add full screen view for task description

src/ViewModel/Pages/taskViewModel.ts

@@ -58,6 +58,8 @@ export default class TaskViewModel extends Context {
     selectedVersionId: React.State<string> = new React.State("");
     versionIds: React.ListState<string> = new React.ListState();
 
+    isPresentingFullScreenDescription: React.State<boolean> = new React.State(false);
+
     // methods
     dragStart = (event: DragEvent): void => {
         ViewController.allowDrag(event);
@@ -96,6 +98,14 @@ export default class TaskViewModel extends Context {
         this.save();
     };
 
+    openFullscreenDecription = (): void => {
+	this.isPresentingFullScreenDescription.value = true;
+    }
+
+    closeFullscreenDecription = (): void => {
+	this.isPresentingFullScreenDescription.value = false;
+    }
+
     updateIndex = (): void => {
         const index: number =
             this.containingViewModel.taskIndexManager.getIndex(this);