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I would like a ScrollView to start all the way at the bottom. Any methods?

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  • 1
    I think its just scrollTo(), yea I just checked the dev docs for ScrollView. Easy peasy. Commented Jun 20, 2010 at 18:30

19 Answers 19

366

you should run the code inside the scroll.post like this:

scroll.post(new Runnable() { @Override public void run() { scroll.fullScroll(View.FOCUS_DOWN); } }); 
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6 Comments

there's some way without lose focus current element, when i do this i lose the focus of my current element (different from scrollview)
This is needed only in cases where the layout has not yet been measured and layouted (for example if you run it in onCreate). In cases like pressing a button, .post() is not needed.
If you don't want to focus on the ScrollView, you can use scroll.scrollTo(0, scroll.getHeight()); to jump to the bottom, or scroll.smoothScrollTo(0, scroll.getHeight()); for a smoother scroll
Isn't this code a possible memory leak? An anonymous Runnable is created that holds a reference to an activity (scroll)view. If the activity gets destroyed while the runnable is executing its task, it will leak a reference to the scrollview, no?
In Kotlin: scrollView.post { scrollView.fullScroll(View.FOCUS_DOWN) }
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340

scroll.fullScroll(View.FOCUS_DOWN) also should work.

Put this in a scroll.Post(Runnable run)

Kotlin Code

scrollView.post { scrollView.fullScroll(View.FOCUS_DOWN) } 

11 Comments

That doesn't seem to do anything, any suggestions? I tried it on onCreate and later in the onClick of a button.
It doesn't seems to work on changing orientation. Otherwise its working.
This doesn't work if the layout size has changed right before calling it. It needs to be posted instead.
This and below, won't work until you give some time to the view to inflate fully, just simplifying ademar answer. scrollView.postDelayed(new Runnable() { @Override public void run() { scrollView.fullScroll(View.FOCUS_UP // Or Down); } }, 1000);
scroll.fullScroll(View.FOCUS_DOWN) will lead to the change of focus. That will bring some strange behavior when there are more than one focusable views, e.g two EditText. Check another solution I provide at the bottom.
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135

scroll.fullScroll(View.FOCUS_DOWN) will lead to the change of focus. That will bring some strange behavior when there are more than one focusable views, e.g two EditText. There is another way for this question.

 View lastChild = scrollLayout.getChildAt(scrollLayout.getChildCount() - 1); int bottom = lastChild.getBottom() + scrollLayout.getPaddingBottom(); int sy = scrollLayout.getScrollY(); int sh = scrollLayout.getHeight(); int delta = bottom - (sy + sh); scrollLayout.smoothScrollBy(0, delta); 

This works well.

Kotlin Extension

fun ScrollView.scrollToBottom() { val lastChild = getChildAt(childCount - 1) val bottom = lastChild.bottom + paddingBottom val delta = bottom - (scrollY+ height) smoothScrollBy(0, delta) } 

Or if you want to further enhance to check whether it is already at the bottom before scrolling, you can do something like this:

 fun ScrollView.scrollToBottom() { val lastChild = children.lastOrNull() ?: return val bottom = lastChild.bottom + paddingBottom val currentY = height + scrollY val alreadyAtBottom = bottom <= currentY if (!alreadyAtBottom) { val delta = bottom - currentY smoothScrollBy(0, delta) } else { // already at bottom, do nothing } } 

10 Comments

So glad I didn't have to waste any more time on this. Just what I needed
This should have more upvotes. It is the best answer by far.
This is the best answer present here.
Tried everything else on this page, even the stuff way below this. This was the only thing that worked, and it doesn't cause my EditText to lose focus. Thank you.
If you need to scroll down while keyboard is showing up, combine this code with this library. Works like a charm.
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58

Sometimes scrollView.post doesn't work

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

BUT if you use scrollView.postDelayed, it will definitely work

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

4 Comments

thanks for the identification. postDelayed is better solution.
@Prashant :) :) :)
Just remember that you need to dispose of your Runnable when you finish the activity
how can one dispose of the runnable @FabioR
39

What worked best for me is

scroll_view.post(new Runnable() { @Override public void run() { // This method works but animates the scrolling // which looks weird on first load // scroll_view.fullScroll(View.FOCUS_DOWN); // This method works even better because there are no animations. scroll_view.scrollTo(0, scroll_view.getBottom()); } }); 

1 Comment

I tried this, but the algorithm here is wrong. Check my answer at the bottom please.
28

I increment to work perfectly.

 private void sendScroll(){ final Handler handler = new Handler(); new Thread(new Runnable() { @Override public void run() { try {Thread.sleep(100);} catch (InterruptedException e) {} handler.post(new Runnable() { @Override public void run() { scrollView.fullScroll(View.FOCUS_DOWN); } }); } }).start(); } 

Note

This answer is a workaround for really old versions of android. Today the postDelayed has no more that bug and you should use it.

