public static void expand(final View v) {
v.measure(MeasureSpec.makeMeasureSpec(((View)v.getParent()).getWidth(), MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(1024, MeasureSpec.AT_MOST));
final int targtetHeight = v.getMeasuredHeight();
v.getLayoutParams().height = 0;
v.setVisibility(View.VISIBLE);
Animation a = new Animation()
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
v.getLayoutParams().height = interpolatedTime == 1
? LayoutParams.WRAP_CONTENT
: (int)(targtetHeight * interpolatedTime);
Log.i("CHEOK", "E v.getLayoutParams().height = " + v.getLayoutParams().height);
v.requestLayout();
下面的日志信息被打印出来。
10-09 12:29:58.808: I/CHEOK(7874): E v.getLayoutParams().height = 0
10-09 12:29:58.808: I/CHEOK(7874): E v.getLayoutParams().height = 0
10-09 12:29:58.918: I/CHEOK(7874): E v.getLayoutParams().height = 11
10-09 12:29:59.015: I/CHEOK(7874): E v.getLayoutParams().height = 35
10-09 12:29:59.117: I/CHEOK(7874): E v.getLayoutParams().height = 64
10-09 12:29:59.215: I/CHEOK(7874): E v.getLayoutParams().height = 85
10-09 12:29:59.316: I/CHEOK(7874): E v.getLayoutParams().height = -2
10-09 12:29:59.406: I/CHEOK(7874): E v.getLayoutParams().height = -2
新的高度每隔~100ms发生一次。因此,动画的FPS约为10fps。
我想看看什么是理想的动画帧率。我删除了v.requestLayout();
。我得到以下记录。
10-09 12:32:06.547: I/CHEOK(8926): E v.getLayoutParams().height = 0
10-09 12:32:06.562: I/CHEOK(8926): E v.getLayoutParams().height = 0
10-09 12:32:06.605: I/CHEOK(8926): E v.getLayoutParams().height = 4
10-09 12:32:06.625: I/CHEOK(8926): E v.getLayoutParams().height = 7
10-09 12:32:06.644: I/CHEOK(8926): E v.getLayoutParams().height = 10
10-09 12:32:06.664: I/CHEOK(8926): E v.getLayoutParams().height = 14
10-09 12:32:06.679: I/CHEOK(8926): E v.getLayoutParams().height = 18
10-09 12:32:06.699: I/CHEOK(8926): E v.getLayoutParams().height = 22
10-09 12:32:06.715: I/CHEOK(8926): E v.getLayoutParams().height = 27
10-09 12:32:06.734: I/CHEOK(8926): E v.getLayoutParams().height = 32
10-09 12:32:06.750: I/CHEOK(8926): E v.getLayoutParams().height = 37
10-09 12:32:06.769: I/CHEOK(8926): E v.getLayoutParams().height = 42
10-09 12:32:06.785: I/CHEOK(8926): E v.getLayoutParams().height = 47
10-09 12:32:06.804: I/CHEOK(8926): E v.getLayoutParams().height = 52
10-09 12:32:06.828: I/CHEOK(8926): E v.getLayoutParams().height = 59
10-09 12:32:06.840: I/CHEOK(8926): E v.getLayoutParams().height = 62
10-09 12:32:06.863: I/CHEOK(8926): E v.getLayoutParams().height = 67
10-09 12:32:06.879: I/CHEOK(8926): E v.getLayoutParams().height = 71
10-09 12:32:06.894: I/CHEOK(8926): E v.getLayoutParams().height = 75
10-09 12:32:06.910: I/CHEOK(8926): E v.getLayoutParams().height = 79
10-09 12:32:06.929: I/CHEOK(8926): E v.getLayoutParams().height = 82
10-09 12:32:06.945: I/CHEOK(8926): E v.getLayoutParams().height = 85
10-09 12:32:06.965: I/CHEOK(8926): E v.getLayoutParams().height = 88
10-09 12:32:06.984: I/CHEOK(8926): E v.getLayoutParams().height = 89
