fix(worterbuch): blank screen when opening canvas

WorterBuch/FieldEditorView.swift

@@ -29,23 +29,39 @@ struct FieldEditorView: View {
     let fieldType: FieldType
 
     @State private var isRecognizing = false
+    @State private var viewAppeared = false
 
     var body: some View {
         NavigationView {
             VStack(spacing: 0) {
                 // Handwriting canvas
-                HandwritingCanvasView(
-                    drawing: $drawing,
-                    onDrawingChanged: { newDrawing in
-                        recognizeHandwriting(newDrawing)
-                    },
-                    isEditable: true
-                )
-                .frame(maxWidth: .infinity)
-                .frame(height: 400)
-                .background(Color(.systemGray6))
-                .cornerRadius(12)
-                .padding()
+                if viewAppeared {
+                    HandwritingCanvasView(
+                        drawing: $drawing,
+                        onDrawingChanged: { newDrawing in
+                            recognizeHandwriting(newDrawing)
+                        },
+                        isEditable: true
+                    )
+                    .frame(maxWidth: .infinity)
+                    .frame(height: 400)
+                    .background(Color(.systemGray6))
+                    .cornerRadius(12)
+                    .padding()
+                } else {
+                    // Placeholder while loading
+                    Rectangle()
+                        .fill(Color(.systemGray6))
+                        .frame(height: 400)
+                        .cornerRadius(12)
+                        .padding()
+                        .onAppear {
+                            // Show canvas after a brief delay to ensure window is ready
+                            DispatchQueue.main.asyncAfter(deadline: .now() + 0.15) {
+                                viewAppeared = true
+                            }
+                        }
+                }
 
                 // Transcribed text section
                 VStack(alignment: .leading, spacing: 8) {

WorterBuch/HandwritingCanvasView.swift

@@ -22,15 +22,8 @@ struct HandwritingCanvasView: UIViewRepresentable {
         canvasView.backgroundColor = .clear
         canvasView.isUserInteractionEnabled = isEditable
 
-        // Use the shared tool picker and show it after a delay
-        DispatchQueue.main.async {
-            if isEditable, let window = canvasView.window {
-                let toolPicker = PKToolPicker.shared(for: window)
-                toolPicker?.setVisible(true, forFirstResponder: canvasView)
-                toolPicker?.addObserver(canvasView)
-                canvasView.becomeFirstResponder()
-            }
-        }
+        // Store canvas in coordinator for later access
+        context.coordinator.canvasView = canvasView
 
         return canvasView
     }
@@ -41,15 +34,9 @@ struct HandwritingCanvasView: UIViewRepresentable {
         }
         canvasView.isUserInteractionEnabled = isEditable
 
-        // Ensure tool picker is visible when editable
-        if isEditable {
-            DispatchQueue.main.async {
-                if let window = canvasView.window {
-                    let toolPicker = PKToolPicker.shared(for: window)
-                    toolPicker?.setVisible(true, forFirstResponder: canvasView)
-                    canvasView.becomeFirstResponder()
-                }
-            }
+        // Set up tool picker when window becomes available
+        if isEditable && canvasView.window != nil && !context.coordinator.toolPickerSetup {
+            context.coordinator.setupToolPicker()
         }
     }
 
@@ -60,10 +47,32 @@ struct HandwritingCanvasView: UIViewRepresentable {
     class Coordinator: NSObject, PKCanvasViewDelegate {
         var drawing: Binding<PKDrawing>
         var onDrawingChanged: ((PKDrawing) -> Void)?
+        var canvasView: PKCanvasView?
+        var toolPicker: PKToolPicker?
+        var toolPickerSetup = false
 
         init(drawing: Binding<PKDrawing>, onDrawingChanged: ((PKDrawing) -> Void)?) {
             self.drawing = drawing
             self.onDrawingChanged = onDrawingChanged
+            super.init()
+            // Create a dedicated tool picker instance
+            self.toolPicker = PKToolPicker()
+        }
+
+        func setupToolPicker() {
+            guard let canvasView = canvasView,
+                  let toolPicker = toolPicker,
+                  canvasView.window != nil,
+                  !toolPickerSetup else {
+                return
+            }
+
+            toolPickerSetup = true
+
+            // Set visible and add observer immediately
+            toolPicker.setVisible(true, forFirstResponder: canvasView)
+            toolPicker.addObserver(canvasView)
+            canvasView.becomeFirstResponder()
         }
 
         func canvasViewDrawingDidChange(_ canvasView: PKCanvasView) {

WorterBuch/VocabularyGridView.swift

@@ -9,6 +9,12 @@ import SwiftUI
 import PencilKit
 import CoreData
 
+struct FieldSelection: Identifiable {
+    let id = UUID()
+    let entry: VocabularyEntry
+    let fieldType: FieldType
+}
+
 struct VocabularyGridView: View {
     @Environment(\.managedObjectContext) private var viewContext
     @FetchRequest(
@@ -18,13 +24,7 @@ struct VocabularyGridView: View {
     private var entries: FetchedResults<VocabularyEntry>
 
     @State private var searchText = ""
-    @State private var selectedEntry: VocabularyEntry?
-    @State private var selectedFieldType: FieldType?
-    @State private var showingFieldEditor = false
-
-    // Temporary bindings for editing
-    @State private var editingDrawing: PKDrawing = PKDrawing()
-    @State private var editingText: String = ""
+    @State private var fieldSelection: FieldSelection?
 
     var filteredEntries: [VocabularyEntry] {
         if searchText.isEmpty {
@@ -111,16 +111,14 @@ struct VocabularyGridView: View {
                     }
                 }
             }
-            .sheet(isPresented: $showingFieldEditor) {
-                if let entry = selectedEntry, let fieldType = selectedFieldType {
-                    FieldEditorView(
-                        drawing: bindingForDrawing(entry: entry, fieldType: fieldType),
-                        text: bindingForText(entry: entry, fieldType: fieldType),
-                        fieldType: fieldType
-                    )
-                    .onDisappear {
-                        saveContext()
-                    }
+            .sheet(item: $fieldSelection) { selection in
+                FieldEditorView(
+                    drawing: bindingForDrawing(entry: selection.entry, fieldType: selection.fieldType),
+                    text: bindingForText(entry: selection.entry, fieldType: selection.fieldType),
+                    fieldType: selection.fieldType
+                )
+                .onDisappear {
+                    saveContext()
                 }
             }
         }
@@ -128,9 +126,7 @@ struct VocabularyGridView: View {
     }
 
     private func openFieldEditor(for entry: VocabularyEntry, fieldType: FieldType) {
-        selectedEntry = entry
-        selectedFieldType = fieldType
-        showingFieldEditor = true
+        fieldSelection = FieldSelection(entry: entry, fieldType: fieldType)
     }
 
     private func bindingForDrawing(entry: VocabularyEntry, fieldType: FieldType) -> Binding<PKDrawing> {