invariant violation 3a has not been registered react native

1Some Solutions that worked for me:
2I got this issue after renaming the project name and a couple of 
3files. to solve it just make sure that the name of the app is the same in 
4index.js app.json, MainActivity.java and AppDelegate.m.
5
6Solution 1 Inside app.json File:
7{ "name": "MyNewApp", "displayName": "MyNewApp" }
8
9Solution 2 :
10// AppRegistry defines the entry point to the application and provides the 
11// root component. Your first param doesn't match your project name.
12// First param of registerComponent has to be your project name, second param 
13// is anonymous function that returns your root react component.
14// If first param doesn't match xcode project name, you get that error that
15// your application has not been registered.
16Inside index.js File:
17AppRegistry.registerComponent('MyNewApp', () => MyNewApp);
18
19Solution 3:
20Inside MainActivity.java File:
21@Override protected String getMainComponentName() {
22	return "MyNewApp"; 
23}
24
25Solution 4:
26// Be sure that the 'AppName' you pass into the
27// AppRegistry.registerComponent('AppName' /* <- */, ... )
28// matches with the @"AppName" on your AppDelegate.m on the call for
29Inside AppDelegate.m File:
30[[RCTRootView alloc] initWithBundleUrl:...
31                            moduleName:@"AppName" // <-
32                         launchOptions:...