Posts Tagged Android
Flash Builder Profiler – Fixing Memory Leak on ExternalInterface
Posted by Mark Doherty in Android, Devices, Flash Lite, Flash Player, Mobile Content on June 17, 2010
One of the most common problems with Flash applications are memory leaks, programming flaws that cause Flash Player to loose access to memory that it could recycle otherwise. In the mobile space it’s crucial to understand memory management to get the most out of the Flash Player, and ultimately to ensure a smooth ride for your consumers.
Flash Player memory management
Flash Player makes use of automatic memory management, to help you to create applications with ease and with less code. In fact the Flash Player uses a pretty simple mechanism that determines how many times you have referenced a particular object. Once an object has nothing referencing it then it can be garbage collected – predictably it’s called “reference counting”.
The following is a great example of reference counting in action, notice that I have created a Geolocation object (geo) and added updateHandler as a listener function for update events. This counts as a reference against updateHandler:
var geo:Geolocation = new Geolocation();
geo.addEventListener(GeolocationEvent.UPDATE, updateHandler);
function updateHandler(event:GeolocationEvent):void
{
geo=null;
trace(event.longitude);
}
The updateHandler function marks the geo object null, tagging it for deletion by the garbage collector which is great. The problem is that the geo object still has a reference to updateHandler, and therefore the geo object cannot be deleted until we remove the listener and free the reference up.
function updateHandler(event:GeolocationEvent):void
{
geo.removeEventListener(GeolocationEvent.UPDATE, updateHandler);
geo=null;
trace(event.longitude);
}
Memory leaks are easy to create in Flash, and even harder to debug later. It’s therefore essential to build your applications with memory in mind and use all tools at your disposal to keep checking for leaks, slow performance, and run away code.
Flash Builder Profiler
Flash Builder 4 ships with a new feature called the Profiler and in the video below I’ll show you how to use it to solve a memory leak. Now don’t be fooled, this memory leak took a few hours to solve in reality – these aren’t easy problems to solve.
In fact I found two memory leaks, the first is the ExternalInterface.addCallback holding onto a function reference. The other is more complex, and I have marked it “Flash Player Bug” as I believe this is a problem with the runtime itself.
EVA on Android – App in a Week
Posted by Mark Doherty in Android, Creative Suite 5, Devices, Flash Player, Mobile Content on June 10, 2010
I have just completed my App in a Week session on targeting Mobile and Devices, as promised, here are the source files for EVA on Android. So that you don’t get lost in the huge swathe of code let’s run through some of the features to get you started.
If you missed todays session you can catch it here and view the running application here.
Setup:
Target Multiple Screens:
The goal of this application was to target Android devices running AIR, or indeed the Flash Player running in mobile browsers. So it was important to include some pointers on how to dynamically layout the application.
I chose to implement two pretty simple examples of how to do this using the widgetComponent and the footerMenu. In the Application class I listen to the “Event.RESIZE” event through the doLayout function. As you stretch the SWF (use the standalone player) you can see the widgetComponent always displays in the middle, the footerMenu will always be at the bottom.
Of course the menu, widgets and background should all change dynamically. This won’t require a huge set of changes and as you can see it’s quite simple to control the layout. In a later build I will investigate a more dynamic approach to laying out the UI.
PHP+MySQL Backend
To demonstrate the data-centric features of Flash Builder, Mihai and Piotr created a database with PHP services that describe common Evangelist activities as well as data about us. In the mobile demo I have coded as few of these database interactions in the UsersService class:
- “UsersService.getByUsername” – Is used to login and returns an object with user details including their name, photo url etc
- “UsersService.setLocation” – Is used to store the lastest location after login, this is then synchronized with other Evangelists.
I have created a User object to represent the user of the service, this class also manages the loading of the user image using ContentLoader. The primary function of ContentLoader is to abstract the loading of SWF/image files, handling the various possible error cases.
User Location
An interesting new feature of Adobe AIR on Android is the ability to use the GPS hardware to get an accurate location fix. Although EVA was designed to run inside, or outside of the browser and as such I have built a few fallbacks.
When the application is running in the browser (Capabilities.playerType==”PlugIn”) I have used an HTML5 feature to get the location. This is achieved by using the ExternalInterface class, a bridge that Flash uses to communicate with Javascript.
In addition to these two approaches I have also deployed the MaxMind GeoIP service on my blog. This is a huge database of IP addresses that can be used to determine an approximate location, usually your nearest city. This is used when the application is running in standalone mode for debugging purposes, or as a failure fallback.
Using each of these methods I can reverse geocode the latitude and longitude to discover the users current location. The UI displays the current city and country. The open geonames database is an incredible free webservices that cover all manner of data, I couldn’t have wished for more.
Local Weather
One of the more interesting features of the application is the local weather service. There are only two services that can produce weather data for a give latitude and longitude, and those are Geonames and Google Weather.
I chose Google because it comes with the added bonus of providing a weather icon to display. Unfortunately this icon isn’t up to the quality of Serge’s design and so I ultimately swap it out, but at least I can easily change the URL.
