Common attributes

Description

Each View and ViewGroup has a set of common attributes.

• layout_width specifies the width of the View or ViewGroup
• layout_height specifies the height of the View or ViewGroup
• layout_marginTop specifies extra space on the top side of the View or ViewGroup
• layout_marginBottom specifies extra space on the bottom side of the View or ViewGroup
• layout_marginLeft specifies extra space on the left side of the View or ViewGroup
• layout_marginRight specifies extra space on the right side of the View or ViewGroup
• layout_gravity specifies how child Views are positioned
• layout_weight specifies how much of the extra space in the layout should be allocated to the View
• layout_x specifies the x-coordinate of the View or ViewGroup
• layout_y specifies the y-coordinate of the View or ViewGroup

Note

The layout_weight and layout_gravity attributes are applicable only when a View is in either a LinearLayout or a TableLayout.

        
        <?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="vertical" >

            <TextView
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:text="@string/hello" />
        </LinearLayout>

For example, the width of the <TextView> element fills the entire width of its parent using the fill_parent constant.

Its height is indicated by the wrap_content constant, which means that its height is the height of its content (in this case, the text contained within it).

If you don't want the <TextView> view to occupy the entire row, you can set its layout_width attribute to wrap_content, like this:

<TextView
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="@string/hello" />

The preceding code will set the width of the view to be equal to the width of the text contained within it.