stl - Dave's Blog


Multiple Windows in Win10 JavaScript UWP apps

2018 Mar 10, 1:47

Win10 Changes

In Win8.1 JavaScript UWP apps we supported multiple windows using MSApp DOM APIs. In Win10 we use and window and a new MSApp API getViewId and the previous MSApp APIs are gone:

Win10 Win8.1
Create new window MSApp.createNewView
New window object window MSAppView
viewId MSApp.getViewId(window) MSAppView.viewId

WinRT viewId

We use and window for creating new windows, but then to interact with WinRT APIs we add the MSApp.getViewId API. It takes a window object as a parameter and returns a viewId number that can be used with the various Windows.UI.ViewManagement.ApplicationViewSwitcher APIs.

Delaying Visibility

Views in WinRT normally start hidden and the end developer uses something like TryShowAsStandaloneAsync to display the view once it is fully prepared. In the web world, shows a window immediately and the end user can watch as content is loaded and rendered. To have your new windows act like views in WinRT and not display immediately we have added a option. For example
let newWindow ="", null, "msHideView=yes");

Primary Window Differences

The primary window that is initially opened by the OS acts differently than the secondary windows that it opens:

Primary Secondary Allowed Disallowed
window.close Close app Close window
Navigation restrictions ACUR only No restrictions

The restriction on secondary windows such that they cannot open secondary windows could change in the future depending on feedback.

Same Origin Communication Restrictions

Lastly, there is a very difficult technical issue preventing us from properly supporting synchronous, same-origin, cross-window, script calls. That is, when you open a window that's same origin, script in one window is allowed to directly call functions in the other window and some of these calls will fail. postMessage calls work just fine and is the recommended way to do things if that's possible for you. Otherwise we continue to work on improving this.


Tweet from David Risney

2016 Aug 23, 1:48
Loved @PFTompkins ep of @SamplerShow  including PFTs reaction to Ice-Ts reaction to fake Ice-T PFT conversation.

Tweet from David_Risney

2015 Oct 7, 2:17
On whistleblower Edward Scissorhands: "to cast him out… simply because he has scissors for hands… that's strange" …

Retweet of Ka_Sauer

2015 Jul 26, 10:32
*whistling inconspicuously" “@YenitaLibre: “@labaume_de: RT @inthemoodfortw:”// Usted y me.”

Retweet of chockenberry

2015 Mar 9, 11:56
More about the attack on the developer tools: …

Retweet of matthew_d_green

2015 Feb 18, 10:07
If you're a technology worker who has any access to sensitive keys or secrets, read all the way through this piece. …

From Inside Edward Snowden’s Life as a Robot: Wizner had...

2014 Jun 23, 7:04

From Inside Edward Snowden’s Life as a Robot:

Wizner had to jump on a phone call during a meeting with his whistleblower client. When he got off the phone, he found that Snowden had rolled the bot into civil liberties lawyer Jameel Jaffer’s office and was discussing the 702 provision of the Foreign Intelligence Surveillance Act. “It was kind of cool,” Wizner says.

It is neat but they’re marketing video is at times strangely terrifying. Put different music on when the Susan-bot comes up behind the unknowing Mark and this could be a horror movie trailer.

PermalinkCommentsedward-snowden beam robot telepresence

mostlysignssomeportents: More than 90% of Americans believe...

2014 Jun 7, 9:55


More than 90% of Americans believe that the US government is unduly influenced by money, and the Mayday.US super PAC is raising $5M to fund the election campaigns of politicians who’ll pledge to dismantle super PACs and enact other campaign finance reforms. They raised more than $1M in 30 days last month, and this month, the goal is $5M. It’s the brainchild of Lawrence Lessig, who’s going to run prototype the project by running five electoral campaigns in 2014, and use the lessons of those projects to win enough anti-corruption seats in 2016 to effect real change.

Again, I’m not able to contribute to Mayday.US, because I’m a Canadian and Briton. But I ask my American friends to put in $10, and promise that I’ll put CAD1000 into any comparable Canadian effort and/or £1000 into a comparable UK effort. We all win when countries embrace evidence-based policy guided by doing what’s best for its citizens, rather than lining the pockets of corrupting multinationals.


