Linear Layout and weight in Android

Question

I always read about this funny weight value in the Android documentations. Now I want to try it for the first time but it isn\'t working at all.

As I understand it

Answer 1

This image summarizes the Linear layout.

You can follow this link for more information on the topic. Just Maths - Views, View Groups and Layouts

Video Tutorial For Linear Layout : Width, Height & Weights

Android Linear Layout Tutorial

Answer 2

Perhaps setting both of the buttons layout_width properties to "fill_parent" will do the trick.

I just tested this code and it works in the emulator:

<LinearLayout android:layout_width="fill_parent"
          android:layout_height="wrap_content">

    <Button android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="hello world"/>

    <Button android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="goodbye world"/>

</LinearLayout>

Be sure to set layout_width to "fill_parent" on both buttons.

Answer 3

Substitute wrap_content with fill_parent.

Answer 4

In the width field of button, replace wrap-content with 0dp.
Use layout_weight attribute of a view.

android:layout_width="0dp"  

This is how your code will look like:

<LinearLayout
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:orientation="horizontal">

 <Button
    android:text="Register"
    android:id="@+id/register"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:padding="10dip"
    android:layout_weight="1" />

 <Button
    android:text="Not this time"
    android:id="@+id/cancel"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:padding="10dip"
    android:layout_weight="1" />    

</LinearLayout>

layout_weight is used to distribute the whatever left space into proportions. In this case, the two buttons are taking "0dp" width. So, the remaining space will be divided into 1:1 proportion among them, i.e. the space will be divided equally between the Button Views.

Answer 5

 <LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">

    <Button
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="2"
        android:text="Button 1" />

    <Button
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="3"
        android:text="Button 2" />

    <Button
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="2"
        android:text="Button 3" />

    </LinearLayout>

Answer 6

Below are the changes (Marked in BOLD) in your code:

<LinearLayout
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:orientation="horizontal">

     <Button
        android:text="Register"
        android:id="@+id/register"
        android:layout_width="0dp" //changes made here
        android:layout_height="wrap_content"
        android:padding="10dip"
        android:layout_weight="1" /> //changes made here

     <Button
        android:text="Not this time"
        android:id="@+id/cancel"
        android:layout_width="0dp" //changes made here
        android:layout_height="wrap_content"
        android:padding="10dip"
        android:layout_weight="1" /> //changes made here

  </LinearLayout>

Since your LinearLayout has orientation as horizontal, therefore you will need to keep your width only as 0dp. for using weights in that direction . (If your orientation was vertical, you would have kept your height only 0dp).

Since there are 2 views and you have placed android:layout_weight="1" for both the views, it means it will divide the two views equally in horizontal direction (or by width).