How to right align widget in horizontal linear layout Android?

This is the code I am using and it is not working:

<?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="horizontal">

    <TextView android:text="TextView" android:id="@+id/textView1"
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content"
        android:gravity="right">
    </TextView>

</LinearLayout>

Try to add empty View inside horizontal LinearLayout before element that you want to see right, e.g.:

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

    <View
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_weight="1" />                

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

Do not change the gravity of the LinearLayout to "right" if you don't want everything to be to the right.

Try:

1. Change TextView's width to fill_parent
2. Change TextView's gravity to right

Code:

    <TextView 
              android:text="TextView" 
              android:id="@+id/textView1"
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"   
              android:gravity="right">
    </TextView>

As a supplement to alcsan's answer, you can use Space since API 14 (Android 4.0 ICE_CREAM_SANDWICH), document here.

Space is a lightweight View subclass that may be used to create gaps between components in general purpose layouts.

<?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="horizontal" >

    <Space
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <TextView
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content"
        android:text="TextView"
        android:gravity="right" />

</LinearLayout>

For apps that supporting API levels under 14, there is an android.support.v4.widget.Space since Android Support Library r22.1.0.

With Linear Layout

<LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/select_car_book_tabbar"
        android:gravity="right" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:src="@drawable/my_booking_icon" />
    </LinearLayout>

with FrameLayout

<FrameLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/select_car_book_tabbar">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical|right"
            android:src="@drawable/my_booking_icon" />
    </FrameLayout>

with RelativeLayout

<RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/select_car_book_tabbar">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_centerInParent="true"
            android:src="@drawable/my_booking_icon" />
    </RelativeLayout>