Android RelativeLayout with Examples

In android, RelativeLayout is a ViewGroup which is used to specify the position of child View instances relative to each other (Child A to the left of Child B) or relative to the parent (Aligned to the top of parent).

 

Following is the pictorial representation of relative layout in android applications.

 

Android Relative Layout Example Diagram

 

In android, RelativeLayout is very useful to design user interface because by using relative layout we can eliminate the nested view groups and keep our layout hierarchy flat, which improves the performance of application.

Android Positioning Views in Relative Layout

As we discussed, in RelativeLayout we need to specify the position of child views relative to each other or relative to the parent. In case if we didn’t specify the position of child views, by default all child views are positioned to top-left of the layout.

 

Following are the some of most useful layout properties available to views in RelativeLayout.

 

AttributeDescription
layout_alignParentTop If it specified “true”, the top edge of view will match the top edge of the parent.
layout_alignParentBottom If it specified “true”, the bottom edge of view will match the bottom edge of parent.
layout_alignParentLeft If it specified “true”, the left edge of view will match the left edge of parent.
layout_alignParentRight If it specified “true”, the right edge of view will match the right edge of the parent.
layout_centerInParent If it specified “true”, the view will be aligned to the centre of parent.
layout_centerHorizontal If it specified “true”, the view will be horizontally centre aligned within its parent.
layout_centerVertical If it specified “true”, the view will be vertically centre aligned within its parent.
layout_above It accepts another sibling view id and places the view above the specified view id.
layout_below It accepts another sibling view id and places the view below the specified view id.
layout_toLeftOf It accepts another sibling view id and places the view left of the specified view id.
layout_toRightOf It accepts another sibling view id and places the view right of the specified view id.
layout_toStartOf It accepts another sibling view id and places the view to start of the specified view id.
layout_toEndOf It accepts another sibling view id and places the view to the end of the specified view id.

Android RelativeLayout Example

Following is the example of creating a RelativeLayout with different controls in android application.

 

Create a new android application using android studio and give names as RelativeLayout. In case if you are not aware of creating an app in android studio check this article Android Hello World App.

 

Now open an activity_main.xml file from \res\layout path and write the code like as shown below

activity_main.xml

<?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"
   
android:paddingLeft="10dp"
   
android:paddingRight="10dp">
    <
Button
       
android:id="@+id/btn1"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_alignParentLeft="true"
       
android:text="Button1" />
    <
Button
       
android:id="@+id/btn2"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_alignParentRight="true"
       
android:layout_centerVertical="true"
       
android:text="Button2" />
    <
Button
       
android:id="@+id/btn3"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_alignParentLeft="true"
       
android:layout_centerVertical="true"
       
android:text="Button3" />

    <
Button
       
android:id="@+id/btn4"
       
android:layout_width="match_parent"
       
android:layout_height="wrap_content"
       
android:layout_alignParentBottom="true"
       
android:text="Button4" />
    <
Button
       
android:id="@+id/btn5"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_alignBottom="@+id/btn2"
       
android:layout_centerHorizontal="true"
       
android:text="Button5" />
    <
Button
       
android:id="@+id/btn6"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_above="@+id/btn4"
       
android:layout_centerHorizontal="true"
       
android:text="Button6" />
    <
Button
       
android:id="@+id/btn7"
       
android:layout_width="wrap_content"
       
android:layout_height="wrap_content"
       
android:layout_toEndOf="@+id/btn1"
       
android:layout_toRightOf="@+id/btn1"
       
android:layout_alignParentRight="true"
       
android:text="Button7" />
</
RelativeLayout>

Once we are done with creation of layout, we need to load the XML layout resource from our activity onCreate() callback method, for that open main activity file MainActivity.java from \java\com.tutlane.relativelayout path and write the code like as shown below.

MainActivity.java

package com.tutlane.linearlayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {
   
@Override
   
protected void onCreate(Bundle savedInstanceState) {
       
super.onCreate(savedInstanceState);
        setContentView(R.layout.
activity_main);
    }
}

If you observe above code we are calling our layout using setContentView method in the form of R.layout.layout_file_name. Here our xml file name is activity_main.xml so we used file name activity_main.

 

Generally, during the launch of our activity, onCreate() callback method will be called by the android framework to get the required layout for an activity.

Output of Android RelativeLayout Example

When we run above example using the android virtual device (AVD) we will get a result like as shown below.

 

Android Relative Layout Example Result

 

This is how we can use RelativeLayout in android applications based on our requirements.