SDK for iOS (legacy)
SDK for iOS is a software development kit for fast integration of the ecommpay payment solutions right in your mobile app for iOS. With SDK for iOS, you can quickly build and offer your customers a fast checkout experience from in your iOS app. In this section you will find information about using SDK for iOS as well as Swift and Objective-C code samples.
Within SDK for iOS 1.9 two versions are available: SDK for iOS 1.9.1 can be embedded in mobile applications running on iOS 11 or above and compatible with XCode 11 or above, while for mobile applications running on iOS 10 and compatible with Xcode 10 SDK for iOS 1.9.0 should be used.
The SDK for iOS libraries can be imported via CocoaPods. For more information, see the Importing libraries via CocoaPods section.
General information
Capabilities
- Apple Pay—purchases in iOS apps. For the detailed information about purchase processing by using the Apple Pay method through SDK for iOS, see Purchases by using alternative payment methods.
- Skrill Wallet—purchases by using e-wallets in all countries.
- DOKU Wallet—purchases by using e-wallets in Indonesia.
- Malaysian Online Banking—purchases by using online banking through Malaysian banks.
- Thai Online Banking—purchases by using online banking through Thai banks.
- Alipay—purchases by using e-wallets in China.
- Neteller—purchases by using e-wallets.
- European Open Banking—purchases by using online banking in the following countries: Austria, Belgium, Estonia, France, Germany, Greece, Hungary, Latvia, Lithuania, the Netherlands, Romania, the United Kingdom.
SDK for iOS also supports payment processing by using methods listed in the Methods section. For information about setup and configuration, contact your ecommpayaccount manager.
- Support for English, French, German, Italian, Spanish and Russian. The language of the payment form can be the one set in the mobile device settings, or the one set by the merchant. In this case you should consider the following:
- If the merchant sets the language supported by SDK for iOS, the payment form is displayed in the language set by the merchant.
- If the merchant sets the language which is not supported by SDK for iOS, the payment form is displayed in English.
- If the merchant does not set the language, the payment form is displayed in the language set in the mobile device settings, if this language is supported by SDK for iOS, or in English, if the language of the mobile device is not supported by SDK for iOS.
- Customisation of payment form (more).
- Support for different ways to enter card data (more):
- manually
- card scanning
- choosing saved card
- using preselected card
- Gathering or passing additional customer data for further analysis (more).
- Clarification of additional parameters required for payment (more).
- Support for 3‑D Secure 2 authentication. 3‑D Secure 2 is a new version of 3‑D Secure (Three-Domain Secure) protocol, which is intended to secure e-commerce card payments (3‑D Secure authentication).
- Support for additional attempts to perform payments (more).
- Getting information about the payment. On all pages of the payment form there is an information button; when tapped, this button shows information about the ID, the amount, the date of the payment and payment description.
- Sending receipts to the customer (more).
Contents
SDK for iOS contains the library which is used for developing applications and running them on Apple devices, and code samples in Swift and Objective-C.
Payment workflow
- Your client app creates an instance of payment object with all the necessary checkout details.
- On the basis of the payment object parameters, the back end part of you app generates the signature for checkout request.
- You call a special method of the payment object to have the client app initiate a checkout request and send it to the ecommpay payment platform.
- The ecommpay payment platform processes the checkout request and performs the payment.
- The payment platform sends the payment processing results to the client app.
- The payment platform sends a callback with the payment processing results to the callback URL you specified.
Using SDK for iOS
- Make sure you have you have ready your merchant ID and secret key obtained from ecommpay.
- If your company has never obtained any ID or secret key from ecommpay, you need to submit an application for connecting to the ecommpay payment platform.
- If your company already has an ID and a secret key to sign messages obtained from ecommpay, you need to notify ecommpay customer support that you want to use SDK for iOS and consult with the customer support on how to arrange a test run.
- Integrate the ecommpay payment solution in your app:
- Implement the checkout request signing functionality on the back end side of your mobile app.
- Download the SDK for iOS library.
- Import the SDK for iOS library into your client app and implement the following functionality: collection of payment details, preparation of data for signing checkout request, opening payment form, and submitting request to the payment platform for payment results.
- Test and put in production mode.
- Request test card numbers and test merchant ID from ecommpay and debug and test your app.
- Once testing is complete, request your production merchant ID from ecommpay and put your app in production mode.
