Develop Reference

Add LinearLayout before ScrollView

I have a scrollview, but I want a linear layout with 3 buttons that stay on top when scrolling. So it should function kind of like navigation bar that sticks to the top.
Current code:
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.gridlayout.widget.GridLayout
android:id="#+id/gridRoot"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:columnCount="2"
app:rowCount="32">
</androidx.gridlayout.widget.GridLayout>
</ScrollView>

Place the ScrollView inside a vertical LinearLayout, and have those three buttons added above the ScrollView.
<LinearLayout android:orientation="vertical">
<YourButtonsHere/>
<ScrollView/>
</LinearLayout>

There are several ways to achieve this, but the easiest one is to have a vertical LinearLayout as the parent. You then put the buttons in a horizontal linearlayout, so that they are on the top and act as a 'bar'.
Then you only need to add the scrollview.
That way the user can scroll the scrollview and the 3 buttons stay on top of the scroll view.
<!-- vertical linear layout as parent -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<!-- Place buttons in a horizontal linearlayout, so that you have a bar on the
top-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<!-- buttons width=0 + same layout_weight, that way the width of the
linear layout is equally distributed between the 3 buttons-->
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"/>
<Button
android:layout_width="0dp"
android:layout_height=""
android:layout_weight="1"/>
<Button
android:layout_width="0dp"
android:layout_height=""
android:layout_weight="1"/>
</LinearLayout>
<!-- your scroll view here-->
<ScrollView
android:layout_width=""
android:layout_height="">
</ScrollView>
</LinearLayout>

XML:
<androidx.appcompat.widget.LinearLayoutCompat
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:weightSum="10">
<androidx.appcompat.widget.LinearLayoutCompat
android:layout_width="match_parent"
android:layout_height="0dp"
android:gravity="center"
android:layout_weight="1"
android:orientation="horizontal">
<com.sharedcode.widgets.CustomButton
style="#style/FlatButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="btn1"
android:layout_margin="#dimen/spacing_6" />
<com.sharedcode.widgets.CustomButton
style="#style/FlatButton"
android:layout_width="wrap_content"
android:text="btn2"
android:layout_height="wrap_content"
android:layout_margin="#dimen/spacing_6" />
<com.sharedcode.widgets.CustomButton
style="#style/FlatButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="btn3"
android:layout_margin="#dimen/spacing_6" />
</androidx.appcompat.widget.LinearLayoutCompat>
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="9"
tools:context=".MainActivity">
//in your case this is GridView
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/gridRoot"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:columnCount="2"
app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
app:rowCount="32"
app:spanCount="2"
tools:listitem="#layout/row_exam" />
</ScrollView>
</androidx.appcompat.widget.LinearLayoutCompat>

Layout does not align to center of the parent view

Im trying to align a circular image in the middle of two linearlayout with different colors, however the view for some reason does not align to the center
but stick to the left, below it I want to place a fragment. any help?
<?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" >
<FrameLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="3"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:background="#1b96d9"
android:orientation="vertical" >
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#e6e6e6"
android:orientation="vertical" >
</LinearLayout>
</LinearLayout>
<com.mikhaellopez.circularimageview.CircularImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="10dp"
android:gravity="center"
android:src="#drawable/doge"
app:border_color="#EEEEEE"
app:border_width="4dp"
app:shadow="true" />
</FrameLayout>
<LinearLayout
android:id="#+id/calendarCard1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="7"
android:background="#e6e6e6" />
</LinearLayout>

why not use a relative layout instead of so many nested Linear Layout. Using Relative layouts are easy and efficient. Check this http://www.mkyong.com/android/android-relativelayout-example/ for understanding the relative layouts

Your circular image layout is inside a FrameLayout along with the LinearLayout. FrameLayout basically puts all its children one atop another.

Using ScrollView with LinearLayout, Android

In my xml file , i have one linearLayout and a button. The linearLayout contains a lot of textViews and checkboxes. So i wanted these textViews and checkboxes to scroll but the button should remain at its place i.e it should not scroll with the textViews. For this purpose, i cover my linearLayout with scrollView like this
<?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"
android:background="#drawable/homeo11" >
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<LinearLayout
android:id="#+id/nexttodetail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginTop="10dp">
</LinearLayout>
</ScrollView>>
<Button android:id="#+id/Next4"
android:layout_gravity="right"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Next" />
</LinearLayout>
But doing this , hid my button. means the textviews and checkboxes are now scrolling properly but i can't see my next button. I try replacing the scrollView layout:height from fill_parent to wrap_content but this didn't work as well. Any help?