The most fun part was easily finding a piece of code that calculates the Sunset (SunriseSunset.as). I was able to find and port a piece of JavaScript code that does the trick, although annoyingly I cannot find the author to thank them. Using this I can swap in the night icons for weather, nice 
Flash Settings:
- The stage is running in low quality mode – perfect for use with device fonts
- Layers have been minimized and flattened as much as possible
- The Frame rate of the application is 15FPS – as low as possible
Asset Optimizations:
- The EVA background is an 8KB PNG-8 128
- All other images are mobile optimized PNG-8 128 Dithered and under 4KB
- Bitmap caching is not used, the application is relatively static
- Special care has been taken to ensure that all assets are snapped to pixels (not 23.43 etc)
- No assets are loaded off stage and nothing is invisible, ever – if they are unused, then they are unloaded
- All assets use “Sprite” as their base class, as set in the properties panel in Flash Professional
Text Optimizations:
- TLF is not used anywhere due to performance and size issues
- Only device fonts are used, they perform and render much better
Flex:
- Flex is not used due to the overhead of the framework on devices.
In later blog posts I will discuss the Widgets in more depth, including the Social and Radar widgets. It’s also worth noting that Tom did a great job to deliver his P2P widget ready for integration, amazingly within 12kb!
DOWNLOAD
Flash Player 10.1 Beta launch at Google IO
Posted by Mark Doherty in Android, Flash Player, Industry News, Mobile Content, Mobile World Congress on May 20, 2010
Surprise! Today at Google I/O Vic Gundotra, Google VP Engineering announced Flash Player 10.1 and Adobe AIR 2.5 running on FroYo. The launch today represents a milestone that we’ve been working towards for some time, and all of us at Adobe are hugely excited to see Flash Player 10.1 finally get into the hands of consumers.
The beta is now waiting on the Android Market for Nexus One and other Android 2.2 users to test out. General availability is expected in June 2010.
While today’s announcement is all about Android, our target mobile operating systems for Flash Player also include Windows Phone 7, webOS, Symbian, and BlackBerry. Adobe provides a porting kit and Linux-based reference implementation to Open Screen Project partners to allow them to port Flash Player 10.1 to other platforms. These ports are subject to Adobe certification and must pass our standards for compatibility, performance and usability in order for devices to be marketed as “Includes Adobe Flash Player.”
Flash Player 10.1 on Android
In all, Flash Player 10.1 has been built from the ground up, and not just for mobile phones but for the desktops, tablets, netbooks and even televisions, consoles and set-top boxes. We have been working extremely hard on the runtime of course, but on top of that many of you have been working with us to optimize your web content for Flash Player 10.1.
Here is a landing page that features a number of websites that highlight the variety of Flash Player user experiences available on a mobile device. These sites and most popular websites that use Flash can now be accessed on smartphones supporting Flash Player 10.1.
Since we demonstrated the Flash Player on Android at the Mobile World Congress there have been a number of decisions made, changes implemented and tweaks applied to Flash Player 10.1. These changes focused on usability, integration, performance and power management – so let’s look at some of these in more detail.
Installation and updates
I have documented the process over here in another post. Suffice to say, the process is simple and demonstrates our commitment with the Open Screen Project to ensuring the evolution of Flash Player on mobile and devices.
Multi-touch
Due to time constraints with shipping FroYo it hasn’t been possible to make all of the Android browser changes required to enable multi-touch in Flash Player. Web enablement has always been the top priority and so this (extremely complex) integration will happen later. AIR 2.5 on Android is multi-touch enabled and so it’s still possible to use your fingers, thumbs and toes as necessary on Android.
Accelerometer
One of the cool new feature of Flash Player 10.1 is the accelerometer API, making Flash Player the first browser technology to support access to this hardware. In Device Central CS5 we have added some emulation support for the API, you can read more here.
Focused Mode (single tap)
The Android and other browsers support multi-touch for viewing web pages, so that you can pan and zoom around non-optimized sites with ease. To ensure that touch events are received by Flash or the browser appropriately we have created focused mode. It works very simply using a priority system, so if you tap the Flash content that you want to interact with Flash receives the touch events, if Flash doesn’t pick up the event then it’s passed to the browser. Tapping on the HTML will revert this focus priority back to the browser.
Smartzoom (double tap)
When a user double taps a piece of Flash content it will zoom to fit the screen, while maintaining the correct aspect ratio. The content is still viewed in the context of the HTML, rather than launching into full screen mode. This ensures that content remains in embedded mode – which makes sense given that this is the predominant usage of Flash on the web.
FullScreen (AS-only)
Another change to our previous showing is that FullScreen mode is now controlled via actionscript, just as it is on the desktop. So if you want your video player or game to playback using the full screen, then you’ll need to use this code: stage.displayState=StageDisplayState.FULL_SCREEN;
Smart Rendering
We have already seen some of the benefits of this effort on the desktop version of Flash Player 10.1. Essentially it means that Flash content that’s not visible to the user will not be rendered and will receive limited CPU time. SWFs that are off-screen and/or consuming required resources can also be put to sleep and resumed on demand. You can control this behaviour by applying priority values to SWF files using the embed tag.
