GUI Funktionen (Berechnung) hNA aus Texfeld nehmen

src/ch/spherIC/recurvebowsight/RBSMainActivity.java

             Double a = Double.valueOf(this.bowPulloutTxtFld.getText().toString()) * 10;
             Double heVs = this.scHeVSSpinner.getVisibility() == View.VISIBLE ? Double.valueOf(this.scHeVSSpinner.getSelectedItem().toString())
                                                                              : Double.valueOf(this.scHeVSTxtFld.getText().toString());
-            Double lhNA = this.selectedArcherySetup.getHNA();
+            Double lhNA = Double.valueOf(this.hNATxtFld.getText().toString());
             Double dltH = (Double.valueOf(this.targetCenterHeightTxtFld.getText().toString())
                            - Double.valueOf(this.arrowNockHeightTxtFld.getText().toString())) * Math.pow(10, 3);
             Double ldistH = Double.valueOf(this.shootingDistanzTxtFld.getText().toString()) * Math.pow(10, 3);