Please reblog!


location.hash and are bad and they should feel bad

2014 May 22, 9:25
The DOM location interface exposes the HTML document's URI parsed into its properties. However, it is ancient and has problems that bug me but otherwise rarely show up in the real world. Complaining about mostly theoretical issues is why blogging exists, so here goes:
  • The location object's search, hash, and protocol properties are all misnomers that lead to confusion about the correct terms:
    • The 'search' property returns the URI's query property. The query property isn't limited to containing search terms.
    • The 'hash' property returns the URI's fragment property. This one is just named after its delimiter. It should be called the fragment.
    • The 'protocol' property returns the URI's scheme property. A URI's scheme isn't necessarily a protocol. The http URI scheme of course uses the HTTP protocol, but the https URI scheme is the HTTP protocol over SSL/TLS - there is no HTTPS protocol. Similarly for something like mailto - there is no mailto wire protocol.
  • The 'hash' and 'search' location properties both return null in the case that their corresponding URI property doesn't exist or if its the empty string. A URI with no query property and a URI with an empty string query property that are otherwise the same, are not equal URIs and are allowed by HTTP to return different content. Similarly for the fragment. Unless the specific URI scheme defines otherwise, an empty query or hash isn't the same as no query or hash.
But like complaining about the number of minutes in an hour none of this can ever change without huge compat issues on the web. Accordingly I can only give my thanks to Anne van Kesteren and the awesome work on the URL standard moving towards a more sane (but still working practically within the constraints of compat) location object and URI parsing in the browser.

Words with Hints Windows 8 App Development Notes

2013 Jul 4, 1:00

My second completed app for the Windows Store was Words with Hints a companion to Words with Friends or other Scrabble like games that gives you *ahem* hints. You provide your tiles and optionally letters placed in a line on the board and Words with Hints gives you word options.

I wrote this the first time by building a regular expression to check against my dictionary of words which made for a slow app on the Surface. In subsequent release of the app I now spawn four web workers (one for each of the Surface's cores) each with its own fourth of my dictionary. Each fourth of the dictionary is a trie which makes it easy for me to discard whole chunks of possible combinations of Scrabble letters as I walk the tree of possibilities.

The dictionaries are large and takes a noticeable amount of time to load on the Surface. The best performing mechanism I found to load them is as JavaScript source files that simply define their portion of the dictionary on the global object and synchronously (only on the worker so not blocking the UI thread). Putting them into .js files means they take advantage of bytecode caching making them load faster. However because the data is mostly strings and not code there is a dramatic size increase when the app is installed. The total size of the four dictionary .js files is about 44Mb. The bytecode cache for the dictionary files is about double that 88Mb meaning the dictionary plus the bytecode cache is 132Mb.

To handle the bother of postMessage communication and web workers this was the first app in which I used my promise MessagePort project which I'll discuss more in the future.

This is the first app in which I used the Microsoft Ad SDK. It was difficult to find the install for the SDK and difficult to use their website, but once setup, the Ad SDK was easy to import into VS and easy to use in my app.

PermalinkCommentsdevelopment technical windows windows-store words-with-hints

“Jon Hamm And Adam Scott’s ‘greatest Event In Tv History’...

2012 Oct 12, 8:41

Jon Hamm And Adam Scott’s ‘greatest Event In Tv History’ Was A Tribute To A Forgotten ’80s Classic
If you know more about Simon and Simon than its intro and general premise, you’re better at TV than I am. If you’ve never heard of Simon and Simon, you’re the BEST at TV because, honestly, Simon & Simon — a CBS series about two mismatched brothers who ran a private detective service; it ran for eight seasons — wasn’t good.

Source: Uproxx

PermalinkCommentshumor jon-hamm adam-scott video

Reddit explains Obamacare

2012 Jul 1, 5:16

PPACA (aka Obamacare) broken down into its main subsections with brief explinations and citations linking into the actual PPACA document (why is it always PDF?).

Its interesting to see the very small number of parts folks are complaining about versus the rest which mostly strikes me as “how could this not already be the case?”

I’m no expert, and everything I posted here I attribute mostly to Wikipedia or the actual bill itself, with an occasional Google search to clarify stuff. I am absolutely not a difinitive source or expert. I was just trying to simplify things as best I can without dumbing them down. I’m glad that many of you found this helpful.”

PermalinkCommentshealth-care politics PPACA obama obamacare law legal

C++ Algorithms: next_permutation()

2012 May 4, 1:56

Breakdown of the STL’s implementation of next_permutation.  Ever wondered how that works?

PermalinkCommentstechnical stl c++ algorithm permutation math programming

Alternate IPv4 Forms - URI Host Syntax Notes

2012 Mar 14, 4:30

By the URI RFC there is only one way to represent a particular IPv4 address in the host of a URI. This is the standard dotted decimal notation of four bytes in decimal with no leading zeroes delimited by periods. And no leading zeros are allowed which means there's only one textual representation of a particular IPv4 address.

However as discussed in the URI RFC, there are other forms of IPv4 addresses that although not officially allowed are generally accepted. Many implementations used inet_aton to parse the address from the URI which accepts more than just dotted decimal. Instead of dotted decimal, each dot delimited part can be in decimal, octal (if preceded by a '0') or hex (if preceded by '0x' or '0X'). And that's each section individually - they don't have to match. And there need not be 4 parts: there can be between 1 and 4 (inclusive). In case of less than 4, the last part in the string represents all of the left over bytes, not just one.

