Redoing the blog reader app in Swift

Question

Sooooo this is for Amit Bijlani and anyone else that might want to help. I was talking to Amit on twitter and told him I was going to redo his Blog reader course in Swift and he told me to post it on the forums, BUT I'm running into some trouble. I'm not getting any syntax errors, but the app is blank when I run it. Console shows that I'm downloading the JSON perfectly fine, I just have no idea why the app won't display it. Below is my code I wrote, any help would be welcomed.

//
//  myTableViewController.swift
//  Itzbizkit
//
//  Created by Havic on 8/31/14.
//  Copyright (c) 2014 Cre8tn Havic. All rights reserved.
//

import UIKit

class myTableViewController: UITableViewController {

    var blogPosts = []

    override func viewDidLoad() {
        super.viewDidLoad()

        let blogUrl:NSURL = NSURL.URLWithString("http://blog.teamtreehouse.com/api/get_recent_summary/")
        let jsonData = NSData(contentsOfURL: blogUrl)
        var error:NSError?
        var dataDictionary = NSJSONSerialization.JSONObjectWithData(jsonData, options: nil, error: &error) as NSDictionary
        println("This the dictionary \(dataDictionary)")

        blogPosts = ["test", "test2", "test3"]

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    // MARK: - Table view data source

    override func numberOfSectionsInTableView(tableView: UITableView!) -> Int {
        // #warning Potentially incomplete method implementation.
        // Return the number of sections.
        return self.blogPosts.count
    }

    override func tableView(tableView: UITableView!, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete method implementation.
        // Return the number of rows in the section.
        return 0
    }


    override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
        let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell

        var blogPost:NSDictionary = self.blogPosts.objectAtIndex(indexPath.row) as NSDictionary
        cell.textLabel.text = blogPosts[indexPath.row]["title"] as NSString
        cell.detailTextLabel.text = blogPosts[indexPath.row]["author"] as NSString

        return cell
    }
    }

Answer 1 · 2014-09-01T13:16:05Z

September 1, 2014 1:16pm

You have to make a couple of changes.

Your 'blogPosts' array doesn't contain any blogPost but "test", "test2", "test3". You have to fill it with the blog posts you downloaded before.

blogPosts = NSArray(array: dataDictionary["posts"] as NSArray)

You misplaced the "self.blogPosts.count". You actually need to place it inside "numberOfRowsInSection" and keep the "numberOfSectionsInTableView" to 1.
(This is optional, it should work without any change) Inside "cellForRowAtIndexPath", you already have the blog post as "blogPost" variable. So, you either delete this line of code (you don't need it) and keep the following lines as they are, either you keep it and change

cell.textLabel.text = blogPosts[indexPath.row]["title"] as NSString
cell.detailTextLabel.text = blogPosts[indexPath.row]["author"] as NSString

to

cell.textLabel.text = blogPost["title"] as NSString
cell.detailTextLabel.text = blogPost["author"] as NSString

Hope it helps!

Answer 2 · 2014-10-01T03:53:43Z

October 1, 2014 3:53am

Thank you Jack Leonard that actually makes me feel good. I thought you was talking to someone else and then I realized I actually started this thread LOL. I don't know about a video, I will try to see if I can make that happen, I hate how I sound lol.

Answer 3 · 2014-09-01T13:47:54Z

September 1, 2014 1:47pm

THANK YOU!!!!

Answer 4 · 2014-09-01T13:49:07Z

September 1, 2014 1:49pm

Hi!

I think you may have the implementations for the numberOfSectionsInTableView and numberOfRowsInSection backwards. You currently have numberOfRowsInSection returning 0, so naturally, you wouldn't see any rows. Try this:

override func numberOfSectionsInTableView(tableView: UITableView!) -> Int {
        // #warning Potentially incomplete method implementation.
        // Return the number of sections.
        return 1;  // Remember that this method defaults to 1, so you can delete this bit if you only need 1 section
    }

override func tableView(tableView: UITableView!, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete method implementation.
        // Return the number of rows in the section.
        return self.blogPosts.count;
    }

Hope that helps!

Answer 5 · 2014-09-01T13:49:29Z

September 1, 2014 1:49pm

So I can just delete

cell.textLabel.text = blogPosts[indexPath.row]["title"] as NSString
cell.detailTextLabel.text = blogPosts[indexPath.row]["author"] as NSString

'''

and it will work?

Answer 6 · 2014-09-01T15:27:14Z

September 1, 2014 3:27pm

Actually you have to replace these lines with the lines i wrote you above and make the other changes to i and Hai Phung mentioned!

Answer 7 · 2014-09-02T00:08:03Z

September 2, 2014 12:08am

Yeah I made all the changes that you suggested Dimitris Sotiris Tsolis it atcually was working without the last changes, but I made those too as you suggested. Thanks again man.

Answer 8 · 2014-09-02T23:05:16Z

September 2, 2014 11:05pm

Me too, now I can finish the project and post it up here for you guys.

