Develop Reference

Android Layouts: Stick one Layout to the top of the screen and place another Layout centred below

I am working on my first android-project, a memory-game in Android Studio. The gameActivity-Frame should contain some textViews, displayed in one line (for stats) on the top of the screen and the memory-cards below. There are mutliple memory-versions, so the number of memory-cards vary - and by that the dimension of thier GridLayout.
My main Layout is a LinearLayout (vertical). I placed another LinearLayout (horizontal) on it, where the Textviews take place. To display the cards, I used a GridLayout which will be filled with cards once the game started.
The LinearLayout (with textViews) should always stick on the top of the screen. The GridLayout should be centered in the remaining space below.
What I get is that both Layouts either stick in the middle, or that the LinearLayout is correct, but the GridLayout is either on the bottom or on the top of the remaining space.
I tried to find a solution here on SO, and I think I tried every possible combination of the gravity- and layout_gravity - settings of the components. I can imagine the problem is that I can use either wrap_content or match_parent in the main Layout, but not both. Guess I'd need wrap_content to stick the first Layout to the top and match_parent to use the whole space below this Layout.
How can I stick the first Layout to the top and center the GridLayout in the remaining space?
The picture shows my current layout (see code below) and how I want it to look.
center_GridLayout
Edit to clarify:
The LinearLayout should stick to the top of the screen, the GridLayout should be
centered in the remaining space below the LinearLayout.
RelativeLayout won't do the job properly, because the layouts might overlap, depending on the amount of memory-cards and the user's device's dimensions.
I uploaded another screenshot where it's better visible what I want to achieve:
This is my .xml (deleted some unimportant textViews):
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:id="#+id/MemoryLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="20dp"
android:layout_marginTop="10dp"
android:layout_marginRight="20dp"
android:layout_marginBottom="10dp"
android:layout_weight="1"
android:orientation="horizontal">
<TextView
android:id="#+id/textStatsPairs"
android:layout_width="65dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/textStatsPairs" />
</LinearLayout>
<GridLayout
android:id="#+id/gridLayoutMainActivityTEST"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:columnCount="4"
android:foregroundGravity="center"
android:orientation="horizontal"
android:rowCount="4"
android:textAlignment="center"
android:useDefaultMargins="true"
tools:context=".GameActivity" />
</LinearLayout>

use relative layout or constraint 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:id="#+id/MemoryLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<LinearLayout
android:layout_alignParentTop="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="20dp"
android:layout_marginTop="10dp"
android:layout_marginRight="20dp"
android:layout_marginBottom="10dp"
android:layout_weight="1"
android:orientation="horizontal">
<TextView
android:id="#+id/textStatsPairs"
android:layout_width="65dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/textStatsPairs" />
</LinearLayout>
<GridLayout
android:layout_centerInParent="true"
android:id="#+id/gridLayoutMainActivityTEST"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:columnCount="4"
android:foregroundGravity="center"
android:orientation="horizontal"
android:rowCount="4"
android:textAlignment="center"
android:useDefaultMargins="true"
tools:context=".GameActivity" />
</RelativeLayout >

You can use relative layout along with linearlayout.From your question i got that you want your linearlayout always stick to top and GridLayout always stick to center.If this is the case then i think following code snippet will help you.
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<GridLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true">
</GridLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_alignParentTop="true">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Texts Here"
android:layout_gravity="center"
android:gravity="center"/>
</LinearLayout>
</RelativeLayout>

The ConstraintLayout was what fixed my problem... Here's the solution that finally works perfectly:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:id="#+id/memory_activity_4x4"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="#+id/linearLayout_4x4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_gravity="center"
android:layout_marginLeft="20dp"
android:layout_marginTop="10dp"
android:layout_marginRight="20dp"
android:layout_marginBottom="10dp"
android:layout_weight="1"
android:orientation="horizontal">
<TextView
android:id="#+id/textStatsPairs"
android:layout_width="65dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/textStatsPairs" />
</LinearLayout>
<GridLayout
android:id="#+id/gridLayout4x4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:columnCount="4"
android:foregroundGravity="center"
android:orientation="horizontal"
android:rowCount="4"
android:textAlignment="center"
android:useDefaultMargins="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/linearLayout_4x4"
tools:context=".GameActivity" />
</androidx.constraintlayout.widget.ConstraintLayout>

