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Posts tagged: workaround

SSRS and HTML rendering of ordered list

By , 11/14/2016 2:02 PM

Microsoft’s SQL Server Reporting Services supports rendering of HTML tags, but for some reason that support stuck in 1990s – only very limited set is supported. And even using that set is problematic.

Case in point – ordered list. While officially supported – the way it is rendered is the stuff nightmares are made off. Jumble of original tags generously intermixed with DIVs and SPANs – it’s a wonder it renders at all.

And sometimes it doesn’t. If you try to view a report in Internet Explorer (especially from older, but still actively used versions of SSRS like 2008) numbering get screwed.
Continue reading 'SSRS and HTML rendering of ordered list'»

Simulating Pebble GPath in Rocky.js

By , 08/17/2016 3:56 PM

RockyJS is a black magic voodoo from Pebble Dev team. It allows you to run your JavaScript code on the actual smartwatch (unlike PebbleJS that runs on the phone). When RockyJS debuted it ran as a simulation in a browser, but since then it matured and now runs in Pebble emulators and on actual hardware.

RockyJS changed drastically since that web release. It resembles C code less and takes more standardized JavaScript approach. During that transition some features were lost. One of them is Pebble GPath concept – a graphical object that consist of set of coordinates that you can freely move and rotate. In particular missing commands gpath_move_to, gpath_rotate_to and gpath_draw_outline that move, rotate and draw the GPath. When I was porting my first Pebble watchface to Rocky I used those extensively. You can read about that implementation complete with the source code here. But now the commands are gone and I needed a substitution. Continue reading 'Simulating Pebble GPath in Rocky.js'»

Full control of your Limitless LED/Milight bulbs from Amazon Echo

By , 05/12/2016 11:34 AM

Limitless LED Limitless LED offers full color RGBW light bulbs that you can control over Wi-Fi/4G from your computer, phone or smartwatch. They’re an inexpensive alternative to Philips Hue and they look really cool.
But I, being lazy ass that I am, was wondering if you can control the lights from Amazon Echo by voice commands alone. Out of the box Echo and Limitless LED don’t recognize each other. Amazon can see and control Hue, but not Limitless LED. Fortunately geniuses of BWS Systems came up with a really cool piece of software – home automation bridge “HA-Bridge”. It’s free and written in Java so it can run pretty much in any environment under any OS. What it does – it emulates Philips Hue API so other devices on your network – like Echo – can see and interact with it. Continue reading 'Full control of your Limitless LED/Milight bulbs from Amazon Echo'»

Flicker-Free IFRAME refresh

By , 05/05/2016 3:05 PM

One of our projects consists of single parent page and “widgets” that display secondary (classic ASPX webform) pages. A recent feature request was to auto-refresh widget information at given intervals. On the surface it was pretty straghtforward:

<iframe id="xIfrWidget0"></iframe>
var ifr = document.getElementById('xIfrWidget');

setInterval(function () {
   ifr.src = 'widget.aspx';
}, 2000)

The problem with this approach – there’s an ugly flicker of white between page refresh and the goal was to keep displaying current IFRAME content up until refreshed content is ready. Yes, there’re various AJAX-ified methods (including ASP.NET UpdatePanel) – but they add unnecessary overhead and may cause other issues.

The solution was suggested by this Stack Overflow post. The idea is to have secondary, hidden IFRAME into which perform actual load. Once load complete – switch IFRAMES – currently visible with old content becomes hidden, and hidden one with new content becomes visible. It goes something like this: Continue reading 'Flicker-Free IFRAME refresh'»

Pebbles, rectangles and stack overflow

By , 04/20/2016 2:17 PM

UntitledWhile working on my Pebble watchface “Future Time” I have encountered persistent annoying problem – watchface would run for a while and then crash – and not only crash, but actually restart the watch. What made this even more frustrating – after 3 restarts in a row Pebble would revert to recovery mode and complete firmware reinstall was required (did I accidentally write a Pebble virus?).
When I dug into device logs I found out that every restart was given reason: “Dangerous Stack Overflow”. Which is kinda strange – I don’t have any recursions nor deeply nested function calls nor large local variables. I tried lots of things – including extreme ones like declaring all local function variables as global or static – nothing helped.
Finally Christian form Pebble developers forum shed a light. He pointed out that I use a lot of GRect constructs which is basic rectangle building block for pretty much anything from defining layers to graphics functions. I used GRect inline directly inside function calls, which I thought wasn’t a big deal, after all “everybody does that” – including Pebble in its examples. Well, as Christian pointed out those GRects are kind of local variables, and either memory is not reclaimed fast enough when they go out of scope or they spring memory leak.
Keeping this in mind I created a global GRect variable and when needed to use a GRect in local function, first I’d assign it’s value to the variable and then use variable in the function.
So something like this:

static void layer_update(Layer *layer, GContext *ctx) {
   //...
   graphics_draw_rect(ctx, GRect(10, 10, 30, 30));
   //...
   graphics_draw_bitmap_in_rect(ctx, bitmap, GRect(20, 20, 40, 40));
}

Becomes thus:

GRect temp_rect;

static void layer_update(Layer *layer, GContext *ctx) {
   //...
   temp_rect = GRect(10, 10, 30, 30);
   graphics_draw_rect(ctx, temp_rect);
   //...
   temp_rect = GRect(20, 20, 40, 40);
   graphics_draw_bitmap_in_rect(ctx, bitmap, temp_rect);
}

That’s it. This simple change cured the plague, no more crashes, restarts or recovery – just smooth sailing.

