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How to scroll to bottom in a ScrollView on activity startup

I am displaying some data in a ScrollView. On activity startup (method onCreate) I fill the ScrollView with data and want to scroll to the bottom.

I tried to use getScrollView().fullScroll(ScrollView.FOCUS_DOWN). This works when I make it as an action on button click but it doesn't work in the onCreate method.

Is there any way how to scroll the ScrollView to the bottom on activity startup? That means the view is already scrolled to the bottom when first time displayed.

This also explains why I was getting 0 all the time when I was trying to use getMeasuredWidth while initialising my own subclass of a ScrollView.

P
Palo

It needs to be done as following:

    getScrollView().post(new Runnable() {

        @Override
        public void run() {
            getScrollView().fullScroll(ScrollView.FOCUS_DOWN);
        }
    });

This way the view is first updated and then scrolls to the "new" bottom.


I'm trying exactly this but it doesn't seem to work still... are you calling the above code in onCreate of the containing Activity?
Instead post() use postDelayed() with 100ms delay. it will work from any activitys life-cycle point.
C
Community

Put the following code after your data is added:

final ScrollView scrollview = ((ScrollView) findViewById(R.id.scrollview));
scrollview.post(new Runnable() {
    @Override
    public void run() {
        scrollview.fullScroll(ScrollView.FOCUS_DOWN);
    }
});

For me this only worked with a postDelayed instead of post. Just 100 milliseconds of delay.
Perfect. Of course with combo with scrollview.fullScroll(ScrollView.FOCUS_UP);
S
Seraphim's

This works for me:

scrollview.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        scrollview.post(new Runnable() {
            public void run() {
                scrollview.fullScroll(View.FOCUS_DOWN);
            }
        });
    }
});

Best answer for this question so far. Lots of other approaches are conditional but this one is awesome n works super fine :)
T
Tam Dao

You can do this in layout file:

                android:id="@+id/listViewContent"
                android:layout_width="wrap_content"
                android:layout_height="381dp" 
                android:stackFromBottom="true"
                android:transcriptMode="alwaysScroll">

M
Makvin
 scrollView.postDelayed(new Runnable() {
        @Override
        public void run() {
            scrollView.fullScroll(ScrollView.FOCUS_DOWN);
        }
    },1000);

F
F.O.O

Try this

    final ScrollView scrollview = ((ScrollView) findViewById(R.id.scrollview));
    scrollview.post(new Runnable() {
       @Override
       public void run() {
         scrollview.fullScroll(ScrollView.FOCUS_DOWN);
       }
    });

L
LEMUEL ADANE

Right after you append data to the view add this single line:

yourScrollview.fullScroll(ScrollView.FOCUS_DOWN);

J
Jacob

This is the best way of doing this.

scrollView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {
            scrollView.post(new Runnable() {
                @Override
                public void run() {
                    scrollView.fullScroll(View.FOCUS_DOWN);
                }
            });
        }
});

R
Ramzy Hassan

After initializing your UI component and fill it with data. add those line to your on create method

Runnable runnable=new Runnable() {
        @Override
        public void run() {
            scrollView.fullScroll(ScrollView.FOCUS_DOWN);
        }
    };
    scrollView.post(runnable);