問題：

去除黑色

解決

http://stackoverflow.com/questions/29300732/render-text-box-with-transparent-background-on-top-of-image-in-react-native-ios

 <Image style={{ width: widthSrc, height: 180 }} resizeMode='stretch' source={{ uri: this.props.data.trainID.platImg }}>
    <View style={styles.imageback}>
         <Text style={{ fontSize: 30, color: '#FFFFFF', marginLeft: 15, marginTop: 72 }}>{this.props.data.trainID.name}</Text>
    </View>
</Image>



const styles = StyleSheet.create({
    imageback:{
        backgroundColor: 'rgba(0,0,0,0)',
    },
});