Props colors not working 

I try to change the color or ActivityIndicator with the property colors, and seems that not working
my code:
```
 <PTRView onRefresh={this.refresh.bind(this)} colors={'#f43e69'}>
 <View style={{ height:'auto', width:'100%'}}>
                    {this.props.children}
                </View>
  </PTRView>

```