Android Transparent TextView?

iTurki picture iTurki · Jul 7, 2011 · Viewed 122.1k times · Source

Simply, how to make a TextView transparent? (Not full transparency)

I searched the docs and the StackNetwork and couldn't find it? I guess there is something like this.

Thanks.

UPDATE

This is the XML code:

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:background="@drawable/background">

    <ImageView 
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:id="@+id/header"
    android:src="@drawable/logo1"
    />
    <ListView android:id="@android:id/list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="1"
    android:paddingRight="5dp"
    android:scrollbarStyle="outsideOverlay"
    android:cacheColorHint="#00000000" />


    <TextView
    android:id="@+id/footer"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="25sp"
    android:singleLine="true"
    android:background="#07000000"
    android:textColor="#FFFFFF"
    android:text="rrrrr" />

 </LinearLayout>

I want the footer TextView to be transparent so that the ListView items can be seen while scrolling

Answer

Marmoy picture Marmoy · Jul 7, 2011

See the Android Color resource documentation for reference.

Basically you have the option to set the transparency (opacity) and the color either directly in the layout or using resources references.

The hex value that you set it to is composed of 3 to 4 parts:

  • Alpha (opacity), i'll refer to that as aa

  • Red, i'll refer to it as rr

  • Green, i'll refer to it as gg

  • Blue, i'll refer to it as bb

Without an alpha (transparency) value:

android:background="#rrggbb"

or as resource:

<color name="my_color">#rrggbb</color>

With an alpha (transparency) value:

android:background="#aarrggbb"

or as resource:

<color name="my_color">#aarrggbb</color>

The alpha value for full transparency is 00 and the alpha value for no transparency is FF.

See full range of hex values below:

100% — FF
 95% — F2
 90% — E6
 85% — D9
 80% — CC
 75% — BF
 70% — B3
 65% — A6
 60% — 99
 55% — 8C
 50% — 80
 45% — 73
 40% — 66
 35% — 59
 30% — 4D
 25% — 40
 20% — 33
 15% — 26
 10% — 1A
  5% — 0D
  0% — 00

You can experiment with values in between those.