how to move 20dip margin left from center?

Question

i want to move a seekbar 20dip margin left from center.

android:progressDrawable="@drawable/progress_vertical"
            android:thumb="@drawable/seek_thumb" android:layout_height="80dip"
            android:layout_width="20dip" android:layout_marginBottom="50dip"
            android:layout_alignParentBottom="true" android:visibility="gone"
            android:layout_centerHorizontal="true" android:layout_marginLeft="20dip" /> 

but the above xml code shows it center only.

Answer 1

I made a workaround with a TextView in the middle that has no content (and is not visible).

<TextView
        android:id="@+id/viewMiddleInvisible"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/btnAtTheTop"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="30dp" />

<TextView
        android:id="@+id/tvAtLeft"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@id/viewMiddleInvisible"
        android:layout_marginRight="10dp"
        android:layout_toLeftOf="@id/viewMiddleInvisible"
        android:text="Some text" />

You would obviously have to replace tvAtLeft with whatever you want. Same principle if you want to have something to the right of the center.