如何在ListView中添加粘性标头？
Saa*_*aad 3 android listview header
我有一个listView,所以我想添加一个粘性标题,以便它粘贴到listView的顶部,当listView中的另一个类别开始时,一个不同的标题取代它的位置,就像联系人一样,其中"a"为一个Sticky标题位于顶部,直到"b"进来.是否有任何库可以做到？我使用自定义列表适配器来显示我的列表...
这是我的自定义适配器类
public class NewsRowAdapter extends ArrayAdapter<Item> {
private Activity activity;
private List<Item> items;
private Item objBean;
private int row;
private DisplayImageOptions options;
ImageLoader imageLoader;
public NewsRowAdapter(Activity act, int resource, List<Item> arrayList) {
super(act, resource, arrayList);
this.activity = act;
this.row = resource;
this.items = arrayList;
imageLoader = ImageLoader.getInstance();
File cacheDir1 = StorageUtils.getCacheDirectory(activity);
ImageLoaderConfiguration config = new
ImageLoaderConfiguration.Builder(activity)
.maxImageWidthForMemoryCache(600)
.maxImageHeightForMemoryCache(400)
.httpConnectTimeout(5000)
.httpReadTimeout(20000)
.threadPoolSize(3)
.threadPriority(Thread.MIN_PRIORITY + 3)
.denyCacheImageMultipleSizesInMemory()
.memoryCache(new UsingFreqLimitedMemoryCache(20000)) // You can pass your own memory cache implementation
.discCache(new TotalSizeLimitedDiscCache(cacheDir1, 30000)) // You can pass your own disc cache implementation
.defaultDisplayImageOptions(DisplayImageOptions.createSimple())
.build();
ImageLoader.getInstance().init(config);
// imageLoader = ImageLoader;
//
options = new DisplayImageOptions.Builder()
.showStubImage(R.drawable.icon2x)
.showImageForEmptyUrl(R.drawable.icon2x).cacheInMemory()
.cacheOnDisc().build();
//imageLoader = ImageLoader.getInstance();
}
@Override
public Item getItem(int position)
{
return items.get(position);
}
@Override
public int getCount()
{
return items.size();
}
@Override
public int getViewTypeCount()
{
return 3;
}
@Override
public int getItemViewType(int position)
{
Item item = items.get(position);
if (item.isHeader())
{
return TYPE_SECTION_HEADER;
}
else
{
return TYPE_LIST_ITEM;
}
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = convertView;
ViewHolder holder;
if (view == null) {
LayoutInflater inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(row, null);
holder = new ViewHolder();
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
if ((items == null) || ((position + 1) > items.size()))
return view;
objBean = items.get(position);
holder.tvName = (TextView) view.findViewById(R.id.title);
holder.tvId = (TextView) view.findViewById(R.id.id);
holder.tvFlag = (TextView) view.findViewById(R.id.flag);
holder.tvimageurl=(TextView) view.findViewById(R.id.imageurl);
holder.tvGender = (ImageView) view.findViewById(R.id.image);
//holder.tvAge = (TextView) view.findViewById(R.id.tvage);
holder.pbar = (ProgressBar) view.findViewById(R.id.pbar);
if (holder.tvName != null && null != objBean.getName()
&& objBean.getName().trim().length() > 0) {
holder.tvName.setText(Html.fromHtml(objBean.getName()));
}
if (holder.tvId != null && null != objBean.getId()
&& objBean.getId().trim().length() > 0) {
holder.tvId.setText(Html.fromHtml(objBean.getId()));
}
if (holder.tvFlag != null && null != objBean.getFlag()
&& objBean.getFlag().trim().length() > 0) {
holder.tvFlag.setText(Html.fromHtml(objBean.getFlag()));
}
if (holder.tvimageurl != null && null != objBean.getGender()
&& objBean.getFlag().trim().length() > 0) {
holder.tvimageurl.setText(Html.fromHtml(objBean.getGender()));
}
//if (holder.tvBDate != null && null != objBean.getBirthdate()
// && objBean.getBirthdate().trim().length() > 0) {
// holder.tvBDate.setText(Html.fromHtml(objBean.getBirthdate()));
//}
if (holder.tvGender != null) {
if (null != objBean.getGender()
&& objBean.getGender().trim().length() > 0) {
final ProgressBar pbar = holder.pbar;
imageLoader.displayImage(objBean.getGender(), holder.tvGender,
options, new ImageLoadingListener() {
@Override
public void onLoadingComplete() {
pbar.setVisibility(View.INVISIBLE);
}
@Override
public void onLoadingFailed() {
pbar.setVisibility(View.INVISIBLE);
}
@Override
public void onLoadingStarted() {
pbar.setVisibility(View.INVISIBLE);
}
});
} else {
holder.tvGender.setImageResource(R.drawable.icon2x);
}
}
return view;
}
public class ViewHolder {
public TextView tvimageurl;
public TextView tvFlag;
public TextView tvId;
public ProgressBar pbar;
public TextView tvName, tvCity, tvBDate, tvAge;
ImageView tvGender;
}
}
需要帮助.....
