title: show app widget selection list
body: <p>How to open app widget installation list that usually opens by users ?</p>
  
  <p>long click on home screen and open wdget , I want to show this list .</p>
  
  <p>I know this codes run when I user opens widget selection :</p>
  
  <pre><code>Starting activity: Intent { act=android.appwidget.action.APPWIDGET_PICK cmp=com.android.settings/.AppWidgetPickActivity (has extras) }
  
  Displayed activity com.android.settings/.AppWidgetPickActivity: 470 ms (total 470 ms)
  </code></pre>
  
  <p>I assume which extras used for list ?
  thanks</p>