src/provider.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
   2 /*
   3  * provider.h: an api for PropertyValue providers (for property inheritance)
   4  *
   5  * Copyright 2007 Novell, Inc. (http://www.novell.com)
   6  *
   7  * See the LICENSE file included with the distribution for details.
   8  *
   9  */
  10
  11 #ifndef __MOON_PROVIDER_H__
  12 #define __MOON_PROVIDER_H__
  13
  14 #include <glib.h>
  15
  16 #include "type.h"
  17
  18 class DependencyObject;
  19 class DependencyProperty;
  20 class UIElement;
  21 class Surface;
  22 class Style;
  23 struct Value;
  24
  25 enum PropertyPrecedence {
  26         PropertyPrecedence_LocalValue,
  27         PropertyPrecedence_DynamicValue, // use this level for types that need to compute property values lazily
  28
  29         PropertyPrecedence_LocalStyle,
  30         PropertyPrecedence_DefaultStyle,
  31
  32         PropertyPrecedence_Inherited,
  33         PropertyPrecedence_DefaultValue,
  34         PropertyPrecedence_AutoCreate,
  35
  36         PropertyPrecedence_Count,
  37
  38         PropertyPrecedence_Highest = PropertyPrecedence_LocalValue,
  39         PropertyPrecedence_Lowest = PropertyPrecedence_AutoCreate,
  40 };
  41
  42 class PropertyValueProvider {
  43 public:
  44         PropertyValueProvider (DependencyObject *_obj, PropertyPrecedence _precedence) : obj(_obj), precedence(_precedence) { }
  45         virtual ~PropertyValueProvider () { }
  46
  47         virtual Value *GetPropertyValue (DependencyProperty *property) = 0;
  48
  49         virtual void RecomputePropertyValue (DependencyProperty *property) { }
  50
  51 protected:
  52         DependencyObject *obj;
  53         PropertyPrecedence precedence;
  54 };
  55
  56
  57 class LocalPropertyValueProvider : public PropertyValueProvider {
  58 public:
  59         LocalPropertyValueProvider (DependencyObject *obj, PropertyPrecedence _precedence);
  60         virtual ~LocalPropertyValueProvider ();
  61
  62         virtual Value *GetPropertyValue (DependencyProperty *property);
  63 };
  64
  65 class StylePropertyValueProvider : public PropertyValueProvider {
  66 public:
  67         StylePropertyValueProvider (DependencyObject *obj, PropertyPrecedence _precedence);
  68         virtual ~StylePropertyValueProvider ();
  69
  70         virtual Value *GetPropertyValue (DependencyProperty *property);
  71
  72         virtual void RecomputePropertyValue (DependencyProperty *property);
  73
  74         void SealStyle (Style *style);
  75
  76 private:
  77         GHashTable *style_hash;
  78         static void unlink_converted_value (gpointer key, gpointer value, gpointer data);
  79 };
  80
  81 class InheritedPropertyValueProvider : public PropertyValueProvider {
  82 public:
  83         InheritedPropertyValueProvider (DependencyObject *obj, PropertyPrecedence _precedence) : PropertyValueProvider (obj, precedence) { };
  84         virtual ~InheritedPropertyValueProvider () { };
  85
  86         virtual Value *GetPropertyValue (DependencyProperty *property);
  87
  88         static bool IsPropertyInherited (int propertyId);
  89
  90
  91         // this method is used when a property changes on object @obj,
  92         // and that notification needs to propagate down the tree
  93         static void PropagateInheritedProperty (DependencyObject *obj, DependencyProperty *property, Value *old_value, Value *new_value);
  94
  95         // this method is used when you add a subtree into a
  96         // pre-existing tree.  it propagates all inheritable
  97         // properties throughout the tree
  98         static void PropagateInheritedPropertiesOnAddingToTree (UIElement *subtreeRoot);
  99 private:
 100
 101         // given a dependency property and a descendent, this maps the
 102         // property to whatever corresponds to that property on the
 103         // descendent.
 104         //
 105         // i.e. Control::ForegroundProperty + Type::TEXTBLOCK = TextBlock::ForegroundProperty
 106         //
 107         static DependencyProperty* MapPropertyToDescendant (Types *types,
 108                                                             DependencyProperty *property,
 109                                                             Type::Kind descendantKind);
 110 };
 111
 112 class DefaultValuePropertyValueProvider : public PropertyValueProvider {
 113 public:
 114         DefaultValuePropertyValueProvider (DependencyObject *obj, PropertyPrecedence _precedence) : PropertyValueProvider (obj, precedence) { };
 115         virtual ~DefaultValuePropertyValueProvider () { };
 116
 117         virtual Value *GetPropertyValue (DependencyProperty *property);
 118 };
 119
 120 typedef Value* AutoCreator  (DependencyObject *instance, DependencyProperty *property);
 121
 122 class AutoCreators {
 123 public:
 124         static AutoCreator default_autocreator;
 125
 126         static AutoCreator CreateDefaultFontSize;
 127 };
 128
 129 class AutoCreatePropertyValueProvider : public PropertyValueProvider {
 130  public:
 131         GHashTable *auto_values;
 132
 133         AutoCreatePropertyValueProvider (DependencyObject *obj, PropertyPrecedence _precedence);
 134         virtual ~AutoCreatePropertyValueProvider ();
 135
 136         virtual Value *GetPropertyValue (DependencyProperty *property);
 137
 138         Value *ReadLocalValue (DependencyProperty *property);
 139         void ClearValue (DependencyProperty *property);
 140 };
 141
 142
 143 #endif /* __MOON_PROVIDER_H__ */