Let a tap on the phone's host list mean connect

Choosing a machine raised the connect bar over the bottom of the list: a password box, CONNECT, EDIT, MOVE and DELETE. Five controls in the way of the one thing a tap on a machine's name obviously means. So the gestures split. A tap connects. A long press raises the bar, with all five. The pencil in the phone's header — its only persistent chrome — edits whichever host is chosen, which is the one of the five common enough to be worth a control that is always in the same place. The flag doing it is the desktop's own IsHostPaneOpen rather than a second one. That head made exactly this move when a selection stopped opening its drawer, and the question both are asking is "has somebody asked about this host" — answering it twice is how two heads come to disagree about what a selection means. One tap cannot finish: a host that authenticates with a typed password has nowhere on a list to be given one. That tap raises the bar with the box in it and says so, and a second tap with the box filled in connects. The branch is in the view model rather than in the head, because "can this machine be reached without asking for anything" is the same question the bar's own password box answers, and a copy of it in a view would be a second reading of a binding chain that has one. Two mechanics worth knowing. Avalonia raises Tapped on release whatever the press lasted, so a long press would open the bar and then connect — one touch firing both gestures — which is why HostsScreen tracks the hold and swallows the tap it precedes. And Holding only fires once IsHoldingEnabled is set, so that and the handler are attached together rather than one in markup and one in code. ConnectToRecent now opens the pane rather than selecting the row. On the phone it has to: a selection alone raises nothing now, so going back to a recent machine would land on a screen with nothing to press.
2026-08-05 08:43:33 +02:00
parent 69bc9e270b
commit 746711da9d
8 changed files with 412 additions and 26 deletions
@@ -31,6 +31,23 @@
    Both editors are cards in the list's own row, swapped for the list rather than stacked over it, which is
    what SnippetsScreen does and for the reason written there: a form on top of the list hides what it is
    about. There is no dialog and no editor screen anywhere on this head.
+
+    ── ◆ v4: A TAP CONNECTS, AND THE BAR IS WHAT A LONG PRESS IS FOR. ───────────────────────────────────────
+    Choosing a row used to raise the connect bar over the bottom of the list — a password box, CONNECT, EDIT,
+    MOVE and DELETE, five controls in the way of the one thing a tap on a machine's name means. So the
+    gestures split, and each one now does what it looks like it does:
+
+      · a tap connects, and the bar never appears;
+      · a long press asks about the host: the bar comes up, with all five;
+      · the pencil in the phone's header edits whatever is chosen, which is the one action common enough to
+        be worth a control that is always in the same place.
+
+    The one case a tap cannot finish is a host that authenticates with a typed password, since there is
+    nowhere to type it. That tap raises the bar with the box in it and says so — see
+    VaultViewModel.ConnectToRowAsync, which is where the branch lives and why it is not in this head.
+
+    It is the same move the desktop grid made when a selection stopped opening its drawer, and it reuses that
+    head's flag rather than inventing a second one; see VaultViewModel.IsHostPaneOpen.
  -->

  <!--
@@ -180,9 +197,20 @@
    </StackPanel>

    <!-- ============ the list ============ -->
-    <ListBox Grid.Row="2" Margin="0,6,0,0" IsVisible="{Binding !AnEditorIsOpen}"
+    <!--
+      ◆ Named, because the long press is attached from code-behind: the gesture only fires at all once
+      IsHoldingEnabled is on, and setting the attached property and the handler together is what keeps those
+      two from drifting apart. Tapped stays here, beside the bindings it is about.
+
+      Both are on the list rather than on the row, and the row stays a plain Grid rather than becoming a
+      Button, for the reason FilesScreen writes out: a button as the item template swallows the press before
+      the list sees it, so nothing is ever selected and every control that reads the selection stops working.
+      Both handlers fire after the list has moved its selection, which is what lets them read it.
+    -->
+    <ListBox x:Name="Rows" Grid.Row="2" Margin="0,6,0,0" IsVisible="{Binding !AnEditorIsOpen}"
             ItemsSource="{Binding SidebarRows}"
             SelectedItem="{Binding SelectedSidebarRow}"
+             Tapped="OnRowTapped"
             Background="Transparent" BorderThickness="0">

      <ListBox.Styles>
@@ -548,8 +576,10 @@

    <!-- ============ connect ============ -->
    <!--
-      Raised over the list when a host is chosen, because the desktop's right-hand column has nowhere to go
-      at this width. It names the host: the selection that is obvious on a wide window is not obvious here.
+      ◆ Raised by a long press on a row, not by choosing one. A tap connects — see the v4 note at the top of
+      this file — so what is left in here is everything a tap cannot be: the password for a host that wants
+      one, and EDIT, MOVE and DELETE. It names the host, because the selection that is obvious on a wide
+      window is not obvious under a thumb.

