chore: add and ignore ip.txt in ios

[machour]

Description

This one have been making me crazy since day 1: I never was able to run the app on ios simulator without hardcoding my IP in AppDelegate.m like this:

- jsCodeLocation = [[RCTBundleURLProvider jsBundleURLForBundleRoot:@ sharedSettings] "index.ios" fallbackResource:nil];
+ jsCodeLocation = [NSURL URLWithString:@"http://192.168.1.183:8081/index.ios.bundle"];

I discovered today that you can provide a file named ip.txt in Xcode and put the IP there instead:
https://github.com/facebook/react-native/blob/master/React/Base/RCTBundleURLProvider.m#L86

This PR add this empty file to Xcode and to gitignore at the same time, so you are free to put any IP there if needed.

I still need someone with a working setup without hardening the IP to give this a go.

(And git status will finally output nothing for me, and I won't have to google how to revert a commit when I commit my AppDelegate.m file by mistake 😭)

[coveralls]

Coverage remained the same at 44.074% when pulling 32f8396 on machour:ignore-ip.txt into 2111d74 on gitpoint:master.

[chinesedfan]

@machour After reading related codes of RN, I think this file is generated automatically. RN will try to detect the ip and save into ip.txt.

[machour]

@chinesedfan yup, but this was never generated for me :/ writing it manually fix this hassle for me

[chinesedfan]

@machour Hmm, that's weird. I can run the app easily on my iPhone 6Plus. I just need:

• clone the repo and open by Xcode 9.2
• change the bundle identifier and select my personal sign, as well as RN tutorial says
• build and run

[machour]

change the bundle identifier and select my personal sign, as well as RN tutorial says

can you give me a link to read? also, won't changing the bundle id generate modifications that shouldn't be commited?

[chinesedfan]

Sorry, the tutorial is not an official document and is written by Chinese. And yes, don't commit these modifications. I also left some messages for you in Gitter. Hope you can find the root reason.

[machour]

@chinesedfan I tried a lot of things over the past few days, the only thing that allows me to have a clean working copy (nothing to avoid commiting) is this PR.

Any blockers on your side to merge this in?

[chinesedfan]

@machour I am not sure. Because I didn't face this problem.

@gitpoint/maintainers What about you guys think?

[machour]

@chinesedfan, I meant, if you apply this PR locally and try to run the project as you usually do, does it still work for you?

[chinesedfan]

@machour No problem. I can both work normally.

[chinesedfan]

Really magic localhost for @machour. /etc/hosts is correct and ping localhost points to 127.0.0.1. Following links are able to be visited when running the simulator,

• http://127.0.0.1/status
• http://192.168.1.50/status
• http://mbp.local:8081/status

Except this,

• http://localhost:8081/status

Let me merge it to save him. And revert in one day we found the real reason.

[machour]

Thank you!!!! 😭 ❤️