With any questions regarding usage of SDK for iOS contact ecommpay technical support service.
Payment form interface
Signature generation
To verify data integrity and authenticate the messages your application exchange with the ecommpay payment platform, all the messages need to be signed. You must sign all your outgoing messages (for example, checkout request) and check signatures of all the incoming messages (for example, callbacks). Before generating signature, you need to prepare the payment data by packing all the payment parameters into a single string. The string is generated on the client side where you can use SDK for iOS for this purpose. The signing process requires the secret key provided by ecommpay therefore the signing procedure must be performed on the back end side of your app.
- Generate the HMAC value based on the SHA-512 hashing algorithm and your secret key.
- Encode the result of step1 using Base64.
- Input data
- Sample string to sign:
customer_id:5;payment_amount:30;payment_currency:EUR;payment_id:payment1;project_id:115
- Sample secret key:
12345
- Sample string to sign:
-
Result: generated signature
pVmAtGFBQJD2NgLToP1B2elR4QROiYGi3IobPD9PFDfrkjBqdSCFgrVSEtebVJUzOUUHX5tPnHQq9RMn61679A==
The signature your back end generates based on the sample string and the secret key must be exactly the same as of the sample generated signature.
We recommend choosing specific implementation of the signing algorithm based on the programming environment you use. For the detailed information about signature generation, see Signature generation and verification.
Adding library in your project
Importing libraries in Swift
- Copy the
ecommpaySDK.xcframework
file in the project folder of you iOS app. - Add the library into your project. When using Xcode 12, you need to do the following:
- Open the target of your project.
- Select .
- Click +.
- Click Add Other.
- Select the
ecommpaySDK.xcframework
file and click Add.
- Add key NSCameraUsageDescription with value
permission is needed in order to scan card
to the Info.plist file. - If your iOS app does not use user location information, add the NSLocationWhenInUseUsageDescription key with the
fraud prevention
value in the Info.plist file.The ecommpay libraries code does not request user location if the request is not initiated by the host app, but the App Store requires that the NSLocationWhenInUseUsageDescription key value is not empty.
If your iOS app requests user location information, you can skip this step.
- If the iOS app does not have permission to save data on the mobile device, add Privacy - Photo Library Usage Description and Privacy - Photo Library Additions Usage Description keys with values to the Info.plist file. The values specified are shown to the customer in the permission request message.
Importing libraries in Objective-C
Listed below are the instructions on how to import a ecommpay library into your iOS app.
- Copy the
ecommpaySDK.xcframework
file in the project folder of you iOS app. - Add the library into your project. When using Xcode 12, you need to do the following:
- Open the target of your project.
- Select .
- Click +.
- Click Add Other.
- Select the
ecommpaySDK.xcframework
file and click Add. - Select Build Settings.
- Set Always embed swift embedded libraries to Yes.
- Add key NSCameraUsageDescription with value
permission is needed in order to scan card
to the Info.plist file. - If your iOS app does not use user location information, add the NSLocationWhenInUseUsageDescription key with the
fraud prevention
value in the Info.plist file.The ecommpay libraries code does not request user location if the request is not initiated by the host app, but the App Store requires that the NSLocationWhenInUseUsageDescription key value is not empty.
If your iOS app requests user location information, you can skip this step.
- If the iOS app does not have permission to save data on the mobile device, add Privacy - Photo Library Usage Description and Privacy - Photo Library Additions Usage Description keys with values to the Info.plist file. The values specified are shown to the customer in the permission request message.
Importing libraries via CocoaPods
Listed below are the instructions on how to import the libraries via CocoaPods.
- Open the Podfile file and add the following strings:
target 'App' do # Pods for App pod 'Paymentpage-sdk-ios', '1.10.0' end
- Add key NSCameraUsageDescription with value
permission is needed in order to scan card
to the Info.plist file. - If your iOS app does not use user location information, add the NSLocationWhenInUseUsageDescription key with the
fraud prevention
value in the Info.plist file.The ecommpay libraries code does not request user location if the request is not initiated by the host app, but the App Store requires that the NSLocationWhenInUseUsageDescription key value is not empty.
If your iOS app requests user location information, you can skip this step.
