react native and setting up the gmail api

Question

I am having trouble setting up the gmail api. Can anyone tell me where I am going wrong?

Instruction:

Run the following command to download the library using git:

git clone --recursive https://github.com/google/google-api-objectivec-client.git

In the command line I navigated to the root directory of my project and ran that command.

Open Xcode and create a new workspace named "Quickstart".

Using File > Add Files to "Quickstart"..., add the following project to the workspace that you cloned in the previous step:
google-api-objectivec-client/Source/GTLCore.xcodeproj

I did not create a new workspace I simply used the existing one. I clicked file > Add files to "Inbox" and added the GTLCore.xcodeproj

Create a new iOS > Application > Single View Application project named "QuickstartApp", with the organization "com.example". Set the Language to Objective-C, and when saving the project set the Add to and Group fields to "Quickstart".

Since I already have a project I did not do this step.

Add the following frameworks and libraries to the project's Build Phases > Link Binary with Libraries section:
GTL.framework (from GTLiOSCore target)

I clicked on my Inbox project, selected build phases and added the GTL.framework.

Change the following Build Settings:
Add the flag GTL_BUILT_AS_FRAMEWORK=1 to Preprocessor Macros.

I clicked on my Inbox project, clicked build settings, searched for preprocessor macros and added that line of code.

Add the file google-api-objectivec-client/Source/OAuth2/Touch/GTMOAuth2ViewTouch.xib to the project's Supporting Files group.

I selected inboxTests > supporting files, right click add files to inbox however the file is not in that location it is located in

/google-api-objectivec-client/Deps/gtm-oauth2/Source/Touch/GTMOAuth2ViewTouch.xib

Add the following files to the QuickstartApp group:

google-api-objectivec-client/Source/Services/Gmail/Generated/GTLGmail_Sources.m

google-api-objectivec-client/Source/Services/Gmail/Generated/GTLGmail.h

I right click on my inbox folder and selected 'add files to inbox' both of these files were added in my inbox folder.

now at this point try to compile but get an error 'GTLObject.h'file not found

This file is located in the GTLCore.xcodeproj that was added in step 3. Every time I add one of these files it asks for another.

step 4: I created my own files

gmail.h

#ifndef gmail_h
#define gmail_h
#import <UIKit/UIKit.h>

#import "GTL/GTMOAuth2ViewControllerTouch.h"
#import "GTLGmail.h"

@interface gmail : UIViewController

@property (nonatomic, strong) GTLServiceGmail *service;
@property (nonatomic, strong) UITextView *output;

@end

#endif /* gmail_h */

copy and pasted into a new file gmail.m

#import <Foundation/Foundation.h>

#import "gmail.h"

static NSString *const kKeychainItemName = @"Gmail API";
static NSString *const kClientID = @"this is my key";

@implementation gmail

@synthesize service = _service;
@synthesize output = _output;

// When the view loads, create necessary subviews, and initialize the Gmail API service.
- (void)viewDidLoad {
  [super viewDidLoad];

  // Create a UITextView to display output.
  self.output = [[UITextView alloc] initWithFrame:self.view.bounds];
  self.output.editable = false;
  self.output.contentInset = UIEdgeInsetsMake(20.0, 0.0, 20.0, 0.0);
  self.output.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
  [self.view addSubview:self.output];

  // Initialize the Gmail API service & load existing credentials from the keychain if available.
  self.service = [[GTLServiceGmail alloc] init];
  self.service.authorizer =
  [GTMOAuth2ViewControllerTouch authForGoogleFromKeychainForName:kKeychainItemName
                                                        clientID:kClientID
                                                    clientSecret:nil];
}

// When the view appears, ensure that the Gmail API service is authorized, and perform API calls.
- (void)viewDidAppear:(BOOL)animated {
  if (!self.service.authorizer.canAuthorize) {
    // Not yet authorized, request authorization by pushing the login UI onto the UI stack.
    [self presentViewController:[self createAuthController] animated:YES completion:nil];

  } else {
    [self fetchLabels];
  }
}

// Construct a query and get a list of labels from the user's gmail. Display the
// label name in the UITextView
- (void)fetchLabels {
  self.output.text = @"Getting labels...";
  GTLQueryGmail *query = [GTLQueryGmail queryForUsersLabelsList];
  [self.service executeQuery:query
                    delegate:self
           didFinishSelector:@selector(displayResultWithTicket:finishedWithObject:error:)];
}

- (void)displayResultWithTicket:(GTLServiceTicket *)ticket
             finishedWithObject:(GTLGmailListLabelsResponse *)labelsResponse
                          error:(NSError *)error {
  if (error == nil) {
    NSMutableString *labelString = [[NSMutableString alloc] init];
    if (labelsResponse.labels.count > 0) {
      [labelString appendString:@"Labels:\n"];
      for (GTLGmailLabel *label in labelsResponse.labels) {
        [labelString appendFormat:@"%@\n", label.name];
      }
    } else {
      [labelString appendString:@"No labels found."];
    }
    self.output.text = labelString;
  } else {
    [self showAlert:@"Error" message:error.localizedDescription];
  }
}


// Creates the auth controller for authorizing access to Gmail API.
- (GTMOAuth2ViewControllerTouch *)createAuthController {
  GTMOAuth2ViewControllerTouch *authController;
  NSArray *scopes = [NSArray arrayWithObjects:kGTLAuthScopeGmailReadonly, nil];
  authController = [[GTMOAuth2ViewControllerTouch alloc]
                    initWithScope:[scopes componentsJoinedByString:@" "]
                    clientID:kClientID
                    clientSecret:nil
                    keychainItemName:kKeychainItemName
                    delegate:self
                    finishedSelector:@selector(viewController:finishedWithAuth:error:)];
  return authController;
}

// Handle completion of the authorization process, and update the Gmail API
// with the new credentials.
- (void)viewController:(GTMOAuth2ViewControllerTouch *)viewController
      finishedWithAuth:(GTMOAuth2Authentication *)authResult
                 error:(NSError *)error {
  if (error != nil) {
    [self showAlert:@"Authentication Error" message:error.localizedDescription];
    self.service.authorizer = nil;
  }
  else {
    self.service.authorizer = authResult;
    [self dismissViewControllerAnimated:YES completion:nil];
  }
}

// Helper for showing an alert
- (void)showAlert:(NSString *)title message:(NSString *)message {
  UIAlertView *alert;
  alert = [[UIAlertView alloc] initWithTitle:title
                                     message:message
                                    delegate:nil
                           cancelButtonTitle:@"OK"
                           otherButtonTitles:nil];
  [alert show];
}

@end

Answer 1

The documentation states that "the static library target also creates a folder with the library's headers to drag into your target's sources". The corresponding directory contains only one header file GTLDefines.h and it apparently makes no reference to other required ones such as GTLObject.h, nor is there a folder that contains only header files. I think it is necessary to manually add references to other required header files such as Objects/GTLObject.h into the app project.

Try also to look at this link. It states here that he imported headers from the GTL.proj to his project. These include files like GTLBase64.h, GTLBatchQuery.h, GTLBatchResult.h. Without the headers, he gets the error "GTLObject.h file not found." on the import statement.