Google AutoComplete API getting "INVALID REQUEST" - ios

Question

I've to add google autocomplete api in my app but I don't know. I also getting "INVALID REQUEST". I also check developer.google.com but I can't find any solution. I am using AFNetwrok.
Here is my code
NSString *strURL = [NSString stringWithFormat:#"%#key=%#",AutoComplete_URL,GOOGLE_KEY];
NSDictionary *params = #{#"input" : [#"Paris" stringByReplacingOccurrencesOfString:#" " withString:#"+"],#"sensor":#"true"};
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
[manager POST:strURL parameters:params success:^(AFHTTPRequestOperation *operation, id responseObject) {
if (responseObject) {
[APPDELEGATE hideLoadingView];
if ([[responseObject valueForKey:#"status"] isEqualToString:#"OK"]) {
arrAutocomplete = [[responseObject valueForKey:#"predictions"] valueForKey:#"description"];
NSLog(#"AUTO: %#", arrAutocomplete);
}
else{
// [APPDELEGATE showpToastWithTitle:[response valueForKey:#"msg"]];
//[self.tableView setHidden:YES];
}
}
else{
[APPDELEGATE hideLoadingView];
[APPDELEGATE showToastWithTitle:#"Please check your internet connection"];
}
NSLog(#"JSON: %#", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
[APPDELEGATE hideLoadingView];
[APPDELEGATE showToastWithTitle:#"Something going wrong"];
}];
OUTPUT :-
JSON:
{
predictions = (
);
status = "INVALID_REQUEST";
}

Answer 1

i got it.
NSString *string = [NSString stringWithFormat:#"https://maps.googleapis.com/maps/api/place/autocomplete/json?key=%#&types=geocode&input=%#",GOOGLE_KEY,address];
NSURL *url = [NSURL URLWithString:string];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
// 2
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
operation.responseSerializer = [AFJSONResponseSerializer serializer];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
if (responseObject) {
NSLog(#"%#",responseObject);
}
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
// 4
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Error Retrieving Weather"
message:[error localizedDescription]
delegate:nil
cancelButtonTitle:#"Ok"
otherButtonTitles:nil];
[alertView show];
}];
// 5
[operation start];