假设我有一个垂直线性布局:
[v1]
[v2]
默认情况下，v1已经可见= GONE。我想用一个展开动画显示v1，同时下推v2。
我是这样做的:
Animation a = new Animation()
{
int initialHeight;
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
final int newHeight = (int)(initialHeight * interpolatedTime);
v.getLayoutParams().height = newHeight;
v.requestLayout();
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
initialHeight = height;
}
@Override
public boolean willChangeBounds() {
return true;
}
};
但是用这个解决方案，当动画开始时我有一个眨眼。我认为这是由于v1在应用动画之前显示全尺寸。
用javascript，这是一行jQuery!android有什么简单的方法吗?
平滑动画请使用Handler运行方法.....享受展开/折叠动画
class AnimUtils{
public void expand(final View v) {
int ANIMATION_DURATION=500;//in milisecond
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;
}
};
// 1dp/ms
a.setDuration(ANIMATION_DURATION);
// a.setDuration((int)(targtetHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
}
public 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;
}
};
// 1dp/ms
a.setDuration(ANIMATION_DURATION);
// a.setDuration((int)(initialHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
}
}
使用下面的代码调用:
private void setAnimationOnView(final View inactive ) {
//I am applying expand and collapse on this TextView ...You can use your view
//for expand animation
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
new AnimationUtililty().expand(inactive);
}
}, 1000);
//For collapse
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
new AnimationUtililty().collapse(inactive);
//inactive.setVisibility(View.GONE);
}
}, 8000);
}
其他解决方案是:
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);
}
这是我的解决方案，我的ImageView从100%增长到200%，并返回到原来的大小，使用res/anim/文件夹中的两个动画文件
anim_grow.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:interpolator="@android:anim/accelerate_interpolator">
<scale
android:fromXScale="1.0"
android:toXScale="2.0"
android:fromYScale="1.0"
android:toYScale="2.0"
android:duration="3000"
android:pivotX="50%"
android:pivotY="50%"
android:startOffset="2000" />
</set>
anim_shrink.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:interpolator="@android:anim/accelerate_interpolator">
<scale
android:fromXScale="2.0"
android:toXScale="1.0"
android:fromYScale="2.0"
android:toYScale="1.0"
android:duration="3000"
android:pivotX="50%"
android:pivotY="50%"
android:startOffset="2000" />
</set>
发送一个ImageView到setAnimationGrowShrink()方法
ImageView img1 = (ImageView)findViewById(R.id.image1);
setAnimationGrowShrink(img1);
setAnimationGrowShrink()方法:
private void setAnimationGrowShrink(final ImageView imgV){
final Animation animationEnlarge = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.anim_grow);
final Animation animationShrink = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.anim_shrink);
imgV.startAnimation(animationEnlarge);
animationEnlarge.setAnimationListener(new AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {}
@Override
public void onAnimationRepeat(Animation animation) {}
@Override
public void onAnimationEnd(Animation animation) {
imgV.startAnimation(animationShrink);
}
});
animationShrink.setAnimationListener(new AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {}
@Override
public void onAnimationRepeat(Animation animation) {}
@Override
public void onAnimationEnd(Animation animation) {
imgV.startAnimation(animationEnlarge);
}
});
}
我看到这个问题很受欢迎，所以我发布了我的实际解决方案。主要的优点是你不需要知道扩展的高度来应用动画，一旦视图被扩展，它会在内容改变时适应高度。这对我来说很有效。
public static void expand(final View v) {
int matchParentMeasureSpec = View.MeasureSpec.makeMeasureSpec(((View) v.getParent()).getWidth(), View.MeasureSpec.EXACTLY);
int wrapContentMeasureSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
v.measure(matchParentMeasureSpec, wrapContentMeasureSpec);
final int targetHeight = v.getMeasuredHeight();
// Older versions of android (pre API 21) cancel animations for views with a height of 0.
v.getLayoutParams().height = 1;
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)(targetHeight * interpolatedTime);
v.requestLayout();
}
@Override
public boolean willChangeBounds() {
return true;
}
};
// Expansion speed of 1dp/ms
a.setDuration((int)(targetHeight / 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;
}
};
// Collapse speed of 1dp/ms
a.setDuration((int)(initialHeight / v.getContext().getResources().getDisplayMetrics().density));
v.startAnimation(a);
}
正如@Jefferson在评论中提到的，你可以通过改变动画的持续时间(以及速度)来获得更流畅的动画。目前，它已设置为1dp/ms的速度
我今天也遇到了同样的问题，我想这个问题的真正解决方案是这样的
<LinearLayout android:id="@+id/container"
android:animateLayoutChanges="true"
...
/>
您必须为所有涉及移位的最顶层布局设置此属性。如果你现在将一个布局的可见性设置为GONE，另一个将在消失的布局释放它时占据空间。会有一个默认的动画，这是某种“淡出”，但我认为你可以改变这个-但最后一个我没有测试，现在。
如果在RecyclerView项目中使用这个，在onBindViewHolder中设置视图的可见性来展开/折叠，并调用notifyItemChanged(position)来触发转换。
override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
...
holder.list.visibility = data[position].listVisibility
holder.expandCollapse.setOnClickListener {
data[position].listVisibility = if (data[position].listVisibility == View.GONE) View.VISIBLE else View.GONE
notifyItemChanged(position)
}
}
如果你在onBindViewHolder中执行昂贵的操作，你可以使用notifyItemChanged(位置，有效载荷)优化部分更改
private const val UPDATE_LIST_VISIBILITY = 1
override fun onBindViewHolder(holder: ItemViewHolder, position: Int, payloads: MutableList<Any>) {
if (payloads.contains(UPDATE_LIST_VISIBILITY)) {
holder.list.visibility = data[position].listVisibility
} else {
onBindViewHolder(holder, position)
}
}
override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
...
holder.list.visibility = data[position].listVisibility
holder.expandCollapse.setOnClickListener {
data[position].listVisibility = if (data[position].listVisibility == View.GONE) View.VISIBLE else View.GONE
notifyItemChanged(position, UPDATE_LIST_VISIBILITY)
}
}
