How to display specific file on the internal storage in listview android?

I saved some file in my app now I want to show the ones which are ended by .txt on my listview not all of them. Could you please help me?

Here is how I generated my listview:

void ShowSavedFiles(){
    SavedFiles = fileList();

    ArrayAdapter adapter = new ArrayAdapter<String>(this,
                                  android.R.layout.simple_list_item_1,
                                  SavedFiles);

    listSavedFiles.setAdapter(adapter);
}

Here is the solution:

void ShowSavedFiles(){ArrayList<String> filteredList = new ArrayList<String>();
SavedFiles = fileList();

for(String str: SavedFiles) {
    if (str.trim().contains("_cred.txt")) {
                  filteredList.add(str.trim());}
     }
           ArrayAdapter adapter
                = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1,
                filteredList);

        listSavedFiles.setAdapter(adapter);}