code: private void showPopupUnchecked(int maxActivityCount) {
          if (mAdapter.getDataModel() == null) {
              throw new IllegalStateException("No data model. Did you call #setDataModel?");
          }
  
          getViewTreeObserver().addOnGlobalLayoutListener(mOnGlobalLayoutListener);
  
          final boolean defaultActivityButtonShown =
              mDefaultActivityButton.getVisibility() == VISIBLE;
  
          final int activityCount = mAdapter.getActivityCount();
          final int maxActivityCountOffset = defaultActivityButtonShown ? 1 : 0;
          if (maxActivityCount != ActivityChooserViewAdapter.MAX_ACTIVITY_COUNT_UNLIMITED
                  && activityCount > maxActivityCount + maxActivityCountOffset) {
              mAdapter.setShowFooterView(true);
              mAdapter.setMaxActivityCount(maxActivityCount - 1);
          } else {
              mAdapter.setShowFooterView(false);
              mAdapter.setMaxActivityCount(maxActivityCount);
          }
  
          IcsListPopupWindow popupWindow = getListPopupWindow();
          if (!popupWindow.isShowing()) {
              if (mIsSelectingDefaultActivity || !defaultActivityButtonShown) {
                  mAdapter.setShowDefaultActivity(true, defaultActivityButtonShown);
              } else {
                  mAdapter.setShowDefaultActivity(false, false);
              }
              final int contentWidth = Math.min(mAdapter.measureContentWidth(), mListPopupMaxWidth);
              popupWindow.setContentWidth(contentWidth);
              popupWindow.show();
              if (mProvider != null) {
                  mProvider.subUiVisibilityChanged(true);
              }
              popupWindow.getListView().setContentDescription(mContext.getString(
                      R.string.abs__activitychooserview_choose_application));
          }
      }
docs: Shows the popup no matter if it was already showing.
  
  @param maxActivityCount The max number of activities to display.