vector-im/element-ios/issues/5114 - Poll creation screen

- added input toolbar poll creation action.
- reordered input toolbar actions as per designs.
- added multiline text field and extracted common components.

RiotSwiftUI/Modules/Room/PollEditForm/PollEditFormModels.swift

@@ -0,0 +1,77 @@
+// File created from SimpleUserProfileExample
+// $ createScreen.sh Room/PollEditForm PollEditForm
+// 
+// Copyright 2021 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
+import SwiftUI
+
+enum PollEditFormStateAction {
+    case viewAction(PollEditFormViewAction)
+}
+
+enum PollEditFormViewAction {
+    case addAnswerOption
+    case deleteAnswerOption(PollEditFormAnswerOption)
+    case cancel
+    case create
+}
+
+enum PollEditFormViewModelResult {
+    case cancel
+    case create(String, [String])
+}
+
+struct PollEditFormQuestion {
+    var text: String {
+        didSet {
+            text = String(text.prefix(maxLength))
+        }
+    }
+    
+    let maxLength: Int
+}
+
+struct PollEditFormAnswerOption: Identifiable, Equatable {
+    let id = UUID()
+
+    var text: String {
+        didSet {
+            text = String(text.prefix(maxLength))
+        }
+    }
+    
+    let maxLength: Int
+}
+
+struct PollEditFormViewState: BindableState {
+    let maxAnswerOptionsCount: Int
+    var bindings: PollEditFormViewStateBindings
+    
+    var confirmationButtonEnabled: Bool {
+        !bindings.question.text.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty &&
+            bindings.answerOptions.filter({ !$0.text.isEmpty }).count >= 2
+    }
+    
+    var addAnswerOptionButtonEnabled: Bool {
+        bindings.answerOptions.count < maxAnswerOptionsCount
+    }
+}
+
+struct PollEditFormViewStateBindings {
+    var question: PollEditFormQuestion
+    var answerOptions: [PollEditFormAnswerOption]
+}