How to align LinearLayout at the center of its parent? - android-layout

I've looked through numerous similar questions here at SO, but nothing helps.
I have a hierarchy of different nested layouts, all have android:layout_width="fill_parent", and the inner-most layout has android:layout_width="wrap_content - I need to align it at the center (horizontally). How do I do that?
Update:: I've found the cause of the problem - if I put the inner LinearLayout into RelativeLayout with android:layout_width="fill_parent", it still wraps it's content. The TableRow, however, is really filling the screen.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TableLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TableRow >
<LinearLayout
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="1"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="2"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</TableRow>
</TableLayout>
</FrameLayout>
</LinearLayout>

These two attributes are commonly confused:
android:gravity sets the gravity of the content of the View it's
used on.
android:layout_gravity sets the gravity of the View or
Layout relative to its parent.
So either put android:gravity="center" on the parent or android:layout_gravity="center" on the LinearLayout itself.
I have caught myself a number of times mixing them up and wondering why things weren't centering properly...

Please try this in your linear layout
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"

<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<LinearLayout
android:orientation="horizontal"
android:layout_centerHorizontal="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="1"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="2"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</RelativeLayout>
consider wrapping relativeLayout over LinearLayout. android:layout_centerHorizontal="true" will position the view center horizontal.

add layout_gravity="center" or "center_horizontal" to the parent layout.
On a side note, your LinearLayout inside your TableRow seems un-necessary, as a TableRow is already an horizontal LinearLayout.

If your parent is a LinearLayout, you can add to it :
android:orientation="vertical"
android:gravity="center"
And to it's child
android:gravity="center"
It should at least center horizontally !

This worked for me.. adding empty view ..
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:orientation="horizontal"
>
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="1"
/>
<com.google.android.gms.ads.AdView
android:id="#+id/adView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
ads:adSize="BANNER"
ads:adUnitId="#string/banner_ad_unit_id" >
</com.google.android.gms.ads.AdView>
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="1"
/>
</LinearLayout>

Try this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
>
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TableLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TableRow >
<LinearLayout
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:layout_gravity="center_horizontal" >
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="1"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="2"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</TableRow>
</TableLayout>
</FrameLayout>
</LinearLayout>

this worked for me.
<LinearLayout>
.
.
.
android:gravity="center"
.
.>
<TextView
android:layout_gravity = "center"
/>
<Button
android:layout_gravity="center"
/>
</LinearLayout>
so you're designing the Linear Layout to place all its contents(TextView and Button) in its center and then the TextView and Button are placed relative to the center of the Linear Layout

Try <TableRow android:gravity="center_horizontal"> This will center the inner LinearLayout within the tablerow.

I have faced the same situation while designing custom notification. I have tried with the following attribute set with true.
android:layout_centerInParent.

#jksschneider explation is almost right. Make sure that you haven't set any gravity to parent layout, and then set layout_gravity="center" to your view or layout.

I experienced this while working with nested RelativeLayouts. My solution ended up being simple, but it's a little gotcha that's worth being aware of.
My layout was defined with...
android:layout_height="fill_parent"
android:layout_below="#id/someLayout
android:gravity="center"
...however, I didn't think that the layout below this one was placed on top of it. Everything inside this layout was shifted towards the bottom instead of centered. Adding...
android:layout_above="#id/bottomLayout"
...fixed my issue.

Try this:
android:layout_gravity="center_horizontal"

for ImageView or others views who layout-gravity or gravity does not exist use :
android:layout_centerInParent="true" in the child
(I had a relative layout with an ImageView as a child).

The problem is that the root's (the main layout you store the other elements) gravity is not set. If you change it to center the other elements' gravity must work just fine.

