在iOS中,有一个非常简单和强大的工具来动画添加和删除UITableView行,这是一个来自youtube视频的剪辑,显示默认动画。注意周围的行如何折叠到已删除的行上。这个动画帮助用户跟踪列表中发生了什么变化,以及当数据发生变化时他们正在查看列表中的哪个位置。
Since I've been developing on Android I've found no equivalent facility to animate individual rows in a TableView. Calling notifyDataSetChanged() on my Adapter causes the ListView to immediately update its content with new information. I'd like to show a simple animation of a new row pushing in or sliding out when the data changes, but I can't find any documented way to do this. It looks like LayoutAnimationController might hold a key to getting this to work, but when I set a LayoutAnimationController on my ListView (similar to ApiDemo's LayoutAnimation2) and remove elements from my adapter after the list has displayed, the elements disappear immediately instead of getting animated out.
我还尝试了如下方法,在移除单个项目时将其动画化:
@Override
protected void onListItemClick(ListView l, View v, final int position, long id) {
Animation animation = new ScaleAnimation(1, 1, 1, 0);
animation.setDuration(100);
getListView().getChildAt(position).startAnimation(animation);
l.postDelayed(new Runnable() {
public void run() {
mStringList.remove(position);
mAdapter.notifyDataSetChanged();
}
}, 100);
}
但是,动画行周围的行不会移动位置,直到调用notifyDataSetChanged()时它们跳转到新位置。一旦元素被放置,ListView似乎不会更新它的布局。
虽然写我自己的ListView的实现/分支已经越过我的脑海,这似乎不应该是那么困难的事情。
谢谢!
我用另一种方法来做而不需要操作列表视图。不幸的是,常规的Android动画似乎操纵行内容,但实际上是无效的缩小视图。所以,首先考虑这个处理程序:
private Handler handler = new Handler() {
@Override
public void handleMessage(Message message) {
Bundle bundle = message.getData();
View view = listView.getChildAt(bundle.getInt("viewPosition") -
listView.getFirstVisiblePosition());
int heightToSet;
if(!bundle.containsKey("viewHeight")) {
Rect rect = new Rect();
view.getDrawingRect(rect);
heightToSet = rect.height() - 1;
} else {
heightToSet = bundle.getInt("viewHeight");
}
setViewHeight(view, heightToSet);
if(heightToSet == 1)
return;
Message nextMessage = obtainMessage();
bundle.putInt("viewHeight", (heightToSet - 5 > 0) ? heightToSet - 5 : 1);
nextMessage.setData(bundle);
sendMessage(nextMessage);
}
将这个集合添加到您的List适配器:
private Collection<Integer> disabledViews = new ArrayList<Integer>();
并添加
public boolean isEnabled(int position) {
return !disabledViews.contains(position);
}
接下来,无论你想要隐藏一行的地方,添加这个:
Message message = handler.obtainMessage();
Bundle bundle = new Bundle();
bundle.putInt("viewPosition", listView.getPositionForView(view));
message.setData(bundle);
handler.sendMessage(message);
disabledViews.add(listView.getPositionForView(view));
就是这样!你可以通过改变一次缩小高度的像素数来改变动画的速度。不是很复杂,但很管用!
正如我在我的网站上解释了我的方法,我分享了链接。不管怎样,我们的想法是创建位图
通过getdrawingcache .有两个位图和动画下位图来创建移动效果
请参阅以下代码:
listView.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
public void onItemClick(AdapterView<?> parent, View rowView, int positon, long id)
{
listView.setDrawingCacheEnabled(true);
//listView.buildDrawingCache(true);
bitmap = listView.getDrawingCache();
myBitmap1 = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), rowView.getBottom());
myBitmap2 = Bitmap.createBitmap(bitmap, 0, rowView.getBottom(), bitmap.getWidth(), bitmap.getHeight() - myBitmap1.getHeight());
listView.setDrawingCacheEnabled(false);
imgView1.setBackgroundDrawable(new BitmapDrawable(getResources(), myBitmap1));
imgView2.setBackgroundDrawable(new BitmapDrawable(getResources(), myBitmap2));
imgView1.setVisibility(View.VISIBLE);
imgView2.setVisibility(View.VISIBLE);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
lp.setMargins(0, rowView.getBottom(), 0, 0);
imgView2.setLayoutParams(lp);
TranslateAnimation transanim = new TranslateAnimation(0, 0, 0, -rowView.getHeight());
transanim.setDuration(400);
transanim.setAnimationListener(new Animation.AnimationListener()
{
public void onAnimationStart(Animation animation)
{
}
public void onAnimationRepeat(Animation animation)
{
}
public void onAnimationEnd(Animation animation)
{
imgView1.setVisibility(View.GONE);
imgView2.setVisibility(View.GONE);
}
});
array.remove(positon);
adapter.notifyDataSetChanged();
imgView2.startAnimation(transanim);
}
});
要理解图像,请参阅这里
谢谢。