diff options
Diffstat (limited to 'forms/source/xforms/propertysetbase.hxx')
| -rw-r--r-- | forms/source/xforms/propertysetbase.hxx | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/forms/source/xforms/propertysetbase.hxx b/forms/source/xforms/propertysetbase.hxx new file mode 100644 index 000000000..d6ae97405 --- /dev/null +++ b/forms/source/xforms/propertysetbase.hxx @@ -0,0 +1,340 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you under the Apache + * License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of + * the License at http://www.apache.org/licenses/LICENSE-2.0 . + */ +#pragma once + +#include <comphelper/propstate.hxx> +#include <rtl/ref.hxx> +#include <salhelper/simplereferenceobject.hxx> + +// include for inlined helper function below +#include <com/sun/star/beans/PropertyAttribute.hpp> + +#include <map> +#include <memory> + +namespace com::sun::star::uno { + class Any; + class RuntimeException; + template<class T> class Sequence; +} + +/** base class which encapsulates accessing (reading/writing) concrete property values +*/ +class PropertyAccessorBase : public salhelper::SimpleReferenceObject +{ +protected: + PropertyAccessorBase() { } + virtual ~PropertyAccessorBase() override; + +public: + + virtual bool approveValue( const css::uno::Any& rValue ) const = 0; + virtual void setValue( const css::uno::Any& rValue ) = 0; + virtual void getValue( css::uno::Any& rValue ) const = 0; + virtual bool isWriteable() const = 0; +}; + + +/** helper class for implementing property accessors through public member functions +*/ +template< typename CLASS, typename VALUE, class WRITER, class READER > +class GenericPropertyAccessor : public PropertyAccessorBase +{ +public: + typedef WRITER Writer; + typedef READER Reader; + +private: + CLASS* m_pInstance; + Writer m_pWriter; + Reader m_pReader; + +public: + GenericPropertyAccessor( CLASS* pInstance, Writer pWriter, Reader pReader ) + :m_pInstance( pInstance ) + ,m_pWriter( pWriter ) + ,m_pReader( pReader ) + { + } + + virtual bool approveValue( const css::uno::Any& rValue ) const override + { + VALUE aVal; + return ( rValue >>= aVal ); + } + + virtual void setValue( const css::uno::Any& rValue ) override + { + VALUE aTypedVal = VALUE(); + OSL_VERIFY( rValue >>= aTypedVal ); + (m_pInstance->*m_pWriter)( aTypedVal ); + } + + virtual void getValue( css::uno::Any& rValue ) const override + { + rValue = css::uno::Any( (m_pInstance->*m_pReader)() ); + } + + virtual bool isWriteable() const override + { + return m_pWriter != nullptr; + } +}; + +/** helper class for implementing property accessors via non-UNO methods +*/ +template< typename CLASS, typename VALUE > +class DirectPropertyAccessor + :public GenericPropertyAccessor < CLASS + , VALUE + , void (CLASS::*)( const VALUE& ) + , VALUE (CLASS::*)() const + > +{ +protected: + typedef void (CLASS::*Writer)( const VALUE& ); + typedef VALUE (CLASS::*Reader)() const; +public: + DirectPropertyAccessor( CLASS* pInstance, Writer pWriter, Reader pReader ) + :GenericPropertyAccessor< CLASS, VALUE, Writer, Reader >( pInstance, pWriter, pReader ) + { + } +}; + +/** helper class for implementing non-UNO accessors to a boolean property +*/ +template< typename CLASS > +class BooleanPropertyAccessor + :public GenericPropertyAccessor < CLASS + , bool + , void (CLASS::*)( bool ) + , bool (CLASS::*)() const + > +{ +protected: + typedef void (CLASS::*Writer)( bool ); + typedef bool (CLASS::*Reader)() const; +public: + BooleanPropertyAccessor( CLASS* pInstance, Writer pWriter, Reader pReader ) + :GenericPropertyAccessor< CLASS, bool, Writer, Reader >( pInstance, pWriter, pReader ) + { + } +}; + +/** helper class for implementing property accessors via UNO methods +*/ +template< typename CLASS, typename VALUE > +class APIPropertyAccessor + :public GenericPropertyAccessor < CLASS + , VALUE + , void (SAL_CALL CLASS::*)( const VALUE& ) + , VALUE (SAL_CALL CLASS::*)() + > +{ +protected: + typedef void (SAL_CALL CLASS::*Writer)( const VALUE& ); + typedef VALUE (SAL_CALL CLASS::*Reader)(); +public: + APIPropertyAccessor( CLASS* pInstance, Writer pWriter, Reader