refactor<*>: rewrite all with AvaloniaUI

src/ViewModels/PushTag.cs

@@ -0,0 +1,39 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace SourceGit.ViewModels {
+    public class PushTag : Popup {
+        public Models.Tag Target {
+            get;
+            private set;
+        }
+
+        public List<Models.Remote> Remotes {
+            get => _repo.Remotes;
+        }
+
+        public Models.Remote SelectedRemote {
+            get;
+            set;
+        }
+
+        public PushTag(Repository repo, Models.Tag target) {
+            _repo = repo;
+            Target = target;
+            SelectedRemote = _repo.Remotes[0];
+            View = new Views.PushTag() { DataContext = this };
+        }
+
+        public override Task<bool> Sure() {
+            _repo.SetWatcherEnabled(false);
+            return Task.Run(() => {
+                SetProgressDescription($"Pushing tag '{Target.Name}' to remote '{SelectedRemote.Name}' ...");
+                var succ = new Commands.Push(_repo.FullPath, SelectedRemote.Name, Target.Name, false).Exec();
+                CallUIThread(() => _repo.SetWatcherEnabled(true));
+                return succ;
+            });
+        }
+
+        private Repository _repo = null;
+    }
+}