Merge from master.

FunctionZero.Maui.Controls/BackingStore/BindableBackingStore.cs

@@ -0,0 +1,69 @@
+using FunctionZero.ExpressionParserZero.BackingStore;
+using FunctionZero.ExpressionParserZero.Operands;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace FunctionZero.Maui.BackingStore
+{
+    public class BindableBackingStore : IBackingStore
+    {
+        private static char[] _dot = new[] { '.' };
+
+        public BindableBackingStore(object host)
+        {
+            Host = host;
+        }
+
+        public object Host { get; }
+
+        public (OperandType type, object value) GetValue(string qualifiedName)
+        {
+            var hostInfo = GetPropertyInfo(Host, qualifiedName);
+            var value = hostInfo.info.GetValue(hostInfo.host);
+
+            if (BackingStoreHelpers.OperandTypeLookup.TryGetValue(hostInfo.info.PropertyType, out var theOperandType))
+                return (theOperandType, value);
+
+            if (value == null)
+                return (OperandType.Null, null);
+
+            return (OperandType.Object, value);
+        }
+
+        public void SetValue(string qualifiedName, object value)
+        {
+            var hostInfo = GetPropertyInfo(Host, qualifiedName);
+
+            //if(hostInfo.info.CanWrite)
+            {
+                hostInfo.info.SetValue(hostInfo.host, value);
+            }
+        }
+
+        protected (object host, PropertyInfo info) GetPropertyInfo(object host, string qualifiedName)
+        {
+            var bits = qualifiedName.Split(_dot);
+
+            PropertyInfo pi = null;
+            object nextHost = host;
+            foreach (var bit in bits)
+            {
+                host = nextHost;
+
+                // Get info for the property
+                pi = host.GetType().GetProperty(bit, BindingFlags.Public | BindingFlags.Instance);
+                if (pi == null || pi.CanRead == false)
+                    return (null, null);
+
+
+                nextHost = pi.GetValue(host);
+            }
+            return (host, pi);
+        }
+
+    }
+}

FunctionZero.Maui.Controls/Controls/MultiView/MultiViewAnimation.cs

@@ -44,24 +44,6 @@ private static void ToChanged(BindableObject bindable, object oldValue, object n
 
         #endregion
 
-        //#region DurationProperty
-
-        //public static readonly BindableProperty DurationProperty = BindableProperty.Create(nameof(Duration), typeof(double), typeof(MultiViewAnimation), 0.0, BindingMode.OneWay, null, DurationChanged);
-
-        //public double Duration
-        //{
-        //    get { return (double)GetValue(DurationProperty); }
-        //    set { SetValue(DurationProperty, value); }
-        //}
-
-        //private static void DurationChanged(BindableObject bindable, object oldValue, object newValue)
-        //{
-        //    var self = (MultiViewAnimation)bindable;
-
-        //}
-
-        //#endregion
-
         #region EasingFuncProperty
 
         public static readonly BindableProperty EasingFuncProperty = BindableProperty.Create(nameof(EasingFunc), typeof(Easing), typeof(MultiViewAnimation), Easing.Linear, BindingMode.OneWay, null, EasingFuncChanged);
@@ -97,6 +79,24 @@ private static void ExpressionChanged(BindableObject bindable, object oldValue,
 
         #endregion
 
+        #region StartingExpressionProperty
+
+        public static readonly BindableProperty StartingExpressionProperty = BindableProperty.Create(nameof(StartingExpression), typeof(string), typeof(MultiViewAnimation), string.Empty, BindingMode.OneWay, null, StartingExpressionChanged);
+
+        public string StartingExpression
+        {
+            get { return (string)GetValue(StartingExpressionProperty); }
+            set { SetValue(StartingExpressionProperty, value); }
+        }
+
+        private static void StartingExpressionChanged(BindableObject bindable, object oldValue, object newValue)
+        {
+            var self = (MultiViewAnimation)bindable;
+        }
+
+        #endregion
+
+
         #region FinishedExpressionProperty
 
         public static readonly BindableProperty FinishedExpressionProperty = BindableProperty.Create(nameof(FinishedExpression), typeof(string), typeof(MultiViewAnimation), string.Empty, BindingMode.OneWay, null, FinishedExpressionChanged);

