chckbxAlleTage.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                @Override
                public void onCheckedChanged(CompoundButton buttonView,
                        boolean isChecked) {
                    int childrenCount = listAdapter.getChildrenCount(0);
                    if (chckbxAlleTage.isChecked()) {
                        for (int index = 0; index<childrenCount; index++ )
                        {
                            CheckBox tempchckBx = (CheckBox) (listAdapter.getChildView(
                                    0, index, true,findViewById(R.id.LinearLayout1) , expListView))
                                    .findViewById(R.id.chckBx);
                            tempchckBx.setChecked(true);
                        }
                        AnzahlTage = 7;

                    }else
                        {
                            AnzahlTage = 0;
                        }

                    setEtAnzahlTage();
                }
            });