Video Hardware Decoding
One of the hardest features to get right has been video hardware decoding, and for the beta version this will not be enabled.
Sleep Mode
The player will be put to sleep along with the device to conserve power. So if you fall asleep watching youtube then you won’t wake up to talking cats at 4am – tried and tested. cats…
Out-of-Memory Management
For me, this is the kick-ass feature that should always have been arbitrating the use of the Flash Player. If your content is not optimized correctly, has serious memory leaks and manages to use too much CPU power then it’ll go in the “sin bin” These SWFs will render with a “click-to-play” button that the user can control as necessary.
Device Events
As with Flash Lite before it, Flash Player 10.1 has to be a good citizen on a mobile phone. So if you receive a call or change application then Flash Player will respond appropriately, which typically means shutting down or pausing depending on the platform.
Minimum Spec
As has been documented before, our minimum spec for Flash Player 10.1 is ARM11-Cortex A8/9 at 550mhz. For Cortex-A8 processors we require NEON, which enables improved multi-media playback for a lower mhz rating.
If you don’t know what any of that means then I wouldn’t be too concerned. These chipsets represent the bulk of what our OEM partners are shipping, or planning to ship moving forward – and this list will undoubtedly expand.
Demos
Use Flash Builder to develop Adobe AIR apps for Android
Use Flash Professional CS5 to develop Adobe AIR apps for Android
See Flash Player 10.1 running on Android
AIR 2.5 on Android
Also announced today is an expanded pre-release of AIR 2.5 for Android devices. Many of us on the Evangelism team have been playing with this for several weeks now, and it’s seriously cool.
Upcoming E-Seminar Series: App in a Week
Posted by Mark Doherty in Android, Conference, Creative Suite 5, Flash Lite, Flash Player, Industry News, Mobile Content on May 7, 2010
With CS5 now available the EMEA Evangelism team have been hard at work prepping for our upcoming tour and the Online Developer Week. The course of events will fall between June 7th – 10th covering everything from design in Photoshop CS5 to development, and even deployment of your applications using the Flash Platform suite of tools.
The tools covered will include Flash Builder, Flash Professional, Flash Catalyst, Flex 4 and the Flash Player 10.1 and AIR 2 runtimes. In my own session we’ll also be covering Device Central and some asset optimization guidelines for targeting mobile phones.
We’ll also look at P2P with Flash Player 10.1 as well as Livecycle, PHP and Java integration on the backend.
Schedule:
June 7th – 12:00 – 13:00 GMT Erase the Designer to Developer gap: Adding interactions to your design with Serge Jespers
June 7th – 15:00 – 16:00 GMT Connecting your design to PHP services with Mihai Corlan
June 8th – 12:00 – 13:00 GMT Connecting a web application to a J2EE backend using Flash Builder 4 with Michael Chaize
June 8th – 15:00 – 16:00 GMT Working with Flash CS5 components in your Flash Builder 4 project with Mike Jones
June 9th – 12:00 – 13:00 GMT Going multi-user with P2P in Flash Player 10.1 with Tom Krcha
June 9th – 15:00 – 16:00 GMT Developing multi-user applications with LiveCycle services with Tom Krcha
June 10th – 12:00 – 13:00 GMT Bringing web Applications to the desktop with AIR 2.0 with Piotr Walczyscyn
Jun 10th – 15:00 – 16:00 GMT Code once and run on multiple mobile devices with Mark Doherty
We’ve been busy for the past week building “EVA” to demonstrate all of the above. I think you’ll be really impressed with it and of course we’ll be providing the code after for you to use in your own applications.
SIGN UP HERE
Flash Player 10.1 on Motorola Droid and Motorola Backflip
Posted by Mark Doherty in Android, Flash Player on January 7, 2010
The latest in our series of Flash Player 10.1 video demos comes hot on the heels of Motorola’s announcement of the Backflip, Droid and it’s Milestone variant.
You will remember that at MAX 2009 we showed a disguised Android device, previously unannounced, running Flash Player 10.1. That was in fact the Droid, and with our continued partnership with Motorola and Google it’s great to see Flash Player 10.1 start to filter through the platform. From a developer perspective, this is a good indicator that we’re now able to bring Flash to devices by platform; in this case Android 2.x.
In his video demo, Adrian shows the New York Times website which is now able to detect these Android devices and provide a more complete web experience including video, images and animations which until now have only been suited to the desktop.
Most news and entertainment sites today are using Flash to playback their video content, engaging with their audiences using rich media throughout their sites.
The award winning BBC News site is also shown in this video, and interestingly shows some nice device detection from the BBC whereby highly optimized video is sent across the web as they detect lower bandwidths using the Flash Media Server.
As with our other videos, these are teasers to give you some idea of the wide scope of devices including WebOS, Android, Windows Mobile, Symbian and Linux that will be able to run Flash Player 10.1 later this year.
Enjoy..