Below is code to put your Linearlayout at bottom and put its content at center. You have to use RelativeLayout to set Layout at bottom.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:background="#97611F"
android:gravity="center_horizontal"
android:layout_alignParentBottom="true"
android:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="50dp"
android:text="View Saved Searches"
android:textSize="15dp"
android:textColor="#fff"
android:gravity="center_vertical"
android:visibility="visible" />
<TextView
android:layout_width="30dp"
android:layout_height="24dp"
android:text="12"
android:textSize="12dp"
android:textColor="#fff"
android:gravity="center_horizontal"
android:padding="1dp"
android:visibility="visible" />
</LinearLayout>
</RelativeLayout>

Related

Linear Layout and children not visible

Hi sorry I am having difficulty in getting my layout to been seen when I run the application
I don't see anything when I run my application
here is my XML code
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="409dp"
android:layout_height="729dp"
android:layout_marginStart="1dp"
android:layout_marginLeft="1dp"
android:layout_marginTop="1dp"
android:layout_marginEnd="1dp"
android:layout_marginRight="1dp"
android:layout_marginBottom="1dp"
android:orientation="vertical"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/edtName"
android:layout_width="match_parent"
android:layout_height="44dp"
android:text="Name" />
<ScrollView
android:id="#+id/scrlText"
android:layout_width="match_parent"
android:fillViewport="true"
android:isScrollContainer="true"
android:layout_height="638dp">
<LinearLayout
android:id="#+id/lltext"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" />
</ScrollView>
<LinearLayout
android:id="#+id/hllsend"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<EditText
android:id="#+id/edtInput"
android:layout_width="159dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:ems="10"
android:inputType="textPersonName" />
<Button
android:id="#+id/btnSend"
android:layout_width="10dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Button" />
</LinearLayout>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
How do I make my items visible when running the application?
In your simple layout code, there are many problems. For example:
1.
android:layout_width="409dp"
android:layout_height="729dp"
such android screen size is hard to get. And in Android layout principal, you'd better use relative layout rather than such hard code size. Here you can replace it with match_parent or wrap_content.
In the same way.
android:layout_height="638dp"
totally over screen height ,make no space for hllsend to show.
I suggest you learn some android layout principal before write android app.
It's not a good practice to add LinearLayout in ConstraintLayout and I think it's the issue with your code you just need to make you LinearLayout as a parent and remove your ConstraintLayout.
NOTE: please do necessary adjustment.
Please check quick example for your code I didn't run this.
<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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="409dp"
android:layout_height="729dp"
android:layout_marginStart="1dp"
android:layout_marginLeft="1dp"
android:layout_marginTop="1dp"
android:layout_marginEnd="1dp"
android:layout_marginRight="1dp"
android:layout_marginBottom="1dp"
android:orientation="vertical"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/edtName"
android:layout_width="match_parent"
android:layout_height="44dp"
android:text="Name" />
<ScrollView
android:id="#+id/scrlText"
android:layout_width="match_parent"
android:fillViewport="true"
android:isScrollContainer="true"
android:layout_height="638dp">
<LinearLayout
android:id="#+id/lltext"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" />
</ScrollView>
<LinearLayout
android:id="#+id/hllsend"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<EditText
android:id="#+id/edtInput"
android:layout_width="159dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:ems="10"
android:inputType="textPersonName" />
<Button
android:id="#+id/btnSend"
android:layout_width="10dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Button" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
put all your xml codes in LinearLayout and remove ConstraintLayout . thats may helps.

Setting up two LinearLayouts aligning one at the buttom and the other centered on the rest of the screen