FunctionZero.Maui.Controls/Controls/MultiView/MultiViewZero.cs

@@ -1,4 +1,5 @@
 using FunctionZero.ExpressionParserZero.BackingStore;
+using FunctionZero.ExpressionParserZero.Evaluator;
 using FunctionZero.Maui.zBind.z;
 using Microsoft.Maui.Layouts;
 using System.Diagnostics;
@@ -10,14 +11,12 @@ public class MultiViewZero : Layout
     {
         private readonly PocoBackingStore _backingStore;
 
-        private static int _instanceCount = 0;
         public MultiViewZero()
         {
             InAnimations = new List<MultiViewAnimation>();
             OutAnimations = new List<MultiViewAnimation>();
 
             _backingStore = new PocoBackingStore(this);
-            _instanceCount++;
 
         }
         protected override ILayoutManager CreateLayoutManager()
@@ -130,6 +129,8 @@ private static void TopViewNameChanged(BindableObject bindable, object oldValue,
 
         private void SetTopView(View theChildView)
         {
+            (PreviousView as View)?.AbortAnimation("PreviousAnimation");
+            (CurrentView as View)?.AbortAnimation("CurrentAnimation");
 
             PreviousView = CurrentView;
             CurrentView = theChildView;
@@ -142,57 +143,66 @@ private void SetTopView(View theChildView)
                 // Workaround for https://github.com/dotnet/maui/issues/18433
                 if (previousViewAsView.IsLoaded)
                 {
-                    previousViewAsView.AbortAnimation("PreviousAnimation"+ _instanceCount.ToString());
+                    previousViewAsView.AbortAnimation("PreviousAnimation");
 
                     var a = new Animation();
 
                     foreach (var anim in OutAnimations)
                     {
                         // TODO: Horribly inefficient!
                         var compiledExpression = ep.Parse(anim.Expression);
+                        var compiledStartingExpression = ep.Parse(anim.StartingExpression);
                         var compiledFinishedExpression = ep.Parse(anim.FinishedExpression);
 
-                        a.Add(0, 1, new Animation(val => { value = val; compiledExpression.Evaluate(_backingStore); }, anim.From, anim.To, anim.EasingFunc, () => compiledFinishedExpression.Evaluate(_backingStore)));
+                        TryEvaluate(compiledStartingExpression, _backingStore);
+
+                        a.Add(0, 1, new Animation(val => { value = val; TryEvaluate(compiledExpression, _backingStore); }, anim.From, anim.To, anim.EasingFunc, () => TryEvaluate(compiledFinishedExpression,_backingStore)));
                     }
-                    a.Commit(this, "PreviousAnimation" + _instanceCount.ToString(), 16, OutDuration, null, null, () => false);
+                    a.Commit(this, "PreviousAnimation", 16, OutDuration, null, null, () => false);
                 }
                 else
                 {
                     foreach (var anim in OutAnimations)
                     {
+                        // TODO: Call compiledStartingExpression, compiledFinishedExpression
                         // TODO: Horribly inefficient!
                         var compiledExpression = ep.Parse(anim.Expression);
                         value = 1.0;
-                        compiledExpression.Evaluate(_backingStore);
+                        TryEvaluate(compiledExpression, _backingStore);
                     }
                 }
             }
             if (CurrentView is View currentViewAsView)
             {
                 if (currentViewAsView.IsLoaded)
                 {
-                    currentViewAsView.AbortAnimation("CurrentAnimation" + _instanceCount.ToString());
+                    currentViewAsView.AbortAnimation("CurrentAnimation");
 
                     var a = new Animation();
 
