animator 动画
动画的作用是让UI有动感, 看上去时尚。
Android中动画分两种方式:
一种方式是补间动画Tween Animation,就是说你定义一个开始和结束,中间的部分由程序运算得到。
另一种叫逐帧动画Frame Animation,就是说一帧一帧的连起来播放就变成了动画。
动画可以实现的效果:
1. 移动(Translation)
2. 透明度(alpha)
3. 旋转(rotate)
4. 缩放 (scale)
现在分别用例子来讲解:以下的实现都是用代码实现的(ObjectAnimator)
1. 移动(Translation)
主要代码
AnimatorSet set = new AnimatorSet() ; ObjectAnimator anim = ObjectAnimator .ofFloat(phone, "translationX", -500f, 0f); anim.setDuration(2000); ObjectAnimator anim3 = ObjectAnimator .ofFloat(phone, "translationX", 0f, -500f); anim3.setDuration(2000); ObjectAnimator anim2 = ObjectAnimator .ofFloat(phone, "translationY", 0f, -500f); anim2.setDuration(2000); ObjectAnimator anim4 = ObjectAnimator .ofFloat(phone, "translationY", -500f, 0f); anim4.setDuration(2000); AnimatorSet set3 = new AnimatorSet(); set3.play(anim4).before(anim3) ; AnimatorSet set2 = new AnimatorSet(); set2.play(anim2).before(set3) ; set.play(anim).before(set2); set.start();
讲解:anim 是从-500f 位置移动到当前位置(X轴);
anim3是从当前位置移动到-500f的位置(X轴);
anim2是从当前位置移动-500f的位置(Y轴);
anim 4是从-500f 位置移动到当前位置(Y轴);
AnimatorSet set3 = new AnimatorSet(); set3.play(anim4).before(anim3) ; AnimatorSet set2 = new AnimatorSet(); set2.play(anim2).before(set3) ; set.play(anim).before(set2); set.start();这样做的目的是为了,让目标view移动一个来回,从哪里出发, 最后回到出发的位置。
2. 透明度(alpha)
主要代码
AnimatorSet set = new AnimatorSet() ; ObjectAnimator anim = ObjectAnimator.ofFloat(phone, "alpha", 1f, 0f); anim.setDuration(2000); ObjectAnimator anim2 = ObjectAnimator.ofFloat(phone, "alpha", 0f, 1f); anim2.setDuration(2000); set.play(anim).before(anim2) ; set.start();
讲解: anim 从可见到不可见;
anim 从不可见到可见;
3. 旋转(rotate)
主要代码
AnimatorSet set = new AnimatorSet() ; ObjectAnimator anim = ObjectAnimator .ofFloat(phone, "rotationX", 0f, 180f); anim.setDuration(2000); ObjectAnimator anim2 = ObjectAnimator .ofFloat(phone, "rotationX", 180f, 0f); anim2.setDuration(2000); ObjectAnimator anim3 = ObjectAnimator .ofFloat(phone, "rotationY", 0f, 180f); anim3.setDuration(2000); ObjectAnimator anim4 = ObjectAnimator .ofFloat(phone, "rotationY", 180f, 0f); anim4.setDuration(2000); set.play(anim).before(anim2); set.play(anim3).before(anim4) ; set.start();
讲解:anim 从0度转180度(X轴)
anim2从180度转0度(X轴)
anim3从0度转180度(Y轴)
anim4从180度转0度(Y轴)
set.play(anim).before(anim2); set.play(anim3).before(anim4) ;这样写X和Y会同时旋转
4. 缩放 (scale)
主要代码
AnimatorSet set = new AnimatorSet() ; ObjectAnimator anim = ObjectAnimator .ofFloat(phone, "scaleX", 1f); anim.setDuration(1000); ObjectAnimator anim2 = ObjectAnimator .ofFloat(phone, "scaleX", 0.5f); anim2.setDuration(1000); ObjectAnimator anim3 = ObjectAnimator .ofFloat(phone, "scaleY", 1f); anim3.setDuration(1000); ObjectAnimator anim4 = ObjectAnimator .ofFloat(phone, "scaleY", 0.5f); anim4.setDuration(1000); ObjectAnimator anim5 = ObjectAnimator .ofFloat(phone, "scaleX", 0.5f); anim5.setDuration(1000); ObjectAnimator anim6 = ObjectAnimator .ofFloat(phone, "scaleX", 1f); anim6.setDuration(1000); ObjectAnimator anim7 = ObjectAnimator .ofFloat(phone, "scaleY",0.5f); anim7.setDuration(1000); ObjectAnimator anim8 = ObjectAnimator .ofFloat(phone, "scaleY", 1f); anim8.setDuration(1000); AnimatorSet set3 = new AnimatorSet() ; set3.play(anim5).before(anim6); AnimatorSet set2 = new AnimatorSet() ; set2.play(anim2).before(set3) ; AnimatorSet set4 = new AnimatorSet() ; set4.play(anim7).before(anim8) ; AnimatorSet set5 = new AnimatorSet() ; set5.play(anim4).before(set4); set.play(anim).before(set2); set.play(anim3).before(set5) ; set.start();
讲解:anim 从原来大小开始(X轴)
anim2 缩放到原来的1/2(X轴)
anim3从原来大小开始(Y轴)
anim4 缩放到原来的1/2(Y轴)
anim5从原来的1/2开始放大(X轴)
anim6放大到原来的大小(X轴)
anim7从原来的1/2开始放大(Y轴)
anim8放大到原来的大小(Y轴)