- If the iOS app does not have permission to save data on the mobile device, add Privacy - Photo Library Usage Description and Privacy - Photo Library Additions Usage Description keys with values to the Info.plist file. The values specified are shown to the customer in the permission request message.
Opening payment form
This section contains samples of payment form invocation code in Swift and Objective-C.
Opening payment form in Swift
To open payment form, do the following:
- Import the library:
import ecommpaySDK
- Declare the
ecommpaySDK
library in you app (for example, inside theviewDidLoad
method):let ecommpaySDK = EcommpaySDK()
- Create an object named
PaymentInfo
with all the required parameters and any number of optional parameters, for example (required parameters are highlighted with bold optional parameters highlighted with italic):let paymentInfo = PaymentInfo(projectID: 10, paymentID: "internal_payment_id_1", paymentAmount: 1999, paymentCurrency: "USD", paymentDescription: "T-shirt with dog print", customerID: "10", regionCode: "US")
Here are the required parameters:
- projectID—project (merchant) ID ecommpay assigned you
- paymentID—payment ID, must be unique within the project
- paymentAmount—payment amount in minor currency units
- paymentCurrency—payment currency code according to ISO-4217 alpha-3
customerEmail
orcustomerPhone
—the customer's phone number or email (at least one of these parameters must be specified for card payments)
Here are the optional parameters:
- recurrentInfo—object with the details of COF purchase (more)
- paymentDescription—payment description (this parameter is available not only to the merchant, but also to the customer; if paymentDescription is specified in the request, it is visible to the customer in the payment form (in the dialog box containing information about the payment); if this parameter is not specified in the request, it is not visible to the customer)
- customerID—customer ID
- regionCode—customer country
- token—card token
- action—action type (
Sale
(by default),Auth
,Tokenize
, orVerify
) - forcePaymentMethod—the identifier of the payment method which is opened to the customer without an option for the customer to select another payment method. The list of codes is provided in the Payment method codes section
- hideSavedWallets—hiding or displaying saved payment instruments in the payment form. Possible values:
true
—saved payment instruments are hidden, they are not displayed in the payment formfalse
—saved payment instruments are displayed in the payment form
- ECMPScreenDisplayMode—object to manage display of the final page of the payment form and hide the final page if necessary. The following parameters can be passed in the object:
hide_success_final_page
—the final page with the message about the performed payment is not displayed in the payment form.hide_decline_final_page
—the final page with the message about the declined payment is not displayed in the payment form.
The following is an example of specifying the
hide_success_final_page
andhide_decline_final_page
parameters in the request:// Init ECMPPaymentInfo paymentInfo.addEcmpScreenDisplayMode(value: "hide_success_final_page") .addEcmpScreenDisplayMode(value: "hide_decline_final_page")
- Pack all the payment parameters into a string for signing:
paymentInfo.getParamsForSignature();
- Send the string to your back end.
- Have your back end generate the signature on the basis of the string and your secret key.
- Add signature in your
PaymentInfo
object:paymentInfo.setSignature(value: signature)
- Open the payment form by using the following code:
ecommpaySDK.presentPayment(at: self, paymentInfo: paymentInfo) { (result) in print("ecommpay finished with status \\(result.status.rawValue)") if let error = result.error { // if error occurred print("Error: \\(error.localizedDescription)") } if let token = result.token { // if tokenize action print("Token: \\(token)") } }
Before opening the payment form, the library check for any errors and opens the payment form only if no errors occur. Otherwise, the payment form is not opened and the presentPayment method returns the error code.
