Develop Reference

How to center a layout inside a scrollView on click?

So I have this layout here:
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/scrollView"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="#+id/instructions">
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="Sample text 1"/>
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="Sample text 2"/>
<TextView
android:id="#+id/textView3"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="Sample text 3"/>
</LinearLayout>
</ScrollView>
(I just made it up to textView3 for simplicity's sake, but say there's more and the scrollView is scrollable) then there is a button outside this scrollView. Every time the button is clicked the scrollView scrolls and centers the view to the next textView. How can I achieve this?
I've tried getting the height of the views then adding it up to use on the scrollView.scrollTo(y), but retrieving the height gave me lots of problems, I used the ViewTreeObserver process but I couldn't retrieve the height inside the
.addOnGlobalLayoutListener(New ViewTreeObserver...
and place it on a variable. but I failed with this method. What am I doing wrong? or are there any easier approach?

You might consider using RecyclerView and add new items to the list and then call the scrollToPosition(position) function to scroll to the latest one.
Don't forget to add paddingBottom to the RecyclerView to be able to scroll the last view into to center. (Use the screenHeight / 2 for the paddingBottom)

ScrollView not sizing itself correctly

I'm trying to get a ScrollView to take up as much screen space as it needs until it would start pushing items below (outside) it off the screen, then it needs to stop expanding and become scrolly.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#ff0000"
>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable"
/>
<!--
android:text="just one line"
-->
</ScrollView>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Button"
/>
</LinearLayout>
As it is above the ScrollView fills the entire screen height and pushes the button off the bottom of the screen.
If I add android:layout_weight="1" to the ScrollView then it works for this case - the button is at the bottom and the ScrollView stops above it - but when the ScrollView doesn't have much content (replace the text with the one-liner) then the ScrollView doesn't shrink to fit around the content so is far too tall.
I've tried using RelativeLayout with no success - if the Button is android:layout_below the ScrollView then the ScrollView will push it off the bottom of the screen if it has a lot of content.
Here's what I want it to look like: in the first image the ScrollView has a lot of content and so expands to fill the available height but doesn't push the items below it (the button) offscreen, in the second image the ScrollView doesn't have much content so takes up just the height it needs allowing the items below it (the button) to move up the screen:

What you can do, is to correct the height in your code. It's a bit hacky and I would like to see another solution, but off the top of my head I do not know anything better.
What you would need is to add a OnGlobalLayoutListener and calculate within it the minimum of either the ScrollView height or the height of the container surrounding your ScrollView minus the height of your Button.
Then set the size with setLayoutParams() on your ScrollView.
And you have to remove the listener to avoid an endless loop :-)
final View scrollview = findViewById(R.id.scrollview);
final View container = findViewById(R.id.container);
final View button = findViewById(R.id.button);
scrollview.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
int height = scrollview.getHeight();
int heightButton = button.getHeight();
int heightContainer = container.getHeight();
int min = Math.min(heightContainer - heightButton, height);
int width = scrollview.getWidth();
Log.v("test", "min: " + min);
scrollview.setLayoutParams(new RelativeLayout.LayoutParams(width, min));
// do not forget to remove the listener
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
scrollview.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
else {
scrollview.getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
}
});
For this to work you have to use wrap_content as the height of the ScrollView in your layout file. And the outer container has to be a RelativeLayout so that the Buttonis rendered and has a non-zero height!
If you use paddings or margins you would have to consider those values in the computation.

Try this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/button"
android:background="#ff0000">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
<TextView
android:padding="5dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="taking\nup\lots\nof\nlines\nto\nmake\nthe\nscrollview"s\ncontent\ntaller\nthan\nthe\nspace\navailable\nto\nit\nwhich\nshould\nmake\nthe\nscrollview\nstop\nabove\nthe\nbutton\nand\nbecome\nscrollable" />
</LinearLayout>
</ScrollView>
<Button
android:id="#+id/button"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="Button" />
</RelativeLayout>

Just try adding fillViewport = "true" on your scroll view

focusing EditText on HorizontalScrollView causes ScrollView to hide EditText

I have a horizontal scroll view that takes up the right half of the screen. On it, I have an EditText. When I select the EditText to edit the text, the HorizontalScrollView scrolls to the right. I'm guessing it's trying to place the EditText to the leftmost position. Regardless, since the HorizontalScrollView takes up the rightside of the screen, by doing this, I can no longer see the EditText since its now covered up by the contents I put on the left side of the screen. How can I prevent HorizontalScrollView from automatically scrolling when I focus on something inside its layout?
Thanks. Much appreciated.
halp
Edit: Posting code. I'm actually creating my EditText's based off of generated info, so this is not what it actually looks like, but it should capture the ideai.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<View
android:layout_leftOf="#+id/Anchor"/>
<View
android:id="#+id/Anchor"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_centerHorizontal="true"
android:background="#000" />
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_rightOf="#+id/Anchor"
android:fillViewport="true" >
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true" >
<TableLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp" >
<TableRow>
<EditText>
ABOVE is the view that is going to the left
MOre views which would cause Scrolling to the right
</TableRow>
</TableLayout>
</HorizontalScrollView>
</ScrollView>
</RelativeLayout>

