title: Image's border in libgdx
body: <p>Since I'm pretty new in Libgdx development, I would like to ask if it is possible to make image borders (to mark it up as selected) using it?  I've read that one solution is to make 2 separate images: one with border and one without. However pretty all of my images are the same size and there are many of them so don't know if it's the best idea. Are there any other options?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>So i have chosen 2nd idea ( 1x1 image ) but there is some problem with it. First of all i can't make that borderImage to be under clicked element. Another problem is size of borderImage ( it's not same ). When i click in the center of button its smaller ( about couple pixels ) than when i click on the edge. Do u know what can cause these problems and how to fix them? 
  Code : </p>
  
  <pre><code>public void create(){
          stage = new Stage();
          Gdx.input.setInputProcessor(stage);
  
          skin = new Skin(Gdx.files.internal("data/uiskin.json"));
  
          Texture borderTexture = new Texture(Gdx.files.internal("data/select.png") );
          final Image borderImage = new Image( borderTexture );
  
          TextButton exitButton = new TextButton("Exit",skin);
  
          exitButton.addListener(new ClickListener(){
              public void clicked(InputEvent event, float x, float y)
                  {
                    borderImage.setSize( event.getTarget().getWidth() + 1 * 2, event.getTarget().getHeight() + 1 * 2);
  
  
  
  
                  Vector2 loc = new Vector2(0, 0);
                 Vector2 stageLoc = event.getTarget().localToStageCoordinates(loc); 
                 borderImage.setPosition( stageLoc.x, stageLoc.y);  
  
                 System.out.println("" + event.getTarget().getWidth() + " " +event.getTarget().getHeight() + " " + event.getTarget().getX() + 
                         " " + event.getTarget().getY() + " " + stageLoc.x + " " + stageLoc.y);
  
                 stage.addActor(borderImage);
                  }       
              }
          );
  
          Table table = new Table();
  
          table.add(exitButton).colspan(3);
  
          table.setFillParent(true);
          stage.addActor(table);
  }
  </code></pre>
  
  <p>And the output i have : 
  29.0 25.0 4.0 1.0 466.0 257.0 // clicked in the center of button
  37.0 27.0 462.0 256.0 462.0 256.0 // clicked on the edge of button</p>