Defining a specific xml layout with a nested layout

I am in the process of designing my first Android application and I am trying to get the hang of creating an XML layout. (I have a great deal of experience with Java)
Essentially what I wanna do:
Where the outlines describes:
Blue: A basic View (where i can set a text)
Red: A ButtonView (Used so the user can synchronize data)
Green: A nested RelativeLayout (Where i am going to add a lot of other stuff)
More specifically what i wanna do:
So my question is this: How can i set up the different layouts? I am having the must trouble with setting up the blue and red views because i want the red view to fill up around 25% of the screen width(and the blue to fill up the last 75%).
Thank you in advance.

Use layout_weight property to specify the percentage of screen space a view takes.
Like here, for e.g:
<LinearLayout android:layout_height="match_parent" android:layout_width="match_parent"
android:orientation="vertical" .........>
<LinearLayout android:layout_height="wrap_content" android:layout_width="match_parent"
android:orientation="horizontal">
<EditText android:layout_height="wrap_content" android:layout_width="0dip"
android:layout_weight="3"/>
<Button android:layout_height="wrap_content" android:layout_width="0dip"
android:layout_weight="1"/>
</LinearLayout>
//Other view
</LinearLayout>

Use following xml, this is specially designed for you.
<?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" >
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_weight="0.75">
<TextView
android:id="#+id/headingTextView"
style="#android:style/TextAppearance.WindowTitle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Cafe Vigeos"
android:textColor="#android:color/white"
android:textSize="30sp" />
</RelativeLayout>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_weight="0.25">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</RelativeLayout>
<RelativeLayout
android:id="#+id/nested_relative_layout"
android:layout_width="match_parent"
android:layout_height="fill_parent" >
</RelativeLayout>
</LinearLayout>

Android ScrollView and buttons at bottom of the screen

I want to implement this: A ScrollView that contains many elements (ImageViews, TextViews, EditTexts etc) and then after the ScrollView some buttons (which are custom ImageViews) that appear always exactly at the bottom of the screen.
If I use the android:fillViewport="true" attribute, then if the elements of the ScrollView are too big to fit in the screen size the buttons get invisible . If I use the android:Weight=1 attribute then the ScrollView gets only 50% of the Screen when the screen is big and it can fit (I want the buttons to take a small percentage, about 10%). If I set the android:Weight to bigger values then the buttons appear very small.
Please help! Maybe it is something simple that I overlooked but I’ve been banging my head for hours!

Just created and tested it. Looks like you want.
<?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">
<LinearLayout
android:id="#+id/buttons"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:gravity="center"
android:layout_alignParentBottom="true">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Custom Button1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Custom Button2"/>
</LinearLayout>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#id/buttons">
<!--Scrollable content here-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="test text"
android:textSize="40dp"/>
</LinearLayout>
</ScrollView>
</RelativeLayout>

<?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="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hallo Welt"
/>
</LinearLayout>
</ScrollView>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Go next page"
android:layout_alignParentRight="true" />
</RelativeLayout>
</LinearLayout>

This worked for me. Give the scroll view a weight of 1. Put all the other widgets following the scroll view in a layout. The scroll view will grow enough to not block the rest.
Widgets in scroll view and rest at bottom

scrollview cannot fit the screen because you put it on a linear layout, so linear layout fit in the screen,
just try to make scrollview as root elemen on xml layout
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<!-- Here you can put some XML stuff and BOOM! your screen fit to scrollview -->
</LinearLayout>
</ScrollView>

If you do not want to use RelativeLayout, it is better to use LinearLayout. This method is better in my opinion.
Just set the layout_weight to one

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.