Linear Layout

How to create Linear Layout:

In a standard screen user interface (UI) layout, buttons are usually placed across the top of the

screen, or sometimes down the side of the screen, in a straight line. This is exactly what the

LinearLayout class does for you. It is designed to contain and automatically arrange UI elements

placed inside of it across the screen (using the horizontal orientation parameter) or up and down the

screen (using the vertical orientation parameter).

To set the LinearLayout object’s orientation, use the .setOrientation(integer)

method, with either the constant HORIZONTAL for horizontal or VERTICAL for vertical:

myLinearLayout.setOrientation(HORIZONTAL);

Here’s the attribute for orientation in the LinearLayout tag for XML:

android:orientation="vertical"

Thus, the entire LinearLayout opening tag for a Vertical UI layout looks like this:

<LinearLayout android:orientation="vertical">

so here’s how a Horizontal UI layout would normally be coded:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout width="match parent"

android:layout height="match parent"

android:orientation="horizontal">

<The Items To Be Arranged Horizontally Would Be Inside This Container>

</LinearLayout>

The first parameter of the LinearLayout XML tag is the path to the Android XML naming schema

definition (xmlns:android stands for: eXtensible Markup Language Naming Schema for Android).

The value for the layout width and height parameters, match parent, simply tells the LinearLayout

to expand to match its parent container size. Because this is the top level LinearLayout container,

the android:layout_width=“match_parent” would mean to fill the Android device (smartphone, tablet,

e-reader, or iTV) display screen width from one side to the other side. We already know what the

orientation does, so now we have our LinearLayout defined. Anything we place inside this container

will display horizontally across the screen, from left to right.

Create a android project and add following piece of code in activity_main.xml : 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:orientation="vertical"

android:layout width="match parent"

android:layout height="match parent" >

<TextView

android:layout width="wrap content"

android:layout height="wrap content"

android:text="@string/textareaone"

tools:context=".MainActivity" />

<TextView

android:layout width="wrap content"

android:layout height="wrap content"

android:text="@string/textareatwo"

tools:context=".MainActivity" />

</LinearLayout>

Go to string.xml,

<resources>

<string name="app name">LinearLayout Example</string>

<string name="textareaone">Text Area One!</string>

<string name="textareatwo">Text Area Two!</string>

<string name="menu settings">Settings</string>

<string name="title activity main">MainActivity</string>

</resources>

MainActivity.java :

public class MainActivity extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity main);

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

getMenuInflater().inflate(savedInstanceState);

setContentView(R.menu.activity main, menu);

return true;

}

}

Run the Application