title: android:set gray scale filter to imageView
body: <p>i use this <a href="https://code.google.com/p/svg-android/" rel="noreferrer">library</a> to show svg image on imageView , i want to show locked and unlocked mode with this imageView, when state is locked show imageView in grayscale color filter. 
  something like this code on css :</p>
  
  <p><code>-webkit-filter: grayscale(100%);
  opacity: 0.5;</code></p>
  
  <p>how can i do this ? can anybody help me ?
  thanks</p>