// refresh image button backgrounds
  private void refresh() {
    refreshButtonBackground(
        walkImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "walk.png"));
    refreshButtonBackground(
        standImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "stand.png"));
    refreshButtonBackground(
        punchImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "punch.png"));
    refreshButtonBackground(
        kickImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "kick.png"));
    refreshButtonBackground(
        takeHitImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "take_hit.png"));
    refreshButtonBackground(
        crouchImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "crouch.png"));
    refreshButtonBackground(
        victoryImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "victory.png"));
    refreshButtonBackground(
        defeatImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "defeat.png"));

    refreshButtonBackground(
        hitVoiceImageButton,
        Storage.getOutputMediaFile(InsertMediaToCharacterActivity.this, fighterName, "hit.3gpp"));
    refreshButtonBackground(
        takeHitVoiceImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "take_hit.3gpp"));
    refreshButtonBackground(
        winningVoiceImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "winning.3gpp"));
    refreshButtonBackground(
        victoryVoiceImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "victory.3gpp"));
    refreshButtonBackground(
        defeatVoiceImageButton,
        Storage.getOutputMediaFile(
            InsertMediaToCharacterActivity.this, fighterName, "defeat.3gpp"));
  }