobile app<br /> <br /> So what&#039;s our initial goal<br /> - web browser<br /> - which shows the current URL<br /> - with the URL and other aspects of the page stored in a database on the device<br /> <br /> So initially we&#039;ll just need the following fields in our database:<br /> - date/time, host, URL, page title<br /> - entry for every visit<br /> - not compact, will have lots of redundancy<br /> - but easy to build for now<br /> <br /> Make sure you store &amp; represent all the data that could be relevant in their raw form<br /> - can later optimize and extract important characteristics<br /> <br /> Try for minimalism where you can<br /> - lowers complexity<br /> - try to maximize othonogonality of components, allow for component reuse<br /> <br /> So before we do the web browser with a history, to minimize complexity what do we next need to build?<br /> - simple app that stores info in a local database<br /> - then, we build a web browser with a history in an array<br /> - then we build a web with history in the local database<br /> <br /> First, how do we do databases like SQLite in android?<br /> - we could use built-in support for SQLite<br /> <br /> - we could use Rooms:*<br /> https://developer.android.com/training/data-storage/room<br /> <br /> - or we could use raw SQLite<br /> https://developer.android.com/training/data-storage/sqlite<br /> <br /> Rooms looks much nicer!<br /> <br /> <br /> Next, how do we get browser history? I see three approaches<br /> - have users browse in new app*<br /> - extract history from an existing browser on device<br /> - extract history from a cloud service<br /> <br /> How can we know what URL we have visited?<br /> - we&#039;ll just remember the webviews we&#039;ve visited<br /> <br /> Stop here, on Friday we&#039;ll look at some code using the Rooms API to access a SQL database<br /> - note I&#039;ll be in NYC, but shouldn&#039;t have too many technical issues hopefully<br /> <br /> On Friday we&#039;ll start however with you all telling everyone about your progress<br /> - would be great for you all to demo little bits of functionality that you have running<br /> <br /> Now I&#039;ll do tutorial checkoffs, answer questions<br /> <br /> I&#039;m going to make T3 be with databases, T4 will be a simple web browser<br /> &lt;/pre&gt;</div>

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