How Do I Update UIWebView After viewDidLoad? - objective-c

Question

This is my first iOS app, so I am probably missing something very simple. Please be kind. I have been tearing my hair out and I could really use some help.
Overview Of App
Basically, this is a single page application that just loads a UIWebView. I have an external accessory (bluetooth barcode scanner) that I connect and basically what I want to do is when the the app receives a scan, I want to call a method in my ViewController and update the UIWebView accordingly.
What Is Working
I am able to connect the scanner, load the first view, which loads the initial webpage, scan a barcode and call the method in my controller.
My Problem
I can't seem to figure out how to update the UIWebView from the method in my controller. It logs the url string to my debugger area, but never actually updates the webview. I am pretty sure I have some delegation wrong or something with my webview instance. There must be some glue code here that I am missing.
My Code HelloWorldViewController.h
#import <UIKit/UIKit.h>
#import "KScan.h"
#interface HelloWorldViewController : UIViewController <UIWebViewDelegate> {
IBOutlet UIWebView *page;
IBOutlet UILabel *myLabel;
Boolean IsFirstTime;
KScan *kscan;
}
- (void)setFirstTime;
- (void)DisplayConnectionStatus;
- (void)DisplayMessage:(char *)Message;
- (void)newBarcodeScanned:(NSString *)barcode;
- (void)loadBarcodePage:(NSString *)barcode;
#property (nonatomic, retain) KScan *kscan;
#property (nonatomic, retain) UIWebView *page;
#property (nonatomic, retain) UILabel *myLabel;
#end
My Code HelloWorldViewController.m
#import "HelloWorldViewController.h"
#import "common.h"
#implementation HelloWorldViewController
#synthesize myLabel;
#synthesize page;
#synthesize kscan;
- (void)setFirstTime
{
IsFirstTime = true;
}
- (void)viewDidLoad
{
self.kscan = [[KScan alloc] init];
[super viewDidLoad];
page.scrollView.bounces = NO;
//page.delegate = self;
[page loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:#"http://192.168.0.187:3000"]]];
}
- (void) newBarcodeScanned:(NSString *)barcode
{
NSLog(#"%s[%#]",__FUNCTION__, barcode);
[self loadBarcodePage:barcode];
}
- (void)loadBarcodePage:(NSString *)barcode
{
NSLog(#"%s",__FUNCTION__);
NSString *url = [[NSString alloc] initWithFormat:#"http://www.google.com/%#", barcode];
NSLog(#"%#", url);
[page loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:url]]];
}
- (void)viewDidUnload
{
[myLabel release];
myLabel = nil;
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation: (UIInterfaceOrientation)interfaceOrientation
{
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
} else {
return YES;
}
}
- (void)dealloc {
[page release];
[kscan release];
[myLabel release];
[super dealloc];
}
#end
Basically, I am just trying to load google.com into my page webview when scanning a barcode. My log statements are being logged with the correct URL, but this line of code doesn't work.
[page loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:url]]];
I am not getting any errors and my xCode debugging skills are not the greatest.
Any help would be greatly appreciated!

Answer 1

It looks like your webview is never allocated, or added to your main view. You are probably talking to a nil instance.
Unless your web view comes from a XIB file (which I doubt since it is not declared as an IBOutlet in your heder file) try adding something like this to your viewDidLoad:
self.page = [[UIWebView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:self.page];