I know we can set the following values to the android:gravity
and android:layout_gravity
properties:
center
center_vertical
center_horizontal
, etc.But I am confused regarding both of these.
What is the difference between the usage of android:gravity
and android:layout_gravity
?
gravity
arranges the content inside the view. layout_gravity
arranges the view's position outside of itself.Sometimes it helps to see a picture, too. The green and blue are TextViews
and the other two background colors are LinearLayouts
.
layout_gravity
does not work for views in a RelativeLayout
. Use it for views in a LinearLayout
or FrameLayout
. See my supplemental answer for more details.gravity
won't have any effect. Thus, wrap_content
and gravity
are meaningless together.layout_gravity
won't have any effect. Thus, match_parent
and layout_gravity
are meaningless together.layout_gravity=center
looks the same as layout_gravity=center_horizontal
here because they are in a vertical linear layout. You can't center vertically in this case, so layout_gravity=center
only centers horizontally.gravity
and layout_gravity
on the views within a layout. To see what happens when you set the gravity
of the of the parent layout itself, check out the supplemental answer that I referred to above. (Summary: gravity
doesn't work well on a RelativeLayout
but can be useful with a LinearLayout
.)So remember, layout_gravity arranges a view in its layout. Gravity arranges the content inside the view.
Here is the xml for the above image for your reference:
<?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="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#e3e2ad"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textSize="24sp"
android:text="gravity=" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:background="#bcf5b1"
android:gravity="left"
android:text="left" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:background="#aacaff"
android:gravity="center_horizontal"
android:text="center_horizontal" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:background="#bcf5b1"
android:gravity="right"
android:text="right" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:background="#aacaff"
android:gravity="center"
android:text="center" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#d6c6cd"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textSize="24sp"
android:text="layout_gravity=" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:layout_gravity="left"
android:background="#bcf5b1"
android:text="left" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:layout_gravity="center_horizontal"
android:background="#aacaff"
android:text="center_horizontal" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:layout_gravity="right"
android:background="#bcf5b1"
android:text="right" />
<TextView
android:layout_width="200dp"
android:layout_height="40dp"
android:layout_gravity="center"
android:background="#aacaff"
android:text="center" />
</LinearLayout>
</LinearLayout>