CA-368812: Prevent host reset when moving between wizard pages using SelectMultipleVMDestinationPage

Multiple changes:

1. Remove `SetDefaultTarget(ChosenItem);` from `PageLeaveCore`. This was clearing the value every time the page was left.
2. Add event `m_dataGridView_CellValueChanged`. Inside the event, we keep track of which target host/pool was selected
3. Add a check that resets the value set in `m_dataGridView_CellValueChanged` in case the chosen pool is changed.

Signed-off-by: Danilo Del Busso <Danilo.Del.Busso@citrix.com>

XenAdmin/Wizards/GenericPages/SelectMultipleVMDestinationPage.Designer.cs

@@ -103,6 +103,7 @@
             this.m_dataGridView.Name = "m_dataGridView";
             this.m_dataGridView.RowHeadersVisible = false;
             this.m_dataGridView.CellClick += new System.Windows.Forms.DataGridViewCellEventHandler(this.m_dataGridView_CellClick);
+            this.m_dataGridView.CellValueChanged += new System.Windows.Forms.DataGridViewCellEventHandler(this.m_dataGridView_CellValueChanged);
             this.m_dataGridView.CurrentCellDirtyStateChanged += new System.EventHandler(this.m_dataGridView_CurrentCellDirtyStateChanged);
             // 
             // m_colVmName

XenAdmin/Wizards/GenericPages/SelectMultipleVMDestinationPage.cs

@@ -205,7 +205,6 @@ namespace XenAdmin.Wizards.GenericPages
             }
 
             UnregisterHandlers();
-            SetDefaultTarget(ChosenItem);
             ClearComboBox();
         }
 
@@ -612,6 +611,12 @@ namespace XenAdmin.Wizards.GenericPages
             if (updatingHomeServerList)
                 return;
 
+            // when selecting a new destination pool, reset the target host selection
+            if (ChosenItem != null && !ChosenItem.Equals(m_comboBoxConnection.SelectedItem))
+            {
+                SetDefaultTarget(null);
+            }
+
             //If the item is delay loading and them item is disabled, null the selection made 
             //and clear the table containing server data
             IEnableableXenObjectComboBoxItem item = m_comboBoxConnection.SelectedItem as IEnableableXenObjectComboBoxItem;
@@ -675,6 +680,20 @@ namespace XenAdmin.Wizards.GenericPages
                 SetButtonNextEnabled(true);
 		}
 
+        private void m_dataGridView_CellValueChanged(object sender, DataGridViewCellEventArgs e)
+        {
+            if (e.RowIndex < 0 || e.ColumnIndex < 0)
+            {
+                return;
+            }
+
+            var cell = m_dataGridView.Rows[e.RowIndex].Cells[e.ColumnIndex];
+            if (cell.Value is IEnableableXenObjectComboBoxItem value)
+            {
+                SetDefaultTarget(value.Item);
+            }
+        }
+
         #endregion
 
         private void UnregisterHandlers()

XenAdmin/Wizards/GenericPages/SelectMultipleVMDestinationPage.resx

@@ -151,7 +151,7 @@
     <value>m_labelIntro</value>
   </data>
   <data name="&gt;&gt;m_labelIntro.Type" xml:space="preserve">
-    <value>XenAdmin.Controls.Common.AutoHeightLabel, XenCenterMain, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
+    <value>XenAdmin.Controls.Common.AutoHeightLabel, [XenCenter_No_Space]Main, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
   </data>
   <data name="&gt;&gt;m_labelIntro.Parent" xml:space="preserve">
     <value>tableLayoutPanel1</value>
@@ -205,7 +205,7 @@
     <value>m_comboBoxConnection</value>
   </data>
   <data name="&gt;&gt;m_comboBoxConnection.Type" xml:space="preserve">
-    <value>XenAdmin.Controls.EnableableComboBox, XenCenterMain, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
+    <value>XenAdmin.Controls.EnableableComboBox, [XenCenter_No_Space]Main, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
   </data>
   <data name="&gt;&gt;m_comboBoxConnection.Parent" xml:space="preserve">
     <value>tableLayoutPanel1</value>
@@ -427,12 +427,12 @@
     <value>m_colTarget</value>
   </data>
   <data name="&gt;&gt;m_colTarget.Type" xml:space="preserve">
-    <value>XenAdmin.Controls.EnableableComboBoxColumn, XenCenterMain, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
+    <value>XenAdmin.Controls.EnableableComboBoxColumn, [XenCenter_No_Space]Main, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
   </data>
   <data name="&gt;&gt;$this.Name" xml:space="preserve">
     <value>SelectMultipleVMDestinationPage</value>
   </data>
   <data name="&gt;&gt;$this.Type" xml:space="preserve">
-    <value>XenAdmin.Controls.XenTabPage, XenCenterMain, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
+    <value>XenAdmin.Controls.XenTabPage, [XenCenter_No_Space]Main, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null</value>
   </data>
 </root>