StickyHeader由于StickyListHeadersgit并不能完全符合我的需求,所以我在写自己的时候花了很长时间.然而,StickyListHeaders帮助我理解如何最终使它工作,因此StickyListHeaders值得一提的作者.
必须将许多东西放在一起才能使标头工作.
首先,声明以下内容
private TextView mStickyHeader;
private TextView mStickyHeader2;
private int mCurrentStickyHeaderSection;
在 onActivityCreated
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
...
mCurrentStickyHeaderSection = -1;
mStickyHeader = (TextView) getView().findViewById(R.id.textview_sticky_header_section);
mStickyHeader2 = (TextView) getView().findViewById(R.id.textview_sticky_header_section_2);
mListView = (ListView) getView().findViewById(R.id.listView_with_sticky_headers);
mListView.setOnScrollListener(new OnScrollListener() {
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
updateStickyHeader(firstVisibleItem);
}
@Override
public void onScrollStateChanged(AbsListView arg0, int arg1) {
// TODO Auto-generated method stub
}
});
我假设您已经编写了一个CustomAdapter带有索引的索引,并且只关注粘性标题.
以下方法包含了粘贴标头所需的全部内容.棘手的部分是确定是否firstVisibleItem是标题(pos = -1)和相应的部分.这部分可能需要您几次才能使其正常工作.
private void updateStickyHeader(int firstVisibleItem) {
// here is the tricky part. You have to determine pos and section
// pos is the position within a section pos = -1 means it's the header of the section
// you have to determine if firstVisibleItem is a header or not
// you also have to determine the section to which belongs the first item
int pos = whatIsThePositionOfTheItem[firstVisibleItem];
int section = whatIsTheSectionOfTheItem[firstVisibleItem];
if (section != mCurrentStickyHeaderSection) {
mStickyHeader.setText("Your_Previous_Section_Text");
mStickyHeader2.setText("Your_Next_Section_Text");
mCurrentStickyHeaderSection = section;
}
int stickyHeaderHeight = mStickyHeader.getHeight();
if (stickyHeaderHeight == 0) {
stickyHeaderHeight = mStickyHeader.getMeasuredHeight();
}
View SectionLastView = mListView.getChildAt(0);
if (SectionLastView != null && pos == -1 && SectionLastView.getBottom() <= stickyHeaderHeight) {
int lastViewBottom = SectionLastView.getBottom();
mStickyHeader.setTranslationY(lastViewBottom - stickyHeaderHeight);
mStickyHeader2.setTranslationY(lastViewBottom - stickyHeaderHeight + mStickyHeader.getHeight());
} else if (stickyHeaderHeight != 0) {
mStickyHeader.setTranslationY(0);
mStickyHeader2.setTranslationY(mStickyHeader.getHeight());
}
}
最后,布局必须包含a FrameLayout并且应该看起来像这样
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
//this textview is just a global title of your listview if you need one but can be remove
<TextView
android:id="@+id/textview_title"
style="?android:attr/listSeparatorTextViewStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="6dp"
android:paddingRight="6dp"
android:textIsSelectable="false" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<TextView
android:id="@+id/textview_sticky_header_section"
style="?android:attr/listSeparatorTextViewStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="6dp"
android:paddingRight="6dp"
android:textIsSelectable="false" />
<TextView
android:id="@+id/textview_sticky_header_section_2"
style="?android:attr/listSeparatorTextViewStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="6dp"
android:paddingRight="6dp"
android:textIsSelectable="false" />
</FrameLayout>
<ListView
android:id="@+id/listView_with_sticky_header"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fastScrollEnabled="true"
android:longClickable="true" >
</ListView>
</LinearLayout>
更新
正如在这里的评论中所要求的那样是对whatIsThePositionOfTheItem和的解释whatIsTheSectionOfTheItem.这些方法必须归还的position和section给定的项目.
在我的情况下,它很简单,我的数据已经包含section和position.实际上,我正在显示文本,并且该文本以section和开头position.所以我只是解析该文本来确定section和position.
对于其他人来说,很难举出一个例子,因为它实际上取决于你所展示的内容.但是长话短说whatIsThePositionOfTheItem并且whatIsTheSectionOfTheItem必须返回给定项目的位置和部分.你可能会需要填写一个表与position和section您的列表中的每个项目,并获得position与section从该表.
