Warning for android:supportsRtl in Androidmanifest

Question

I am developing android application with android:minSdkVersion="12" and android:targetSdkVersion="21" . In my manifest file i saw a warning:"The project references RTL attributes, but does not explicitly enable or disable RTL support with android:supportsRtl in the manifest".What is it actually means.I just gone through the link http://developer.android.com/guide/topics/manifest/application-element.html.But not get much idea about the problem. below is the code that i used in xml for one view.

<EditText
        android:id="@+id/terminal_id_edit_text"
        android:layout_width="fill_parent"
        android:layout_height="@dimen/edit_text_height"
        android:layout_marginEnd="@dimen/edit_text_right_margin"
        android:layout_marginLeft="@dimen/edit_text_left_margin"
        android:layout_marginRight="@dimen/edit_text_right_margin"
        android:layout_marginStart="@dimen/edit_text_left_margin"
        android:background="@drawable/editetxt_bg"
        android:inputType="text"
        android:hint="@string/terminal_id_text" 
        android:maxLength="8"
        android:nextFocusDown="@+id/client_id_edit_text"
        android:paddingLeft="@dimen/edit_text_padding"
        android:paddingRight="@dimen/edit_text_padding"
        android:singleLine="true"
        android:textColor="@color/color_white"
        android:textCursorDrawable="@null"
        android:textSize="@dimen/normal_text_size" />`

Answer 1

android:supportsRtl Declares whether your application is willing to support right-to-left (RTL) layouts. If set to true and targetSdkVersion is set to 17 or higher, various RTL APIs will be activated and used by the system so your app can display RTL layouts. If set to false or if targetSdkVersion is set to 16 or lower, the RTL APIs will be ignored or will have no effect and your app will behave the same regardless of the layout direction associated to the user's Locale choice (your layouts will always be left-to-right). The default value of this attribute is false. This attribute was added in API level 17.

for more : android:supportsRtl