This simple iOS app is a sample code for using ScanAPI SDK with a Swift application.
Our Barcode Bluetooth Scanners are using External Accessory Framework. It is
very important to make sure your application info plist file contains in the
Supported External Accessory protocol string array our Scanner protocol string
which is com.socketmobile.chs. In the previous version of Xcode it used to
give an error message in the traces but that is no longer the case with the most
recent version of Xcode.
This SDK uses CocoaPods. If it needs to be installed please check the CocoaPods website for the most current instructions: https://cocoapods.org/
Of course the Socket ScanAPI SDK is also required for this example to work.
The ScanAPI documentation can be found at: http://www.socketmobile.com/docs/default-source/developer-documentation/scanapi.pdf?sfvrsn=2
In order to get this application compiling and working out of the box, it is recommended to unzip the ScanApiSDK-10.x.x.zip file at the same root as the clone of this app, otherwise the relative path set in the project Podfile must be updated to the actual location of the extracted SDK zip file.
ie:
/Documents
/SingleEntrySwift
/ScanApiSDK-10.x.x
Edit the SingleEntrySwift/Podfile and make sure the ScanAPI version matches with the one that has been unzipped.
From a Terminal window, type:
pod installin the SingleEntrySwift directory.
Load the SingleEntrySwift workspace (NOT PROJECT) in Xcode and compile and run.
To recap:
cd ~/Documents
unzip ScanApiSDK-10.2.x.zip -d ScanApiSDK-10.2.x
git clone git@github.com:socketmobile/singleentryswift-ios.git SingleEntrySwift
cd SingleEntrySwift
nano Podfile
pod installThere are 2 ways to include ScanAPI Cocoapods in a Swift project.
If your project includes more than one Cocopods, and in particular, Frameworks
type of CocoaPods, then the Podfile should use the use_frameworks setting.
In this configuration the source files using ScanAPI should include a
import ScanAPI at the beginning of the source file.
There is no need of a Bridging Header file.
Here is an example of such Podfile:
def import_pods
use_frameworks!
pod "ScanAPI", :path=> "../ScanApiSDK-10.3.55"
end
platform :ios, '7.1'
target 'SingleEntrySwift'
import_pods
The source file using ScanApiHelper could look like this:
import UIKit
import ScanAPI
class DetailViewController: UIViewController,ScanApiHelperDelegate {
let noScannerConnected = "No scanner connected"
var scanners : [NSString] = [] // keep a list of scanners to display in the status
var softScanner : DeviceInfo? // keep a reference on the SoftScan Scanner
...
Since ScanAPI CocoaPods is a Objective-C static library, a bridging header file must be specified and should import ScanApiHelper.h file. That bridging header file must be specified in the application project settings.
The source files using ScanApiHelper don't need to include anything in that case. The Bridging Header file could be as simple as this:
#import "ScanApiHelper.h"
In Xcode the debug information format in the build options is set by default to 'DWARF with DSYM file'. This is causing numerous warnings. It is recommended to set it back to 'DWARF' instead.
SingleEntrySwift displays a scanner connection status. When a scanner is connected, its friendly name is displayed. The edit box receives the decoded data from the scanner.
Since the ScanApiHelper is written in Objective-C, a bridging header file is required in order to add ScanAPI into a Swift project. This header file should contain only one line to include ScanApiHelper:
#import "ScanApiHelper.h"
In this simple example the ScanApiHelper is "attached" to the main view controller. This main view controller derives from the ScanApiHelperDelegate protocol and implements some of the delegate methods.
As a showcase, this particular example shows the ScanApiHelper shared feature. The purpose of this feature is to share ScanApiHelper across the view hierarchy without the need to pass between the views an explicit reference to ScanApiHelper. When a view using ScanApiHelper is active, it pushes itself as delegate using the ScanApiHelper pushDelegate method which makes this view active to receive notification from ScanApiHelper. The first notification received in deviceArrival even though other views have already received this notification. This indicates there is a scanner connected to the device. Once the view becomes inactive, then it should call the ScanApiHelper popDelegate to remove itself from receiving notification. At this point the prior view that had pushed its delegate becomes the one receiving the notifications.
This handler opens ScanApiHelper just after pushing the delegate to itself requiring the MainViewController to derive from the ScanApiHelperDelegate protocol. It starts a timer that will consume the asynchronous events coming from ScanApi.
This notification is received only when ScanApiHelper open is complete. From that point on, ScanApiHelper is ready to send a receive to/from ScanApi.
This ScanApiHelperDelegate method is called when a scanner is successfully detected on the host. The scanner can be SoftScan or any other Socket Mobile scanners supported by ScanAPI.
When a scanner is no longer available (disconnected), this delegate is invoked.
There are actually 2 onDecodedData delegates defined in ScanApiHelperDelegate. The second one has the result as arguments and is the recommended one to use.
ScanApiHelper is provided as source code. It provides a set of very basic features like enabling disabling barcode symbologies.
If a needed feature is not implemented by ScanApiHelper, the recommendation is to create an extension of ScanApiHelper and copy paste a feature similar from ScanApiHelper to the extended one.
Following this recommendation will prevent to loose the modifications at the next update.
An example of this ScanApiHelper extension is shown in the ScanApiHelperExtension.swift
For some application it might be required to check the decoded data before letting the user scanning more barcodes. This feature is shown with the code enclosed in #if HOST_ACKNOWLEDGMENT statement.
To activate this feature go to the project settings and in the "Other Swift Flags" rename this "-DNO_HOST_ACKNOWLEDGMENT" to this "-DHOST_ACKNOWLEDGMENT".