                     foreach (var anim in InAnimations)
                     {
                         // TODO: Horribly inefficient!
                         var compiledExpression = ep.Parse(anim.Expression);
+                        var compiledStartingExpression = ep.Parse(anim.StartingExpression);
                         var compiledFinishedExpression = ep.Parse(anim.FinishedExpression);
-                        a.Add(0, 1, new Animation(val => { value = val; compiledExpression.Evaluate(_backingStore); }, anim.From, anim.To, anim.EasingFunc,()=> compiledFinishedExpression.Evaluate(_backingStore)));
+
+                        TryEvaluate(compiledStartingExpression,_backingStore);
+
+                        a.Add(0, 1, new Animation(val => { value = val; TryEvaluate(compiledExpression,_backingStore); }, anim.From, anim.To, anim.EasingFunc, () => TryEvaluate(compiledFinishedExpression,_backingStore)));
                     }
-                    a.Commit(this, "CurrentAnimation" + _instanceCount.ToString(), 16, InDuration, null, null, () => false);
+                    a.Commit(this, "CurrentAnimation", 16, InDuration, null, null, () => false);
 
                 }
                 else
                 {
+                    // TODO: Call compiledStartingExpression, compiledFinishedExpression
                     foreach (var anim in InAnimations)
                     {
                         // TODO: Horribly inefficient!
                         var compiledExpression = ep.Parse(anim.Expression);
                         value = 1.0;
-                        compiledExpression.Evaluate(_backingStore);
+                        TryEvaluate(compiledExpression,_backingStore);
                     }
                 }
             }
@@ -201,6 +211,20 @@ private void SetTopView(View theChildView)
             (this as IView).InvalidateArrange();
         }
 
+        private bool TryEvaluate(ExpressionTree compiledExpression, PocoBackingStore backingStore)
+        {
+            try
+            {
+                compiledExpression.Evaluate(_backingStore);
+                return true;
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine(ex.Message);
+                return false;
+            }
+        }
+
         #endregion
 
         public double value { get; protected set; }

FunctionZero.Maui.Controls/FunctionZero.Maui.Controls.csproj

@@ -25,11 +25,11 @@
 		<PackageProjectUrl>https://github.com/Keflon/FunctionZero.Maui.Controls</PackageProjectUrl>
 		<RepositoryUrl>https://github.com/Keflon/FunctionZero.Maui.Controls</RepositoryUrl>
 		<PackageTags>MAUI; ListView; ListViewZero; TreeView; TreeViewZero; MaskView; iOS; WinUI; Windows; Android; Control </PackageTags>
-		<PackageReleaseNotes>Added a preview of a MultiView control.</PackageReleaseNotes>
+		<PackageReleaseNotes>Added StartingExpressionProperty to MultiViewAnimation used by the preview MultiView control.</PackageReleaseNotes>
 		<PackageLicenseFile>License.md</PackageLicenseFile>
-		<IncludeSymbols>True</IncludeSymbols>
+		<IncludeSymbols>False</IncludeSymbols>
 		<SymbolPackageFormat>snupkg</SymbolPackageFormat>
-		<Version>8.0.0.2-pre8</Version>
+		<Version>8.0.0.2-pre7</Version>
 		<PackageIcon>F0 gravatar.png</PackageIcon>
 	</PropertyGroup>
 

SampleApp/Mvvm/Pages/MultiView/MultiViewModalPage.xaml

@@ -43,13 +43,14 @@
 
 
 
-        <cz:MultiViewZero Grid.Row="1" TopViewName="{Binding TopViewName}" InDuration="666" OutDuration="666" BackgroundColor="Yellow">
+        <cz:MultiViewZero Grid.Row="1" TopViewName="{Binding TopViewName}" InDuration="6666" OutDuration="6666" BackgroundColor="Yellow">
 <!--TODO: Add ItemControlTemplate-->
             <cz:MultiViewZero.InAnimations>
                 <cz:MultiViewAnimation
                     From="0"
                     To="1"
                     EasingFunc="{x:Static Easing.BounceOut}"
+                    StartingExpression="CurrentView.Scale=value"
                     Expression="CurrentView.Scale=value"
                     FinishedExpression=""
                     >