react-native: how to override the default style defined in a component

The description is a bit vague. Is it a component you wrote your self? Assuming this it should work like this:

export default React.createClass({
  render: function(){
    return(<View style={[ styles.container, this.props.style ]}>...</View>
  }
})

var styles = StyleSheet.create({
  container: {
    backgroundColor: '#ffffff'
  },
});