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VCF::Model Class Reference

A model is the base class for storing data that can then be presented to the user by controls and/or views. More...

#include <vcf/ApplicationKit/Model.h>

Inheritance diagram for VCF::Model:

List of all members.

Public Types
enum	ModelEvents { MODEL_CHANGED = 2000, MODEL_VALIDATED, MODEL_EMPTIED, MODEL_LAST_EVENT }
Public Member Functions
	Model ()
virtual	~Model ()
virtual ModelValidate void	validate ()
	Validate the model.
virtual bool	isEmpty ()
	Returns whether or not the model has an data.
virtual void	empty ()
	clears out the model's data
virtual void	addView (View *view)
	adds a new view to the model
virtual void	removeView (View *view)
	removes a view from the model
virtual void	updateAllViews ()
	notifies all the views the model has changed calls View::updateView( ), passing itself in as the updated Model
Enumerator< View * > *	getViews ()
void	changed (ModelEvent *event)
virtual VariantData	getValue (const VariantData &key=VariantData::null())
	Returns the value for the model.
virtual String	getValueAsString (const VariantData &key=VariantData::null())
	Returns the data for the model as a string.
virtual void	setValue (const VariantData &value, const VariantData &key=VariantData::null())
	Sets the value of the model.
virtual void	setValueAsString (const String &value, const VariantData &key=VariantData::null())
	Sets the value of the model using a string to specify the data.
bool	shouldDeleteVarObjects ()
	Indicates whether or not the model will be responsible for deleting objects that may be held in a collection of VariantData instances.
Public Attributes
VCF::Delegate	ModelDelegate
ModelChanged VCF::Delegate	ValidationDelegate
Protected Member Functions
virtual void	deleteVariantObject (Object *obj)
	A virtual method that deletes the object stored by the model.
Protected Attributes
bool	deleteVariantObjects_
	Indicates whether the model deletes the variant objects.
Array< View * >	views_

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Detailed Description

A model is the base class for storing data that can then be presented to the user by controls and/or views.

The model maintains zero or more views. It can update the views in one shot by the updateAllViews().

The exact kind of data store in the model is up to the implementor but all models has some basic common characteristics.

• They can be emptied or cleared out by calling the empty() method.
• You can determine is the model has any data at all by calling the isEmpty() method.
• A model's data can be "validated", in other words you can call validate() to determine if the data in the model is in a correct state, or has meaningful values. Again, the exact implementation is up to the programmer, but if the model is not considered "valid" then the validate() method must throw an exception.
• A model can notify interested parties that it's state or data has changed through it's ModelChanged delegate. Any time the data for the model is modified some sort of ModelEvent should be passed to the ModelChanged delegate to notify any of the associated callbacks.
• a generic method for retrieving data is provided (it may not be the best or most effient way to retreive data) via the getValue() method
• a generic method for setting/modifying data is provided (it may not be the best or most effient way to retreive data) via the setValue() method

Event Delegates for this class:

• Model::ModelChanged
• Model::ModelValidate

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Member Enumeration Documentation

enum VCF::Model::ModelEvents

Enumerator: MODEL_CHANGED  MODEL_VALIDATED  MODEL_EMPTIED  MODEL_LAST_EVENT

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Constructor & Destructor Documentation

VCF::Model::Model (   )

virtual VCF::Model::~Model (   )  [virtual]

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Member Function Documentation

virtual void VCF::Model::addView (  View *  view  )  [virtual]

adds a new view to the model

void VCF::Model::changed (  ModelEvent *  event  )  [inline]

virtual void VCF::Model::deleteVariantObject (  Object *  obj  )  [inline, protected, virtual]

A virtual method that deletes the object stored by the model. You may choose to override this with an alternate implementation.

virtual void VCF::Model::empty (   )  [inline, virtual]

clears out the model's data Reimplemented in VCF::DefaultTableModel, VCF::DefaultTextModel, VCF::DefaultTreeModel, VCF::SimpleListModel, VCF::TabModel, and VCF::TreeListModel.

virtual VariantData VCF::Model::getValue (  const VariantData &  key = VariantData::null()  )  [inline, virtual]

Returns the value for the model. A key may be specified with a VariantData object. The exact meaning of the key is up to the specific implementation Model based sub class. For example, a ListModel would expect a key that represents an integer based index. Another kind of model might use a string that represent's coordinates, or perhaps even an object instance that has relevant data for the key. Some models might ignore the key altogether, for example a TextModel might ignore the key and simply return the text of the model. Reimplemented in VCF::ListModel, and VCF::TextModel.

virtual String VCF::Model::getValueAsString (  const VariantData &  key = VariantData::null()  )  [inline, virtual]

Returns the data for the model as a string. See also: getValue Reimplemented in VCF::ListModel, and VCF::TextModel.

Enumerator<View*>* VCF::Model::getViews (   )  [inline]

virtual bool VCF::Model::isEmpty (   )  [inline, virtual]

Returns whether or not the model has an data. The default is true, since in it's abstract form the model doesn't (yet) have any data associated it. It is up to implementers to return something meaningful here. Reimplemented in VCF::DefaultTextModel, VCF::ListModel, VCF::TableModel, and VCF::TreeModel.

virtual void VCF::Model::removeView (  View *  view  )  [virtual]

removes a view from the model

virtual void VCF::Model::setValue (  const VariantData &  value, const VariantData &  key = VariantData::null() )  [inline, virtual]

Sets the value of the model. The data is stored in a VariantData object. The key may be used if it's relevant to the specific kind of model. See the getValue documentation for more information about the key parameter. See also: getValue Reimplemented in VCF::ListModel, and VCF::TextModel.

virtual void VCF::Model::setValueAsString (  const String &  value, const VariantData &  key = VariantData::null() )  [inline, virtual]

Sets the value of the model using a string to specify the data. See also: setValue() Reimplemented in VCF::ListModel, and VCF::TextModel.

bool VCF::Model::shouldDeleteVarObjects (   )  [inline]

Indicates whether or not the model will be responsible for deleting objects that may be held in a collection of VariantData instances. For example, if the model stored it's data using an array of VariantData objects, and each item in the array was a pointer to some Object based instance, then if the method returns true, the model will be responsible for freeing all the object instances stored in the array. If it returns false then the programmer would be responsible for freeing up the instances.

virtual void VCF::Model::updateAllViews (   )  [virtual]

notifies all the views the model has changed calls View::updateView( ), passing itself in as the updated Model

virtual ModelValidate void VCF::Model::validate (   )  [inline, virtual]

Validate the model. Reimplemented in VCF::DefaultTableModel.

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Member Data Documentation

bool VCF::Model::deleteVariantObjects_ [protected]

Indicates whether the model deletes the variant objects. If you need to set this, you should do so in your models constructor by accessing this variable directly. If you set it to true, the model should delete any object's it stores. See also: shouldDeleteVarObjects

VCF::Delegate VCF::Model::ModelDelegate

Event Delegate: ModelChanged fired when the model's empty() method is called. Should also be fired for any change to the model's content. event class: ModelEvent event type: Model::MODEL_EMPTIED See also: empty()

ModelChanged VCF::Delegate VCF::Model::ValidationDelegate

Event Delegate: ModelValidate fired when the model's validate() method is called event class: ValidationEvent See also: validate()

Array<View*> VCF::Model::views_ [protected]

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The documentation for this class was generated from the following file:

• vcf/ApplicationKit/Model.h

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