Android - Relative Layout

Relative layout is a view group that displays child views in a relative positions. The position of each view can be specified relative to its siblings. 

The reference documentation on this can be found at at link below http://developer.android.com/guide/topics/ui/layout/relative.html 

There are many layout parameters available and they are mentioned in http://developer.android.com/reference/android/widget/RelativeLayout.LayoutParams.html 

Below is a sample which shows this. 

the tv_sample is made to the right of the tv_helloworld 

Note that we cannot specify a circular dependancy. for e.g. we cannot specify android:layout_toLeftOf="@+id/tv_sample" />, as that will become circular dependancy.

With the below XML, the screenshot from device was like this below 

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

    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

   

        android:layout_height="wrap_content"

        android:id="@+id/tv_username"

        android:layout_alignParentLeft="true"

        android:layout_alignParentStart="true" />

   

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/et_username"

        android:layout_alignParentRight="true"

        android:layout_alignParentTop="true"

        android:hint="Enter Username"/>

   

        android:layout_height="wrap_content"

        android:id="@+id/tv_password"

        android:layout_below="@+id/tv_username"

        android:paddingTop="25dp"

        android:layout_alignParentLeft="true" />

   

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/et_password"

        android:layout_alignParentRight="true"

        android:hint="Enter Password"

        android:layout_below="@+id/et_username"/>

   

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="Login"

        android:id="@+id/button"

        android:layout_below="@+id/et_password"

        android:layout_alignParentRight="true"/>

Screenshots: 

 

It is difficult to make any kind of complicated ui with relative layout as many developers say. 

I was trying to specify the layout widths with this layout, however, was unable to achieve so far. 

References: 

https://www.youtube.com/watch?v=xn9KYnwIoBE