title: (Android)How can I show a part of image?
body: <p>I have an image like this-></p>
  
  <p><img src="https://i.stack.imgur.com/k2Tki.jpg" alt="enter image description here"></p>
  
  <p>And I want to show like this-></p>
  
  <p><img src="https://i.stack.imgur.com/QzFoW.jpg" alt="enter image description here"></p>
  
  <p>Then I can choose how much I can see(0~1,0=can not see,1=Whole picture,0.5=half picture,....etc,read from user input)</p>
  
  <p>How to do that?</p>
  
  <p>I tried to use <code>android:scaleType</code> but it is not working.</p>