React Native, TouchableOpacity wrapping floating button get nothing

I'm creating a simple action button (floating button)

This is working :

<View style={{
    width: this.props.size,
    height: this.props.size,
    borderRadius: this.props.size / 2,
    backgroundColor: '#ee6e73',
    position: 'absolute',
    bottom: 10,
    right: 10,
    flexDirection:'row'
}}>
    <Text>
        +
    </Text>
</View>

This is not :

<TouchableOpacity
        onPress={()=>{
        }} >
    <View style={{
        width: this.props.size,
        height: this.props.size,
        borderRadius: this.props.size / 2,
        backgroundColor: '#ee6e73',
        position: 'absolute',
        bottom: 10,
        right: 10,
        flexDirection:'row'
    }}>
        <Text>
            +
        </Text>
    </View>
</TouchableOpacity>

Just wrap with TouchableOpacity then my button not show up without any errors.

React 0.1.7, Android

Then I try move styling from View to TouchableOpacity, It's work

<TouchableOpacity
        onPress={()=>{
        }} 
        style={{
            width: this.props.size,
            height: this.props.size,
            position: 'absolute',
            borderRadius: this.props.size / 2,
            backgroundColor: '#ee6e73',
            bottom: 10,
            right: 10,
        }}>
    <Text>
        +
    </Text>
</TouchableOpacity>

Can any one explain me why?

React Native docs said

[https://facebook.github.io/react-native/docs/touchableopacity.html][1]

A wrapper for making views respond properly to touches. This is done without actually changing the view hierarchy, and in general is easy to add to an app without weird side-effects.

This mean I wrap my original view and it would work as I expected, But it's not.