Fix: text color of the last event description was incorrect.

Riot/Categories/NSAttributedString+Theme.swift

@@ -0,0 +1,64 @@
+// 
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+
+/// Custom NSAttributedString.Key to specify the theme
+let themeIdentifierAttributeName = NSAttributedString.Key("ThemeIdentifier")
+/// Custom NSAttributedString.Key to specify a theme color by its name
+let themeColorNameAttributeName = NSAttributedString.Key("ThemeColorName")
+
+extension NSAttributedString {
+    /// Fix foreground color attributes if this attributed string contains the `themeIdentifierAttributeName` and `foregroundColorNameAttributeName` attributes
+    /// - Returns: a new attributed string with updated colors
+    @objc func fixForegroundColor() -> NSAttributedString {
+        let activeTheme = ThemeService.shared().theme
+        
+        // Check if a theme is defined for this attributed string
+        var needUpdate = false
+        self.vc_enumerateAttribute(themeIdentifierAttributeName) { (themeIdentifier: String, range: NSRange, _) in
+            needUpdate = themeIdentifier != activeTheme.identifier
+        }
+        
+        guard needUpdate else {
+            return self
+        }
+        
+        // Build a new attributedString with the proper colors if possible
+        let mutableAttributedString = NSMutableAttributedString(attributedString: self)
+        mutableAttributedString.vc_enumerateAttribute(themeColorNameAttributeName) { (colorName: String, range: NSRange, _) in
+            if let color = ThemeColorResolver.getColorByName(colorName) {
+                mutableAttributedString.addAttribute(.foregroundColor, value: color, range: range)
+            }
+        }
+        return mutableAttributedString
+    }
+}
+
+extension NSMutableAttributedString {
+    /// Adds a theme color name attribute
+    /// - Parameters:
+    ///   - colorName: color name
+    ///   - range:range for this attribute
+    @objc func addThemeColorNameAttribute(_ colorName: String, range: NSRange) {
+        self.addAttribute(themeColorNameAttributeName, value: colorName, range: range)
+    }
+    
+    /// Adds a theme identifier attribute
+    @objc func addThemeIdentifierAttribute() {
+        self.addAttribute(themeIdentifierAttributeName, value: ThemeService.shared().theme.identifier, range: .init(location: 0, length: length))
+    }
+}