I am very new to android designing and have some basic problems setting up a
simple layout:
Here are my goals:
I would like to have two buttons at the end of the Screen, each having the same size, filling the width of the screen.
A second LinearLayout should fill the rest of the screen, but all its content should be vertically centred.
I tried my best, but sometimes my bottom LinearLayout completely disappears, sometimes the bottom one looks fine, but the other layouts content isn't centred. I just don't know what to try out anymore. Here is what I got so far:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableName"
android:hint="#string/TableNameHint" />
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableDescripion"
android:hint="#string/TableDescriptionHint" />
<EditText
android:inputType="textPassword"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:hint="#string/TablePasswordHint"
android:id="#+id/TablePassword"
android:fontFamily="sans-serif" />
</LinearLayout>
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom">
<Button
android:id="#+id/BtnAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnAddTable" />
<Button
android:id="#+id/BtnCancelAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnCancelAddTable"
/>
</LinearLayout>
</LinearLayout>
I tried my best, but sometimes my bottom LinearLayout completely disappears, sometimes the bottom one looks fine, but the other layouts content isn't centred.
Your button is sometimes disappearing because your top sub Linearlayout's height is match_parent, which makes it fill the parent's height and cover the below views.
What you need is a layout structure like below:
Description:
So like the description in the picture, you can set weightsum to your parent layout and set the weight percentage to your sub layout. And wrap your button's Linearlayout using Relativelayout, so that you can get the buttons centered.
Codes:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="4">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:layout_gravity="center">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableName"
android:hint="#string/TableNameHint" />
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableDescripion"
android:hint="#string/TableDescriptionHint" />
<EditText
android:inputType="textPassword"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:hint="#string/TablePasswordHint"
android:id="#+id/TablePassword"
android:fontFamily="sans-serif" />
</LinearLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="3">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_gravity="bottom">
<Button
android:id="#+id/BtnAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnAddTable" />
<Button
android:id="#+id/BtnCancelAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnCancelAddTable" />
</LinearLayout>
</RelativeLayout>
</LinearLayout>
Update:
RelativeLayout has restrictions, it can only contain one child. So if you want to add more widgets in the bottom region then the best option for you is to use ConstraintLayout.
For Xamarin, you can follow the below steps:
Open Android SDK Manager in your VS:
Tools->Other->Check below versions of Constraintlayout and solver for Android like below and apply changes:
Install Xamrin.Android.Support.Constraint.Layout to your project through nuget package:
Then use the following xml codes:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:id="#+id/editText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Name" />
<EditText
android:id="#+id/editText2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Name"
app:layout_constraintTop_toBottomOf="#+id/editText" />
<EditText
android:id="#+id/editText3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="#+id/editText2" />
<android.support.constraint.Guideline
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/guideline"
app:layout_constraintGuide_percent="0.6"
android:orientation="horizontal"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="#id/guideline"
android:orientation="horizontal">
<Button
android:id="#+id/button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Button"/>
<Button
android:id="#+id/button2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Button"/>
</LinearLayout>
</android.support.constraint.ConstraintLayout>
Short Explaination:
use android.support.constraint.Guideline with app:layout_constraintGuide_percent="0.6" to draw an invisible line to help position the buttons.(guideline will be 60% from the top screen). Then let buttons' stacklayout to be bottom of the guideline.
For detail usage of ConstraintLayout, please refer to Build responsive UI with ConstraintLayout.
Well, what you are trying to do is more achievable by just adding a Relative layout to the mix:
What you have to do is this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="6"
android:layout_gravity="center">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableName"
android:hint="#string/TableNameHint" />
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/editTableDescripion"
android:hint="#string/TableDescriptionHint" />
<EditText
android:inputType="textPassword"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:hint="#string/TablePasswordHint"
android:id="#+id/TablePassword"
android:fontFamily="sans-serif" />
</LinearLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<Button
android:id="#+id/BtnAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnAddTable" />
<Button
android:id="#+id/BtnCancelAddTable"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="#string/BtnCancelAddTable"
/>
</LinearLayout>
</RelativeLayout>
</LinearLayout>
RelativeLayout:
The Official Android developer website says :
RelativeLayout is a view group that displays child views in relative positions. The position of each view can be specified as relative to sibling elements (such as to the left of or below another view) or in positions relative to the parent RelativeLayout area (such as aligned to the bottom, left or centre).

How to overlap in Relative Layout Android Studio

I'm trying to send the white image in the back of my button and text in Relative Layout. Here is the code:
<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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.example.sahni.lightspeed.starting_screen"
tools:showIn="#layout/activity_starting_screen"
android:background="#drawable/q1">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/title"
android:textSize="70sp"
android:id="#+id/title"
android:textColor="#00e1ff"
android:layout_centerHorizontal="true"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/start_button"
android:id="#+id/button"
android:textSize="20sp"
android:layout_centerInParent="true"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:onClick="buttonOnClick"/>
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/imageView"
android:layout_alignLeft="#+id/title"
android:layout_alignStart="#+id/title"
android:layout_below="#+id/title"
android:background="#ffffff" />
</RelativeLayout>
The layout sets for the image aren't correct, but I don't know which ones to use to get the output I want. A screenshot of current output:
Am I using the best layout for this problem ?
Can someone please explain to me how the solution works too?
Just move to first ImageView in your RelativeLayout :
<RelativeLayout ... >
<ImageView ... />
<TextView ... />
<Button ... />
</RelativeLayout>
Your ImageView has android:layout_below="#+id/title" property so it' always below your title, so it can't be in background of your title.

