AndroidAnimationBuilder

This tiny 'library' is supposed to help you build complex animations and behavior easily by offering a promise-like API.

Here's a simple example animation in four steps:

new AndroidAnimationBuilder(animatedView)
                .rotateBy(20)
                .then().rotateBy(-40)
                .then().reset()
                .execute();

makes:

... and here is a complex example (this is the one from the demo app) to show off what can be achieved while still keeping it readable:

new AndroidAnimationBuilder(v).setDefaultStepDuration(1000)
        // first step: quick preparations.
        .alpha(0).ms(10).run(view -> startButton.setEnabled(false))

        // dramatic entrance: Appear spinning
        .then().alpha(1).rotateBy(-90)

        // some more spinning fun. All those steps will take 1 second each.
        .then().rotateBy(180)
        .then().rotateBy(-285 -360)
        .then().rotateBy(15)

        // some moving fun
        .then().translateX(-1000).ms(600)

        // phew. Let's have a break
        .pause(500)

        // hop out of the screen before moving:
        // 'run(..)' is executed before the animation of the step is started
        .then().run(view -> view.setTranslationX(1500)).translateX(-1500)
        .then().translateX(0).ms(100)

        .then().translateY(-100).scaleX(2f).ms(500)
        .then().run(view -> view.setBackgroundColor(randomColor()))

        .then().rotateBy(90).scaleX(1).scaleY(3)

        // finish the show!
        // reset: Undo everything that is not defined in the step to what it was
        // before the animation was started.
        .then().reset().scaleX(0).scaleY(0).ms(2000)

        // everything back to the start
        .then().reset().ms(1).runAfter(view -> startButton.setEnabled(true))
        .execute();

FAQ

I don't need it, I can do that with xml!

If the xml is enough for your needs, you should definitely use the xml. The AnimationBuilder is supposed to help in complex cases, where a sequence of animation steps is required, probably with hooks in between.

Huh? Isn't that what ViewPropertyAnimators are for?

Absolutely! The AnimationBuilder internally even uses ViewPropertyAnimators. But with the Builder, stringing them together into a sequence and adding hooks somewhere along the way should be much easier.

License

MIT license

Copyright (c) 2017 Matthias Schicker

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Gradle?

Sorry, not yet. For now, just copy&paste AndroidAnimationBuilder.java to your project and you're good. Will probably add gradle support if someone requests it. Working on it :)