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How can I get my ListView to scroll?

开发者 https://www.devze.com 2023-02-16 18:53 出处:网络
I have a quite complex View build-up, and as a part of that, I have a ListView inside a LinearLayout within a ScrollView (and quite a lot more components, but they do not matter in this issue).

I have a quite complex View build-up, and as a part of that, I have a ListView inside a LinearLayout within a ScrollView (and quite a lot more components, but they do not matter in this issue).

Now the whole activity scrolls nicely as it should, but the ListView has a limited height, and when the Items inside it surpass the height, the disappear of my screen. I've tried to place the ListView inside it's own ScrollView, but this doesn't work. When I try to scroll on the ListView, the main ScrollView is selected and my screen scrolls instead of the ListView.

My question may sound easy, but I haven't been able to fix this... Is it p开发者_如何学Goossible to make the ListView scrollable aswell?

The relevant XML:

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

    <LinearLayout android:id="@+id/GlobalLayout" 
                  android:layout_width="fill_parent"
                  android:layout_height="fill_parent"
                  android:orientation="vertical" >

        <ListView android:id="@+id/EndpointList"
                  android:choiceMode="multipleChoice"
                  android:layout_height="175dip"
                  android:layout_width="fill_parent" />

    </LinearLayout>

</ScrollView>


Instead of ListView with other layouts inside ScrollView create one ListView with header and footer.

Add views that should be above ListView as a header:

addHeaderView(View v)

and that below as a footer:

addFooterView(View v)

Put everything what should be above ListView to header of ListView and the same with footer.

    LayoutInflater inflater = LayoutInflater.from(this);
    mTop    = inflater.inflate(R.layout.view_top, null);
    mBottom = inflater.inflate(R.layout.view_bottom, null);

    list.addHeaderView(mTop);
    list.addFooterView(mBottom);
    // add header and footer before setting adapter
    list.setAdapter(mAdapter);

In result you'll get one scrollable view.


Actually, the way that I have it set up is really working... Placing a ListView in a LinearLayout within a ScrollView. Just avoid that the ListView is the direct child of the ScrollView, and it will work out just fine...

Just be aware that if there aren't enough items in the ListView to fill it so it goes 'off screen', that it won't scroll (kind of logically though). Also note that when you have enough items to scroll through, you need to keep pressing on an item in the ListView to make it scroll, and half of the time, focus is given to the global scrollview in stead of the ListView... To avoid this (most of the time), keep pressing on the most top or most down item, depending on which way you want to scroll.This will optimize your chance to get focus on your ListView.

I've made a video that it is possible, am uploading it now to YouTube...

Video is http://www.youtube.com/watch?v=c53oIg_3lKY. The quality is kinda bad, but it proves my point.

Just for a global overview, I used the ScrollView to be able to scroll my entire activity, the LinearLayout for the Activity's layout, and the ListView to, well, make the list...


I would like to just note something for the video

The listview is working once every x touches not because you placed it inside a linearlayout but because you are touching the the divider...

the scrollview will then consider that the place you touched does not have children to dispatch the motionevent to... so it calls the super.dispatchTouchEvent which is in this case the View.dispatchTouchView hence the listview.onTouchEvent.

When you touch inside a row the scrollview which is really a viewgroup will send the dispatch to the children in your case the textview and never calls the one of the view so the listview do not scroll.

Hope my explanation was clear enough to point out why is it not working.

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