title: Make bottomSheetDialog full screen over status bar
body: <p>I recently used android.support.design.widget.BottomSheetDialogFragment. I wanted to do something which is similar to the Google contact app, its BottomSheet can overlay the toolbar and statusbar. However, when I use the BottomSheetDialogFragment to implement this, it turns out to this:
  <a href="https://i.stack.imgur.com/vzfz8.png"><img src="https://i.stack.imgur.com/vzfz8.png" alt="My Implementation"></a></p>
  
  <p>As you can see the activity's toolbar is still visible. Here is my code of the <code>BottomSheetDialogFragment</code>:</p>
  
  <pre><code>public class KeyDetailFragment extends BottomSheetDialogFragment {
      private BottomSheetBehavior.BottomSheetCallback mBottomSheetBehaviorCallback = new BottomSheetBehavior.BottomSheetCallback() {
          @Override
          public void onStateChanged(@NonNull View bottomSheet, int newState) {
              if (newState == BottomSheetBehavior.STATE_HIDDEN) {
                  dismiss();
              }
          }
  
          @Override
          public void onSlide(@NonNull View bottomSheet, float slideOffset) {
  
          }
      };
  
      @Override
      public void setupDialog(Dialog dialog, int style) {
          super.setupDialog(dialog, style);
          View contentView = View.inflate(getActivity(), R.layout.sheet_key, null);
          dialog.setContentView(contentView);
          View parent = (View) contentView.getParent();
          parent.setFitsSystemWindows(true);
          BottomSheetBehavior bottomSheetBehavior = BottomSheetBehavior.from(parent);
          contentView.measure(0, 0);
  bottomSheetBehavior.setPeekHeight(contentView.getMeasuredHeight());
  
          CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) parent.getLayoutParams();
          if (params.getBehavior() instanceof BottomSheetBehavior) {
                   ((BottomSheetBehavior)params.getBehavior()).setBottomSheetCallback(mBottomSheetBehaviorCallback);
          }
          params.gravity = Gravity.TOP | Gravity.CENTER_HORIZONTAL;
          parent.setLayoutParams(params);
      }
  }
  </code></pre>
  
  <p>I referred to the source and I found an attribute interests me:</p>
  
  <pre><code>private static int getThemeResId(Context context, int themeId) {
      if (themeId == 0) {
          // If the provided theme is 0, then retrieve the dialogTheme from our theme
          TypedValue outValue = new TypedValue();
          if (context.getTheme().resolveAttribute(
                  R.attr.bottomSheetDialogTheme, outValue, true)) {
              themeId = outValue.resourceId;
          } else {
              // bottomSheetDialogTheme is not provided; we default to our light theme
              themeId = R.style.Theme_Design_Light_BottomSheetDialog;
          }
      }
      return themeId;
  }
  </code></pre>
  
  <p>the attribute <code>bottomSheetDialogTheme</code> here may change the bottom sheet's style but I don't know how to change it, and I doubt whether this would work. Can someone give me solution about achieving it that it can overlay the toolbar and statusbar?</p>