Develop Reference

buttons disappearing from a linear layout

I have a complicated linear layout, with some buttons and edittext:
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="top|center_horizontal"
android:orientation="vertical"
android:weightSum="1"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="400dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="40dp"
android:layout_marginTop="0dp"
android:text="#string/stop"
android:textSize="18dp"
android:textStyle="bold" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<EditText
android:id="#+id/text"
android:hint="#string/hint"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/choose"
android:layout_alignParentLeft="true"
android:minWidth="150dp"
android:textSize="10sp"/>
<Button
android:id="#+id/text2"
android:hint="#string/favourites"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/choose"
android:layout_alignParentRight="true"
android:layout_toRightOf="#+id/text"
android:textSize="10sp"
/>
<Button
android:id="#+id/text3"
android:hint="#string/clean"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/choose"
android:layout_alignParentRight="true"
android:layout_toRightOf="#+id/text"
android:textSize="10sp"
/>
</LinearLayout>
<Button
android:id="#+id/button"
android:text="#string/request"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/text2"
android:onClick="lookUp"
android:textSize="12sp"
/>
<ScrollView
android:id="#+id/scrollView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#3d455b"
android:layout_alignParentLeft="true"
android:layout_below="#+id/button">
<HorizontalScrollView
android:id="#+id/hscrll1"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<RelativeLayout
android:id="#+id/RelativeLayout1"
android:layout_width="fill_parent"
android:layout_gravity="left"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TableLayout
android:id="#+id/table_main"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_centerHorizontal="false"
android:stretchColumns="2">
</TableLayout>
</RelativeLayout>
</HorizontalScrollView>
</ScrollView>
</LinearLayout>
Everything looks at it should on a large screen (tablet): I have the first line with the edittext and two buttons, on the line below I have the other button, and below it I have the scrollview (with the table).
When I switch to normal screen (smartphone), only the first line is appearing, the rest not being visible.
What could the solution be?

In Small Screen device there are problem with margin you set, try to
remove android:layout_marginBottom="400dp" from your ParentLayout and manage your Layout according them

At the second linear_layout (that have horizontal orientation) all of your views, have match parent width that cause non of them are visible. I think it's what you want:
`
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<EditText
android:id="#+id/text"
android:hint="#string/hint"
android:layout_width="0dp"
android:layout_weight = "1"
android:layout_height="wrap_content"
android:minWidth="150dp"
android:textSize="10sp"/>
<Button
android:id="#+id/text2"
android:hint="#string/favourites"
android:layout_width="0dp"
androidlayout_weight = "1"
android:layout_height="wrap_content"
android:textSize="10sp"
/>
<Button
android:id="#+id/text3"
android:hint="#string/clean"
android:layout_width="0dp"
android:layout_weight = "1"
android:layout_height="wrap_content"
android:textSize="10sp"
/>
</LinearLayout>
`

LinearLayout put child at the right side

I m trying to have a textview and a button in linear layout with horizontal orientation. The textview should appear at the starting and the button should appear at the end. I thought giving gravity right to the button would do the trick but the buttons doesn't move to the right side. I m thinking if I should probably use relative layout?
<\LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Buy Now" />
<\/LinearLayout>

My way (using a RelativeLayout):
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="Buy Now"
/>
</RelativeLayout>
See how I explicitly align the TextView to the Parent's left side and the Button to the Parent's right side
You can then center the TextView vertically in the RelativeLayout, by setting:
android:layout_centerVertical="true"
in the TextView itself
Newr OS versions may prefer this:
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:text="Buy Now"
/>
</RelativeLayout>

Try below xml:
<?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="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Buy Now" />
</LinearLayout>

There is a cleaner way to do this, using LinearLayout : just give the left element a width of 0 and a weight of 1, and set the right one's width on wrap_content. And that's it!
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Buy Now" />
</LinearLayout>

There are two approach:
1) You can use RelativeLayout in which you can drag your Button where you want..
2) You can use weight property for LinearLayout.
<?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="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="0dp"
android:layout_weight="0.8"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:text="Rs 3579.0"
/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="0dp"
android:layout_weight="0.2"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Buy Now" />
</LinearLayout>

Use this layout instead..
<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="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Rs 3579.0"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Buy Now"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>

use android:layout_gravity="end" to your linear layout to move all the elements to the right

Another simple solution here that doesn't rely on using a RelativeLayout is having an empty view between both elements using layout_weight to make sure it fills the empty space.
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Rs 3579.0"/>
<view
android:layout_height="0dp"
android:layout_width="0dp"
android:layout_weight="1" />
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Buy Now" />
</LinearLayout>
That way you can achieve what you want by only using a LinearLayout, now, I am not sure if this is more efficient than using a RelativeLayout. But for me it always feels a bit like an overkill to go for a relative in such a simple layout.

