Added diagnostic popup to devtools.

Perspex.Base/Diagnostics/PerspexObjectExtensions.cs

@@ -0,0 +1,35 @@
+// --------------------------------------------------------------------
+// <copyright file="PerspexObjectExtensions.cs" company="Steven Kirk">
+// Copyright 2014 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Diagnostics
+{
+    public static class PerspexObjectExtensions
+    {
+        public static PerspexPropertyValue GetDiagnostic(this PerspexObject o, PerspexProperty property)
+        {
+            var set = o.GetSetValues();
+
+            PriorityValue value;
+
+            if (set.TryGetValue(property, out value))
+            {
+                return new PerspexPropertyValue(
+                    property,
+                    value.Value,
+                    (BindingPriority)value.ValuePriority,
+                    value.GetDiagnostic());
+            }
+            else
+            {
+                return new PerspexPropertyValue(
+                    property, 
+                    o.GetValue(property),
+                    BindingPriority.Unset,
+                    "Unset");
+            }
+        }
+    }
+}

Perspex.Base/Diagnostics/PerspexPropertyValue.cs

@@ -11,17 +11,21 @@ namespace Perspex.Diagnostics
         public PerspexPropertyValue(
             PerspexProperty property, 
             object value,
-            BindingPriority priority)
+            BindingPriority priority,
+            string diagnostic)
         {
             this.Property = property;
             this.Value = value;
             this.Priority = priority;
+            this.Diagnostic = diagnostic;
         }
 
-        public PerspexProperty Property { get; private set; }
+        public PerspexProperty Property { get; }
 
-        public object Value { get; private set; }
+        public object Value { get; }
 
-        public BindingPriority Priority { get; private set; }
+        public BindingPriority Priority { get; }
+
+        public string Diagnostic { get; }
     }
 }

Perspex.Base/Perspex.Base.csproj

@@ -37,6 +37,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Binding.cs" />
+    <Compile Include="Diagnostics\PerspexObjectExtensions.cs" />
     <Compile Include="PriorityBindingEntry.cs" />
     <Compile Include="Collections\IPerspexList.cs" />
     <Compile Include="Collections\PerspexReadOnlyListView.cs" />

Perspex.Base/PerspexObject.cs

@@ -409,35 +409,6 @@ namespace Perspex
             return (T)this.GetValue((PerspexProperty)property);
         }
 
-        /// <summary>
-        /// Gets the value of of all properties that are registered on this object.
-        /// </summary>
-        /// <returns>
-        /// A collection of <see cref="PerspexPropertyValue"/> objects.
-        /// </returns>
-        public IEnumerable<PerspexPropertyValue> GetAllValues()
-        {
-            foreach (PerspexProperty property in this.GetRegisteredProperties())
-            {
-                PriorityValue value;
-
-                if (this.values.TryGetValue(property, out value))
-                {
-                    yield return new PerspexPropertyValue(
-                        property, 
-                        value.Value, 
-                        (BindingPriority)value.ValuePriority);
-                }
-                else
-                {
-                    yield return new PerspexPropertyValue(
-                        property, 
-                        this.GetValue(property),
-                        BindingPriority.Unset);
-                }
-            }
-        }
-
         /// <summary>
         /// Gets all properties that are registered on this object.
         /// </summary>
@@ -464,20 +435,6 @@ namespace Perspex
             }
         }
 
-        /// <summary>
-        /// Gets all of the <see cref="PerspexProperty"/> values explicitly set on this object.
-        /// </summary>
-        public IEnumerable<PerspexPropertyValue> GetSetValues()
-        {
-            foreach (var value in this.values)
-            {
-                yield return new PerspexPropertyValue(
-                    value.Key, 
-                    value.Value.Value,
-                    (BindingPriority)value.Value.ValuePriority);
-            }
-        }
-
         /// <summary>
         /// Checks whether a <see cref="PerspexProperty"/> is set on this object.
         /// </summary>
@@ -681,6 +638,15 @@ namespace Perspex
             }
         }
 