10-09 12:32:07.000: I/CHEOK(8926): E v.getLayoutParams().height = 91
10-09 12:32:07.019: I/CHEOK(8926): E v.getLayoutParams().height = 91
10-09 12:32:07.039: I/CHEOK(8926): E v.getLayoutParams().height = -2
10-09 12:32:07.054: I/CHEOK(8926): E v.getLayoutParams().height = -2
新的高度每隔~20ms发生一次。因此,动画的FPS约为50fps。
当然,我不能直接删除requestLayout
,因为用户界面不会在屏幕上更新。
我在想,有没有什么改进的方法,可以使动画的FPS接近50fps?我见过一些商业产品有流畅的扩展/折叠的例子。所以,我想这是可以实现的。只是,我不确定具体怎么做。
我的布局代码如下。
<LinearLayout
android:clickable="true"
android:id="@+id/chart_linear_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:background="@drawable/dummy"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:orientation="horizontal">
<TextView
android:layout_width="0dp"
android:width="0dp"
android:layout_weight="0.6"
android:layout_height="wrap_content"
android:gravity="left"
android:textSize="20sp"
android:textColor="#ff000000"
android:text="Summary chart" />
<TextView
android:id="@+id/chart_price_text_view"
android:layout_width="0dp"
android:width="0dp"
android:layout_weight="0.4"
android:layout_height="wrap_content"
android:gravity="right"
android:textSize="20sp"
android:textColor="#ffF76D3C"
android:text="$2.99" />
</LinearLayout>
<TextView
android:visibility="gone"
android:id="@+id/chart_description_text_view"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:layout_marginBottom="10dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/currency_exchange_description"
android:textColor="#ff626262"
android:textSize="15sp" />
</LinearLayout>
我希望在chart_description_text_view
上执行流畅的动画。
Collapsing (During app startup)
Expanding (When user taps on it)
One of the "role models"我可以想到的是https://play.google.com/store/apps/details?id=ch.bitspin.timely.试着从其上调用以下对话框Shop菜单项。你会意识到他们的动画是多么流畅。不完全确定他们是如何实现的。
6 个回答
0 人赞同
你可以做平滑的动画 of View这样。
public class ViewAnimationUtils {
public static void expand(final View v) {
v.measure(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
final int targtetHeight = v.getMeasuredHeight();
v.getLayoutParams().height = 0;
v.setVisibility(View.VISIBLE);
Animation a = new Animation()
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
v.getLayoutParams().height = interpolatedTime == 1
? LayoutParams.WRAP_CONTENT
: (int)(targtetHeight * interpolatedTime);
v.requestLayout();
@Override
public boolean willChangeBounds() {
return true;
a.setDuration((int)(targtetHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
public static void collapse(final View v) {
final int initialHeight = v.getMeasuredHeight();
Animation a = new Animation()
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
if(interpolatedTime == 1){
v.setVisibility(View.GONE);
}else{
v.getLayoutParams().height = initialHeight - (int)(initialHeight * interpolatedTime);
v.requestLayout();
@Override
public boolean willChangeBounds() {
return true;
a.setDuration((int)(initialHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
Hope it will help you.
