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java.lang.Objectcom.trolltech.qt.QSignalEmitter
com.trolltech.qt.QtJambiObject
com.trolltech.qt.core.QObject
com.trolltech.qt.core.QAbstractItemModel
public abstract class QAbstractItemModel
The QAbstractItemModel
class provides the abstract interface for item model classes. The QAbstractItemModel
class defines the standard interface that item models must use to be able to interoperate with other components in the model/view architecture. It is not supposed to be instantiated directly. Instead, you should subclass it to create new models.
The QAbstractItemModel
class is one of the Model/View Classes and is part of Qt's model/view framework.
If you need a model to use with a QListView
or a QTableView
, you should consider subclassing QAbstractListModel
or QAbstractTableModel
instead of this class.
The underlying data model is exposed to views and delegates as a hierarchy of tables. If you don't make use of the hierarchy, then the model is a simple table of rows and columns. Each item has a unique index specified by a QModelIndex.
index()
function. Each index may have a sibling()
index; child items have a parent()
index. Each item has a number of data elements associated with it, and each of these can be retrieved by specifying a role (see Qt::ItemDataRole
) to the model's data()
function. Data for all available roles can be obtained at the same time using the itemData()
function.
Data for each role is set using a particular Qt::ItemDataRole
. Data for individual roles are set individually with setData()
, or they can be set for all roles with setItemData()
.
Items can be queried with flags()
(see Qt::ItemFlag
) to see if they can be selected, dragged, or manipulated in other ways.
If an item has child objects, hasChildren()
returns true for the corresponding index.
The model has a rowCount()
and a columnCount()
for each level of the hierarchy. Rows and columns can be inserted and removed with insertRows()
, insertColumns()
, removeRows()
, and removeColumns()
.
The model emits signals to indicate changes. For example, dataChanged()
is emitted whenever items of data made available by the model are changed. Changes to the headers supplied by the model cause headerDataChanged()
to be emitted. If the structure of the underlying data changes, the model can emit layoutChanged()
to indicate to any attached views that they should redisplay any items shown, taking the new structure into account.
The items available through the model can be searched for particular data using the match()
function.
If the model is sortable, it can be sorted with sort()
.Subclassing
Note: Some general guidelines for subclassing models are available in the Model Subclassing Reference.
When subclassing QAbstractItemModel
, at the very least you must implement index()
, parent()
, rowCount()
, columnCount()
, and data()
. These functions are used in all read-only models, and form the basis of editable models.
You can also reimplement hasChildren()
to provide special behavior for models where the implementation of rowCount()
is expensive. This makes it possible for models to restrict the amount of data requested by views, and can be used as a way to implement lazy population of model data.
To enable editing in your model, you must also implement setData()
, and reimplement flags()
to ensure that ItemIsEditable is returned. You can also reimplement headerData()
and setHeaderData()
to control the way the headers for your model are presented.
Note that the dataChanged()
and headerDataChanged()
signals must be emitted explicitly when reimplementing the setData()
and setHeaderData()
functions, respectively.
Custom models need to create model indexes for other components to use. To do this, call createIndex()
with suitable row and column numbers for the item, and an identifier for it, either as a pointer or as an integer value. The combination of these values must be unique for each item. Custom models typically use these unique identifiers in other reimplemented functions to retrieve item data and access information about the item's parents and children. See the Simple Tree Model example for more information about unique identifiers.
It is not necessary to support every role defined in Qt::ItemDataRole
. Depending on the type of data contained within a model, it may only be useful to implement the data()
function to return valid information for some of the more common roles. Most models provide at least a textual representation of item data for the Qt::DisplayRole
, and well-behaved models should also provide valid information for the Qt::ToolTipRole
and Qt::WhatsThisRole
. Supporting these roles enables models to be used with standard Qt views. However, for some models that handle highly-specialized data, it may be appropriate to provide data only for user-defined roles.
Models that provide interfaces to resizable data structures can provide implementations of insertRows()
, removeRows()
, insertColumns()
, and removeColumns()
. When implementing these functions, it is important to notify any connected views about changes to the model's dimensions both before and after they occur:
insertRows()
implementation must call beginInsertRows()
before inserting new rows into the data structure, and it must call endInsertRows()
immediately afterwards.insertColumns()
implementation must call beginInsertColumns()
before inserting new columns into the data structure, and it must call endInsertColumns()
immediately afterwards.removeRows()
implementation must call beginRemoveRows()
before the rows are removed from the data structure, and it must call endRemoveRows()
immediately afterwards.removeColumns()
implementation must call beginRemoveColumns()
before the columns are removed from the data structure, and it must call endRemoveColumns()
immediately afterwards.persistent model indexes
correctly. If you want selections to be handled properly, you must ensure that you call these functions. QAbstractItemView
, Using Drag and Drop with Item Views, Simple DOM Model Example, and Simple Tree Model Example.
