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java - Scroll up does not work with SwipeRefreshLayout in Listview

I want to implement scroll to refresh functionality with a listView. Also there are other view elements in the same layout file which are displayed if the list is empty. Here is my layout file. The problem is that when I scroll down and then try to scroll up, instead of scrolling all the way to the top and then refreshing it just refreshes there and scroll up is not working.

<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/swipe_container"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="64dp"
        android:paddingLeft="16dp"
        android:paddingRight="16dp" >

        <ImageView
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:layout_alignParentLeft="true"
            android:layout_centerVertical="true"
            android:src="@drawable/inbox_empty" />

        <TextView
            android:id="@+id/noEventsText"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginLeft="16dp"
            android:layout_toRightOf="@+id/noEventsIcon" />

        <View
            android:id="@+id/divider"
            android:layout_width="match_parent"
            android:layout_height="1px"
            android:layout_alignParentBottom="true"
            android:layout_marginLeft="4dp"
            android:layout_marginRight="4dp"
            android:background="@color/dividerOnBlack" />
    </RelativeLayout>

    <ListView
        android:id="@+id/list_items"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:cacheColorHint="@android:color/transparent"
        android:choiceMode="multipleChoice"
        android:descendantFocusability="afterDescendants"
        android:divider="@android:color/transparent"
        android:dividerHeight="0px"
        android:scrollbars="none" />
</LinearLayout>

</android.support.v4.widget.SwipeRefreshLayout>

This is my onScroll method.

@Override
public void onScroll(AbsListView view,int firstVisibleItem,int visibleItemCount,int totalItemCount) {
    // If the total item count is zero and the previous isn't, assume the
    // list is invalidated and should be reset back to initial state
    if (totalItemCount < previousTotalItemCount) {
        this.currentPage = this.startingPageIndex;
        this.previousTotalItemCount = totalItemCount;
        if (totalItemCount == 0) { this.loading = true; } 
    }

    // If it's still loading, we check to see if the dataset count has
    // changed, if so we conclude it has finished loading and update the current page
    // number and total item count.
    if (loading && (totalItemCount > previousTotalItemCount)) {
        loading = false;
        previousTotalItemCount = totalItemCount;
        currentPage++;
    }

    // If reverse then the firstVisibleItem is calculated wrong
    if (reverse) {
        firstVisibleItem = totalItemCount - firstVisibleItem;
    }
    // If it isn't currently loading, we check to see if we have breached
    // the visibleThreshold and need to reload more data.
    // If we do need to reload some more data, we execute onLoadMore to fetch the data.
    if (!loading && (totalItemCount - visibleItemCount)<=(firstVisibleItem + visibleThreshold)) {
        onLoadMore(currentPage + 1, totalItemCount);
        loading = true;
    }
}
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1 Answer

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by (71.8m points)

In order for SwipeRefreshLayout to work, it needs to be the direct parent of your ListView, and the ListView should be the first active child view of the SwipeRefreshLayout.

The documentation for SwipeRefreshLayout says that the ListView should be the only child, but it is okay if it has more than one child as long as the ListView is first. This means, for instance, that SwipeRefreshLayout will work fine if you are using an adapter with a view for "empty". For example:

<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/swipe_refresh"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".NearbyJobsActivity$PlaceholderFragment">

    <ListView
        android:id="@android:id/list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:divider="@color/list_divider"
        android:dividerHeight="1dp"
        android:listSelector="@drawable/list_row_selector" />

    <TextView
        android:id="@android:id/empty"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center" />

</android.support.v4.widget.SwipeRefreshLayout>

If you can manage this sort of layout, then SwipeRefreshLayout will work fine and you won't need any of the workarounds listed in other answers.

My own problem was that that I was loading my ListView as a Fragment, so I actually had:

<SwipeRefreshLayout>

    <FrameLayout>           )
         <ListView/>         fragment
         <TextView/>        /
    </FrameLayout>          )

</SwipeRefreshLayout>

So the SwipeRefreshLayout was choosing the FrameLayout as it's "target" and its default canChildScrollUp() implementation was always returning false. Once I moved the SwipeRefreshLayout inside the Fragment, everything started working correctly.

<FrameLayout>

    <SwipeRefreshLayout>    )
         <ListView/>         fragment
         <TextView/>        /
    </SwipeRefreshLayout>   )

</FrameLayout>

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