Opening payment form in Objective-C
To open payment form, do the following:
- Import the library:
#import <ecommpaySDK/ECommPayhostsSDK.h>
- Declare the ecommpaySDK library in you app (for example, inside the
viewDidLoad
method).EcommpaySDK *ecommpaySDK = [[EcommpaySDK.h alloc] init];
- Create an object named
PaymentInfo
with all the required parameters and any number of optional parameters, for example (required parameters are highlighted with bold optional parameters highlighted with italic):PaymentInfo *paymentInfo = [[PaymentInfo alloc] initWithProjectID:10 paymentID:@"internal_payment_id_1" paymentAmount:1999 paymentCurrency:@"USD" paymentDescription:@"T-shirt with dog print" customerID:@"10" regionCode:@"US"];
Here are the required parameters:
- projectID—project (merchant) ID ecommpay assigned you
- paymentID—payment ID, must be unique within the project
- paymentAmount—payment amount in minor currency units
- paymentCurrency—payment currency code according to ISO-4217 alpha-3
Warning: Starting August 12, 2024, Visa Rules will be updated to expand the set of parameters mandatory for processing Visa card payments with the 3‑D Secure authentication. In such cases it will be required to specify at least one of the following parameters:customerPhone
orcustomerEmail
. These parameters must be also specified in thePaymentInfo
object.However, it is also recommended that these and a number of other parameters (with the billing address information) are specified for payments made with cards of other card schemes. According to Visa, rigorous use of these parameters can significantly increase payment acceptance rates (up to 6 %) and drastically decrease the number of operations flagged as fraudulent after they have been processed (up to 65 %). Parameters with the billing address information of the customer include the country code in ISO 3166-1 alpha-2 (
billingCountry
), the postal code (billingPostal
), the city (billingCity
), and the street address (billingAddress
).Here are the optional parameters:
- recurrentInfo—object with the details of COF purchase (more)
- paymentDescription—payment description (this parameter is available not only to the merchant, but also to the customer; if paymentDescription is specified in the request, it is visible to the customer in the payment form (in the dialog box containing information about the payment); if this parameter is not specified in the request, it is not visible to the customer)
- customerID—customer ID
- regionCode—customer country
- ActionType—action type (
Sale
(by default),Auth
,Tokenize
, orVerify
) - token—card token
- forcePaymentMethod—the identifier of the payment method which is opened to the customer without an option for the customer to select another payment method. The list of codes is provided in the Payment method codes section
- hideSavedWallets—hiding or displaying saved payment instruments in the payment form. Possible values:
true
—saved payment instruments are hidden, they are not displayed in the payment form.false
—saved payment instruments are displayed in the payment form.
- ECMPScreenDisplayMode—object to manage display of the final page of the payment form and hide the final page if necessary. The following parameters can be passed in the object:
hide_success_final_page
—the final page with the message about the performed payment is not displayed in the payment form.hide_decline_final_page
—the final page with the message about the declined payment is not displayed in the payment form.
The following is an example of specifying the
hide_success_final_page
andhide_decline_final_page
parameters in the request:// Init ECMPPaymentInfo [paymentInfo addEcmpScreenDisplayMode: hide_success_final_page]; [paymentInfo addEcmpScreenDisplayMode: hide_decline_final_page];
- Pack all the payment parameters into a string for signing:
paymentInfo.getParamsForSignature();
- Send the string to your back end.
- Have your back end generate the signature on the basis of the string and your secret key.
- Add signature in your
PaymentInfo
object:[paymentInfo setSignature:signature];
- Open the payment form by using the following code:
[self.ecommpaySDK presentPaymentAt:self paymentInfo:paymentInfo completionHandler:^(ECPPaymentResult *result) { NSLog(@"ecommpaySDK finished with status %ld", (long)result.status); if(result.error != NULL) { // if error occurred NSLog(@"Error: %@", result.error.localizedDescription); } if(result.token != NULL) { // if tokenize action NSLog(@"Token: %@", result.token); } }];
Before opening the payment form, the library check for any errors and opens the payment form only if no errors occur. Otherwise, the payment form is not opened and the presentPayment method returns the error code.
Response processing
To receive and process response with the payment processing results you need to add the following code:
The result code is returned in the paymentStatus parameter.
The following table lists possible response codes returned in the paymentStatus parameter.
Value in paymentStatus | Description |
---|---|
0 | Checkout successfully completed. |
100 | Operation was declined, for example because of insufficient funds. |
301 | Operation was cancelled by the customer. |
501 | An internal error occurred. You may need to contact technical support. |
Callbacks
Overview
When using SDK for iOS, the merchant can receive callbacks that are sent by the payment platform directly to merchant web service and callbacks that are first sent by the payment platform to SDK for iOS and then by SDK for iOS to merchant mobile application. In the former case, the parameters sent in callbacks may vary depending on the configurations (more). In the latter case, specific set of parameters is provided—the data about status, type and ID of the payment, currency and amount of the payment as well as the payment method that was used:
{
"payment": {
"status": "success",
"type": "purchase",
"id": "12345",
"date": "2020-09-11T14:49:18+0000",
"method": "card",
"sum": 1000,
"currency": "USD"
}
}
The following sections provide information about these callback messages.
