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LinearLayout not expanding inside a ScrollView

I have a LinearLayout inside a ScrollView that has android:layout_height="fill_parent", but it doesn't expand to the full height of the ScrollView. My layout looks something like:

level    layout    layout_width    layout_height
1    LinearLayout    fill_parent    fill_parent
2    LinearLayout    fill_parent    wrap_content
3    (some irrelevant stuff)
2    ScrollView      fill_parent    fill_parent <-- this expands full height
3    LinearLayout    fill_parent    fill_parent <-- this does not (has orientation=vertical)
(following stuff probably are irrelevant, but just to be sure:)
4    TextView        fill_parent    fill_parent
4    LinearLayout    fill_parent    wrap_content

I can see that the LinearLayout doesn't expand the full height of the ScrollView because in Eclipse in Android Layout Editor, if I select the ScrollView (in the Outline panel) it is highlighted with a red border that fills the screen to the bottom but when I select the LinearLayout its highlight doesn't expand to the bottom of the screen. How can I get it to do so?

The effect I'm trying to achieve is to have some text and a button below it (inside the LinearLayout in level 4 there's just a button). The text can be big enough to need a scrollbar, in which case I want the user to have to scroll down in order to see the button. In case the text is not big enough for a scroll bar, I want the LinearLayout containing the button to stick to the bottom of the screen.

At first I thought I shouldn't post the full XML because it's usually a turn-down to see a huge chunk of code in a question. However, it seems it might be necessary, so here's the full layout.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:id="@+id/video_layout"
        android:focusable="true"
        style="@style/VideoLayout">
        <FrameLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:foreground="@android:drawable/ic_media_play"
            android:foregroundGravity="center">
            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/video_thumb"
                android:padding="5dip"
                android:background="#454545"/>
        </FrameLayout>
        <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:focusable="true"
            style="@style/VideoTitle"
            android:id="@+id/video_title"
            android:layout_gravity="center"
            android:layout_weight="1"/>
    </LinearLayout>
    <ScrollView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1">
        <!-- this ScrollView expands the full height of the screen.
             However, the next LinearLayout does not expand the full height of the ScrollView -->
        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_weight="1"
            android:layout_gravity="fill"
            android:orientation="vertical"
            android:id="@+id/info_layout">
            <TextView
                android:layout_width="fill_parent"
                android:layout_height="fill_parent"
                android:id="@+id/info_body"
                style="@style/InfoText"/>
            <LinearLayout
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal"
                style="@android:style/ButtonBar">
                    <Button
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_gravity="center"
                        android:layout_weight="1"
                        android:text="@string/button_readmore"
                        android:id="@+id/btn_read_more"/>
            </LinearLayout>
        </LinearLayout>
    </ScrollView>
</LinearLayout>

At the moment I have r开发者_如何学Cesorted to android:layout_gravity="bottom" on the problematic LinearLayout, which makes the button stick to the bottom of the screen no matter what. But that also makes the text stick to the bottom of the screen, which is not exactly what I was after.

Update: scratch that, android:layout_gravity="bottom" makes the ScrollView unable to, well, scroll. Other ideas?


Found the solution myself in the end. The problem was not with the LinearLayout, but with the ScrollView (seems weird, considering the fact that the ScrollView was expanding, while the LinearLayout wasn't).

The solution was to use android:fillViewport="true" on the ScrollView.


I know this post is very old, For those who don't want to use android:fillViewport="true" because it sometimes doesn't bring up the edittext above keyboard. Use Relative layout instead of LinearLayout it solves the purpose.


Can you provide your layout xml? Doing so would allow people to recreate the issue with minimal effort.

You might have to set

android:layout_weight="1"

for the item that you want expanded


The solution is to use

android:fillViewport="true"

on Scroll view and moreover try to use

"wrap_content" instead of "fill_parent" as "fill_parent"

is deprecated now.


I have dynamically used to get this . I have a LinearLayout and within this used ScrollView as a child. Then i take again LinearLayout and add what ever View u want to this LinearLayout and then this LinearLayout add to ScrollView and finally add this ScrollView to LinearLayout. Then u can get scroll in ur ScrollView and nothing will left to visible.

LinearLayout(Parent)--ScrollView(child of LinerLayout) -- LinearLayout(child of ScrollView)-- add here textView, Buttons , spinner etc whatever u want . Then add this LinearLyout to ScrollView. Bcoz only one CHILD for ScrollView applicable and last add this ScrollView to LinearLyout.If defined area is exceed from Screen size then u will get a Scroll within ScrollView.


In my case i haven't given the

orientation of LinearLayout(ScrollView's Child)

So by default it takes horizontal, but scrollview scrols vertically, so please check if 'android:orientation="vertical"' is set to your ScrollView's Child(In the case of LinearLayout).

This was my case hopes it helps somebody

.


All the answers here didn't work (completely) for me. Just to recap what we wanna do for a complete answer: We have a ScrollView, supposedly filling the device's viewport, thus we set fillViewport to "true" in the layout xml. Then, inside the ScrollView, we have a LinearLayout containing everything else, and that LinearLayout should be at least as high as its parent ScrollView, so stuff that's supposed to be on the bottom (of the LinearLayout) is actually, as we want it, at the bottom of the screen (or at the bottom of the ScrollView, in case the LinearLayout's content has more hight than the screen.

Example activity_main.xml layout:

<ScrollView
    android:id="@+id/layout_scrollwrapper"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:fillViewport="true"
    android:layout_alignParentTop="true"
    android:layout_above="@+id/layout_footer"
    >
<LinearLayout
    android:id="@+id/layout_scrollwrapper_inner"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    >
...content which might or might not be higher than screen height...
</LinearLayout>
</ScrollView>

Then, in the activity's onCreate, we "wait" for the LinearLayout's layouting to be done (implying it's parent's layouting is also already done) and then set it's minimum height to the ScrollView's height. Thus it also works in case the ScrollView does not occupy the whole screen height. Whether you call .post(...) on the ScrollView or the inner LinearLayout should not make that much of a difference, if one doesn't work for you, try the other.

public class MainActivity extends AppCompatActivity {

@Override // Activity
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    LinearLayout linearLayoutWrapper = findViewById(R.id.layout_scrollwrapper_inner);

    ...

    linearLayoutWrapper.post(() -> {
        linearLayoutWrapper.setMinimumHeight(((ScrollView)linearLayoutWrapper.getParent()).getHeight());
    });
}
...
}

Sadly, it's not an xml-only solution, but it works well enough for me, hope it also helps some other tortured android dev scouring the interwebs in search for a solution to this problem ;D

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