使用 PullToRefreshLayout 时显示 Listview Header

Question

我指的是 this 刷新教程 ListView 而且效果很好。但问题是我在 ListView 上面有一个 Layout，所以当我运行我的应用程序 Listview 得到覆盖 Layout 时。为避免这种情况，我将布局设置为 header 到 ListView，但随后出现了一个新问题。当列表为空时 ListView Header 也不会显示。我还在 Adapter 中使用了 isEmpty() 仍然没有显示 Header.

Class:

        @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    LayoutInflater layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    activityView = layoutInflater.inflate(R.layout.groups_activity_layout, null, false);

    setContentView(activityView);



    /******************************************************************************/
    ViewGroup viewGroup = (ViewGroup) activityView;
    // As we're using a ListFragment we create a PullToRefreshLayout manually
    mPullToRefreshLayout = new PullToRefreshLayout(ItemscreenActivity.this);

    // We can now setup the PullToRefreshLayout
    ActionBarPullToRefresh.from(this)
    // We need to insert the PullToRefreshLayout into the Fragment's ViewGroup
    .insertLayoutInto(viewGroup)
    // Here we mark just the ListView and it's Empty View as pullable
    .theseChildrenArePullable(R.id.listView_demo_Items_gsal, android.R.id.empty).listener(this).setup(mPullToRefreshLayout);

    /******************************************************************************/

    arrayListOfAItems.clear();
    populateItemsArrayList(ItemscreenActivity.this);

    ItemsListWrtCnt++;
    // Getting the reference of Button and ListView
    listViewOfItems = (ListView) findViewById(R.id.listView_demo_Items_gsal);

    // Get Data in Adapter to set on ListView
    ItemscreenActivityAdapter = new ItemscreenAdapter(ItemscreenActivity.this, R.layout.group_screen_adapter_layout, arrayListOfAItems);
    listViewOfItems.setTextFilterEnabled(false);
    listViewOfItems.setScrollingCacheEnabled(false);
    listViewOfItems.setCacheColorHint(Color.TRANSPARENT);

    LayoutInflater inflater = getLayoutInflater();
    ViewGroup header = (ViewGroup) inflater.inflate(R.layout.group_activity_listview_header, listViewOfItems, false);
    listViewOfItems.addHeaderView(header, null, false);
    listViewOfItems.setEmptyView(header);
    listViewOfItems.setVisibility(View.VISIBLE);

    if (arrayListOfAItems.size() > 0) {
        // Set Adapter to ListView of group if there are Items
        ItemscreenActivityAdapter.notifyDataSetChanged();
        listViewOfItems.setAdapter(ItemscreenActivityAdapter);
        ItemsListWrtCnt--;
    } else {
        // Show Toast if no group to display
        Toast.makeText(ItemscreenActivity.this, "No Items", Toast.LENGTH_SHORT).show();
    }


}

XML:

<?xml version="1.0" encoding="utf-8"?>
<com.oi.demo.actionbarpulltorefresh.library.PullToRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layout_Items"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@android:color/white"
    android:orientation="vertical"
    tools:ignore="UselessParent" >

    <ListView
        android:id="@+id/listView_demo_Items_gsal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@+id/view_layout_footer_gsal"
        android:animationCache="false"
        android:background="@android:color/transparent"
        android:cacheColorHint="@android:color/transparent"
        android:divider="@null"
        android:persistentDrawingCache="scrolling"
        android:scrollbarStyle="outsideOverlay"
        android:scrollbars="vertical"
        android:scrollingCache="false"
        android:smoothScrollbar="true" />

    <View
        android:id="@+id/view_layout_footer_gsal"
        android:layout_width="fill_parent"
        android:layout_height="5dp"
        android:layout_gravity="bottom"
        android:background="#952d4a" />

</com.oi.demo.actionbarpulltorefresh.library.PullToRefreshLayout>

Answer 1

您需要做的只是将适配器设置在 if 条件之外。如：

if (arrayListOfAItems.size() > 0) {
    // Set Adapter to ListView of group if there are Items
    ItemscreenActivityAdapter.notifyDataSetChanged();

    ItemsListWrtCnt--;
} else {
    // Show Toast if no group to display
    Toast.makeText(ItemscreenActivity.this, "No Items", Toast.LENGTH_SHORT).show();
}

listViewOfItems.setAdapter(ItemscreenActivityAdapter);

至于显示 header 您需要以任何方式设置适配器。当您的列表为空时，未设置适配器，因此您看不到 header.

试试吧。一定会成功的。

使用 PullToRefreshLayout 时显示 Listview Header

Display Listview Header while using PullToRefreshLayout

android

listview

pull-to-refresh