Apps Problem with AlarmManager

Hello !

I have little problem with AlarmManager.

class starting alarm
[HIGH]
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_ustawienia);
Bundle bundle = getIntent().getExtras();
int T_ID = bundle.getInt("ID");
ID = T_ID;


Potwierdz = (Button)findViewById(R.id.Nowy);
lista = (ListView)findViewById(R.id.Lista);
context = getApplicationContext();
rowItems = new ArrayList<RowBeanUstawienia>();

Vprzerwij = (Button)findViewById(R.id.button1);

Vprzerwij.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intentstop = new Intent(UstawieniaActivity.this,ZrobZdjecia.class);
PendingIntent senderstop = PendingIntent.getActivity(UstawieniaActivity.this,0, intentstop, 0);
AlarmManager alarmManagerstop = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmManagerstop.cancel(senderstop);

}
});


...
...
final RowAdapterUstawienia adapter = new RowAdapterUstawienia(this,R.layout.custom_row_opis, rowItems);
lista.setAdapter(adapter);

//final InputMethodManager mgr = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
//InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);

class TimePickHandler implements OnTimeSetListener {
@Override
public void onTimeSet(TimePicker view, int Hour, int Minute) {
if(czas){
UstawRozpGodz = Hour+"."+Minute;
db.updateProjektyHH_rozp(ID,Hour);
db.updateProjektyMin_rozp(ID,Minute);
}
else{
UstawZakoGodz = Hour+"."+Minute;
db.updateProjektyHH_zak(ID,Hour);
db.updateProjektyMin_zak(ID,Minute);
}
WybierzCzas.hide();
if(czas){
UstawGodzRoz(GRozp,rowItems,adapter);
//baza.execSQL("INSERT INTO DB"
}
else{
UstawGodzZak(GZako,rowItems,adapter);

}
}
}


class DatePickHandler implements OnDateSetListener {
@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
if(data){
UstawRozpDate = dayOfMonth + "." + monthOfYear + "." + year;
db.updateProjektyYYYY_rozp(ID,year);
db.updateProjektyMM_rozp(ID,monthOfYear);
db.updateProjektyDD_rozp(ID,dayOfMonth);
}
else{
UstawZakoDate = dayOfMonth + "." + monthOfYear + "." + year;
db.updateProjektyYYYY_zak(ID,year);
db.updateProjektyMM_zak(ID,monthOfYear);
db.updateProjektyDD_zak(ID,dayOfMonth);
}
WybierzDate.hide();
if(data)
UstawDateRozp(DRozp,rowItems,adapter);
else
UstawDateRozp(DZako,rowItems,adapter);

}
}


final Calendar c = Calendar.getInstance();
lista.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,int position, long id) {

switch(position){
...

break;

}

}
});
Potwierdz.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent myIntent = new Intent(UstawieniaActivity.this, ZrobZdjecia.class);
PendingIntent pendingIntent = PendingIntent.getActivity(UstawieniaActivity.this, 0, myIntent, PendingIntent.FLAG_ONE_SHOT);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis()+10000,pendingIntent);
Intent intent = new Intent(context, MainActivity.class);
startActivity(intent);

}
});[/HIGH]layout of class starting alarm
[HIGH]<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#E0FFFF"
android:gravity="start"
tools:context=".Main" >

<ListView
android:id="@+id/Lista"
android:layout_width="match_parent"
android:layout_height="375dp"
android:layout_above="@+id/Nowy"
android:layout_below="@+id/imageView1"
android:layout_centerHorizontal="true"
android:background="#FFF"
android:minHeight="375dp" >

</ListView>

<Button
android:id="@+id/Nowy"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="@+id/imageView1"
android:background="#C0C0C0"
android:minHeight="25dp"
android:text="@string/Potw" />

<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:src="@drawable/ic_launcher"
android:contentDescription="@string/hello_world"/>

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_below="@+id/Lista"
android:layout_toRightOf="@+id/imageView1"
android:background="#C0C0C0"
android:minHeight="25dp"
android:text="@string/Usun" />

</RelativeLayout>
[/HIGH]Alarm reciever
[HIGH]
{

Context context;
Button ZrobZdjecie;
Button StopAlarm;
int ID;
DatabaseHandler db = new DatabaseHandler(this);

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_zrobzdjecia);






}



@Override
public boolean onCreateOptionsMenu(android.view.Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

}
[/HIGH]Everything works fine, but when i click on button - Potwierdz, nothing happend. It should set an Alarm, but it do nothing.

When I use this code in other project, it works fine. Maybe you can tell me, what i'm doing wrong.