Migrate from 3.x to 4.x

This guide explains how to migrate your Scandit SDK for the Web implementation from 3.x to 4.x.

Overview

There were two breaking changes between 3.x and 4.x as stated in our release notes:

• Removed ScanditSDK.configure()'s preloadCameras and preloadEngineLibrary options and ScanditSDK.loadEngineLibrary() function. Their functionality has been superseded by the (already previously existing) better possibility of calling ScanditSDK.CameraAccess.getCameras() (camera preloading) or creating and reusing a BarcodePicker/Scanner object in the background (engine library preloading); as explained in the README file.
• Replaced CameraSettings.ResolutionPreference numerical enumeration values in favor of string values for optional easier JavaScript usage (ex. CameraSettings.ResolutionPreference.FULL_HD is now "full-hd" instead of 0).

You will find below a more detailed description of how to change your code for each of these changes:

• ScanditSDK.configure() options
• CameraSettings.ResolutionPreference enumeration

ScanditSDK.configure() options

The preloadEngineLibrary and preloadCameras options for the configure() function became obsolete and should be replaced by other (better performing) means. The options are ignored if they are still passed in newer versions of the library.

Old 3.x code:

ScanditSDK.configure(licenseKey: "my_license_key", {
  engineLocation: "build/",
  preloadEngineLibrary: true,
  preloadCameras: true
})

New 4.x code:

ScanditSDK.configure(licenseKey: "my_license_key", {
  engineLocation: "build/"
})

If you used preloadCameras: false or preloadEngineLibrary: false, then nothing needs to be done.

If you used preloadCameras: true, you can achieve the same behavior in 4.x by calling wherever needed in your code the following (only needed once, before a barcode picker is created):

ScanditSDK.CameraAccess.getCameras()

This will ask user permission if needed and cache the list of available cameras for later use.

If you used preloadEngineLibrary: true, you can achieve similar results (actually much better regarding speed optimization) in 4.x by creating a background (hidden and paused) BarcodePicker after the ScanditSDK.configure() function has resolved and using it later when needed. This is the recommended way to use the library and preload resources whenever a BarcodePicker is not immediately needed. A simple example follows:

var barcodePicker = ScanditSDK.BarcodePicker.create(
  document.getElementById("scandit-barcode-picker"),
  {
    accessCamera: false,
    visible: false
  }
);
[...]
barcodePicker.accessCamera().then(function() {
  barcodePicker.setVisible(true);
});

For instant scanning capabilities you could also instead do the following (keeping the camera active all the time):

var barcodePicker = ScanditSDK.BarcodePicker.create(
  document.getElementById("scandit-barcode-picker"),
  {
    scanningPaused: true,
    visible: false
  }
);
[...]
barcodePicker.resumeScanning().then(function() {
  barcodePicker.setVisible(true);
});

Please refer to the readme file and main documentation for more details. For a sample application, please refer to the example_background.html file included in the library.

CameraSettings.ResolutionPreference enumeration

If you used the CameraSettings.ResolutionPreference enumeration by using (as recommended) its members like CameraSettings.ResolutionPreference.HD, then nothing needs to be done.

If you used CameraSettings.ResolutionPreference mapped enumeration values directly (not recommended) by using numbers like 1, then your code needs to be changed to use the needed enumeration members like CameraSettings.ResolutionPreference.HD or its new string mapped values like "hd".