ShowMessage.java

/**
* メッセージ表示
*/
private void showMessage(){
  final String KEY_OF_PREFERENCES     = "KEY_OF_PREFERENCES";
  final SharedPreferences preferences = getPreferences(MODE_PRIVATE);
  boolean showMessage                 = preferences.getBoolean(KEY_OF_PREFERENCES, true);

  if(showMessage) {
      new AlertDialog.Builder(MainActivity.this)
              .setMessage("ユーザーへのメッセージを表示")
              .setPositiveButton("OK", null)
              .setNegativeButton("次回から表示しない", new DialogInterface.OnClickListener() {
                  @Override
                  public void onClick(DialogInterface dialog, int which) {
                      SharedPreferences.Editor editor = preferences.edit();
                      editor.putBoolean(KEY_OF_PREFERENCES, false);
                      editor.commit();
                  }
              })
              .show();
  }
}