+        /// <summary>
+        /// Gets all priority values set on the object.
+        /// </summary>
+        /// <returns>A collection of property/value tuples.</returns>
+        internal IDictionary<PerspexProperty, PriorityValue> GetSetValues()
+        {
+            return this.values;
+        }
+
         /// <summary>
         /// Forces re-coercion of properties when a property value changes.
         /// </summary>

Perspex.Base/PerspexProperty.cs

@@ -361,7 +361,7 @@ namespace Perspex
         {
             public override string ToString()
             {
-                return "{Unset}";
+                return "(unset)";
             }
         }
     }

Perspex.Base/PriorityValue.cs

@@ -11,7 +11,7 @@ namespace Perspex
     using System.Linq;
     using System.Reactive.Subjects;
     using System.Reflection;
-    using Perspex.Diagnostics;
+    using System.Text;
 
     /// <summary>
     /// Maintains a list of prioritised bindings together with a current value.
@@ -171,6 +171,46 @@ namespace Perspex
             }
         }
 
+        /// <summary>
+        /// Returns diagnostic string that can help the user debug the bindings in effect on 
+        /// this object.
+        /// </summary>
+        /// <returns>A diagnostic string.</returns>
+        public string GetDiagnostic()
+        {
+            var b = new StringBuilder();
+            var first = true;
+
+            foreach (var level in this.levels)
+            {
+                if (!first)
+                {
+                    b.AppendLine();
+                }
+
+                b.Append(this.ValuePriority == level.Key ? "*" : "");
+                b.Append("Priority ");
+                b.Append(level.Key);
+                b.Append(": ");
+                b.AppendLine(level.Value.Value?.ToString() ?? "(null)");
+                b.AppendLine("--------");
+                b.Append("Direct: ");
+                b.AppendLine(level.Value.DirectValue.ToString());
+
+                foreach (var binding in level.Value.Bindings)
+                {
+                    b.Append(level.Value.ActiveBindingIndex == binding.Index ? "*" : "");
+                    b.Append(binding.Description ?? binding.Observable.GetType().Name);
+                    b.Append(": ");
+                    b.AppendLine(binding.Value.ToString());
+                }
+
+                first = false;
+            }
+
+            return b.ToString();
+        }
+
         /// <summary>
         /// Causes a re-coercion of the value.
         /// </summary>

Perspex.Diagnostics/Debug.cs

@@ -40,16 +40,21 @@ namespace Perspex.Diagnostics
                 builder.Append(" ");
                 builder.AppendLine(control.Classes.ToString());
 
-                foreach (var value in control.GetSetValues())
+                foreach (var property in control.GetRegisteredProperties())
                 {
-                    builder.Append(Indent(indent));
-                    builder.Append(" |  ");
-                    builder.Append(value.Property.Name);
-                    builder.Append(" = ");
-                    builder.Append(value.Value ?? "(null)");
-                    builder.Append(" [");
-                    builder.Append(value.Priority);
-                    builder.AppendLine("]");
+                    var value = control.GetDiagnostic(property);
+
+                    if (value.Priority != BindingPriority.Unset)
+                    {
+                        builder.Append(Indent(indent));
+                        builder.Append(" |  ");
+                        builder.Append(value.Property.Name);
+                        builder.Append(" = ");
+                        builder.Append(value.Value ?? "(null)");
+                        builder.Append(" [");
+                        builder.Append(value.Priority);
+                        builder.AppendLine("]");
+                    }
                 }
             }
             else

Perspex.Diagnostics/ViewModels/ControlDetailsViewModel.cs

@@ -17,8 +17,8 @@ namespace Perspex.Diagnostics.ViewModels
         {
             if (control != null)
             {
-                this.Properties = control.GetAllValues()
-                    .Select(x => new PropertyDetails(x))                    
+                this.Properties = control.GetRegisteredProperties()
+                    .Select(x => new PropertyDetails(control, x))
                     .OrderBy(x => x.Name)
                     .OrderBy(x => x.IsAttached);
             }