Use a RelativeLayout as your root View and then set your component with align_above, align_parent_top and align_parent_bottom like 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:background="#drawable/homeo11" >
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_above="#+id/Next4" >
<LinearLayout
android:id="#+id/nexttodetail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginTop="10dp">
(...)
</LinearLayout>
</ScrollView>>
<Button
android:id="#+id/Next4"
android:layout_gravity="right"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginTop="10dp"
android:text="Next" />
</RelativeLayout>

Android: How can you align a button at the bottom and listview above?

I want to have a button at the bottom of the listview.
If I use relativeLayout/FrameLayout, it aligns but listView goes down to very botton.
(Behind the button at the bottom)
FrameLayout:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
<FrameLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/btnButton"
android:text="Hello"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</FrameLayout>
</FrameLayout>
RelativeLayout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/btnButton"
android:text="Hello"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</RelativeLayout>
</RelativeLayout>
Above two codes only work like the first image. What I want is second image.
Can anybody help?
Thank you.

A FrameLayouts purpose is to overlay things on top of each other. This is not what you want.
In your RelativeLayout example you set the ListViews height and width to MATCH_PARENT this is going to make it take up the same amount of space as its parent, and thus take up all of the space on the page (and covers the button).
Try something like:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ListView
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0"/>
</LinearLayout>
The layout_weight dictates how the extra space is to be used. The Button does not want to stretch beyond the space it requires, so it has a weight of 0. The ListView wants to take up all of the extra space, so it has a weight of 1.
You could accomplish something similar using a RelativeLayout, but if it is just these two items then I think a LinearLayout is simpler.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#ffffff"
>
<ListView android:id="#+id/ListView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1">
</ListView>
<FrameLayout android:id="#+id/FrameLayout01"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<Button android:id="#+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"
android:layout_gravity="center_horizontal">
</Button>
</FrameLayout>
</LinearLayout>
Here is the design you are looking for.
Try it.

I needed two buttons side-by-side at the bottom. I used a horizontal linear layout, but assigning android:layout_height="0dp" and android:layout_weight="0" for the buttons' linear layout didn't work. Assigning android:layout_height="wrap_content" for just the buttons' linear layout did. Here's my working layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/new_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="New" />
<Button
android:id="#+id/suggest_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Suggest" />
</LinearLayout>
</LinearLayout>

RelativeLayout will ignore its children android:layout_width or android:layout_height attributes, if the children have attributes that properly define their left and right or top and bottom values, respectively.
To achieve the result on the right image, showing the list above the button, your layout should look like this:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#android:id/button1"
android:layout_alignParentTop="true"/>
<Button
android:id="#android:id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="#android:string/ok"/>
</RelativeLayout>
The key is to define android:layout_alignParentTop (defines top value) and android:layout_above (defines bottom value) in your RecyclerView. This way, RelativeLayout will ignore android:layout_height="match_parent", and the RecyclerView will be placed above the Button.
Also, make sure you look into android:layout_alignWithParentIfMissing, if you have a more complex layout and you still need to define these values.

I am using Xamarin Android, and my requirement is exactly the same as William T. Mallard, above, i.e. a ListView with 2 side-by-side buttons under it.
The solution is this answer didn't work in Xamarin Studio however - when I set the height of the ListView to "0dp", the ListView simply disappeared.
My working Xamarin Android code is as follows:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/ListView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_above="#+id/ButtonsLinearLayout" />
<LinearLayout
android:id="#id/ButtonsLinearLayout"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:orientation="horizontal"
android:layout_alignParentBottom="true">
<Button
android:id="#+id/Button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
<Button
android:id="#+id/Button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1" />
</LinearLayout>
</RelativeLayout>
I aligned ButtonsLinearLayout to the bottom of the screen, and set the ListView to be above ButtonsLinearLayout.

#jclova one more thing you can do is use layout-below=#+id/listviewid in relative layout

In your relative layout height of listview is match_parent which is fill_parent(for 2.1 and older) so best solution is if you want to use relative layout then first Declare your button then your list view, make list view position as above your button id, If you want button always at bottom then make it alignParentBottom..
Snippet is
<RelativeLayout
android:layout_width="fill_parent" android:layout_height="fill_parent"
android:id="#+id/rl1"><Button
android:layout_width="MATCH_PARENT"
android:layout_height="WRAP_CONTENT"
/><ListView
android:layout_width="MATCH_PARENT"
android:layout_height="0"
android:layout_above="#id/listview"/></RelativeLayout>
This prevents your list view taking whole place and make your button appear..