0 人赞同
The 最简单的做动画的方法是在你的xml中为你的线性布局添加以下内容。
android:animateLayoutChanges="true"
它工作得很好,直接使用安卓系统的默认动画。
0 人赞同
它很容易在视图上获得流畅的动画(扩展/折叠)。
public void expandOrCollapse(final View v,String exp_or_colpse) {
TranslateAnimation anim = null;
if(exp_or_colpse.equals("expand"))
anim = new TranslateAnimation(0.0f, 0.0f, -v.getHeight(), 0.0f);
v.setVisibility(View.VISIBLE);
else{
anim = new TranslateAnimation(0.0f, 0.0f, 0.0f, -v.getHeight());
AnimationListener collapselistener= new AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
@Override
public void onAnimationRepeat(Animation animation) {
@Override
public void onAnimationEnd(Animation animation) {
v.setVisibility(View.GONE);
anim.setAnimationListener(collapselistener);
// To Collapse
anim.setDuration(300);
anim.setInterpolator(new AccelerateInterpolator(0.5f));
v.startAnimation(anim);
并在你的代码中使用这个方法。我已经在TextView中使用了这个方法,并且经过了测试。你可以在这个方法中作为参数传递你的视图。
TextView tv=(TextView)findViewById(R.id.textview);
//TO Expand
expandOrCollapse(tv,"expand");
//TO Collapse
expandOrCollapse(tv,"collapse");
享受流畅的折叠和展开动画................。
0 人赞同
这里是kotlin方式的smoth动画。我在@TomEsterez的回答中加入了一些淡化动画。
fun expand(v: View) {
if (v.visibility == View.VISIBLE) return
val durations: Long
val matchParentMeasureSpec = View.MeasureSpec.makeMeasureSpec(
(v.parent as View).width,
View.MeasureSpec.EXACTLY
val wrapContentMeasureSpec = View.MeasureSpec.makeMeasureSpec(
View.MeasureSpec.UNSPECIFIED
v.measure(matchParentMeasureSpec, wrapContentMeasureSpec)
val targetHeight = v.measuredHeight
// Older versions of android (pre API 21) cancel animations for views with a height of 0.
v.layoutParams.height = 1
v.visibility = View.VISIBLE
durations = ((targetHeight / v.context.resources
.displayMetrics.density)).toLong()
v.alpha = 0.0F
v.visibility = View.VISIBLE
v.animate().alpha(1.0F).setDuration(durations).setListener(null)
val a: Animation = object : Animation() {
override fun applyTransformation(
interpolatedTime: Float,
t: Transformation
v.layoutParams.height =
if (interpolatedTime == 1f) LinearLayout.LayoutParams.WRAP_CONTENT else (targetHeight * interpolatedTime).toInt()
v.requestLayout()
override fun willChangeBounds(): Boolean {
return true
// Expansion speed of 1dp/ms
a.duration = durations
v.startAnimation(a)
fun collapse(v: View) {
if (v.visibility == View.GONE) return
val durations: Long
val initialHeight = v.measuredHeight
val a: Animation = object : Animation() {
override fun applyTransformation(
interpolatedTime: Float,
t: Transformation
if (interpolatedTime == 1f) {
v.visibility = View.GONE
} else {
v.layoutParams.height =
initialHeight - (initialHeight * interpolatedTime).toInt()
v.requestLayout()
override fun willChangeBounds(): Boolean {
return true
durations = (initialHeight / v.context.resources
.displayMetrics.density).toLong()
v.alpha = 1.0F
v.animate().alpha(0.0F).setDuration(durations)
.setListener(object : AnimatorListenerAdapter() {
override fun onAnimationEnd(animation: Animator) {
v.visibility = View.GONE
v.alpha = 1.0F
// Collapse speed of 1dp/ms
a.duration = durations
v.startAnimation(a)
然后,如果你愿意,你可以旋转Icon。(
// Expande
exImgHeader.animate().rotation(180f).start()
// Collapse
exImgHeader.animate().rotation(0f).start()
Result will be like this:
0 人赞同
在Github的SlideExpandibleList上有一个非常好的例子。
https://github.com/tjerkw/Android-SlideExpandableListView
希望这能帮助你实现流畅的动画和倒塌。
在这个例子中,它保存了扩展列表项的状态。因此,即使你向下滚动列表,它也不会让展开的列表项关闭。
在这个例子中,扩展或折叠事件是在Button上给出的,所以你需要改变它的List item父布局。
我附上了屏幕截图。
Hope this will help you.
0 人赞同
你可以在布局上应用CHANGING
的过渡。
你可以使用下面的扩展函数,它可以用来在android的任何布局上应用CHANGING
的过渡,通过传递以毫秒为单位的持续时间。
fun ViewGroup.setChangingTransition(animationDuration: Long) {
val layoutTransition = LayoutTransition()