import
  import android.view.inputmethod.*;

Variablen Deklaration
  public InputMethodManager in=null;

onCreate
  in = (InputMethodManager) this.getSystemService(this.INPUT_METHOD_SERVICE);

Button OnClick
  in.hideSoftInputFromWindow(tresult.getApplicationWindowToken(),InputMethodManager.HIDE_NOT_ALWAYS);


Hide Tastatur, Anklicken grünen Haken
  tresult.setOnEditorActionListener(new TextView.OnEditorActionListener() {
      @Override
      public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
         if (actionId == EditorInfo.IME_ACTION_GO){
            // auf goEvent
            return true;
         }

         if (actionId == EditorInfo.IME_ACTION_NEXT){
            // auf goEvent
            return true;
         }

         if (actionId == EditorInfo.IME_ACTION_SEND){
             // auf goEvent
             return true;
         }

         if (actionId == EditorInfo.IME_ACTION_DONE){  // grüne Haken
             //MainActivity.in.hideSoftInputFromWindow(tnumber3.getApplicationWindowToken(),InputMethodManager.HIDE_NOT_ALWAYS);
             bntest_Click(null);
             return false;
         }

         return false;
     }
  });