This will be the best and the most simple solution to the problem. Just add android:layout_above="#id/nameOfId" in the layout that you want to move above with respect to that layout.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.sumeru.commons.activity.CommonDocumentUploadActivity">
<ListView
android:id="#+id/documentList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="#id/verifyOtp" />
<com.sumeru.commons.helper.CustomButton
android:id="#+id/verifyOtp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="#string/otp_verification" />
</RelativeLayout>

How do I align views at the bottom of the screen?

Here's my layout code;
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:text="#string/welcome"
android:id="#+id/TextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</TextView>
<LinearLayout android:id="#+id/LinearLayout"
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="bottom">
<EditText android:id="#+id/EditText"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</EditText>
<Button android:text="#string/label_submit_button"
android:id="#+id/Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Button>
</LinearLayout>
</LinearLayout>
What this looks like is on the left and what I want it to look like is on the right.
The obvious answer is to set the TextView to fill_parent on height, but this causes no room to be left for the button or entry field.
Essentially the issue is that I want the submit button and the text entry to be a fixed height at the bottom and the text view to fill the rest of the space. Similarly, in the horizontal linear layout I want the submit button to wrap its content and for the text entry to fill the rest of the space.
If the first item in a linear layout is told to fill_parent it does exactly that, leaving no room for other items. How do I get an item which is first in a linear layout to fill all space apart from the minimum required by the rest of the items in the layout?
Relative layouts were indeed the answer:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:text="#string/welcome"
android:id="#+id/TextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true">
</TextView>
<RelativeLayout
android:id="#+id/InnerRelativeLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true" >
<Button
android:text="#string/label_submit_button"
android:id="#+id/Button"
android:layout_alignParentRight="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Button>
<EditText
android:id="#+id/EditText"
android:layout_width="fill_parent"
android:layout_toLeftOf="#id/Button"
android:layout_height="wrap_content">
</EditText>
</RelativeLayout>
</RelativeLayout>

The modern way to do this is to have a ConstraintLayout and constrain the bottom of the view to the bottom of the ConstraintLayout with app:layout_constraintBottom_toBottomOf="parent"
The example below creates a FloatingActionButton that will be aligned to the end and the bottom of the screen.
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_height="match_parent"
android:layout_width="match_parent">
<android.support.design.widget.FloatingActionButton
android:layout_height="wrap_content"
android:layout_width="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
</android.support.constraint.ConstraintLayout>
For reference, I will keep my old answer.
Before the introduction of ConstraintLayout the answer was a relative layout.
If you have a relative layout that fills the whole screen you should be able to use android:layout_alignParentBottom to move the button to the bottom of the screen.
If your views at the bottom are not shown in a relative layout then maybe the layout above it takes all the space. In this case you can put the view, that should be at the bottom, first in your layout file and position the rest of the layout above the views with android:layout_above. This enables the bottom view to take as much space as it needs, and the rest of the layout can fill all the rest of the screen.

In a ScrollView this doesn't work, as the RelativeLayout would then overlap whatever is in the ScrollView at the bottom of the page.
I fixed it using a dynamically stretching FrameLayout :
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:fillViewport="true">
<LinearLayout
android:id="#+id/LinearLayout01"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical">
<!-- content goes here -->
<!-- stretching frame layout, using layout_weight -->
<FrameLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
</FrameLayout>
<!-- content fixated to the bottom of the screen -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<!-- your bottom content -->
</LinearLayout>
</LinearLayout>
</ScrollView>

You can keep your initial linear layout by nesting the relative layout within the linear layout:
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:text="welcome"
android:id="#+id/TextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</TextView>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button android:text="submit"
android:id="#+id/Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true">
</Button>
<EditText android:id="#+id/EditText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_toLeftOf="#id/Button"
android:layout_alignParentBottom="true">
</EditText>
</RelativeLayout>
</LinearLayout>

The answer above (by Janusz) is quite correct, but I personnally don't feel 100% confortable with RelativeLayouts, so I prefer to introduce a 'filler', empty TextView, like this:
<!-- filler -->
<TextView android:layout_height="0dip"
android:layout_width="fill_parent"
android:layout_weight="1" />
before the element that should be at the bottom of the screen.

You can do this with a LinearLayout or a ScrollView, too. Sometimes it is easier to implement than a RelativeLayout. The only thing you need to do is to add the following view before the Views you want to align to the bottom of the screen:
<View
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_weight="1" />
This creates an empty view, filling the empty space and pushing the next views to the bottom of the screen.

