Android Scrollview Layout Problem

Android: ScrollView Issue

Your EditText should have a height of wrap_content. fill_parent has no meaning in a ScrollView. If you want the EditText to fill your ScrollView when it's content is smaller than the ScrollView, use android:fillViewport="true" on the ScrollView.

Android ScrollView layout problem

I'm interested in that topic too, so I did a bit of research. First: Never put a ListView in a ScrollView (as you found out yourself). Unfortunately googling this problem doesn't lead to any solutions, so I tried my suggestion from my comment above.

I implemented a custom ListAdapter and put the ListViews into one parent ListView. This doesn't work (leads to the same problem as with a ScrollView). Speaking to the guys on the official android-irc #android-dev on freenode, they told me that putting ListViews into a ListView is as bad as or even worse than putting them into a ScrollView. Unfortunately they also couldn't help me with the problem.

There seems to be only one way to achieve what you want to do; see the answer on this similar question Scrolling with Multiple ListViews for Android . The idea is to merge all ListViews into a single one by a custom adapter and to insert some kind of headers between entries. This is absolutely doable but might require some special effort.

Android Scrollview layout issue

You can use android:descendantFocusability attribute to control that descendants of ScrollView should get focus or not. If you want that the ScrollView should not scroll down automatically then set the value of android:descendantFocusability attribute to blocksDescendants and add this attribute to the LinearLayout which is the child of ScrollView.

<LinearLayout 
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="top"
    android:orientation="vertical"
    android:descendantFocusability="blocksDescendants" >

XML Layout weight not working in a ScrollView on android API23

One should understand how dimensions are calculated.
Let's look one by one.

1) ScrollView is fill_parent/fill_parent (actually one can change this to match_parent/match_parent as fill_parent is deprecated as far as I remember, but it doesn't matter in this case).
So, ScrollView is shown fits whole screen (width and height).

2) LinearLayout inside ScrollView is match_parent/wrap_content. And that is correct. One should use wrap_content for views that inside ScrollView.
The reason why - is that ScrollView is used to wrap long views with usually unknown height (like lists). Imagine here match_parent as height - height of LinearLayout would be calculated based on height of scroll view, which is whole screen height, and LinearLayout height can be greater that screen height. Just not logical. But everything is OK till now. Move on.

3) Items inside LinearLayout. You want them to be 1/10 and 9/10 of height of parent layout. Also, you set height for inner items to 0 to show that you want height to be calculated from weights.
And here you got a cycle of dependencies. LinearLayout height is wrap_content and depends on sum of heights of inner elements.
And inner elements' height is calculated from parent LinearLayout height.

Additionally, you want ImageView to be 1/10 of the LinearLayout height. But actually seems like you want ImageView to be 1/10 of the screen's height, as LinearLayout height can be greater than screen's height (and looks like this is what you get on your device).

You say, that everything is OK in preview in Android Studio.
To demonstrate that not everything is OK try this:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:fillViewport="true"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">
        <ImageView
            android:layout_weight="1"
            android:adjustViewBounds="true"
            android:layout_height="0dp"
            android:layout_gravity="center"
            android:layout_width="wrap_content"
            android:id="@+id/image"
            android:scaleType="fitCenter"
            android:src="@drawable/bjj2" />
        <LinearLayout
            android:layout_weight="10"
            android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="0dp">
            <View
                android:layout_width="match_parent"
                android:layout_height="1000dp"/>

        </LinearLayout>
    </LinearLayout>

</ScrollView>

Just put some big (bigger than screen's height) view inside your inner-inner LinearLayout and you will see that in preview your image is bigger than 1/10 of screen's height. But it is 1/10 of LinearLayout's height.

How to solve your issue?
I think the only way is to calculate 1/10 of the screen's height and resize bitmap with image you want to have and set that bitmap to ImageView.
Or any other way to set exact height to ImageView.

Or review your layout and create something different.

ScrollView not scrolling at all

Answer: the ScrollView is not working when used as the root element of an XML layout. It has to be wrapped inside a LinearLayout.

Solution then :

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

    <ScrollView android:id="@+id/scroll_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fillViewport="true" >

        <LinearLayout android:id="@+id/scroll_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" >

        </LinearLayout>
    </ScrollView>
</LinearLayout>

ScrollView not sizing itself correctly

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.

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