      Gone entirely while an editor is up, rather than merely greyed. The editor replaces the list above it,
      so a bar left in place would be a set of buttons about a host that is no longer on screen — and the
@@ -1,10 +1,109 @@
 using Avalonia.Controls;
+using Avalonia.Input;
 using Avalonia.Markup.Xaml;

+using DodoSSH.Client.Shell.ViewModels;
+
 namespace DodoSSH.Client.Android.Views;

 /// <summary>Design 02 — the host list, and the connect bar that replaces the desktop's right column.</summary>
+/// <remarks>
+/// <para>
+/// ◆ <b>Two gestures on one list, and this file is the whole of the difference between them.</b> A tap on a
+/// host connects to it; a long press asks about it, which is what raises the bar. Why they were split is on
+/// the screen itself; what is here is the mechanics, and there are two of them worth knowing.
+/// </para>
+/// <para>
+/// The handlers are on the <c>ListBox</c> rather than on the row, and the row stays a plain <c>Grid</c>.
+/// A button as the item template swallows the press before the list sees it — <c>FilesScreen</c> writes that
+/// out at length — leaving nothing selected and every control that reads the selection doing nothing. Both
+/// events fire after the list has moved its selection, which is what lets these read it.
+/// </para>
+/// </remarks>
 internal sealed partial class HostsScreen : UserControl
 {
-    public HostsScreen() => AvaloniaXamlLoader.Load(this);
+    /// <summary>
+    /// Whether the press that is about to end was long enough to have meant something else.
+    /// </summary>
+    /// <remarks>
+    /// Avalonia raises <c>Tapped</c> on release whatever the press lasted, so without this a long press
+    /// would open the bar and then connect — the two gestures firing one after the other on one touch, which
+    /// is the one outcome that would make both of them untrustworthy. Set when the hold starts and cleared
+    /// by the tap it suppresses, so it never survives the gesture that set it.
+    /// </remarks>
+    private bool held;
+
+    /// <remarks>
+    /// The long press is attached here rather than in the markup so that it sits beside the property that
+    /// makes it fire at all. <see cref="InputElement.IsHoldingEnabledProperty"/> is set rather than assumed:
+    /// it is the whole of the gesture, and a default that changed would take it away silently — every tap
+    /// would go on working and nothing would ever open the bar again.
+    /// </remarks>
+    public HostsScreen()
+    {
+        AvaloniaXamlLoader.Load(this);
+
+        InputElement.SetIsHoldingEnabled(Rows, true);
+        Rows.Holding += OnRowHeld;
+    }
+
+    /// <summary>
+    /// Connects to the row that was tapped.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// Guarded on the selection being a host rather than on what was under the finger. A tap on a group
+    /// heading moves the list's selection and the view model bounces it straight back to whatever was chosen
+    /// before — see <c>VaultViewModel.SelectedSidebarRow</c> — so reading the selection here answers "a host,
+    /// or nothing" without this file needing to know that rule. The cost of getting it wrong is connecting to
+    /// a machine the user was not pointing at.
+    /// </para>
+    /// <para>
+    /// Fire-and-forget, as the desktop grid's activation is: the command reports its own failures onto the
+    /// status line — an unknown host key, a refused password — and awaiting it here would be an event handler
+    /// returning a task nothing observes.
+    /// </para>
+    /// </remarks>
+    private void OnRowTapped(object? sender, TappedEventArgs e)
+    {
+        if (held)
+        {
+            held = false;
+            return;
+        }
+
+        if (DataContext is VaultViewModel { SelectedHost: { } row } vault)
+        {
+            _ = vault.ConnectToRowCommand.ExecuteAsync(row);
+        }
+    }
+
+    /// <summary>
+    /// Raises the bar about the row that was held.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// On <see cref="HoldingState.Started"/> rather than on completion, so the bar is up while the finger is
+    /// still down. A long press that showed nothing until release would be a gesture with no way to tell it
+    /// had been recognised, and the only feedback available on this list is the thing it does.
+    /// </para>
+    /// <para>
+    /// It goes through <c>OpenHostPaneCommand</c>, which is the desktop's own "ask about this host" — the two
+    /// heads raise different furniture from one flag rather than keeping a selection rule each.
+    /// </para>
+    /// </remarks>
+    private void OnRowHeld(object? sender, HoldingRoutedEventArgs e)
+    {
+        if (e.HoldingState != HoldingState.Started)
+        {
+            return;
+        }
+
+        held = true;
+
+        if (DataContext is VaultViewModel { SelectedHost: { } row } vault)
+        {
+            vault.OpenHostPaneCommand.Execute(row);
+        }
+    }
 }
@@ -72,7 +72,7 @@
        <Border Background="{StaticResource Chrome}" BorderBrush="{StaticResource Border}"
                BorderThickness="0,0,0,1" Padding="14,0" Height="56"
                IsVisible="{Binding !IsMoreSurface}">
-          <Grid ColumnDefinitions="Auto,*,Auto,Auto">
+          <Grid ColumnDefinitions="Auto,*,Auto,Auto,Auto">