1. Use ConstraintLayout in your root Layout
And set app:layout_constraintBottom_toBottomOf="parent" to let the Layout on the bottom of the screen:
<LinearLayout
android:id="#+id/LinearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintBottom_toBottomOf="parent">
</LinearLayout>
2. Use FrameLayout in your root Layout
Just set android:layout_gravity="bottom" in your layout
<LinearLayout
android:id="#+id/LinearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:orientation="horizontal">
</LinearLayout>
3. Use LinearLayout in your root Layout (android:orientation="vertical")
(1) Set a layout android:layout_weight="1" on the top of the your Layout
<TextView
android:id="#+id/TextView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:text="welcome" />
(2) Set the child LinearLayout for android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="bottom"
The main attribute is ndroid:gravity="bottom", let the child View on the bottom of Layout.
<LinearLayout
android:id="#+id/LinearLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="bottom"
android:orientation="horizontal">
</LinearLayout>
4. Use RelativeLayout in the root Layout
And set android:layout_alignParentBottom="true" to let the Layout on the bottom of the screen
<LinearLayout
android:id="#+id/LinearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:orientation="horizontal">
</LinearLayout>
Output

This also works.
<LinearLayout
android:id="#+id/linearLayout4"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_below="#+id/linearLayout3"
android:layout_centerHorizontal="true"
android:orientation="horizontal"
android:gravity="bottom"
android:layout_alignParentBottom="true"
android:layout_marginTop="20dp"
>
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
/>
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
/>
</LinearLayout>

Following up on Timores's elegant solution, I have found that the following creates a vertical fill in a vertical LinearLayout and a horizontal fill in a horizontal LinearLayout:
<Space
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />

You don't even need to nest the second relative layout inside the first one. Simply use the android:layout_alignParentBottom="true" in the Button and EditText.

If you don't wish to make many changes, then you could just put:
android:layout_weight="1"
for the TextView having ID as #+id/TextView i.e
<TextView android:text="#string/welcome"
android:id="#+id/TextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1">
</TextView>

Creating both header and footer, here is an example:
Layout XML
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/backgroundcolor"
tools:context=".MainActivity">
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="40dp"
android:background="#FF0000">
</RelativeLayout>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="40dp"
android:layout_alignParentBottom="true"
android:background="#FFFF00">
</RelativeLayout>
</RelativeLayout>
Screenshot

For a case like this, always use RelativeLayouts. A LinearLayout is not intended for such a usage.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/db1_root"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<!-- Place your layout here -->
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom"
android:orientation="horizontal"
android:paddingLeft="20dp"
android:paddingRight="20dp" >
<Button
android:id="#+id/setup_macroSavebtn"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Save" />
<Button
android:id="#+id/setup_macroCancelbtn"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Cancel" />
</LinearLayout>
</RelativeLayout>

Use the below code. Align the button to buttom. It's working.
<?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" >
<Button
android:id="#+id/btn_back"
android:layout_width="100dp"
android:layout_height="80dp"
android:text="Back" />
<TextView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="0.97"
android:gravity="center"
android:text="Payment Page" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Submit"/>
</LinearLayout>
</LinearLayout>

Use android:layout_alignParentBottom="true" in your <RelativeLayout>.
This will definitely help.

In case you have a hierarchy like this:
<ScrollView>
|-- <RelativeLayout>
|-- <LinearLayout>
First, apply android:fillViewport="true" to the ScrollView and then apply android:layout_alignParentBottom="true" to the LinearLayout.
This worked for me perfectly.
<ScrollView
android:layout_height="match_parent"
android:layout_width="match_parent"
android:scrollbars="none"
android:fillViewport="true">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:id="#+id/linearLayoutHorizontal"
android:layout_alignParentBottom="true">
</LinearLayout>
</RelativeLayout>
</ScrollView>

You can just give your top child view (the TextView #+id/TextView) an attribute:
android:layout_weight="1".
This will force all other elements below it to the bottom.

This can be done with a linear layout too.
Just provide Height = 0dp and weight = 1 to the layout above and the one you want in the bottom. Just write height = wrap content and no weight.
It provides wrap content for the layout (the one that contains your edit text and button) and then the one that has weight occupies the rest of the layout.
I discovered this by accident.

I used the solution Janusz posted, but I added padding to the last View since the top part of my layout was a ScrollView.
The ScrollView will be partly hidden as it grows with content. Using android:paddingBottom on the last View helps show all the content in the ScrollView.