5 Comments

Not above two, but this works well in my phone (LG JellyBean 4.1.2 Optimus G).
Why not use scrollView.postDelayed(runnable, 100)?
@MattWolfe at the time does not worked in some old versions of android. But today this answer is deprecated at all.
For the love of god, use scrollView.postDelayed(runnable, 100)! :)
I added a note @AlexLockwood I hope the people use the postDelayed :)
9

i tried that successful.

scrollView.postDelayed(new Runnable() { @Override public void run() { scrollView.smoothScrollTo(0, scrollView.getHeight()); } }, 1000); 

Comments

4

Here is some other ways to scroll to bottom

fun ScrollView.scrollToBottom() { // use this for scroll immediately scrollTo(0, this.getChildAt(0).height) // or this for smooth scroll //smoothScrollBy(0, this.getChildAt(0).height) // or this for **very** smooth scroll //ObjectAnimator.ofInt(this, "scrollY", this.getChildAt(0).height).setDuration(2000).start() } 

Using

If you scrollview already laid out

my_scroll_view.scrollToBottom() 

If your scrollview is not finish laid out (eg: you scroll to bottom in Activity onCreate method ...)

my_scroll_view.post { my_scroll_view.scrollToBottom() } 

Comments

3

When the view is not loaded yet, you cannot scroll. You can do it 'later' with a post or sleep call as above, but this is not very elegant.

It is better to plan the scroll and do it on the next onLayout(). Example code here:

https://stackoverflow.com/a/10209457/1310343

Comments

3

One thing to consider is what NOT to set. Make certain your child controls, especially EditText controls, do not have the RequestFocus property set. This may be one of the last interpreted properties on the layout and it will override gravity settings on its parents (the layout or ScrollView).

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1

Not exactly the answer to the question, but I needed to scroll down as soon as an EditText got the focus. However the accepted answer would make the ET also lose focus right away (to the ScrollView I assume).

My workaround was the following:

emailEt.setOnFocusChangeListener(new View.OnFocusChangeListener() { @Override public void onFocusChange(View v, boolean hasFocus) { if(hasFocus){ Toast.makeText(getActivity(), "got the focus", Toast.LENGTH_LONG).show(); scrollView.postDelayed(new Runnable() { @Override public void run() { scrollView.fullScroll(ScrollView.FOCUS_DOWN); } }, 200); }else { Toast.makeText(getActivity(), "lost the focus", Toast.LENGTH_LONG).show(); } } }); 

Comments

1

I actually found that calling fullScroll twice does the trick:

myScrollView.fullScroll(View.FOCUS_DOWN); myScrollView.post(new Runnable() { @Override public void run() { myScrollView.fullScroll(View.FOCUS_DOWN); } }); 

It may have something to do with the activation of the post() method right after performing the first (unsuccessful) scroll. I think this behavior occurs after any previous method call on myScrollView, so you can try replacing the first fullScroll() method by anything else that may be relevant to you.

Comments

0

Using there is another cool way to do this with Kotlin coroutines. The advantage of using a coroutine opposed to a Handler with a runnable (post/postDelayed) is that it does not fire up an expensive thread to execute a delayed action.

launch(UI){ delay(300) scrollView.fullScroll(View.FOCUS_DOWN) } 

It is important to specify the coroutine's HandlerContext as UI otherwise the delayed action might not be called from the UI thread.

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0

In those case were using just scroll.scrollTo(0, sc.getBottom()) don't work, use it using scroll.post

Example:

scroll.post(new Runnable() { @Override public void run() { scroll.fullScroll(View.FOCUS_DOWN); } }); 

Comments

0

One possible reason of why scroll.fullScroll(View.FOCUS_DOWN) might not work even wrapped in .post() is that the view is not laid out. In this case View.doOnLayout() could be a better option:

scroll.doOnLayout(){ scroll.fullScroll(View.FOCUS_DOWN) } 

Or, something more elaborated for the brave souls: https://chris.banes.dev/2019/12/03/suspending-views/

Comments

0

A combination of all answers did the trick for me:

Extension Function PostDelayed

private fun ScrollView.postDelayed( time: Long = 325, // ms block: ScrollView.() -> Unit ) { postDelayed({block()}, time) } 

Extension Function measureScrollHeight

fun ScrollView.measureScrollHeight(): Int { val lastChild = getChildAt(childCount - 1) val bottom = lastChild.bottom + paddingBottom val delta = bottom - (scrollY+ height) return delta } 

Extension Function ScrolltoBottom

fun ScrollView.scrollToBottom() { postDelayed { smoothScrollBy(0, measureScrollHeight()) } } 

Be aware that the minimum delay should be at least 325ms or the scrolling will be buggy (not scrolling to the entire bottom). The larger your delta between the current height and the bottom is, the larger should be the delayed time.

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0

Some people here said that scrollView.post didn't work.

If you don't want to use scrollView.postDelayed, another option is to use a listener. Here is what I did in another use case :

ViewTreeObserver.OnPreDrawListener viewVisibilityChanged = new ViewTreeObserver.OnPreDrawListener() { @Override public boolean onPreDraw() { if (my_view.getVisibility() == View.VISIBLE) { scroll_view.smoothScrollTo(0, scroll_view.getHeight()); } return true; } }; 

You can add it to your view this way :

my_view.getViewTreeObserver().addOnPreDrawListener(viewVisibilityChanged); 

Comments

0

If your minimum SDK is 29 or upper you could use this:

View childView = findViewById(R.id.your_view_id_in_the_scroll_view) if(childView != null){ scrollview.post(() -> scrollview.scrollToDescendant(childView)); } 

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-1

This works instantly. Without delay.

// wait for the scroll view to be laid out scrollView.post(new Runnable() { public void run() { // then wait for the child of the scroll view (normally a LinearLayout) to be laid out scrollView.getChildAt(0).post(new Runnable() { public void run() { // finally scroll without animation scrollView.scrollTo(0, scrollView.getBottom()); } } } } 

Comments

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