From c89ee33c5b6c72fab2aee25f6584b83c776dec03 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=BC=98=E9=9F=AC=20=E5=BC=A0?= <hongtao_zhang@outlook.com>
Date: Sun, 15 Nov 2020 20:39:02 +0800
Subject: [PATCH] Use Virtualizing StackPanel instead of GridView to greatly
 reduce the loading resources.

---
 Flow.Launcher/ResultListBox.xaml | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/Flow.Launcher/ResultListBox.xaml b/Flow.Launcher/ResultListBox.xaml
index 072196605..350ef018e 100644
--- a/Flow.Launcher/ResultListBox.xaml
+++ b/Flow.Launcher/ResultListBox.xaml
@@ -16,6 +16,7 @@
          Style="{DynamicResource BaseListboxStyle}" Focusable="False"
          KeyboardNavigation.DirectionalNavigation="Cycle" SelectionMode="Single"
          VirtualizingStackPanel.IsVirtualizing="True" VirtualizingStackPanel.VirtualizationMode="Standard"
+         ScrollViewer.IsDeferredScrollingEnabled="True"
          SelectionChanged="OnSelectionChanged"
          IsSynchronizedWithCurrentItem="True"
          PreviewMouseDown="ListBox_PreviewMouseDown">
@@ -29,26 +30,20 @@
                     </ControlTemplate>
                 </Button.Template>
                 <Button.Content>
-                    <Grid HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Margin="5"
-                          Cursor="Hand" UseLayoutRounding="False">
-                        <Grid.Resources>
+                    <VirtualizingStackPanel Orientation="Horizontal" Margin="5,0,5,0">
+                        <VirtualizingStackPanel.Resources>
                             <converter:HighlightTextConverter x:Key="HighlightTextConverter"/>
                             <converter:OrdinalConverter x:Key="OrdinalConverter" />
                             <converter:OpenResultHotkeyVisibilityConverter x:Key="OpenResultHotkeyVisibilityConverter" />
-                        </Grid.Resources>
-                        <Grid.ColumnDefinitions>
-                            <ColumnDefinition Width="32" />
-                            <ColumnDefinition />
-                            <ColumnDefinition Width="0" />
-                        </Grid.ColumnDefinitions>
+                        </VirtualizingStackPanel.Resources>
                         <Image x:Name="ImageIcon" Width="32" Height="32" HorizontalAlignment="Left"
                                Source="{Binding Image.Value}" />
-                        <Grid Margin="5 0 5 0" Grid.Column="1" HorizontalAlignment="Stretch">
+                        <Grid Margin="5 0 5 0" HorizontalAlignment="Stretch">
                             <Grid.RowDefinitions>
                                 <RowDefinition />
                                 <RowDefinition Height="Auto" x:Name="SubTitleRowDefinition" />
                             </Grid.RowDefinitions>
-                            <StackPanel Visibility="{Binding ShowOpenResultHotkey}">
+                            <VirtualizingStackPanel Visibility="{Binding ShowOpenResultHotkey}">
                                 <TextBlock Margin="0 5 5 0" Style="{DynamicResource ItemSubTitleStyle}" HorizontalAlignment="Right" Opacity="0.8" >
                                     <TextBlock.Visibility>
                                         <Binding RelativeSource="{RelativeSource Mode=FindAncestor, AncestorType=ListBoxItem}" Converter="{StaticResource ResourceKey=OpenResultHotkeyVisibilityConverter}" />
@@ -60,7 +55,7 @@
                                         </MultiBinding>
                                     </TextBlock.Text>
                                 </TextBlock>
-                            </StackPanel>
+                            </VirtualizingStackPanel>
                             <TextBlock Style="{DynamicResource ItemTitleStyle}" DockPanel.Dock="Left"
                                        VerticalAlignment="Center" ToolTip="{Binding ShowTitleToolTip}" x:Name="Title"
                                        Text="{Binding Result.Title}">
@@ -81,7 +76,7 @@
                                 </vm:ResultsViewModel.FormattedText>
                             </TextBlock>
                         </Grid>
-                    </Grid>
+                    </VirtualizingStackPanel>
                 </Button.Content>
             </Button>
             <!-- a result item height is 50 including margin -->