Listview create all elements instead of visible ones

Question

I have an issue which I didn't found any solutions on stackoverflow (or anywhere else so far).

Summary :

I have scrollview and inside of it a ListView with visibility gone (Can switch with a TextView).

When I set the adapter content, in my activity the onScroll get call with 4 visibles Item but the getView of the adapter get call for the whole dataSet (181 items) which bring a lot of performance issues / imageref_ashmem create failed ... (Of course remove image loading remove fail of creation but well :D)

=== Activity ===

Result of Activity in onScroll

firstVisibleItem    0   
visibleItemCount    4   
totalItemCount  181

=== Layout extract ===

<ScrollView 
    android:id="@+id/UserProfileView_ScrollView"       
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:fillViewport="true"
    android:background="#00FFFFFF" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#00FFFFFF" >

        <RelativeLayout 
            android:id="@+moreDetails/UserProfileView_BottomLayout"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_below="@+profile/UserProfileView_MoreDetails"
            android:background="#FFFFFFFF" >

            <TextView
                android:id="@+id/UserProfileView_About"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_centerHorizontal="true"
                android:layout_centerVertical="true"
                android:gravity="center"
                android:textAppearance="?android:attr/textAppearanceLarge"
                android:textColor="#ff111111"
                android:visibility="gone" />

            <ListView
                android:id="@+id/UserProfileView_MoreDetails_ListView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_alignParentTop="true"
                android:footerDividersEnabled="false"
                android:divider="@color/unactivatedLightGray"
                android:dividerHeight="1dp"
                android:listSelector="@android:color/transparent"
                android:visibility="gone" />

        </RelativeLayout>

    </RelativeLayout>

</ScrollView>

The height of the BottomLayout is set to 3/4 of the width of the screen programmatically.

=== Adapter ===

public class CommonAdapter extends BaseAdapter {

public List<Common>     list;
private LayoutInflater      inflater;
private AQuery              aq;

public CommonAdapter(Context context, List<Common> list) {
    this.inflater = LayoutInflater.from(context);
    this.list = list;
    this.aq = new AQuery(context);
}

@Override
public int getCount() {
    return list.size();
}

@Override
public Object getItem(int position) {
    return list.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

private class ViewHolder {
    ImageView       thumbImg;
    TextView            name;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ViewHolder holder;

    if (convertView == null) {
        holder = new ViewHolder();
        convertView = inflater.inflate(R.layout.list_view_item, null);
        holder.thumbImg     = (ImageView) convertView.findViewById(R.id.CommonCell_Thumb);
        holder.name = (TextView) convertView.findViewById(R.id.CommonCell_Name);
        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }

    Common obj = list.get(position);

    if (list.get(position).getPicture() != null)
        aq.id(holder.thumbImg).image(obj.getPicture());
    else
        aq.id(holder.thumbImg).image(Util.Thumb(list.get(position).getId()), options);
    holder.name.setText(obj.getName());

    return convertView;
}
}

EDIT : Every time I scroll, the whole dataset it parse again, so 181 call to getView.

dont place a ListView inside a ScrollView, why are you doing so? — pskink, May 08 '14 at 03:51
@EngrWaseemArain hum ... the problem is quite simple in fact. I have only 4 elements visible while getView is called for every position, from 0 to 181. — Atheryl, May 08 '14 at 03:54
@pskink For UI issue I don't have any other way to make it. Moreover I would like to find out what happen, it doesn't seems to be normal either. Also why not ? It works perfectly and no extra code to make it works. Unless there is a clear reason why my problem is related to this point. — Atheryl, May 08 '14 at 03:55
@Atheryl it happens because the ScrollView will expand to fit all the content, and the ListView will expand to fit the ScrollView. — panini, May 08 '14 at 04:09
@Atheryl see http://blog.mettletech.co/wp/blog/listview-inside-a-scrollview/ http://stackoverflow.com/questions/3495890/how-can-i-put-a-listview-into-a-scrollview-without-it-collapsing http://kennethflynn.wordpress.com/2012/09/12/putting-android-listviews-in-scrollviews/ and many more... — pskink, May 08 '14 at 04:14
@panini hummm I expected to avoid this by set the ListView size. Well ... kind of ... I will try something since the activity seems to know what elements are visible and then accept the evidence that I might need to change ... Thanks for the quick reply. — Atheryl, May 08 '14 at 04:22
I fixed the issue by set the ListView to an arbitrary Height. — Atheryl, May 08 '14 at 04:29

score 1 · Answer 1 · answered May 08 '14 at 04:04

1

I assume your aq.id(stuff) loads an image asyncronous.

If so, check your layout/list_view_item.xml it's height is probably set to wrap_content and the ImageView also has no fixed height. Meaning while loading the image this row has a zero or very small height. Therefore all 182 rows fit into the ListView at once and getView() gets called for every single one.

Set a fixed height or minHeight for every row or the ImageView the ListView will only call getView() for as many rows fit into the ListView.

Hope this helps

answered May 08 '14 at 04:04

Su-Au Hwang

4,131
16
23

Unfortunately my image in the cell layout is set to 60dp. Meanwhile the relativeLayout contain it is wrap_content by I will set fixed to give a try. The cell itself is 70dp whatever the content. – Atheryl May 08 '14 at 04:09
On a side note having a ScrollView or ListView have it's height set to `wrap_content` makes no sense, i don't think it matters in this case though, as android will automatically set it to `match_parent` when detected (don't take my word for it). – Su-Au Hwang May 08 '14 at 04:12
Actually I didn't put a lot of other part of the layout. I have several constraint to make it fill the screen and animate resizing some part depending on actions. Meanwhile I will rethink about redo this part since lot of people advice so. – Atheryl May 08 '14 at 04:15
Because of the animation and resizing the views all the rows re-inflated I think. Better choice you have decided. Check it after removing those parts. – Sripathi May 08 '14 at 05:58
Now it's working perfectly with the height set. @panini found out. Listview inside scrollview consider it can show infinity of elements which result on what you say (Same as if no height). Thanks for your help. – Atheryl May 10 '14 at 14:04

score 1 · Accepted Answer · answered May 08 '14 at 04:31

I fixed the issue by set the ListView to an arbitrary Height.

<ListView
    android:id="@+id/UserProfileView_MoreDetails_ListView"
    android:layout_width="match_parent"
    android:layout_height="1080dp"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:footerDividersEnabled="false"
    android:divider="@color/unactivatedLightGray"
    android:dividerHeight="1dp"
    android:listSelector="@android:color/transparent"
    android:visibility="gone" />

score 0 · Answer 3 · answered Sep 25 '20 at 18:22

0

If ListView or RecyclerView used in ScrollView, All items will initiate at the same time.

answered Sep 25 '20 at 18:22

Hassan Alizadeh

99
1
8

Listview create all elements instead of visible ones

3 Answers3