feaet(ios): add optional text footer to payment screens

plugin.xml

@@ -73,6 +73,7 @@
       <source-file src="src/ios/StripePaymentOptions.swift" />
       <source-file src="src/ios/StripePaymentsPluginConfig.swift" />
       <source-file src="src/ios/StripePaymentsPlugin.swift" />
+      <source-file src="src/ios/StripePaymentContextFooterView.swift" />
     </platform>
 </plugin>
 

src/ios/StripePaymentContextFooterView.swift

@@ -0,0 +1,54 @@
+import UIKit
+import Stripe
+
+class StripePaymentContextFooterView: UIView {
+
+    var insetMargins: UIEdgeInsets = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
+
+    var text: String = "" {
+        didSet {
+            textLabel.text = text
+        }
+    }
+
+    var theme: STPTheme = STPTheme.default() {
+        didSet {
+            textLabel.font = theme.smallFont
+            textLabel.textColor = theme.secondaryForegroundColor
+        }
+    }
+
+    fileprivate let textLabel = UILabel()
+
+    convenience init(text: String, align: NSTextAlignment = .center) {
+        self.init()
+        textLabel.numberOfLines = 0
+        textLabel.textAlignment = align
+        textLabel.adjustsFontSizeToFitWidth = true
+        self.addSubview(textLabel)
+
+        self.text = text
+        textLabel.text = text
+
+    }
+
+    override func layoutSubviews() {
+        textLabel.frame = self.bounds.inset(by: insetMargins)
+    }
+
+    override func sizeThatFits(_ size: CGSize) -> CGSize {
+        // Add 10 pt border on all sides
+        var insetSize = size
+        insetSize.width -= (insetMargins.left + insetMargins.right)
+        insetSize.height -= (insetMargins.top + insetMargins.bottom)
+
+        var newSize = textLabel.sizeThatFits(insetSize)
+
+        newSize.width += (insetMargins.left + insetMargins.right)
+        newSize.height += (insetMargins.top + insetMargins.bottom)
+
+        return newSize
+    }
+
+
+}

src/ios/StripePaymentsPlugin.swift

@@ -50,6 +50,8 @@ import Stripe
         PluginConfig.appleMerchantId = dict["appleMerchantId"] as? String ?? ""
         PluginConfig.companyName = dict["companyName"] as? String ?? ""
         PluginConfig.maximumKeyRetries = dict["maximumKeyRetries"] as? Int ?? 0
+        PluginConfig.paymentOptionsFooter = dict["paymentOptionsFooter"] as? String ?? ""
+        PluginConfig.addCardFooter = dict["addCardFooter"] as? String ?? ""
 
         if let headersDict = dict["extraHTTPHeaders"] as? [String:String] {
             PluginConfig.extraHTTPHeaders = headersDict
@@ -114,6 +116,13 @@ import Stripe
         paymentContext.paymentCurrency = paymentOptions.currency
         paymentContext.paymentCountry = paymentOptions.country
 
+        if !PluginConfig.paymentOptionsFooter.isEmpty {
+            paymentContext.paymentOptionsViewControllerFooterView = StripePaymentContextFooterView(text: PluginConfig.paymentOptionsFooter, align: .left)
+        }
+        if !PluginConfig.addCardFooter.isEmpty {
+            paymentContext.addCardViewControllerFooterView = StripePaymentContextFooterView(text: PluginConfig.addCardFooter)
+        }
+
         // This dialog collects a payment method from the user. When they close it, you get a context
         // change event with the payment info. NO charge has been created at that point, NO source
         // has been created from the payment method. All that has happened is the user entered

src/ios/StripePaymentsPluginConfig.swift

@@ -10,6 +10,8 @@ public class StripePaymentsPluginConfig {
     public var appleMerchantId: String = ""
     public var companyName: String = ""
     public var maximumKeyRetries: Int = 0
+    public var paymentOptionsFooter: String = ""
+    public var addCardFooter: String = ""
     public var extraHTTPHeaders: [String:String] = [:]
 }