Android ScrollView Not Scrolling Correctly

I've been making my way through thenewboston's android tutorials and I'm stuck on number 35. There is supposed to be a scroll bar that takes up a weight of 30 at the top of the app. There are 6 textview/edittext field groups in the code, but I deleted 5 for simplicity. My problem is that all of the text and text boxes appear on the page and are not confined to the given weight (they all just show up on the page). Has anyone else had this problem or know how to fix it?
Please, I'm new to stackoverflow. If you think this is a stupid question, please explain to me why and how I can ask it better.
Here is what it looks like: http://imgur.com/gJmOgqk
<?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="vertical"
android:weightSum="100" >
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="30" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />
<EditText
android:id="#+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10" >
</EditText>
</LinearLayout>
</ScrollView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="40"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="30"
android:orientation="vertical" >
<AnalogClock
android:id="#+id/analogClock1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>
Welcome to StackOverflow!
Couple of things,
TheNewBoston made a mistake. Whenever you use weights you need
to set the height (or width) of that element to 0dp. I've changed
that in your code.
You shouldn't rely on the xml tool that eclipse has, you should always try to launch your app to some type of a device (emulator or preferably hardware)
I think by ScrollBar, you mean ScrollView? Because you're not doing anything to control the appearance of the scroll bar right now.
The parent of your layout (in this case) should match_parent, not wrap. (this is your main issue)
Also, you don't really need weightSum, android will just sum all the weights anyway.
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="30" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />
<EditText
android:id="#+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10" >
</EditText>
</LinearLayout>
</ScrollView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="40"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="30"
android:orientation="vertical" >
<AnalogClock
android:id="#+id/analogClock1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
You need to set the height of the views to 0dp if you are using weight. match_parent is causing problems. Also set the height of root view to match_parent. Try this, if I add many EditText's to the LinearLayout in the ScrollView it seems to give the effect you are after:
<?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:weightSum="100">
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="40">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"/>
<EditText
android:id="#+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10">
</EditText>
</LinearLayout>
</ScrollView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="30"
android:orientation="vertical">
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="30"
android:orientation="vertical">
<AnalogClock
android:id="#+id/analogClock1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
</LinearLayout>

Admob to Listview: Android Layout

Once more I need some help. Trial and error is not working so well. Can someone please look at my code? I want my listview to contain admob ads at the top of the page and I am struggling a bit this morning. Thanks in advance!
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="5dp"
>
<com.google.ads.AdView
android:id="#+id/adView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
ads:adSize="BANNER"
ads:adUnitId="xxxxxxxxxxxxxxx"
ads:loadAdOnCreate="true"
android:layout_alignParentTop="true" />
<TextView
android:id="#+id/txtPlaceName"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:ellipsize="end"
android:singleLine="true"
android:text="saa"
android:textSize="25sp"
android:layout_below="#id/adView" />
<LinearLayout
android:id="#+id/layout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageView
android:id="#+id/imgType"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/marker1" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="#+id/txtCityState"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="city, st"
android:textSize="15sp" />
<TextView
android:id="#+id/txtDistance"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:textSize="15sp" />
</RelativeLayout>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<RatingBar
android:id="#+id/average_ratingbar"
style="?android:attr/ratingBarStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:numStars="5"
android:stepSize="1.0" />
<TextView
android:id="#+id/txtCommentsCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:textSize="15sp" />
</RelativeLayout>
</LinearLayout>
</LinearLayout>
</LinearLayout>
Short answer
The Banner ad needs 320dp width. Your base LinearLayout has android:padding="5dp" so you only have 310dp left, and the ad therefore doesn't fit on the screen.
For the future
Android has a logging tool called LogCat that keeps track of all messages that are logged. AdMob SDK provides logging messages that can be very helpful when debugging these issues. This is how I was able to solve your problem.
You can view the LogCat output using the command line by following the directions from the link provided above, or you can view the LogCat output in Eclipse by going to Window -> Show View -> LogCat. When requesting an ad, the SDK logged the following message:
Not enough space to show the ad! Wants: <320,50>, Has: <310,473>
From there it was pretty easy to tell that you didn't have the full 320 width, and sure enough your top level layout had 5dp padding on each side.
Unrelated Layout Tip
Fyi, the android:layout_alignParentTop and android:layout_below attributes only do anything inside of a RelativeLayout. In the layout you provided above, these attributes on the AdView and the TextView don't do anything.

Resources