How to save state of CheckBox after exit?

In my app ,one interface has some checkBoxes,I wish after I exit the interface, the CheckBoxes should maintain the state.So next time I enter it can show what I have done last time.I have used SharedPreferrences to achieve this.

checkbox1.setOnCheckedChangeListener(new OnCheckedChangeListener(){
    public void onCheckedChanged(CompoundButton arg0, boolean isChecked) {
// TODO Auto-generated method stub
Editor editor = getSharedPreferences("syllabus", 0).edit();
editor.putBoolean("cbx1_ischecked", isChecked);
editor.commit();
}
    });
checkbox2.setOnCheckedChangeListener(new OnCheckedChangeListener(){
    public void onCheckedChanged(CompoundButton arg0, boolean isChecked) {
    // TODO Auto-generated method stub
    Editor editor = getSharedPreferences("syllabus", 0).edit();
    editor.putBoolean("cbx2_ischecked", isChecked);
    editor.commit();
    }

});

But it doesn't work. when I return to this page, All checkBox show state that "every item is unselected ".

How can I realize the function I wish?

After put date getSharedPreferences, You have to initialize your checkboz state with this data in onCreate, like below

// onCreate

SharedPreferences settings = getSharedPreferences("syllabus", 0);
Boolean isChecked = settings.getBoolean("cbx1_ischecked", false);
checkbox1.setChecked(isChecked );