Doubleclick items to replace them

osu!BackgroundChanger/MainForm.Designer.cs

@@ -280,6 +280,7 @@
             this.listView1.UseCompatibleStateImageBehavior = false;
             this.listView1.View = System.Windows.Forms.View.List;
             this.listView1.SelectedIndexChanged += new System.EventHandler(this.listView1_SelectedIndexChanged);
+            this.listView1.MouseDoubleClick += new System.Windows.Forms.MouseEventHandler(this.listView1_MouseDoubleClick);
             // 
             // pictureBox1
             // 

osu!BackgroundChanger/MainForm.cs

@@ -113,6 +113,8 @@ namespace osu_BackgroundChanger
 
         private void ReplaceImage()
         {
+            if (listView1.SelectedItems.Count == 0) return;
+
             var ofd = new OpenFileDialog();
             ofd.Filter = "Jpeg files|*.jpg;*.jpeg";
             ofd.Title = "Replace";
@@ -198,6 +200,7 @@ namespace osu_BackgroundChanger
         private void aboutToolStripMenuItem_Click(object sender, EventArgs e) => ShowAbout();
         private void whatIsThisToolStripMenuItem_Click(object sender, EventArgs e) => ShowHelp();
 
+        private void listView1_MouseDoubleClick(object sender, MouseEventArgs e) => ReplaceImage();
         private void listView1_SelectedIndexChanged(object sender, EventArgs e)
         {
             UpdateImagePreview();