Unblock my heart, i mean, iPhone for Pebble geocoding

By , 03/29/2016 11:15 AM

Cobblestyle I’ve recently updated code for Cobblestyle Pebble Watchface to take advantage of very cool geocoding service called Nominatim by Open Street Maps.

Nominatim is used in two places: Direct lookup is used in watchface’s config page to lookup coordinates of a place by its name for custom location setting; reverse lookup is used to lookup location name by its coordinates to display name on actual watchface.

It was working fine – on Pebble watches connected to Android phones. It was failing miserably on iOS, so iPhone Pebble users were getting neither location nor weather updates. And it was pretty puzzling for a while until I obtained logs from running watchface thanks to invaluable help from Robin.

Turned out iPhone Pebble app was plain simple blocked by Nominatim service, every attempt to retreive location resulted in message being sent back “You have violated acceptable policy”. Which was kinda surprising since I just started using the service. When I contacted Nominatim support, they told me that apparently some Pebble app running from iPhone abused the service pretty badly, running hundreds of requests per second. And since the only way they can detect requesting app is by it’s User Agent string – all apps spotting iPhone Pebble UA were blocked.

Support suggested to set UA string specific to the app so it could be easily identifiable. Standard approach to set headers on xmlHttpRequest object is .setRequestHeader(..). Unfortunately by many browsers and clients it is considered unsafe to spoof UA via request headers. Fortunately iOS allows that, so all I have to do is catch and ignore erros in other clients. Basically this line of code solved the issue:

try {xhr.setRequestHeader("User-Agent", "Cobblestyle Pebble Watchface");} catch(e){}

Thanks to this as of version 2.19 Cobblestyle watchface correctly displays weather and location information. Yay.

Restore natural picture look on Samsung smart TV

By , 02/02/2016 10:04 PM

I really like my new smart TV from Samsung it has tons of bells and whistles. But one thing I noticed – no matter what I watch – series or movies, streaming or broadcast – picture has a “teleplay” feeling – like the action is happening on stage in the theater. If you recall what later Twilight Zone episodes look like you’d know what I am talking about. Maybe it’s supposed to look like this, but I like “film” feeling more. So I found a setting that restores natural picture look:

CYMERA_20160202_215011
Go to your TV menu, then select Picture -> Picture Options -> Auto Motion Plus and turn it off.

Fixing problem with Yahoo geolocation service

By , 01/25/2016 5:04 PM

Recently two Pebble watchfaces I’ve developed based on Paul Joel designes: Clean&Smart and Cobblestyle began to experience weather update issues – as in “weather was not updated at all”. Looking into the issue I found a weird thing: If you set your location manually – weather worked. But automatic weather based on phone location did not.

The way automatic location works is pretty straighforward. First this function is called to determine location:

function getLocation() {
  navigator.geolocation.getCurrentPosition(
    locationSuccess,
    locationError,
    {timeout: 15000, maximumAge: 60000}
  );
}

It uses phone location services (GPS, if its available, otherwise network-based location). In case of success it calls locationSuccess function. And in my tests it always called it, so location was determined successfully. Continue reading 'Fixing problem with Yahoo geolocation service'»

Solved: Issue with Pebble framebuffer after notification is dismissed

By , 01/08/2016 1:15 PM

Effect Layer Issue I’ve encountered a weird issue while working with EffectLayer Library (a visual effect library for Pebble smartwatch). In this particular watchface called Clean & Smart I used “invert” effect which inverts colors of the watchface should the user choose that option in settings. It was working fine when option changed when watchface was loaded/unload and behaved weirdly only in one particular scenario: when you would receive a notification (email, text etc.) and then dismiss it. Upon coming back from notification to watchface invert effect would only partially cover the watchface (as seen on the screenshot).
I don’t know exactly what was happening, but had a theory. Continue reading 'Solved: Issue with Pebble framebuffer after notification is dismissed'»

Solution: Live Writer Error “Invalid Response Document” while connecting to WordPress

By , 03/23/2015 1:02 PM

If you’re trying to connect to your WordPress blog from Windows Live Writer desktop client, you may get this dreaded error message:

Invalid Server Response – The response to the blogger.getUsersBlogs method received from the blog server was invalid:┬áInvalid response document returned from XmlRpc Server

Invalid Response

This means that instead of expected XML response your blog sent back plain html or text message which is most likely some kind of error message. To see actual message you can either trace request response in an HTTP sniffer like Fiddler or simple enter endpoint url for your blog remote access (e.g. http://your.site.com/wordpress/xmlrpc.php) into your browser address bar.
Continue reading 'Solution: Live Writer Error “Invalid Response Document” while connecting to WordPress'»

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