pReader ) + :GenericPropertyAccessor< CLASS, VALUE, Writer, Reader >( pInstance, pWriter, pReader ) + { + } +}; + +/** bridges two XPropertySet helper implementations + + The <type scope="comphelper">OStatefulPropertySet</type> (basically, the + <type scope="cppu">OPropertySetHelper</type>) implements a comprehensive framework + for property sets, including property change notifications. + However, it lacks some easy possibilities to declare the supported properties. + Other helper structs and classes allow for this, but are lacking needed features + such as property change notifications. + + The <type>PropertySetBase</type> bridges various implementations, + so you have the best of both worlds. + */ +class PropertySetBase : public ::comphelper::OStatefulPropertySet +{ +private: + typedef ::std::map< const sal_Int32, ::rtl::Reference< PropertyAccessorBase > > PropertyAccessors; + typedef ::std::vector< css::beans::Property > PropertyArray; + typedef ::std::map< const sal_Int32, css::uno::Any > PropertyValueCache; + + PropertyArray m_aProperties; + std::unique_ptr<cppu::IPropertyArrayHelper> m_pProperties; + PropertyAccessors m_aAccessors; + PropertyValueCache m_aCache; + +protected: + PropertySetBase(); + virtual ~PropertySetBase() override; + + /** registers a new property to be supported by this instance + @param rProperty + the descriptor for the to-be-supported property + @param rAccessor + an instance which is able to provide read and possibly write access to + the property. + @precond + Must not be called after any of the property set related UNO interfaces + has been used. Usually, you will do a number of <member>registerProperty</member> + calls in the constructor of your class. + */ + void registerProperty( + const css::beans::Property& rProperty, + const ::rtl::Reference< PropertyAccessorBase >& rAccessor + ); + + /** notifies a change in a given property value, if necessary + + The necessity of the notification is determined by a cached value for the given + property. Caching happens after notification. + + That is, when you call <member>notifyAndCachePropertyValue</member> for the first time, + a value for the given property is default constructed, and considered to be the "old value". + If this value differs from the current value, then this change is notified to all interested + listeners. Finally, the current value is remembered. + + Subsequent calls to <member>notifyAndCachePropertyValue</member> use the remembered value as + "old value", and from then on behave as the first call. + + @param nHandle + the handle of the property. Must denote a property supported by this instance, i.e. + one previously registered via <member>registerProperty</member>. + + @precond + our ref count must not be 0. The reason is that during this method's execution, + the instance might be acquired and released, which would immediately destroy + the instance if it has a ref count of 0. + + @seealso initializePropertyValueCache + */ + void notifyAndCachePropertyValue( sal_Int32 nHandle ); + + /** initializes the property value cache for the given property, with its current value + + Usually used to initialize the cache with values which are different from default + constructed values. Say you have a boolean property whose initial state + is <TRUE/>. Say you call <member>notifyAndCachePropertyValue</member> the first time: it will + default construct the "old value" for this property as <FALSE/>, and thus <b>not</b> do + any notifications if the "current value" is also <FALSE/> - which might be wrong, since + the guessing of the "old value" differed from the real initial value which was <TRUE/>. + + Too confusing? Okay, then just call this method for every property you have. + + @param nHandle + the handle of the property. Must denote a property supported by this instance, i.e. + one previously registered via <member>registerProperty</member>. + @param rValue + the value to cache + @seealso notifyAndCachePropertyValue + */ + void initializePropertyValueCache( sal_Int32 nHandle ); + + /// OPropertysetHelper methods + virtual sal_Bool SAL_CALL