For example the following are all equivalent:
Standard dotted decimal form
Fewer parts
All of the above

The bread and butter of URI related security issues is when one part of the system disagrees with another about the interpretation of the URI. So this non-standard, non-normal form syntax has been been a great source of security issues in the past. Its mostly well known now (CreateUri normalizes these non-normal forms to dotted decimal), but occasionally a good tool for bypassing naive URI blocking systems.

PermalinkCommentsurl inet_aton uri technical host programming ipv4

Why I Like Glitch

2012 Feb 17, 4:00

Sarah and I have been enjoying Glitch for a while now. Reviews are usually positive although occasionally biting (but mostly accurate).

I enjoy Glitch as a game of exploration: exploring the game's lands with hidden and secret rooms, and exploring the games skills and game mechanics. The issue with my enjoyment coming from exploration is that after I've explored all streets and learned all skills I've got nothing left to do. But I've found that even after that I can have fun writing client side JavaScript against Glitch's web APIs making tools (I work on the Glitch Helperator) for use in Glitch. And on a semi-regular basis they add new features reviving my interest in the game itself.

PermalinkCommentsvideo-game glitch glitch-helperator me project game

Replacing Delicious with Google Reader

2011 Nov 17, 11:00

I had previously replaced my use of Delicious with Google Reader. Delicious had a number of issues during their switch over from Yahoo to the new owners and I was eventually fed up enough to remove it from daily use. I used Delicious to do the following things:

  • Create a list of things to read later
  • Save things to read again in the future
  • Search through things I read and enjoyed (esp via tags)
  • Annotate and share things on my blog
I realized that since I did most of my web browsing in Google Reader now anyway I may as well make use of its features. I star things to note I want to read it later or save to read again later. I can annotate with notes in Google Reader and I can share items to my web site by way of the shared items feed. Additionally for when I'm not in Google Reader there's a bookmarklet to add an arbitrary web site as a shared item in Google Reader.

Of course I wrote this and switched over about 1 week before Google removed the sharing feature from Google Reader. I'm irritated but in practice it forced me to find a different option which has worked out mostly better. New blog post coming soon about that...

PermalinkCommentsblog delicious me technical google-reader google feed

Draft: The Salmon Protocol

2010 Jun 20, 1:18Protocol for doing distributed commenting and implemented by Google Buzz! "This document defines a lightweight, robust, and secure protocol for sending unsolicited notifications — especially comments and responses on syndicated feed content — to specified endpoints; along with rules to enable resulting content to itself be syndicated robustly and securely."PermalinkCommentscomment blog atom rss google buzz salmon reference specification protocol syndication technical

View PDFs on Android

2010 Jan 10, 4:07

Irritatingly, my G1 won't show me PDFs so I've made the Google Docs PDF viewer which will load PDFs on the web up in Google Docs. Google Docs has the useful ability to display PDFs in web browsers without any Adobe software and works (mostly) on Android.

This was very easy to put together as an Android activity. First its necessary to register the application as handling PDFs from the web. This is done via the intent-filter declaration in the manifest:

      action android:name="android.intent.action.VIEW"/
      data android:scheme="http" android:mimeType="application/pdf"/
      category android:name="android.intent.category.DEFAULT"/
      category android:name="android.intent.category.BROWSABLE"/
The action part says my activity will view PDFs, the data part says it accepts data with the PDF mime-type and with a URL that has an HTTP scheme. The browsable category is necessary to allow links from a browser to open this activity.

Second, the activity opens up the browser to Google Docs pointing to the PDF.

   Intent intent = new Intent();
    "" + 

This is very simple code to invoke a new intent browsing to a newly constructed URL for the PDF in Google Docs. That was easy.PermalinkCommentsgoogle docs technical g1 code activity programming android google pdf

YouTube - JavaScript: The Good Parts

2009 Oct 28, 11:02"This session will expose the goodness in JavaScript, an outstanding dynamic programming language. Within the language is an elegant subset that is vastly superior to the language as a whole, being more reliable, readable and maintainable." Zeke recommended listening to his talks.PermalinkCommentsgoogle video technical douglas-crockford javascript programming presentation jslint web browser

Conceptual Trends and Current Topics

2009 Oct 15, 6:33"Besides the canonical Bristlecone Pine, there are many other organism on earth that will outlive you. Photographer Rachel Sussman has been traveling around the world to find and photograph them."
PermalinkCommentsphoto time nature biology age
Older Entries Creative Commons License Some rights reserved.