Humor4u

This time, we wrap up the series on cartoon animation techniques with a demo that shows a few of the techniques in the context of a larger application. Because it's nice to know how to write the code, but you might also be wondering why you might want to. For some real-world context, you could also check out games such as Candy Crush Saga (a horribly addictive game I've gotten sucked into that's less like casual gaming and more like casual crack). It uses a veritable plethora of cartoon animation techniques to keep the player engaged with the game and disengaged from their life. This and other cartoon animation techniques were discussed in the talk A Moving Experience at Google I/O 2013 Code: http://developer.android.com/shareables/devbytes/ToonGame.zip YouTube: https://www.youtube.com/watch?v=8sG3bAPOhyw&list=PLWz5rJ2EKKc_XOgcRukSoKKjewFJZrKV0

Horrible things can result from calling requestLayout() during a layout pass. DON'T DO THIS . The demo that I wrote to show why this is bad seems very contrived, but I have since run across application code that did nearly the exact same thing, explicitly calling requestLayout() during onLayout(). Ugh. Typically, the cases where this problem occurs are a tad more subtle than that. YouTube: https://www.youtube.com/watch?v=HbAeTGoKG6k Code: http://developer.android.com/shareables/devbytes/RequestDuringLayout.zip

I'm starting to prepare presentations for the ~8 hours of talks that Romain and I are giving at Devoxx in a couple of weeks. "Preparing" generally entails mostly worrying, followed by a mad rush of writing slides and code at night, on the long flight, after beers, between talks, and sometimes during the talks. It's a busy time of year. I realized that the organizers of Devoxx had recently released all of the recorded talks from last year into the wild (read: they're free on parleys.com ), so it seemed worth linking to them in case anyone wanted to see what we had to say last time around. I'll give a plug for the conference and the Parleys site here. If there were an ad banner, it'd go here. Not because I'm paid (I would make a poor ad salesman, apparently), but because I think that both the conference and the parleys site rock. The organizers do a great job of putting it all together, and the recordings and presentation of the talks on parleys.com...

One of the app developers here on Android asked me about the best way to animate adding and removing items from a UI. Specifically, he wanted to fade items in and out as they became visible/invisible. So I wrote up a sample activity that used ViewPropertyAnimator , showing how to set the visibility at the right time (making it visible before fading it in, listening for the onAnimationEnd() to set it invisible after fading it out). Pretty straightforward, but if you haven't played around a lot with the new animation classes yet (WHY HAVEN'T YOU?!?!), it's probably not obvious: To make it invisible: invisibleButton.animate().alpha(0f).setListener(new AnimatorListenerAdapter() { public void onAnimationEnd(Animator animation) { invisibleButton.setVisibility(View.INVISIBLE); invisibleButton.setAlpha(1f); invisibleButton.animate().setListener(null); } })...

Romain and I gave several talks at the excellent Devoxx conference in balmy Antwerp last November. The video of one of these talks, Android UI Development: Tips, Tricks and Techniques , has just been published for free on the Parleys.com site. All of the conference talks have been available for months to subscribers (79 Euros), but for those who haven't gotten around to registering quite yet, the talks are published incrementally for free throughout the year, and our UI Tips talk is now available. This talk covers a mix of topics, from "Garbage Zero" (techniques to avoid producing garbage when it matters) to an exploration of various tools and performance techniques that we use to produce better Android code. Check out the video here: Android UI Development: Tips, Tricks and Techniques .

Here are slides for two of the approximately 871 talks that Romain Guy and I gave at Devoxx last month (and again at the SF Android User Group meeting a couple of days ago). Videos of all of the Devoxx sessions are already posted on the excellent Parleys site for a small subscription fee, and should be made freely available sometime in the next few months. You probably want to check out those videos for the complete details. But in case you were at the talks, are sick of listening to us speak, or simply want to peruse the slideware, here you go... Android Graphics and Animation Android UI Development: Tips, Tricks and Techniques