Android text coloring based on background
<p>I'm currently working on an Android app that has a progress bar with textView at it's edge showing a date.</p>

<p>When the progress bar's background is grey, and it's fill is blue. I need to have the text color change according to the progress bar behind it - aka letters that have the progress bar's fill behind them should be grey, but letters that are above the empty parts of the progress bar should be blue.</p>

<p>How can I achieve this sort of thing?</p>

<p>Thanks in advance.</p>

<p>EDIT:
here's the xml of the progress bar and textView:</p>

<pre><code>&lt;ProgressBar 
        android:id="@+id/progressBar"
        android:layout_width="210dp"
        android:layout_height="12dp"
        android:layout_below="@id/contact"
        android:layout_toRightOf="@id/row_image"
        android:layout_marginTop="3dp"
        android:layout_marginLeft="20dp"
        style="@android:style/Widget.ProgressBar.Horizontal"
        android:progressDrawable="@drawable/s6_bar" /&gt;

&lt;TextView
        android:id="@+id/dateStart"
        android:layout_width="wrap_content"
        android:layout_height="12dp"
        android:textSize="10dp"
        android:textStyle="bold"
        android:textColor="#FF00FFFF"
        android:layout_below="@id/contact"
        android:layout_toRightOf="@id/row_image"
        android:layout_marginTop="1dp"
        android:layout_marginLeft="22dp" /&gt;
</code></pre>

<p>and I can't seem to post a picture because my rep is too low :(</p>
