title: Android setOnClickListener(this) Error
body: <p>I have created a button in my Android application &amp; I tried to set onclick listner to run  onClick method like follows </p>
  
  <pre><code>...
  Button btn_ok;
      btn_ok = (Button)findViewById(R.id.button1);
      btn_ok.setOnClickListener(this);
  
  
  }
  public void onClick() {
       EditText uN = (EditText) findViewById(R.id.EditText04);
       uN.setText("Clicked!");
      }
  </code></pre>
  
  <p>But Eclipse shows an error &amp; says that "setOnClickListener" need to Cast Argument. After casting it is like this</p>
  
  <pre><code>btn_ok.setOnClickListener((OnClickListener) this);
  </code></pre>
  
  <p>Then when I'm running the program Emulator says that "Program has stopped unexpectedly"...
  How can I solve this problem ? </p>