Program: 162531
Project: 162531
Buggy source:
public void showButtons(final BottomBarButtonPath buttonPathInterface){
  final String path=buttonPathInterface.getPath();
  if (buttons.getVisibility() == View.VISIBLE) {
    lastUsedArrowButton=0;
    lastUsedFolderButton=0;
    buttons.removeAllViews();
    buttons.setMinimumHeight(pathLayout.getHeight());
    buttonRoot.setImageDrawable(mainActivity.get().getResources().getDrawable(buttonPathInterface.getRootDrawable()));
    buttonRoot.setOnClickListener(new View.OnClickListener(){
      public void onClick(      View p1){
        buttonPathInterface.changePath("String_Node_Str");
        timer.cancel();
        timer.start();
      }
    }
);
    Pair<ArrayList<String>,ArrayList<String>> nameAndPathPair=FileUtils.getPaths(path);
    ArrayList<String> names=nameAndPathPair.first;
    ArrayList<String> rnames=new ArrayList<>(nameAndPathPair.first);
    final ArrayList<String> rpaths=nameAndPathPair.second;
    Collections.reverse(rpaths);
    View view=new View(mainActivity.get());
    LinearLayout.LayoutParams params1=new LinearLayout.LayoutParams(appbar.getToolbar().getContentInsetLeft(),LinearLayout.LayoutParams.WRAP_CONTENT);
    view.setLayoutParams(params1);
    buttons.addView(view);
    for (int i=0; i < names.size(); i++) {
      final int k=i;
      if (rpaths.get(i).equals("String_Node_Str")) {
        buttons.addView(buttonRoot);
      }
 else       if (FileUtils.isStorage(rpaths.get(i))) {
        buttonStorage.setOnClickListener(new View.OnClickListener(){
          public void onClick(          View p1){
            buttonPathInterface.changePath(rpaths.get(k));
            timer.cancel();
            timer.start();
          }
        }
);
        buttons.addView(buttonStorage);
      }
 else {
        Button button=createFolderButton(rnames.get(i));
        button.setOnClickListener(new View.OnClickListener(){
          public void onClick(          View p1){
            buttonPathInterface.changePath(rpaths.get(k));
            timer.cancel();
            timer.start();
          }
        }
);
        buttons.addView(button);
      }
      if (names.size() - i != 1) {
        buttons.addView(createArrow());
      }
    }
    scroll.post(new Runnable(){
      @Override public void run(){
        sendScroll(scroll);
        sendScroll(pathScroll);
      }
    }
);
    if (buttons.getVisibility() == View.VISIBLE) {
      timer.cancel();
      timer.start();
    }
  }
}

Fixed version (ground truth):
public void showButtons(final BottomBarButtonPath buttonPathInterface){
  final String path=buttonPathInterface.getPath();
  if (buttons.getVisibility() == View.VISIBLE) {
    lastUsedArrowButton=0;
    lastUsedFolderButton=0;
    buttons.removeAllViews();
    buttons.setMinimumHeight(pathLayout.getHeight());
    buttonRoot.setImageDrawable(mainActivity.get().getResources().getDrawable(buttonPathInterface.getRootDrawable()));
    buttonRoot.setOnClickListener(new View.OnClickListener(){
      public void onClick(      View p1){
        buttonPathInterface.changePath("String_Node_Str");
        timer.cancel();
        timer.start();
      }
    }
);
    String[] names=FileUtils.getFolderNamesInPath(path);
    final String[] paths=FileUtils.getPathsInPath(path);
    View view=new View(mainActivity.get());
    LinearLayout.LayoutParams params1=new LinearLayout.LayoutParams(appbar.getToolbar().getContentInsetLeft(),LinearLayout.LayoutParams.WRAP_CONTENT);
    view.setLayoutParams(params1);
    buttons.addView(view);
    for (int i=0; i < names.length; i++) {
      final int k=i;
      if (paths[i].equals("String_Node_Str")) {
        buttons.addView(buttonRoot);
      }
 else       if (FileUtils.isStorage(paths[i])) {
        buttonStorage.setOnClickListener(new View.OnClickListener(){
          public void onClick(          View p1){
            buttonPathInterface.changePath(paths[k]);
            timer.cancel();
            timer.start();
          }
        }
);
        buttons.addView(buttonStorage);
      }
 else {
        Button button=createFolderButton(names[i]);
        button.setOnClickListener(new View.OnClickListener(){
          public void onClick(          View p1){
            buttonPathInterface.changePath(paths[k]);
            timer.cancel();
            timer.start();
          }
        }
);
        buttons.addView(button);
      }
      if (names.length - i != 1) {
        buttons.addView(createArrow());
      }
    }
    scroll.post(new Runnable(){
      @Override public void run(){
        sendScroll(scroll);
        sendScroll(pathScroll);
      }
    }
);
    if (buttons.getVisibility() == View.VISIBLE) {
      timer.cancel();
      timer.start();
    }
  }
}