abdus's Blog

Call back blocks are not part of UIAlertView. We need add this functionality to UIAlertView. For this create Category of UIAlertView class that conforms UIAlertViewProtocol. In this category we will add a method that receives completion handler block. (To add methods/functionality to an existing class best practice is to make category of that class. Any methods declared in a category will be available to all instances of the original class). Following would be the steps:

Create Category of UIAlertView say as (AddBlockCallBacks)

Push notifications are useful in sending broadcast messages to all registered receivers. To handle push notifications when arrived in your iOS application is tricky part in order to take their full advantage. Objective of this post is to explain how to handle push notifications when arrived. I assume that reader has already implemented a basic application that can receive push notifications. When push notification arrives, your application can be in

Closed state – App is killed

Running state – App is in Foreground

Suspended state – App is in Background

Lets discuses one by one how to handle them in each state

Closed state:

Understanding appDelegate protocol methods and their order of invocation is important in order to use them effectively. This post defines basic differences between two of the delegate method i.e.

applicationDidBecomeActive

applicationWillEnterForeground

Apparently it seems like these two methods are invoked for same events but there are significant differences that must be understood by every iOS developer.

When waking up i.e. relaunching the app (either through springboard, app switching or URL) applicationWillEnterForeground is called. It is only executed once when app comes to front from background, while applicationDidBecomeActive is called multiple times after launch i will define later in this post.

Facebook released an upgrade of its sdk for iOS i.e. Facebook sdk 3.1. There are significant changes with this upgrade. The major change this post is targeting is

You cannot request multiple permissions (publish_actions, email, basic_info) simultaneously.

com.facebook.sdk error 5 is always irritating while working with Facebook iOS sdk. Most of the times it comes with addional in console Error: HTTP status code:400. Its a perception that there is a bug in Facebook iOS sdk that produces this error randomly. I think this error occurs for some certain reasons and sdk do not provide actual reason of error when it occurs. Some of the cases that i identified are explained further in this post

  Several Possible Reasons

Every request in sdk is accomplished with completion blocks that we actually pass as argument in completionHandler. This error occurs when a block is in progress and made another request. A simple example might be If you have written request to post on Facebook (startForPostStatusUpdate::) on some button action. On single button tap it would work fine but if you double tap on button it will throw this error com.facebook.sdk error 5

Create thumbnail from docx, xls, pptx- There are number of ways for viewing office document files (docx, xls, pptx) in iOS project that opens document in a view where all pages are stacked one after other. What if you need to open document file and display all the pages they have in thumbnail view bar? So that user can navigate through thumbnails and tap on specific to open that in the same view.

If you search it on internet you will only find a clue saying “take screen shot of each page and display in thumbnail bar”.

By default Interface Builder do not provide facility to set custom fonts for UI elements. If you have to use custom fonts in your iOS application there two possible ways

Make IBOutlet of each element and set font programatically by sending setFont message

Create png image for your text and set as background of your UI element.

Appirater is simple library that let you ask your user to rate iPhone app on app store. You can configure the options that when user should be prompted for rating and appirater will show an AlertView to rate.

Configure Project to use Appirater

Download Appirater from Github Repository

Import Appirater to your project (Please note that only .h and .m file is required. Ignore others if your app is not multilingual)

Import CFNetwork and SystemConfiguration frameworks and make them optional

Configure appDelegate.m

In didFinishLaunching method add [Appirater appLaunched:YES];

In didFinishLaunching method set your application ID by [Appirater setAppId:@"appStore appID"];