Just add empty view with 0dp width and 1 weight
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#+id/productPriceTextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Rs 3579.0"
/>
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="1"/>
<Button
android:id="#+id/buyNowButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Buy Now" />
</LinearLayout>

Put a button to the right and middle of a layout

If I have a layout in xml as follow
<RelativeLayout
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_toLeftOf="#+id/bFb"
android:orientation="vertical" >
<EditText
android:id="#+id/etUserName"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<EditText
android:id="#+id/etPass"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPassword"
/>
<Button
android:id="#+id/bLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login" />
</LinearLayout>
<Button //This is the button on question
android:id="#+id/bFb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/linearLayout1"
android:text="Button" />
//there are more stuffs here below the linear layout
</RelativeLayout>
How can I have the button to the right of the linearlayout AND aligned at the middle of linear layout? I don't want the button borders to stretch the whole linear layout, just the middle of the linear layout
Thank you

You can achieve what you want by changing RelativeLayout to LinearLayout and supply a weight for its first child like that
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content"
android:orientation="vertical" >
<EditText
android:id="#+id/etUserName"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText
android:id="#+id/etPass"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPassword" />
<Button
android:id="#+id/bLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login" />
</LinearLayout>
<Button
android:id="#+id/bFb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="Button" />
</LinearLayout>
Which will produce this
EDIT
You can achieve it with relative layout that way
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:orientation="vertical" >
<EditText
android:id="#+id/etUserName"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText
android:id="#+id/etPass"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPassword" />
<Button
android:id="#+id/bLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login" />
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayout2"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal"
android:layout_toRightOf="#id/linearLayout1" >
<Button
android:id="#+id/bFb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="Button" />
</LinearLayout>
</RelativeLayout>
But it needs some tweeks to produce the exact same thing, in my opinion LinearLayout's weight serve better in your case, so if I were in your shoe I choose the LinearLayout solution and wrap it in a RelativeLayout

basic android scroll bars not visible

<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" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Choose Details"
android:id="#+id/textView"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Year"
android:id="#+id/textView2"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Branch"
android:id="#+id/textView3"
android:layout_below="#+id/textView2"
android:layout_alignParentLeft="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Semester"
android:id="#+id/textView4"
android:layout_below="#+id/textView3"
android:layout_alignParentLeft="true"/>
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/scrollView"
android:layout_alignTop="#+id/textView2"
android:layout_alignParentRight="true"/>
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/scrollView2"
android:layout_alignTop="#+id/textView4"
android:layout_alignParentRight="true"/>
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/scrollView3"
android:layout_below="#+id/textView4"
android:layout_alignRight="#+id/scrollView2"/>
</RelativeLayout>
I am bit new to android.Could anyone tel me that why arent the three scroll bars visible along the text views.I want to display the scrolls adjacent to their respective textviews.Moreover is the relative layout the best way to align the widgets .

Until and unless, you add View element in ScrollView, the ScrollViews which u have added cannot be visible, but they are present in layout. ScrollView must contain a single View item either it is a LinearLayout, RelativeLayout with child views such as TextView, ImageView, EditText, Button as below:
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/scrollView2"
android:layout_alignTop="#+id/textView4"
android:layout_alignParentRight="true">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<ImageView
android:id="#+id/image1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp" />
</LinearLayout>
</ScrollView>
or a View element as a single child for ScrollView as below:
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/scrollView2"
android:layout_alignTop="#+id/textView4"
android:layout_alignParentRight="true">
<ImageView
android:id="#+id/image1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"/>
</LinearLayout>
</ScrollView>

A scroll view is not a scroll bar.
It must contain some elements.
Example :
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_below="#+id/imageView1" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Button" />
<Button
android:id="#+id/button2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Button" />
<Button
android:id="#+id/button3"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Button" />
</LinearLayout>
</ScrollView>
Your code should be
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Choose Details"
android:id="#+id/textView"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Year"
android:id="#+id/textView2"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Branch"
android:id="#+id/textView3"
android:layout_below="#+id/textView2"
android:layout_alignParentLeft="true"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Semester"
android:id="#+id/textView4"
android:layout_below="#+id/textView3"
android:layout_alignParentLeft="true"/>
<ScrollView/>

The ScrollView in your layout is not visible because your it does not contain any widget with height and width. If you want to see your ScrollView then you have to set some value to the width and height (for example android:layout_width="40dip") properties, and a backgroundColor(), after this you will able to see you ScrollView.