            <!--
              Filled rather than outlined since v2. The mark is the one thing on this header that is not a
@@ -100,7 +100,31 @@
              <TextBlock Classes="label" FontSize="9" Text="{Binding SyncLabel}" />
            </StackPanel>

-            <Button Grid.Column="3" Classes="icon" Margin="4,0,0,0" Command="{Binding LockCommand}"
+            <!--
+              ◆ THE PENCIL, and it is here rather than on the row for the reason the whole gesture split
+              happened: choosing a host on this head no longer raises a bar carrying EDIT, because that bar
+              was five controls over the bottom of the list in the way of a tap that means "connect". EDIT is
+              the one of the five common enough to be worth a control that is always in the same place, so it
+              is in the header — the phone's only piece of persistent chrome — and the long press still
+              reaches the other four. See HostsScreen.axaml.
+
+              Two conditions, nested rather than combined, because Avalonia's bindings have no "and" and the
+              two belong to different view models: which screen is showing is the shell's question, and
+              whether there is a host to edit is the vault's. That is the same arrangement the header itself
+              is wrapped in one level up.
+
+              Collapsed rather than disabled when there is nothing chosen. A greyed pencil sitting beside the
+              vault's name on every screen would be a permanent reminder of a control that is only ever about
+              one row.
+            -->
+            <Panel Grid.Column="3" IsVisible="{Binding IsHostsShowing}">
+              <Button Classes="icon" Content="✎" FontSize="15" Margin="4,0,0,0"
+                      IsVisible="{Binding Vault.CanEditSelectedHost}"
+                      Command="{Binding Vault.EditSelectedHostCommand}"
+                      ToolTip.Tip="Edit the selected host" />
+            </Panel>
+
+            <Button Grid.Column="4" Classes="icon" Margin="4,0,0,0" Command="{Binding LockCommand}"
                    ToolTip.Tip="Lock the keychain">
              <TextBlock Text="LOCK" Classes="label" FontSize="8.5"
                         Foreground="{StaticResource TextDim}" />
@@ -1133,9 +1133,17 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
    /// <remarks>
    /// <para>
    /// <b>Two destinations, because a recent row is one of two different things.</b> One that names a
-    /// keychain host goes to that host, selected, on the hosts screen — which is where its connect bar is,
-    /// with whatever authentication the keychain resolves for it and a password box only if it needs one.
-    /// Connecting from here instead would be a third connect path that had to answer all of that again.
+    /// keychain host goes to that host on the hosts screen, with the panel about it opened — the desktop's
+    /// drawer, the phone's connect bar — carrying whatever authentication the keychain resolves for it and a
+    /// password box only if it needs one. Connecting from here instead would be a third connect path that
+    /// had to answer all of that again.
+    /// </para>
+    /// <para>
+    /// ◆ <b>It opens that panel rather than merely selecting the row, and on the phone it has to.</b>
+    /// Choosing a host there no longer raises the bar — a tap on the list connects instead, see
+    /// <c>VaultViewModel.ShowsConnectBar</c> — so arriving with the host selected and nothing else would be
+    /// arriving at a screen with nothing to press. Asking to go back to a machine is exactly the deliberate
+    /// act that flag exists to distinguish from browsing.
    /// </para>
    /// <para>
    /// One that names no item was typed into the manual box, and the log stored exactly what was dialled —
@@ -1163,7 +1171,7 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
            && vault.Hosts.FirstOrDefault(host => host.EntityId == hostId) is { } known
            && vault.IsVaultShown(known.VaultId))
        {
-            vault.SelectedHost = known;
+            vault.OpenHostPaneCommand.Execute(known);
            ShowScreen(ShellScreen.Hosts);
            return;
        }
@@ -1872,6 +1872,7 @@ internal sealed partial class VaultViewModel(
    [ObservableProperty]
    [NotifyPropertyChangedFor(nameof(AnEditorIsOpen))]
    [NotifyPropertyChangedFor(nameof(ShowsConnectBar))]
+    [NotifyPropertyChangedFor(nameof(CanEditSelectedHost))]
    [NotifyPropertyChangedFor(nameof(IsDrawerOpen))]
    [NotifyPropertyChangedFor(nameof(IsShowingHostDetail))]
    [NotifyPropertyChangedFor(nameof(ShowsHostPaneActions))]
@@ -1904,6 +1905,7 @@ internal sealed partial class VaultViewModel(
    [ObservableProperty]
    [NotifyPropertyChangedFor(nameof(AnEditorIsOpen))]
    [NotifyPropertyChangedFor(nameof(ShowsConnectBar))]
+    [NotifyPropertyChangedFor(nameof(CanEditSelectedHost))]
    [NotifyPropertyChangedFor(nameof(IsDrawerOpen))]
    [NotifyPropertyChangedFor(nameof(IsShowingHostDetail))]
    [NotifyPropertyChangedFor(nameof(ShowsHostPaneActions))]
@@ -1965,6 +1967,7 @@ internal sealed partial class VaultViewModel(
    [NotifyPropertyChangedFor(nameof(IsDrawerOpen))]
    [NotifyPropertyChangedFor(nameof(IsShowingHostDetail))]
    [NotifyPropertyChangedFor(nameof(ShowsHostPaneActions))]
+    [NotifyPropertyChangedFor(nameof(ShowsConnectBar))]
    private bool isHostPaneOpen;

