[Android] add another gc.collect for Android to ensure all is collected (#5847)

* add another gc.collect for Android

* move all gc collects to a helper

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla31145.cs

@@ -43,7 +43,7 @@ namespace Xamarin.Forms.Controls.Issues
 			{
 				_resultLabel.Text = $"Page2 IsAlive = {_page2Tracker.IsAlive} ({n++})";
                 await Task.Delay(1000);
-				GC.Collect();
+				GarbageCollectionHelper.Collect();
 			}
 
 			_resultLabel.Text = $"Page2 IsAlive = {_page2Tracker.IsAlive}";

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla31255.cs

@@ -53,7 +53,7 @@ namespace Xamarin.Forms.Controls.Issues
 				((Label)((StackLayout)Content).Children [0]).Text =
 						string.Format ("Page1. But Page2 IsAlive = {0}", _page2Tracker.IsAlive);
 				await Task.Delay (1000);
-				GC.Collect ();
+				GarbageCollectionHelper.Collect();
 			}
 		}
 

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla32206.cs

@@ -78,9 +78,7 @@ namespace Xamarin.Forms.Controls.Issues
 						AutomationId = "GC",
 						Command = new Command(o =>
 						{
-							GC.Collect();
-							GC.WaitForPendingFinalizers();
-							GC.Collect();
+							GarbageCollectionHelper.Collect();
 							Label.Text = "Counter: " + Counter;
 						})
 					},

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla32898.cs

@@ -71,7 +71,7 @@ namespace Xamarin.Forms.Controls.Issues
 			while (_page2Tracker.IsAlive && _tabTracker.IsAlive && watch.ElapsedMilliseconds < Timeout) 
 			{
 				await Task.Delay (1000);
-				GC.Collect ();
+				GarbageCollectionHelper.Collect();
 			}
 
 			watch.Stop();

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla35132.cs

@@ -63,8 +63,7 @@ namespace Xamarin.Forms.Controls.Issues
 			async void Button_Clicked(object sender, EventArgs e)
 			{
 				Debug.WriteLine(">>>>>>>> Invoking Garbage Collector");
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 
 				await Navigation.PushAsync(new BugPage());
 			}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla39489.cs

@@ -93,8 +93,7 @@ namespace Xamarin.Forms.Controls.Issues
 		void GCbutton_Clicked(object sender, EventArgs e)
 		{
 			System.Diagnostics.Debug.WriteLine(">>>>>>>> Running Garbage Collection");
-			GC.Collect();
-			GC.WaitForPendingFinalizers();
+			GarbageCollectionHelper.Collect();
 			System.Diagnostics.Debug.WriteLine($">>>>>>>> GC.GetTotalMemory = {GC.GetTotalMemory(true):n0}");
 		}
 

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla40955.cs

@@ -131,9 +131,7 @@ namespace Xamarin.Forms.Controls.Issues
 			protected override void OnAppearing()
 			{
 				base.OnAppearing();
-				GC.Collect();
-				GC.Collect();
-				GC.Collect();
+				GarbageCollectionHelper.Collect();
 			}
 		}
 	}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla42069.cs

@@ -53,9 +53,7 @@ namespace Xamarin.Forms.Controls.Issues
 			var collectButton = new Button { Text = "Collect" };
 			collectButton.Clicked += (sender, args) =>
 			{
-				GC.Collect();
-				GC.Collect();
-				GC.Collect();
+				GarbageCollectionHelper.Collect();
 			};
 
 			var startPage = new ContentPage

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla42329.cs

@@ -145,9 +145,7 @@ namespace Xamarin.Forms.Controls.Issues
 			protected override void OnAppearing()
 			{
 				base.OnAppearing();
-				GC.Collect();
-				GC.Collect();
-				GC.Collect();
+				GarbageCollectionHelper.Collect();
 			}
 		}
 	}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla43941.cs

@@ -106,8 +106,7 @@ namespace Xamarin.Forms.Controls.Issues
 						AutomationId = "GC",
 						Command = new Command(o =>
 						{
-							GC.Collect();
-							GC.WaitForPendingFinalizers();
+							GarbageCollectionHelper.Collect();
 							Label.Text = "Counter: " + Counter;
 						})
 					},

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla44047.cs

@@ -44,9 +44,7 @@ namespace Xamarin.Forms.Controls.Issues
 	{
 		public Page2()
 		{
-			GC.Collect();
-			GC.WaitForPendingFinalizers();
-			GC.Collect();
+			GarbageCollectionHelper.Collect();
 
 			Title = "Page2";
 			System.Diagnostics.Debug.WriteLine("Constructor");

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla44166.cs

@@ -26,8 +26,7 @@ namespace Xamarin.Forms.Controls.Issues
 			var gcButton = new Button { Text = "GC", AutomationId = "GC" };
 			gcButton.Clicked += (sender, args) =>
 			{
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 
 				if (_44166MDP.Counter > 0)
 				{

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla45722.cs

@@ -98,8 +98,7 @@ namespace Xamarin.Forms.Controls.Issues
 			var collect = new Button() { Text = Collect };
 			collect.Clicked += (sender, args) =>
 			{
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 			};
 
 			Title = "Bugzilla 45722";

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla45722Xaml0.xaml.cs

@@ -45,8 +45,7 @@ namespace Xamarin.Forms.Controls.Issues
 
 			GCButton.Clicked += (sender, args) =>
 			{
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 			};
 
 			MessagingCenter.Subscribe<_45722Label>(this, _45722Label.CountMessage, sender =>

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla45926.cs

@@ -51,8 +51,7 @@ namespace Xamarin.Forms.Controls.Issues
 			};
 
 			doGC.Clicked += (sender, e) => {
-				GC.Collect ();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 				instanceCount.Text = $"Instances: {_45926SecondPage.InstanceCounter.ToString()}";
 				messageCount.Text = $"Messages: {_45926SecondPage.MessageCounter.ToString()}";
 			};