Answer 9 · 2014-09-04T00:00:16Z

September 4, 2014 12:00am

So @dimitrissotiristsolis I did not even touch the code and now beta 7 saying that this code is not correct now, please help.

override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
        let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell

        var blogPost:NSDictionary = self.blogPosts.objectAtIndex(indexPath.row) as NSDictionary
        cell.textLabel.text = blogPost["title"] as NSString
        cell.detailTextLabel.text = blogPost["author"] as NSString

        return cell
    }
    }
'''

Answer 10 · 2014-09-04T07:38:01Z

September 4, 2014 7:38am

You need to update your code as follows

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell

    var blogPost:NSDictionary = self.blogPosts.objectAtIndex(indexPath.row) as NSDictionary
    cell.textLabel?.text = blogPosts[indexPath.row]["title"] as NSString
    cell.detailTextLabel?.text = blogPosts[indexPath.row]["author"] as NSString

    return cell
}

Noticed that "textLabel" and "detailTextLabel" properties of the cell are optional and must use them with the ? at the end. Also, notice that the method have to return a UITableViewCell (that's why the ! symbol goes away). Lastly, if you want to get rid of the warnings, remove the ! symbol from "tableView" and "indexPath" parameters in cellForRowAtIndexPath method ("numberOfSectionsInTableView" and "numberOfRowsInSection" too).

Answer 11 · 2014-09-04T11:22:13Z

September 4, 2014 11:22am

May I ask why this worked before and I did not even touch anything and now I got errors? lol.

Answer 12 · 2014-09-04T11:36:10Z

September 4, 2014 11:36am

It's based on how UITableViewDataSource api is designed. I don't know the benefits of changing that but since it's still beta, Apple decided that this approach is better than the previous one.

Answer 13 · 2014-09-04T22:28:57Z

September 4, 2014 10:28pm

Well cheers to you Dimitris Sotiris Tsolis thanks again.

Answer 14 · 2014-09-05T23:41:21Z

September 5, 2014 11:41pm

I know I'm becoming more of a pain then anything with this, but Dimitris Sotiris Tsolis this is also getting annoying to me. It will work fine, I will close the app, then re open Xcode and I will have errors, even if I never touched the code that was working fine the night before. '''iOS required init(coder aDecoder: NSCoder) { fatalError("init(coder:) has not been implemented") } '''

I have NO idea what this means, but Xcode asks me to put it in, which fixes the errors but gives me a thread break. The language of Swish is not the pain it's Xcode right now, HELP!!! lol.

Answer 15 · 2014-09-06T08:38:44Z

September 6, 2014 8:38am

Don't worry, no problem! This method "init(coder aDecoder: NSCoder)" is been called during the initialization of an archived object (e.g. a storyboard's nib files generated during the project's build) and it's been called before the "awakeFromNib" method.

Now, the reason your app crushes, is this line of code

fatalError("init(coder:) has not been implemented")

It basically forces your app to crush giving you a reason (the string parameter). I guess it's been auto generated by the Xcode to tell you "ok, don't forget me! initialize something here, else...i'll crush you!" :P

So, to fix this, just delete this line of code and replace it with the super view' initializer...

required init(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
}

...and i believe you're ok!

Answer 16 · 2014-09-06T14:35:23Z

September 6, 2014 2:35pm

I got rid of the lines of code that was making Xcode ask me to put that in there(probably for the best lol.) I'm trying to figure out how to pull the thumbnail images into the app, for each blog post to have a thumbnail for each.

And for some reason( I will say it's MY fault, I can't get the tableView to not overlap my status bar)

Answer 17 · 2014-09-06T15:03:06Z

September 6, 2014 3:03pm

I believe that if you follow the "objective-c style" pattern Amit showed it'll be easy to convert it into swift code. As for the status bar, don't you have tableViewController embedded in a Navigation Controller? If not, i'd suggest to do it. You will need it either way when if you push a new ViewController to display the blog post to the user.

Answer 18 · 2014-09-06T15:33:17Z

September 6, 2014 3:33pm

What do you mean by "I believe that if you follow the "objective-c style" pattern Amit showed it'll be easy to convert it into swift code."? I'm thinking about restarting this and just taking some of my code that already exists in this and pasting it over into a new project.

Answer 19 · 2014-09-06T15:46:16Z

September 6, 2014 3:46pm

In this video, Amit shows how to handle image download by

check whether the "thumbnail" key has a nil value
fill a NSData object with the contents of a url
convert this object to an UIImage object and set it as "image" property of the cell's imageView

if you follow this approach, you can just convert the objective-c code into swift code.

Answer 20 · 2014-09-06T15:46:28Z

September 6, 2014 3:46pm

I fixed the tableView issue, so yay lol.

Answer 21 · 2014-09-06T17:28:53Z

September 6, 2014 5:28pm

Okay I will re go over the video and try to do it objC style as best as possible, I will be back to bother you later Dimitris Sotiris Tsolis lol.

Answer 22 · 2014-09-28T16:22:22Z

September 28, 2014 4:22pm

I'd love to see a video tutorial on this, looks amazing so far :-)

Welcome to the Treehouse Community

Looking to learn something new?

Marlon Henry

Marlon Henry

Redoing the blog reader app in Swift

22 Answers

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Jack Leonard

Jack Leonard

Marlon Henry

Marlon Henry

Hai Phung

Hai Phung

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Dimitris Sotiris Tsolis

Dimitris Sotiris Tsolis

Marlon Henry

Marlon Henry

Marlon Henry

Marlon Henry

Jack Leonard

Jack Leonard