DevFright

iOS devices have several sensors built in that you can make use of in your app. One of them is the digital compass which is also known as a magnetometer. In todays tutorial I want to show you how how you can access the data so that you can use it in your app. The app will be very simple and will just use 8 UILabels with 4 of them being updated with various values.

To begin with, create a new project in Xcode and choose a Single View Application. If you are not sure how to do this, take a look at my post called Setting up your First iOS Xcode Project which will get you to a fresh start and ready to create the app.

The next step is to drag our 8 UILabels. Put four of them down the left side of the screen and the other four down the right side as pictured here (aligning the text on the right hand labels to the left). Change the names to something like seen in the screen shot. You do not have to set the right hand set at zeros… anything will do, including blank UILabels.

Next, click on the middle Editor button (top right) to create a split to allow two files to be opened. On the left, click the Storyboard. The ViewController header file should then appear on the right.

At the top of the header file, import CoreLocation and also add the CLLocationManagerDelegate as follows:

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#import <corelocation /CoreLocation.h>
 
@interface ViewController : UIViewController <cllocationmanagerdelegate></cllocationmanagerdelegate></corelocation>

The first of these two lines indicates that we will be using some of the CoreLocation framework. The allows this ViewController to receive updates when they are available. [Read more...]

A popular method used from the CLLocationManagerDelegate protocol is - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation which allows your app to receive updates when any location changes are detected. The new location details were stored in the newLocation which is a CLLocation.

When iOS 6 launched, that method was deprecated with a suggestion to use a newer version called - (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations or in short locationManager:didUpdateLocations:.

This quick tutorial has been created to explain how to handle a deprecated method, what should be done about it and where you can find out more details about the changes. If you want to know how to use the newer locationManager:didUpdateLocations: method then take a look at the didUpdateLocations tutorial that explains how to work with the NSArray provided by that method.

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A quick tutorial today. I was recently asked how to get a timestamp from a CLLocation object, particularly when the -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations method was used in the CLLocationManagerDelegate protocol. As with most programming solutions, there’s always more than one way to accomplish this. Today, I’ll show you one of the ways it can be done.

Assuming you have your CLLocationManagerDelegate all configured correctly and that you also have your CLLocationManager, this is one way you can get the timestamp from the CLLocation update. [Read more...]

When iOS 6 launched last year, Apple deprecated a commonly used method from the CLLocationManagerDelegate protocol. The method deprecated is - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation and is used to tell the delegate that a new location is available. Each time a location change is detected, this method is called and within the method, you can trigger certain methods or updates to happen as needed.

This was done by using the (CLLocation *)newLocation details. With this method being deprecated in iOS 6, Apple recommends you now use a newer method called - (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations. Rather than providing a newLocation as a CLLocation, this new method returns an NSArray of locations. As the value is a different type, you will need to modify your code to account for the data being handed back in an NSArray.

The good news is that according to the documentation, you still get a CLLocation object, but instead of accessing it direct, you need to pull it out of the NSArray to action it. Lets take a look at some code that will help you do just that. [Read more...]

iOS developers get access to a number of frameworks to help them develop apps. One of the frameworks I like to use is Core Location, often joined with MapKit. The tutorial today will focus on just the Core Location framework and later in the series, we’ll add MapKit to the project so that you can mark your location on a map.

For the project, I’ll be developing for iOS 6 using Storyboards as well as ARC. So lets get going:

Creating the Project

First, lets create a new project by opening Xcode and clicking File > New > Project. I often opt for an empty application, but in this instance I’ll choose a Single View Application because this is all we need to demonstrate a way of working with Core Location.

[Read more...]