title: Handler not fetching data to View
body: <p>I am trying to pass message using handler to <code>View</code> class; but don't know where I am going wrong. Please correct me. I never used canvas to draw after getting values from Handler.</p>
  
  <p>Thanks in advance!</p>
  
  <p>My log-cat is showing <code>NullPointerException</code> on <code>onDraw</code> method after running this program.And hence line can not be drawn.</p>
  
  <pre><code>public class List extends Activity{
  
  Handler handler=new Handler();
  Message msg=new Message();
  Bundle bundle=new Bundle();
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(new TestView(this));
      bundle.putFloat("x1", 10);
      bundle.putFloat("y1", 10);
      bundle.putFloat("x2", 100);
      bundle.putFloat("y2", 100);
      msg.setData(bundle);
      handler.sendMessage(msg);
  
  }
  
  
  }
  
   class TestView extends View {
  
  Paint p;
  float x1;
  float y1;
  float x2;
  float y2;
  
  public TestView(Context context) {
      super(context);
      Paint p=new Paint();
      p.setColor(Color.BLUE);
      Handler handler=new Handler(){
  
          @Override
          public void handleMessage(Message msg) {
              Looper.prepare();
              Bundle bundle=msg.getData();
              x1=bundle.getFloat("x1");
              y1=bundle.getFloat("y1");
              x2=bundle.getFloat("x2");
              y2=bundle.getFloat("y2");
              Looper.loop();
          }
  
      };
  
  }
  
  
  
  boolean isDrawing=true;
  
  @Override
  protected void onDraw(Canvas canvas) {
  
        canvas.drawLine(x1, y1, x2, y2, p);
  
      invalidate();
  }
  
  
  }
  </code></pre>