个人中心修改资料清除用户名隐藏删除按钮，review by 于良

@@ -74,9 +74,13 @@ export default class Setting extends React.Component {
                             alignItems: 'center',
                         }}
                     >
-                        <Image
-                            source={require('../../images/user/delete.png')}
-                        />
+                    {nickName.length ? <Image
+                        style={{
+                            display: 'none',
+                        }}
+                        source={require('../../images/user/delete.png')}
+                    /> : null}
+
                     </TouchableOpacity>
 
                 </View>