try this in XML the EditText if use
android:gravity="center"
remove it

Scroll text in a horizontal scroll view

I have seen a few posts similar to my issue. However, the solutions mentioned in those posts did not help me fix the problem. Here is the scenario. I have a TextView in a horizontal scroll view. The idea is as soon as a text (larger than the view) is appended to the TextView, it must be automatically scrolled to end. Here is the layout snippet.
<HorizontalScrollView
android:id="#+id/horizontalScrollView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
android:background="#color/subTitleColor"
android:fillViewport="true"
android:scrollbars="none" >
<TextView
android:id="#+id/drillPath"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="bottom"
android:text="this is a such a long text that scrolling is needed, scroll more"
android:textAppearance="?android:attr/textAppearanceSmall"
android:textColor="#color/textColorWhite" />
</HorizontalScrollView>
Upon an event, I do the following.
textView.append("do auto scroll");
Effectively, it should scroll the text to the end. But it isn't! What is it I am lacking?

First of all, your scrollview will never scroll since its content view (the TextView) is in fill_parent mode. it should wrap its content in order to leave space for the text and be bigger than its parent. (change your textView width to : android:layout_width="wrap_content" )
Then, there is nothing here to request the scroll, I don't think it should happen automatically.
Add something like this to request the scroll to the end of your scroll view :
textView.append("do auto scroll");
scrollView.post(new Runnable() {
#Override
public void run() {
scrollView.fullScroll(View.FOCUS_RIGHT);
}
});
Let me know when you've tried it.

Let try to fix your TextView height and change this width layoutParam to wrap_content
<HorizontalScrollView
android:id="#+id/horizontalScrollView1"
android:layout_width="match_parent" <-- Here
android:layout_height="10dp" <-- Here
android:layout_margin="5dp"
android:background="#color/subTitleColor"
android:fillViewport="true"
android:scrollbars="none" >
<TextView
android:id="#+id/drillPath"
android:layout_width="wrap_content" <-- Here
android:layout_height="10dp" <-- Here
android:gravity="bottom"
android:text="this is a such a long text that scrolling is needed, scroll more"
android:textAppearance="?android:attr/textAppearanceSmall"
android:textColor="#color/textColorWhite" />
</HorizontalScrollView>
Because of this layoutParam, Your text do not have enough size to scroll. It only have max width is screen width.
Hope that help.

Smooth scrolling Textview

I have a TextView, defined like this:
<TextView
android:id="#+id/play_info"
android:layout_width="0dip"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#color/play_info_background"
android:ellipsize="none"
android:maxLines="8"
android:orientation="vertical"
android:scrollbars="none"
android:singleLine="false"
android:textColor="#color/play_info_text_color"
android:textSize="#dimen/play_info_font_size"
android:overScrollMode="never" >
</TextView>
I set the TextView to be scrollable in code, like this:
cardInfo = (TextView) play.findViewById(R.id.play_info);
cardInfo.setMovementMethod(new ScrollingMovementMethod());
The TextView scrolls, but not smoothly, like anything inside a ScrollView.
I would like for it to scroll smoothly.
I have already tried putting the TextView (with scrolling disabled) inside a ScrollView, but this messes with the height of the TableRow it's contained in, and there doesn't seem to be a way to correct that.

The problem is if you want "smooth scroll" you have to place the TextView in a ScrollView. And when you do that, you can no longer
set the height of the TextView to "match_parent". Like, for example, when you need a large TextBox that is filled dynamically with text,
but not resized. And when you try by setting the ScrollView's attribute to "match_parent", the child TextView still wraps around the content.
I was able to do it like this:
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:drawable/edit_text">
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#null"
android:gravity="bottom"
android:singleLine="false"
android:typeface="serif"/>
</ScrollView>
</RelativeLayout>
A RelativeLayout container that serves as a new TextView, with the desired background, the original TextView with background set to null. So when the TextView
expands, with new text appended, it's just like text volume increasing. The text is aligned with the layout attributes if the ScrollView.
You may also need to disable scrolling for the TextView, to avoid collision with the ScrollView's scrolling in certain scenarios.

You probably missing focus attribute, Textview is not in focus so its not scrolling.
<TextView
android:id="#+id/title_itemcount"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:focusable="true"
android:focusableInTouchMode="true"
android:maxLines="3"
android:padding="4dp"
android:scrollbars="vertical"
android:textColor="#android:color/background_dark" />
Hope it helps... :)