<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:id="@+id/layout_main"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:paddingBottom="@dimen/activity_vertical_margin"
 android:paddingLeft="@dimen/activity_horizontal_margin"
 android:paddingRight="@dimen/activity_horizontal_margin"
 android:paddingTop="@dimen/activity_vertical_margin"
 tools:context=".MainActivity" >

 <Button
  android:id="@+id/btn_test_popupwindow"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_centerInParent="true"
  android:text="@string/app_name" />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:background="#000000" >

 <TextView
  android:layout_width="wrap_content"
  android:layout_height="80dp"
  android:text="@string/app_name" 
  android:textColor="#ffffffff"
  android:layout_centerInParent="true"
  android:gravity="center"/>

</RelativeLayout>

public class MainActivity extends Activity {

 private Button mButton;
 private PopupWindow mPopupWindow;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  View popupView = getLayoutInflater().inflate(R.layout.layout_popupwindow, null);

  mPopupWindow = new PopupWindow(popupView, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, true);
  mPopupWindow.setTouchable(true);
  mPopupWindow.setOutsideTouchable(true);
  mPopupWindow.setBackgroundDrawable(new BitmapDrawable(getResources(), (Bitmap) null));

  mButton = (Button) findViewById(R.id.btn_test_popupwindow);
  mButton.setOnClickListener(new OnClickListener() {

   @Override
   public void onClick(View v) {
    mPopupWindow.showAsDropDown(v);
   }
  });
 }
}

mPopupWindow.setTouchable(true);
mPopupWindow.setOutsideTouchable(true);
mPopupWindow.setBackgroundDrawable(new BitmapDrawable(getResources(), (Bitmap) null));

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >

 <translate
  android:duration="250"
  android:fromYDelta="100.0%"
  android:toYDelta="0.0" />

</set>

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >

 <translate
  android:duration="250"
  android:fromYDelta="0.0"
  android:toYDelta="100%" />

</set>

 <style name="anim_menu_bottombar">
  <item name="android:windowEnterAnimation">@anim/menu_bottombar_in</item>
  <item name="android:windowExitAnimation">@anim/menu_bottombar_out</item>
 </style>

public class MainActivity extends Activity {

 private PopupWindow mPopupWindow;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);

  View popupView = getLayoutInflater().inflate(R.layout.layout_popupwindow, null);

  mPopupWindow = new PopupWindow(popupView, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, true);
  mPopupWindow.setTouchable(true);
  mPopupWindow.setOutsideTouchable(true);
  mPopupWindow.setBackgroundDrawable(new BitmapDrawable(getResources(), (Bitmap) null));

  mPopupWindow.getContentView().setFocusableInTouchMode(true);
  mPopupWindow.getContentView().setFocusable(true);
  mPopupWindow.getContentView().setOnKeyListener(new OnKeyListener() {
   @Override
   public boolean onKey(View v, int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_MENU && event.getRepeatCount() == 0
      && event.getAction() == KeyEvent.ACTION_DOWN) {
     if (mPopupWindow != null && mPopupWindow.isShowing()) {
      mPopupWindow.dismiss();
     }
     return true;
    }
    return false;
   }
  });
 }

 @Override
 public boolean onKeyDown(int keyCode, KeyEvent event) {
  if (keyCode == KeyEvent.KEYCODE_MENU && event.getRepeatCount() == 0) {
   if (mPopupWindow != null && !mPopupWindow.isShowing()) {
    mPopupWindow.showAtLocation(findViewById(R.id.layout_main), Gravity.BOTTOM, 0, 0);
   }
   return true;
  }
  return super.onKeyDown(keyCode, event);
 }
}