Callbacks sent by the payment platform
The payment platform sends all the callback messages to the callback URL you specify. You need to contact the ecommpay technical support and provide the URL to send callbacks. For more information about callbacks, see Callbacks.
Callbacks sent by SDK for iOS
Merchant mobile application can receive callback messages with information about purchase processing result from SDK for iOS as information about payment processing result is sent to SDK for iOS by the payment platform. The callback message is sent to the merchant before the page with information about the result is displayed to the customer on the payment form.
To obtain information about payment result, you need to use the ECMPCallback public protocol. This protocol involves the use of the onPaymentResult method which comes into action automatically as the final payment status is received and, as a result, the merchant receives information about the payment result. To obtain information about the purchase processing result, you can use the following examples of the code with no additional setup; if needed, you can also change the code.
Managing card data
When paying with a payment card, the customer needs to enter the card data on the payment form. In addition to the traditional data entry method (manually), SDK for iOS allows to scan a card, use a saved card or a card token for payment.
Checkout by using stored checkout credentials
You can offer your customers an option to save credentials of cards used for checkout. Your customers will be able to save one or more cards and reuse them for any further purchases without specifying the card details—the customer will be only asked to enter CVV for the current card.
To allow customer to save card credentials and use them later for checkout, you need to set the customerID parameter with ID of the card owner. All the saved cards will be associated with this customer ID and the list of all the saved cards will be shown to your customer during checkout procedure. If the customer decides to delete a saved card, the SDK for iOS library will send the corresponding request to the payment platform to remove the card from the list of saved cards.
Checkout by using tokens
By using the SDK for iOS library, you can implement token-based checkout. Before using the token-based checkout functionality, you need to implement storing payment card credentials and its token on your back end. Each time you initiate a token-based checkout, you need to set the token parameter of your payment object:
Do not forget to include the parameter in your signature generation procedure. You customer will see the payment form with the preselected card with all its credentials, except for CVV, entered in the corresponding fields.
Automatic token generation
Token generation by request
Tokenize
as action type:The generated token and the time it was created at are returned in the token generation response.
Checkout
One-step purchase
By default, SDK for iOS uses one-step purchases (action type Sale
). This type of checkout works right out-of-the-box and requires no additional setup.
Two-step purchase
SDK for iOS supports two-step purchases in which payment is performed in two steps.
- Before opening the payment form, set the action type parameter in the payment object to
Auth
: - Capture payment by using Dashboard or sending payment capture request to the /v2/payment/card/capture endpoint.
For more information about two-step purchases, see Authorisation hold.
COF purchases
ecommpay allows you to perform COF purchases. There are three types of COF purchases: OneClick, auto payments and regular payments. For more information about COF purchases, see Overview.
sale
, auth
and verify
operations and is supported only for purchases by using payment cards.RecurrentInfo
object with the following parameters:- type—type of COF purchase (
.OneClick
,.Regular,
or.Autopayment
) - expiryDay—last day of the payment period
- expiryMonth—last month of the payment period
- expiryYear—last year of the payment period
- period—payment period
- time—time or COF purchases
- startDate—date to initiate the first payment
- scheduledPaymentID—payment ID, must be unique within your project
- Amount of COF purchase. By default the amount of COF purchase is equal to payment amount. To change it, set:
- Data and amount of COF purchase. By default the debit of funds is strictly fixed in time and amount. To customize schedule for COF purchases, set:
RecurrentInfo
object into the PaymentInfo
object.Card verification
The card verification is used when it is necessary to check the customer's card without debiting the funds, as well as to save the card data for future use. With card verification, a zero amount is debited from the card.
Verify
as action type:Purchases by using alternative payment methods
General information
SDK for iOS supports the following alternative payment methods: Apple Pay, Skrill Wallet, DOKU Wallet, Malaysian Online Banking, Thai Online Banking, Alipay, Neteller and purchases by using online banking in European countries. Each of these payment methods is described in a separate topic. Payment processing flow through SDK for iOS using these payment methods can be divided into two types: the first type involves confirmation of payment processing by the alternative payment method service without redirecting the customer to this service (this is relevant only for Apple Pay), and the second type involves redirecting the customer to the alternative payment method service for payment confirmation and processing (this is relevant for other alternative payment methods). Diagrams showing both of these types are provided below along with the description of special features of using the Apple Pay.