    /// <summary>
@@ -2128,6 +2131,7 @@ internal sealed partial class VaultViewModel(
    [ObservableProperty]
    [NotifyPropertyChangedFor(nameof(AnEditorIsOpen))]
    [NotifyPropertyChangedFor(nameof(ShowsConnectBar))]
+    [NotifyPropertyChangedFor(nameof(CanEditSelectedHost))]
    private bool isAddSheetOpen;

    /// <summary>
@@ -2154,6 +2158,7 @@ internal sealed partial class VaultViewModel(
    [ObservableProperty]
    [NotifyPropertyChangedFor(nameof(AnEditorIsOpen))]
    [NotifyPropertyChangedFor(nameof(ShowsConnectBar))]
+    [NotifyPropertyChangedFor(nameof(CanEditSelectedHost))]
    [NotifyPropertyChangedFor(nameof(GroupSheetLabel))]
    private SidebarGroupHeader? groupSheet;

@@ -2176,12 +2181,42 @@ internal sealed partial class VaultViewModel(
    /// Whether the phone's connect bar has anything to be about.
    /// </summary>
    /// <remarks>
-    /// A host is chosen and nothing is covering the list. Both halves are needed and the second is the one
-    /// worth stating: the editor cards replace the list rather than floating over it, so a bar left showing
-    /// underneath would carry CONNECT and EDIT for a host that is no longer on screen — and under the host
-    /// editor, for the very record being typed into.
+    /// <para>
+    /// ◆ <b>Selecting a host no longer raises this bar, and <see cref="IsHostPaneOpen"/> is the difference.</b>
+    /// It used to read <c>SelectedHost is not null</c>, so a tap on any row put a card over the bottom of the
+    /// list carrying a password box, CONNECT, EDIT, MOVE and DELETE — five controls in the way of the one
+    /// thing a tap on a machine's name means, which is connect to it. A tap connects now; a long press asks
+    /// for this. See <see cref="ConnectToRowAsync"/> and <see cref="OpenHostPane"/>.
+    /// </para>
+    /// <para>
+    /// It is the same flag and the same reasoning the desktop's drawer already used, which is why it is that
+    /// flag rather than a second one: the question both heads are asking is "has somebody asked about this
+    /// host", and answering it twice is how two heads come to disagree about what a selection means.
+    /// </para>
+    /// <para>
+    /// The second half stays and is still worth stating: the editor cards replace the list rather than
+    /// floating over it, so a bar left showing underneath would carry CONNECT and EDIT for a host that is no
+    /// longer on screen — and under the host editor, for the very record being typed into.
+    /// </para>
    /// </remarks>
-    internal bool ShowsConnectBar => SelectedHost is not null && !AnEditorIsOpen;
+    internal bool ShowsConnectBar => SelectedHost is not null && IsHostPaneOpen && !AnEditorIsOpen;
+
+    /// <summary>
+    /// Whether the phone's header should be offering the pencil that edits the selected host.
+    /// </summary>
+    /// <remarks>
+    /// The other half of the gesture change above. With the bar no longer raised by choosing a machine, EDIT
+    /// went behind a long press — so the header carries a pencil for the row that <em>is</em> chosen, which
+    /// is the one control a thumb can reach without opening anything. It is hidden rather than disabled while
+    /// an editor is up, because a pencil that opens the form already on screen is a control with nothing to
+    /// do.
+    /// <para>
+    /// It deliberately does not ask which screen is showing. That is the shell's question and this is the
+    /// vault's; the header wraps this in the shell's own <c>IsHostsShowing</c>, which is the arrangement
+    /// PhoneShell already uses everywhere Avalonia's bindings need an "and".
+    /// </para>
+    /// </remarks>
+    internal bool CanEditSelectedHost => SelectedHost is not null && !AnEditorIsOpen;