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla51503.cs

@@ -36,8 +36,7 @@ namespace Xamarin.Forms.Controls.Issues
 
 			async void Button_Clicked(object sender, EventArgs e)
 			{
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 
 				await Navigation.PushAsync(new ChildPage());
 			}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla55365.cs

@@ -52,8 +52,7 @@ namespace Xamarin.Forms.Controls.Issues
 
 			var collectButton = new Button { Text = "Garbage", Command = new Command(o =>
 			{
-				GC.Collect();
-				GC.WaitForPendingFinalizers();
+				GarbageCollectionHelper.Collect();
 				_layout.Children.Add(new Label {Text = "Success"});
 			}) };
 			_layout.Children.Add(collectButton);

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla57910.cs

@@ -41,7 +41,7 @@ namespace Xamarin.Forms.Controls.Issues
 			async void Button_Clicked(object sender, EventArgs e)
 			{
 				await Navigation.PushAsync(new ListPage());
-				GC.Collect();
+				GarbageCollectionHelper.Collect();
 			}
 		}
 

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Helpers/GarbageCollectionHelper.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Xamarin.Forms.Controls.Issues
+{
+	public static class GarbageCollectionHelper
+	{
+		public static void Collect()
+		{
+			GC.Collect();
+			GC.WaitForPendingFinalizers();
+			GC.Collect();
+		}
+	}
+}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue1023.cs

@@ -78,9 +78,7 @@ namespace Xamarin.Forms.Controls.Issues
 						AutomationId = "GC",
 						Command = new Command(o =>
 						{
-							GC.Collect();
-							GC.WaitForPendingFinalizers();
-							GC.Collect();
+							GarbageCollectionHelper.Collect();
 							Label.Text = "Counter: " + Counter;
 						})
 					},

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue1024.cs

@@ -78,9 +78,7 @@ namespace Xamarin.Forms.Controls.Issues
 						AutomationId = "GC",
 						Command = new Command(o =>
 						{
-							GC.Collect();
-							GC.WaitForPendingFinalizers();
-							GC.Collect();
+							GarbageCollectionHelper.Collect();
 							Label.Text = "Counter: " + Counter;
 						})
 					},

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue1703.cs

@@ -25,14 +25,14 @@ namespace Xamarin.Forms.Controls.Issues
 
 		static Page CreateWeakReferencedPage()
 		{
-			GC.Collect();
+			GarbageCollectionHelper.Collect();
 			var result = CreatePage();
 			s_pageRefs.Add(new WeakReference(result));
 
 			// Add a second unreferenced page to prove that the problem only exists
 			// when pages are actually navigated to/from
 			s_pageRefs.Add(new WeakReference(CreatePage()));
-			GC.Collect();
+			GarbageCollectionHelper.Collect();
 			return result;
 		}
 

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue1895.cs

@@ -26,9 +26,7 @@ namespace Xamarin.Forms.Controls.Issues
 
 		static Page CreateWeakReferencedPage()
 		{
-			GC.Collect();
-			GC.WaitForPendingFinalizers();
-			GC.Collect();
+			GarbageCollectionHelper.Collect();
 
 			var result = CreatePage();
 			s_pageRefs.Add(new WeakReference(result));

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue2399.cs

@@ -50,8 +50,7 @@ namespace Xamarin.Forms.Controls.Issues
 								Text = "Garbage Collection Things",
 								Command = new Command(() =>
 								{
-									GC.Collect();
-									GC.WaitForPendingFinalizers();
+									GarbageCollectionHelper.Collect();
 									AttachedStateEffects.Clear();
 								}),
 							},
@@ -76,16 +75,14 @@ namespace Xamarin.Forms.Controls.Issues
 			// needed otherwise UWP crashes
 			await Task.Delay(100);
 			await Navigation.PopAsync();
-			GC.Collect();
-			GC.WaitForPendingFinalizers();
+			GarbageCollectionHelper.Collect();
 		}
 
 		void OnAllEventsDetached(object sender, EventArgs args)
 		{
 			AttachedStateEffects.Clear();
 			AttachedStateEffects.AllEventsDetached -= OnAllEventsDetached;
-			GC.Collect();
-			GC.WaitForPendingFinalizers();
+			GarbageCollectionHelper.Collect();
 			AllEffectsHaveDetached.Text = "Success";
 		}
 

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue5555.cs

@@ -59,6 +59,8 @@ namespace Xamarin.Forms.Controls.Issues
 						result.Text = "Click 'Push page' again";
 						return;
 					}
+
+					GarbageCollectionHelper.Collect();
 					result.Text = list[list.Count - 2].IsAlive ? "Failed" : "Success";
 				})
 			};
@@ -76,9 +78,7 @@ namespace Xamarin.Forms.Controls.Issues
 							await Navigation.PushAsync(page);
 							await page.Navigation.PopAsync();
 
-							GC.Collect();
-							GC.WaitForPendingFinalizers();
-							GC.Collect();
+							GarbageCollectionHelper.Collect();
 
 							list.Add(wref);
 							if (list.Count > 1)

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems

@@ -9,6 +9,7 @@
     <Import_RootNamespace>Xamarin.Forms.Controls.Issues</Import_RootNamespace>
   </PropertyGroup>
   <ItemGroup>
+    <Compile Include="$(MSBuildThisFileDirectory)Helpers\GarbageCollectionHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue5555.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla59172.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue4684.xaml.cs" />