convertFastPropertyValue( css::uno::Any& rConvertedValue, css::uno::Any& rOldValue, sal_Int32 nHandle, const css::uno::Any& rValue ) override; + virtual void SAL_CALL setFastPropertyValue_NoBroadcast( sal_Int32 nHandle, const css::uno::Any& rValue ) override; + virtual void SAL_CALL getFastPropertyValue( css::uno::Any& rValue, sal_Int32 nHandle ) const override; + + virtual cppu::IPropertyArrayHelper& SAL_CALL getInfoHelper() override; + virtual css::uno::Reference< css::beans::XPropertySetInfo > SAL_CALL getPropertySetInfo( ) override; + +public: + /// helper struct for granting selective access to some notification-related methods + struct NotifierAccess { friend struct PropertyChangeNotifier; private: NotifierAccess() { } }; + /** retrieves the current property value for the given handle + @param nHandle + the handle of the property. Must denote a property supported by this instance, i.e. + one previously registered via <member>registerProperty</member>. + @see registerProperty + */ + void getCurrentPropertyValueByHandle( sal_Int32 nHandle, css::uno::Any& /* [out] */ rValue, const NotifierAccess& ) const + { + getFastPropertyValue( rValue, nHandle ); + } + + /** notifies a change in a given property to all interested listeners + */ + void notifyPropertyChange( sal_Int32 nHandle, const css::uno::Any& rOldValue, const css::uno::Any& rNewValue, const NotifierAccess& ) const + { + const_cast< PropertySetBase* >( this )->firePropertyChange( nHandle, rNewValue, rOldValue ); + } + + using ::comphelper::OStatefulPropertySet::getFastPropertyValue; + +private: + /** locates a property given by handle + @param nHandle + the handle of the property. Must denote a property supported by this instance, i.e. + one previously registered via <member>registerProperty</member>. + @see registerProperty + */ + PropertyAccessorBase& locatePropertyHandler( sal_Int32 nHandle ) const; +}; + +/** a helper class for notifying property changes in a <type>PropertySetBase</type> instance. + + You can create an instance of this class on the stack of a method which is to programmatically + change the value of a property. In its constructor, the instance will acquire the current property + value, and in its destructor, it will notify the change of this property's value (if necessary). + + You do not need this class if you are modifying property values by using the X(Fast|Multi)PropertSet + methods, since those already care for property notifications. You only need it if you're changing + the internal representation of your property directly. + + Also note that usually, notifications in the UNO world should be done without a locked mutex. So + if you use this class in conjunction with a <type>MutexGuard</type>, ensure that you <b>first</b> + instantiate the <type>PropertyChangeNotifier</type>, and <b>then</b> the <type>MutexGuard</type>, + so your mutex is released before the notification happens. +*/ +struct PropertyChangeNotifier +{ +private: + const PropertySetBase& m_rPropertySet; + sal_Int32 m_nHandle; + css::uno::Any m_aOldValue; + +public: + /** constructs a PropertyChangeNotifier + @param rPropertySet + the property set implementation whose property is going to be changed. Note + that this property set implementation must live at least as long as the + PropertyChangeNotifier instance does. + @param nHandle + the handle of the property which is going to be changed. Must be a valid property + handle for the given <arg>rPropertySet</arg> + */ + PropertyChangeNotifier( const PropertySetBase& rPropertySet, sal_Int32 nHandle ) + :m_rPropertySet( rPropertySet ) + ,m_nHandle( nHandle ) + { + m_rPropertySet.getCurrentPropertyValueByHandle( m_nHandle, m_aOldValue, PropertySetBase::NotifierAccess() ); + } + ~PropertyChangeNotifier() + { + css::uno::Any aNewValue; + m_rPropertySet.getCurrentPropertyValueByHandle( m_nHandle, aNewValue, PropertySetBase::NotifierAccess() ); + if ( aNewValue != m_aOldValue ) + { + m_rPropertySet.notifyPropertyChange( m_nHandle, m_aOldValue, aNewValue, PropertySetBase::NotifierAccess() ); + } + } +}; + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |