I have a Flex application where some interactions cause many objects to require visual updates all at once. These updates translate into state changes for many MXML based components which have state based transitions. The transitions look great when just a handful of the components animate at the same time... but when all of them animate at once... the Flash Player just can't keep up.
Any ideas on how to create something of an animation pipeline so that everything can have a chance to keep up? Or maybe some other solution?
Did you try working with suspendBackgroundProcessing property of Effect or disableLayout property of Animate class descendants? You can define them on MXML animation definition nodes.
Personally, I try to stay away from the Adobe effects library as they're slow and not all that good. If you want animation 'groupings', consecutive animations, or even animation timelines, I would suggest you use TweenMax.
Related
How can i achieve this kind of animation effect (see link below) and where do I need to start learning, is this part of css or html5 or plugins, etc..
I have a startup knowledge in css and html5, but I have no idea how to achieve the effect.
http://www.terredevenements.com/en/
*the effect i'm referring to is the movement of the foreground images while the mouse hovers and still maintaining its background to be static
This effect is called "parallax scrolling"
The basic idea is to layer images on top of each other and move them simultaneously but at different speeds, foreground moving faster than background.
Capturing and utilizing mouse events can be done with javascript/jQuery, and the animation can also be done with those languages or in combination with CSS3 animations.
There are quite a few jQuery plugins out there that can help you quickly achieve this effect.
See parallax.js
Or for more plugins: http://bashooka.com/coding/best-jquery-parallax-plugins/
is there a way to detect that a fragment has started transition (in or out). What I am trying to acheve:
I have a fragment whcih has a SurfaceView with complex graphics in it. When I click on a button I want this fragment to slide away from the screen. But we all know, that SurfaceView can't be animated. So I want to replace it with a drawing cache bitmap before I start the transition.
There fore I need to know when the fragment starts transition. This is especially important for open transitions, because I call replace with image routine manually before out transition, but I need to know when the open transition was complete. Is there a better way than a timer (which seems awful to me).
Thanks.
P. S. compatibility lib
Off the top of my head I'd say attach an animation listener to the animations you are using (see Animation Listeners in the Android docs) ..depending on your situation this might mean you need to create and attach the animations in code, or you may be able to retrieve the animation and attach the listener when you create the component (activity/fragment). It depends on how your current implementation works, but the basic idea is to attach a listener to the animation that is about to run. The animation listener will tell you when the animation actually starts and actually finishes..
I am building an iOS Safari touch-based app and find CSS transitions and transforms work great.
But I have two things I can't seem to achieve using just JavaScript and CSS.
Usually I want the element to translate with a duration of 0.2s. But in code I occasionally want to instantly translate (initial positioning). If I update the duration to 0 or remove the transition style entirely, it doesn't seem to have an effect (acts as if the 0.2s is immutable)
When zooming I want to update the transform-origin property. This also does not seem to work, and seems stuck at my original stylesheet-set value. Specifically I am trying to do this on the gesturestart and gestureend events
Hopefully there is an approach to making this work. Maybe setTimeout async processing?
Update:
I have a js fiddle example to better illustrate my problem in #1, and it turns out that setTimeout fixes it, but it's a strange solution that I'd be interested in improving:
http://jsfiddle.net/w9E7t/
It seems like I'm unable to do these steps synchronously:
set appropriate classes for an instant transition
apply transition style
reset classes to their default (with transition) state
You can accomplish this by using two CSS classes, one which sets the timing-duration to 0s and the other which sets it to 200ms and then applying the classes programmatically in JS. Take a look at this JSFiddle for an example.
One of Web development's best practices is to separate your document's parts into structure/content (HTML), presentation (CSS), and interaction/behavior (JS). In the example above, the presentation of the content (a timed translation) stays defined in CSS while JS is used only to respond to an interaction (a MouseClick event).
You should be able to change an element's transform-origin using the WebkitTransformOrigin style property in JS. Here is an example JSFiddle. I tested this on my iPhone4 and it correctly logged the new transform-origins in the console. Again, this can also be achieved by using JS only to listen for the gesture events and updating the element's class, while keeping the style rules of the class defined in your presentation logic (CSS).
Note well: In my examples, I am updating the element's .className. Since it is possible that your elements already have many classes, you may need to implement addClass/removeClass functions to properly set the correct classes, several examples of which can found on the Web.
Update:
Sorry for the delay... There are two ways you can approach this problem and the first you have already discovered.
Another way to handle switching back the class name is to use the webkitTransitionEnd property. This fires whenever a transition on the element finishes. It would look like this:
document.getElementById('puck').addEventListener('webkitTransitionEnd', function() {
puck
.removeClass('without_transition')
.addClass('with_transition')
}, false);
Unfortunately, when the transition-duration property is set to 0, this event is not fired :( I'm not sure if that is by design or a bug, but that's just how it's currently implemented (though I'm guessing it's by design since at this point the browser is not really doing a transition but rather just applying the transformation). The workaround in this approach is to set the transition-duration to 1ms (which will essentially look instant).
While the setTimeout approach looks hackish, many mobile framework groups use it throughout their code since the function will fire after the transition that occurs from switching classes (similar to transitionEnd). Take a look at Sencha Touch and you will find it numerous times.
I've forked your JSfiddle to show my example here.
I've been told several times or I've read in various places (can't remember where exactly right now) not to use Tween classes from the Flex SDK but to use instead other animation libraries like Tweener, TweenMax, GTween, ...
What's wrong with using Flex tweens? Is it a performance issue?
If I want to do states transitions, should I make custom transitions with third-party libs?
For reference, here are some helpful things:
Actionscript Tween Performance Comparison - Browser crashes when you use default Flex 3 Tween classes.
Mr. Doob's List of Actionscript Tween Libraries.
If your goal is just to do state transitions in skins, then it is easiest to use the Flex Effect classes. Flex 4 is about to be released and it has completely rewritten its Effect library, much faster than Flex 2/3. I ran a quick test with tweening 100 mx.controls.Button instances 500ms each, one after the next, using TweenMax and Flex Effects, and TweenMax was about twice as fast (meaning I could see 15 objects moving at once instead of 7 or 8). So if you can, I would do all animations with TweenMax. Definitely the most versatile/popular/modular/optimized. But for skins, and because Flex Effects are ready to use in skins in MXML, use them.
Also check out Tink's Efflex Flex Effect Library for some nice Container/Viewstack effects (some in 3D).
Depending on what blogs you've been reading they might have an emphises on flash/actionscript. In which case it might recommend something like tweenlight or similar.
If you are using flex and its libraries then there is no reason not to use the flex effects (which are based on flex's version of Tween). Note that the flex Tween is different than the flash Tween. But you don't really have to worry about that, if you wish to move something, just use the Move effect, if you wish to fade something then just use the Fade effect.
Some people may recommend another tween package because it makes the overall SWF size smaller, but it depends on how you are building the end SWF. Are you deploying the SWF with the flex framework as an RSL (recommended although Google can't search your SWF yet if you do this, check this link) then it would be best to use the Flex effects. If you're not using the framework as an RSL then it would be a case of test you app to see what version came out as the bigger SWF file.
I've never had any issues with performance using the flex effects.
Some of the 3rd party tweening packages do effects that are not part of the flex library, but other than that I can't think of any good reason not to use the flex effects/tweens.
Is there a preferred way to handle animation when using Flex -- For instance, if I want to render a ball and bounce it around the screen?
If you're building a Flex application, you should use Flex's native Effect classes. They're probably already compiled into your app, since the core components use them, and you won't increase your SWF size with duplicate functionality like you would if you used another library. For simple animations, either mx.effects.AnimateProperty or mx.effects.Tween should work well.
If you're working on a regular ActionScript project (without the Flex framework), then I concur with the answer given by Marc Hughes. However, if that's the case, then please don't say you're using Flex because that implies that you're using the Flex framework and it can be very confusing. If you mean Flex Builder, then please use the full name to avoid potential misunderstandings.
You can't always use Flex's effect class with plain sprites. Certain effects expect your target object (the object to be tweened) to implement IUIComponent interface, while others don't. So you can either use mx.effects.Tween, or if you must use the one of the effects classses, you will need to coerce your sprite into a UIComponent.
Another option is to use one of the tween packages suggested above or roll your own with goasap!
goasap
I prefer to use a tweening library for things like this. Check these out:
Tweener
TweenLite / TweenMax
KitchenSync
I've had good luck actually using the first two, and have read great things about the last one.
You can use mx.effects.AnimateProperty even though your target is not a UIComponent.
If the tween you want to acheive is a simple one (Move, Resize, Fade etc) this saves you writing the boiler plate code that mx.effects.Tween requires.