How can BMP180 measure a temperature too?
If you read the data sheet (on the site you point to) you see plenty of references to temperature:


  The BMP180 is designed to be connected directly to a microcontroller of a mobile device via the I 2 C
  bus. The pressure and temperature data has to be compensated by the calibration data of the
  E 2 PROM of the BMP180.


and


  The BMP180 consists of a piezo-resistive sensor, an analog to digital converter and a control unit with EEPROM and a serial I2C interface. The BMP180 delivers the uncompensated value of pressure and temperature. The E 2 PROM has stored 176 bit of individual calibration data. This is used to
  compensate offset, temperature dependence and other parameters of the sensor.


And many many more.