From b3b014f84ebc779c5b9fbb97bb7fe7d451c71cbf Mon Sep 17 00:00:00 2001
From: leo <longshuang@msn.cn>
Date: Thu, 26 Nov 2020 13:18:03 +0800
Subject: [PATCH] feature<Histories>: add usage guide for histories panel.

---
 src/UI/Histories.xaml    | 17 +++++++++++++++--
 src/UI/Histories.xaml.cs |  9 ++++++---
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/UI/Histories.xaml b/src/UI/Histories.xaml
index cf6fd4af..e37e4bd1 100644
--- a/src/UI/Histories.xaml
+++ b/src/UI/Histories.xaml
@@ -172,13 +172,26 @@
             <local:TwoCommitsDiff x:Name="twoCommitDiff" Visibility="Collapsed"/>
 
             <!-- Mask for select multi rows in commit list -->
-            <Border x:Name="mask4MultiSelection" Background="{StaticResource Brush.BG1}">
-                <StackPanel Orientation="Vertical" VerticalAlignment="Center" Opacity=".2">
+            <Border x:Name="selectionCounter" Background="{StaticResource Brush.BG1}" Visibility="Collapsed">
+                <StackPanel Orientation="Vertical" VerticalAlignment="Center" Opacity=".25">
                     <Path Width="160" Height="160" Style="{StaticResource Style.Icon}" Data="{StaticResource Icon.Git}"/>
                     <Label x:Name="txtTotalSelected" Content="SELECT TO VIEW DETAIL" FontFamily="Consolas" Margin="0,16,0,0" FontSize="24" FontWeight="UltraBold" HorizontalAlignment="Center"/>
                 </StackPanel>
             </Border>
 
+            <!-- Usage Page -->
+            <Border x:Name="welcome" Background="{StaticResource Brush.BG1}">
+                <StackPanel Orientation="Vertical" VerticalAlignment="Center" Opacity=".25">
+                    <Path Width="120" Height="120" Style="{StaticResource Style.Icon}" Data="{StaticResource Icon.Git}"/>
+                    <Label Content="HISTORIES GUIDE" FontFamily="Consolas" FontWeight="ExtraBold" FontSize="24" HorizontalAlignment="Center" Margin="0,32,0,16"/>
+                    <StackPanel Orientation="Vertical" HorizontalAlignment="Center" TextElement.FontFamily="Consolas" TextElement.FontSize="16" Margin="16,0,0,0">
+                        <Label Margin="0" Padding="1" Content="1. Select 1 commit to view detail info"/>
+                        <Label Margin="0" Padding="1" Content="2. Select 2 commits to show differences"/>
+                        <Label Margin="0" Padding="1" Content="3. Select more than 2 commits to count"/>
+                    </StackPanel>
+                </StackPanel>
+            </Border>
+
             <!-- SWITCH LAYOUT -->
             <ToggleButton
                 HorizontalAlignment="Right"
diff --git a/src/UI/Histories.xaml.cs b/src/UI/Histories.xaml.cs
index 9995539c..696dc91c 100644
--- a/src/UI/Histories.xaml.cs
+++ b/src/UI/Histories.xaml.cs
@@ -269,19 +269,22 @@ namespace SourceGit.UI {
         }
 
         private void CommitSelectChanged(object sender, SelectionChangedEventArgs e) {
-            mask4MultiSelection.Visibility = Visibility.Collapsed;
+            selectionCounter.Visibility = Visibility.Collapsed;
             commitViewer.Visibility = Visibility.Collapsed;
             twoCommitDiff.Visibility = Visibility.Collapsed;
+            welcome.Visibility = Visibility.Collapsed;
 
             var selected = commitList.SelectedItems;
-            if (selected.Count == 1) {
+            if (selected.Count == 0) {
+                welcome.Visibility = Visibility.Visible;
+            } else if (selected.Count == 1) {
                 commitViewer.Visibility = Visibility.Visible;
                 commitViewer.SetData(Repo, selected[0] as Git.Commit);
             } else if (selected.Count == 2) {
                 twoCommitDiff.Visibility = Visibility.Visible;
                 twoCommitDiff.SetData(Repo, (selected[0] as Git.Commit).ShortSHA, (selected[1] as Git.Commit).ShortSHA);
             } else {
-                mask4MultiSelection.Visibility = Visibility.Visible;
+                selectionCounter.Visibility = Visibility.Visible;
                 txtTotalSelected.Content = $"SELECTED {selected.Count} COMMITS";
             }
         }