Perspex.Diagnostics/ViewModels/PropertyDetails.cs

@@ -13,32 +13,43 @@ namespace Perspex.Diagnostics.ViewModels
     {
         private object value;
 
-        public PropertyDetails(PerspexPropertyValue value)
+        private string priority;
+
+        private string diagnostic;
+
+        public PropertyDetails(PerspexObject o, PerspexProperty property)
         {
-            this.Name = value.Property.IsAttached ?
-                string.Format("[{0}.{1}]", value.Property.OwnerType.Name, value.Property.Name) :
-                value.Property.Name;
-            this.IsAttached = value.Property.IsAttached;
-
-            this.value = value.Value ?? "(null)";
-            this.Priority = (value.Priority != BindingPriority.Unset) ?
-                value.Priority.ToString() :
-                value.Property.Inherits ? "Inherited" : "Unset";
-
-            //if (value.PriorityValue != null)
-            //{
-            //    value.PriorityValue.Changed.Subscribe(x => this.Value = x.Item2);
-            //}
+            this.Name = property.IsAttached ?
+                string.Format("[{0}.{1}]", property.OwnerType.Name, property.Name) :
+                property.Name;
+            this.IsAttached = property.IsAttached;
+
+            // TODO: Unsubscribe when view model is deactivated.
+            o.GetObservable(property).Subscribe(x =>
+            {
+                var diagnostic = o.GetDiagnostic(property);
+                this.Value = diagnostic.Value ?? "(null)";
+                this.Priority = (diagnostic.Priority != BindingPriority.Unset) ?
+                    diagnostic.Priority.ToString() :
+                    diagnostic.Property.Inherits ? "Inherited" : "Unset";
+                this.Diagnostic = diagnostic.Diagnostic;
+            });
         }
 
-        public string Name
+        public string Name { get; }
+
+        public bool IsAttached { get; }
+
+        public string Priority
         {
-            get;
+            get { return this.priority; }
+            private set { this.RaiseAndSetIfChanged(ref this.priority, value); }
         }
 
-        public bool IsAttached
+        public string Diagnostic
         {
-            get;
+            get { return this.diagnostic; }
+            private set { this.RaiseAndSetIfChanged(ref this.diagnostic, value); }
         }
 
         public object Value
@@ -46,11 +57,5 @@ namespace Perspex.Diagnostics.ViewModels
             get { return this.value; }
             private set { this.RaiseAndSetIfChanged(ref this.value, value); }
         }
-
-        public string Priority
-        {
-            get;
-            private set;
-        }
     }
 }

Perspex.Diagnostics/Views/ControlDetailsView.cs

@@ -55,7 +55,7 @@ namespace Perspex.Diagnostics.Views
                             {
                                 new Setter(Control.MarginProperty, new Thickness(2)),
                             }
-                        }
+                        },
                     },
                     [GridRepeater.TemplateProperty] = pt,
                     [!GridRepeater.ItemsProperty] = this.WhenAnyValue(x => x.ViewModel.Properties),
@@ -69,7 +69,8 @@ namespace Perspex.Diagnostics.Views
 
             yield return new TextBlock
             {
-                Text = property.Name
+                Text = property.Name,
+                [!ToolTip.TipProperty] = property.WhenAnyValue(x => x.Diagnostic),
             };
 
             yield return new TextBlock
@@ -77,7 +78,10 @@ namespace Perspex.Diagnostics.Views
                 [!TextBlock.TextProperty] = property.WhenAnyValue(v => v.Value).Select(v => v?.ToString()),
             };
 
-            yield return new TextBlock { Text = property.Priority };
+            yield return new TextBlock
+            {
+                [!TextBlock.TextProperty] = property.WhenAnyValue(x => x.Priority),
+            };
         }
     }
 }