To enable support for purchases by using alternative payment methods, contact the ecommpay technical support.
Apple Pay
In order to implement payment processing which involves the Apple Pay payment method, it is necessary to do the following:
- Register merchant's identifier (Merchant ID) with Apple. Merchant ID allows the merchant to accept payments involving the Apple Pay method. This ID never expires, and can be used in multiple websites and iOS applications. For more information see Apple documentation: Create a merchant identifier.
- Create Payment Processing Certificate. This certificate is associated with Merchant ID and is used to secure transaction data when processing payments that involve the Apple Pay method. For more information see Apple documentation: Create a payment processing certificate.
- Send Payment Processing Certificate to the ecommpay technical support using the agreed security methods.
- Enable the Apple Pay capability for the mobile application in the programming environment. For information about enabling Apple Pay capability in Xcode environment see Apple documentation: Enable Apple Pay
Once these steps are completed, it is possible to process payments involving the Apple Pay payment method. The main procedures, such as opening the payment form, processing response and callbacks, are performed the same way as when other alternative payment methods are used, but you also need to consider the following:
- Merchant's identifier (Merchant ID) must be specified. This can be done as follows:
Swift
paymentInfo.setApplePayMerchantID(merchantID: "merchant.example.com")
Objective-C
[paymentInfo setApplePayMerchantID:@"merchant.example.com"];
- The currency of purchase can be EUR, GBP, USD.
- For the Apple Pay payment session to start correctly, it is strongly recommended to set the country code for regionCode parameter (according to ISO 3166 alpha‑2). The specified country code must correspond to the customer's location.
- If needed, additional information about payment can be added to the authorization page of the Apple Pay payment sheet by using the applePayDescription parameter. The information to be added must be specified as the value of this parameter and will be displayed in the Pay field on the Apple Pay payment sheet (this is applicable to the
sale
,auth
andverify
operation modes of the payment form). For the correct display of information, it is recommended to specify the value of the applePayDescription parameter briefly. The usage of the applePayDescription parameter is optional, and if it is not specified in the request, in the Pay field the value of the paymentID parameter is displayed.
Payment involving the Apple Pay payment method is processed as follows.
Registration of COF purchases involving the Apple Pay method is also supported. For more information about the required parameters as well as Swift and Objective-C code samples see the COF purchases section.
Other alternative payment methods
The full sequence of the purchase process involving redirection to the alternative payment method service is provided below.
Gathering customer data
Usually payment form requires a minimum of data to complete a request for payment. However, in order to gather more extensive data and statistics about customers you can send and/or request additional data about your customers, such as customer phone number or email. For more information, see Collecting customer data.
paymentInfo
object:
Customisation
- use pre-defined themes (light and dark)
- set the custom value to any available setting
Using pre-defined themes
SDK for iOS allows to choose between two pre-defined themes (light and dark) of payment form. By default SDK for iOS uses light theme.
Changing settings
overlayColor
— the color of the overlaybackgroundColor
— the color of the background of the payment formheadingTextColor
— the color of the headingmenuTextColor
— the text color of the buttons in the heading of the modal windowfieldTextColor
— the text color of additional fields, payment methods names, text on the page with information about the resultsupportiveTextColor
— the color of the additional textfieldPlaceholderTextColor
— the color of the placeholder textsfieldImageTintColor
— the color of the icons of the CVV field and payment data fields for payment with a new cardfieldTextCorrectColor
— the color of the text if validation of the completed field is successfulfieldTextWrongColor
— the color of the text if validation of the completed field failsfieldBackgroundColor
— the color of the buttons of payment systems and CVV fieldprimaryTintColor
— the main color of buttons and icons of the payment form,secondaryTintColor
— the secondary color of the payment form,lineColor
— the color of the field borders on the page with fields for payment with a new cardactionButtonDisableBackgroundColor
— the color of the disabled action buttonactionButtonDisableTextColor
— the color of the text on the disabled action buttonactionButtonTextColor
— the color of the text on the action buttonshowShadow
— enables shadow for payment methods and saved cards on the page of payment method selectionshowDarkKeyboard
— enables dark theme for the keyboardshowDarkNavigationBar
— enables dark theme for the navigation barshowLightLogo
— enables light logos when using dark theme