1) Use LinearLayout instead of RelativeLayout, set android:orientation="vertical"
2) Put the textview inside your scrollview, like this:
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
...
</TextView>
</ScrollView>
If you put all textviews inside a single scrollview, you will have one scrollbar(Note however that scrollview can only contain one child view, so you'll need to wrap those textviews under a linear layout); if you put one text view in each scrollview and stack those scrollviews vertically in linear layout, then you'll have separate scrollbar for each textview.

How to tell Android relative layout to take all space left betwean two elements. Does not matter how much is that space

How to tell Android relative layout to take all space left between two elements. Does not matter how much is that space.
<?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"
android:orientation="vertical">
<TableLayout android:layout_below="#id/title_container"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id = "#+id/usb_config_title">
<TableRow android:layout_gravity="center_horizontal">
<TextView android:layout_width="398dp"
android:layout_height="4px"
android:text=" "/>
<TextView android:layout_width="4px"
android:layout_height="4px"
android:text=" "
android:background="#color/title_background"/>
<TextView android:layout_width="398dp"
android:layout_height="4px"
android:text=" "/>
</TableRow>
<TableRow android:layout_gravity="center_horizontal">
<TextView android:text="#string/usb_stick"
android:layout_width="398dp"
android:gravity="center"
android:layout_height="wrap_content"
android:textSize="22dp"/>
<TextView android:layout_width="4px"
android:layout_height="fill_parent"
android:text=" "
android:background="#color/title_background"/>
<TextView android:text = "#string/usb_internal_memory"
android:layout_width="398dp"
android:gravity="center"
android:layout_height="wrap_content"
android:textSize="22dp"/>
</TableRow>
<TableRow android:layout_gravity="center_horizontal">
<TextView android:layout_width="398dp"
android:layout_height="5px"
android:text=" "/>
<TextView android:layout_width="4px"
android:layout_height="5px"
android:text=" "
android:background="#color/title_background"/>
<TextView android:layout_width="398dp"
android:layout_height="5px"
android:text=" "/>
</TableRow>
</TableLayout>
<LinearLayout android:orientation="horizontal"
android:layout_below="#id/usb_config_title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<ListView
android:id="#+id/list3"
android:layout_width="398px"
android:layout_height="wrap_content"
android:drawSelectorOnTop="false"
android:scrollbarAlwaysDrawVerticalTrack="true"
/>
<TextView android:layout_width="4px"
android:layout_height="fill_parent"
android:text=" "
android:background="#color/title_background"/>
<ListView
android:id="#+id/list4"
android:layout_width="398px"
android:layout_height="wrap_content"
android:drawSelectorOnTop="false"
android:scrollbarAlwaysDrawVerticalTrack="true"
/>
</LinearLayout>
<include layout="#layout/buttons_bottom_with_relative"/>
</RelativeLayout>
So i need id/list3 to last till button bar which is. At the moment id/list3 is covered by button bar.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:gravity="bottom"
android:layout_weight="1"
android:id="#+id/controls"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:baselineAligned="false"
style="#android:style/ButtonBar"
android:background="#drawable/bottom_layout_selector"
>
<Button
android:layout_width="100px"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/startButton"
android:text="#string/start"
android:visibility="invisible"
/>
<Button
android:layout_width="100px"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/stopButton"
android:text="#string/stop"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/nextButton"
android:text="#string/next"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/resetStatistics"
android:text="#string/reset_statistics"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/histogramSettings"
android:text="#string/histogram_settings"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/saveButton"
android:text="#string/save"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/loadConfig"
android:text="#string/load_config"
android:visibility="invisible"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:id="#+id/saveConfig"
android:text="#string/save_config"
android:visibility="invisible"
/>
</LinearLayout>

Have you tried adding this to the linear layout that includes list3
android:layout_below="#id/usb_config_title"
android:layout_above="#id/controls"
So the linear layout positions itself between those two.
I don't think you can use the weight attribute for Relative layouts. If you align one layout to the top of the screen and one to the bottom then tell the one in the middle to above and below the other two it should fill in the space

What you probably need is to set the layout_weight property of the Relative Layout, and the whole thing to be within a LinearLayout. If you could show us the XML you have so far we can see for sure!