    /// <summary>
    /// Whether the phone's connect bar is showing its own controls rather than one of the two panels that
@@ -7376,6 +7411,59 @@ internal sealed partial class VaultViewModel(
    [RelayCommand(AllowConcurrentExecutions = true)]
    private Task ConnectAsync() => ConnectToSelectedHostAsync(CancellationToken.None);

+    /// <summary>
+    /// Connects to the host a tap landed on, or raises the phone's bar when it needs a password first.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// <b>The phone's tap, and it lives here rather than in the head because the branch is a product rule
+    /// rather than a gesture.</b> Which gesture means "open this" is the head's business — that is why the
+    /// files screen maps its own tap in code-behind — but <em>whether this machine can be reached without
+    /// asking for anything</em> is the same question the connect bar's own password box answers, and a copy
+    /// of it in a view would be a second reading of a binding chain that already has one.
+    /// </para>
+    /// <para>
+    /// The two outcomes are both "connect": one of them arrives, and the other needs a secret first and so
+    /// puts the bar up with the box in it and says so. What it must never do is quietly connect with no
+    /// password, or open a bar for a host that did not need one — that bar is five controls over the bottom
+    /// of the list, and it is what a tap used to raise for every machine.
+    /// </para>
+    /// <para>
+    /// A successful tap closes the bar. Tapping a second machine while the first one's bar is up would
+    /// otherwise leave the panel behind on the new selection, which is a bar nobody asked for, opened by the
+    /// gesture that exists to avoid opening one.
+    /// </para>
+    /// <para>
+    /// It takes no cancellation token and allows concurrent executions, for the two reasons
+    /// <see cref="ConnectAsync"/> carries at length.
+    /// </para>
+    /// </remarks>
+    [RelayCommand(AllowConcurrentExecutions = true)]
+    private Task ConnectToRowAsync(HostRowViewModel? row)
+    {
+        if (row is null)
+        {
+            return Task.CompletedTask;
+        }
+
+        SelectedHost = row;
+
+        // Read after the assignment, because both are about the row that was just chosen. ConnectPassword
+        // is checked as well as the binding: a bar already up with a password typed into it is exactly the
+        // second tap this should honour rather than answer with the same instruction again.
+        if (SelectedHostAsksForAPassword && ConnectPassword.Length == 0)
+        {
+            IsHostPaneOpen = true;
+            Status = $"{row.Label} asks for a password. Type it below, then CONNECT.";
+
+            return Task.CompletedTask;
+        }
+
+        IsHostPaneOpen = false;
+
+        return ConnectToSelectedHostAsync(CancellationToken.None);
+    }
+
    /// <inheritdoc cref="ConnectAsync" />
    /// <param name="cancellationToken">
    /// Whatever the caller's own lifetime is. The command passes none; the host-key retry passes its own,
@@ -8862,6 +8950,7 @@ internal sealed partial class VaultViewModel(
        OnPropertyChanged(nameof(SelectedHostAsksForAPassword));
        OnPropertyChanged(nameof(SelectedHostAuthenticationNote));
        OnPropertyChanged(nameof(ShowsConnectBar));
+        OnPropertyChanged(nameof(CanEditSelectedHost));

        // Every field the drawer's detail pane draws. They are properties of the vault rather than of the
        // row because two of them need the group chain read and one needs the keychain searched, and none of