Toggle checkbox programmatically

Have you tried the following?

@Override
public void onListItemClick(ListView listView, View view, int position, long id) {

    //Invert the checkbox-status        
    ((CheckedTextView) view.findViewById(R.id.text1)).setChecked(!isChecked());

    return;

}   

Programmatically in java code

CheckBox mCheckBox = (CheckBox) findViewById(R.id.checkBox);

mCheckBox.setChecked(true); //to check
mCheckBox.setChecked(false); //to uncheck

In android XML

android:checked="true" //to check
android:checked="false" //to uncheck

as

<CheckBox
    android:id="@+id/checkBox"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:checked="true"
    android:text="Checkbox Item" />

First of all go through my this answer: Android listview with check boxes?

Nice as you want to implement checked/unchecked check boxes in ListView, you just need to implement below lines in getView() method:

 // also check this lines in the above example
ViewHolder holder = (ViewHolder) view.getTag();
holder.checkbox.setChecked(list.get(position).isSelected());

Also check the getView() method for the implementation of event on CheckBox residing inside the ListView:

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View view = null;
    if (convertView == null) {
        LayoutInflater inflator = context.getLayoutInflater();
        view = inflator.inflate(R.layout.rowbuttonlayout, null);
        final ViewHolder viewHolder = new ViewHolder();
        viewHolder.text = (TextView) view.findViewById(R.id.label);
        viewHolder.checkbox = (CheckBox) view.findViewById(R.id.check);
        viewHolder.checkbox
            .setOnCheckedChangeListener(
                new CompoundButton.OnCheckedChangeListener() {

                @Override
                public void onCheckedChanged(CompoundButton buttonView,
                        boolean isChecked) {
                    Model element = (Model) viewHolder.checkbox
                            .getTag();
                    element.setSelected(buttonView.isChecked());
                }
            });
        view.setTag(viewHolder);
        viewHolder.checkbox.setTag(list.get(position));
    } else {
        view = convertView;
        ((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
    }
    ViewHolder holder = (ViewHolder) view.getTag();
    holder.text.setText(list.get(position).getName());
    holder.checkbox.setChecked(list.get(position).isSelected());
    // ......  
}