Nested Class Summary |
---|
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter |
---|
QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9 |
Field Summary | |
---|---|
QSignalEmitter.Signal2 |
dataChanged
This signal is emitted whenever the data in an existing item changes. |
QSignalEmitter.Signal3 |
headerDataChanged
This signal is emitted whenever a header is changed. |
QSignalEmitter.Signal0 |
layoutAboutToBeChanged
This signal is emitted just before the layout of a model is changed. |
QSignalEmitter.Signal0 |
layoutChanged
This signal is emitted whenever the layout of items exposed by the model has changed; for example, when the model has been sorted. |
Constructor Summary | |
---|---|
QAbstractItemModel()
Constructs an abstract item model with the given parent. |
|
QAbstractItemModel(QObject parent)
Constructs an abstract item model with the given parent. |
Method Summary | |
---|---|
protected void |
beginInsertColumns(QModelIndex parent,
int first,
int last)
Begins a column insertion operation. |
protected void |
beginInsertRows(QModelIndex parent,
int first,
int last)
Begins a row insertion operation. |
protected void |
beginRemoveColumns(QModelIndex parent,
int first,
int last)
Begins a column removal operation. |
protected void |
beginRemoveRows(QModelIndex parent,
int first,
int last)
Begins a row removal operation. |
QModelIndex |
buddy(QModelIndex index)
Returns a model index for the buddy of the item represented by index. |
boolean |
canFetchMore(QModelIndex parent)
Returns true if there is more data available for parent, otherwise false. |
protected void |
changePersistentIndex(QModelIndex from,
QModelIndex to)
Changes the QPersistentModelIndex that is equal to the given from model index to the given to model index. |
protected void |
changePersistentIndexList(java.util.List from,
java.util.List to)
Changes the QPersistentModelIndexes that is equal to the indexes in the given from model index list to the given to model index list. |
int |
columnCount()
Returns the number of columns for the children of the given parent. |
abstract int |
columnCount(QModelIndex parent)
Returns the number of columns for the children of the given parent. |
protected QModelIndex |
createIndex(int row,
int column)
Creates a model index for the given row and column with the internal pointer ptr. |
protected QModelIndex |
createIndex(int row,
int column,
int id)
Use QModelIndexQAbstractItemModel.:createIndex(int row, int column, quint32 id) instead. |
protected QModelIndex |
createIndex(int row,
int column,
QNativePointer data)
Creates a model index for the given row and column with the internal pointer ptr. |
java.lang.Object |
data(int row,
int col)
Returns the data in the display role at row row and column col. |
java.lang.Object |
data(int row,
int col,
int role)
Returns the data with the specified role at row row and column col |
java.lang.Object |
data(QModelIndex index)
Returns the data stored under the given role for the item referred to by the index. |
abstract java.lang.Object |
data(QModelIndex index,
int role)
Returns the data stored under the given role for the item referred to by the index. |
boolean |
dropMimeData(QMimeData data,
Qt.DropAction action,
int row,
int column,
QModelIndex parent)
Handles the data supplied by a drag and drop operation that ended with the given action. |
protected void |
endInsertColumns()
Ends a column insertion operation. |
protected void |
endInsertRows()
Ends a row insertion operation. |
protected void |
endRemoveColumns()
Ends a column removal operation. |
protected void |
endRemoveRows()
Ends a row removal operation. |
void |
fetchMore(QModelIndex parent)
Fetches any available data for the items with the parent specified by the parent index. |
Qt.ItemFlags |
flags(QModelIndex index)
Returns the item flags for the given index. |
static QAbstractItemModel |
fromNativePointer(QNativePointer nativePointer)
|
boolean |
hasChildren()
Returns true if parent has any children; otherwise returns false. |
boolean |
hasChildren(QModelIndex parent)
Returns true if parent has any children; otherwise returns false. |
boolean |
hasIndex(int row,
int column)
Returns true if the model returns a valid QModelIndex for row and column with parent, otherwise returns false. |
boolean |
hasIndex(int row,
int column,
QModelIndex parent)
Returns true if the model returns a valid QModelIndex for row and column with parent, otherwise returns false. |
java.lang.Object |
headerData(int section,
Qt.Orientation orientation)
Returns the data for the given role and section in the header with the specified orientation. |
java.lang.Object |
headerData(int section,
Qt.Orientation orientation,
int role)
Returns the data for the given role and section in the header with the specified orientation. |
QModelIndex |
index(int row,
int column)
Returns the index of the item in the model specified by the given row, column and parent index. |
abstract QModelIndex |
index(int row,
int column,
QModelIndex parent)
Returns the index of the item in the model specified by the given row, column and parent index. |
boolean |
insertColumn(int column)
Inserts a single column before the given column in the child items of the parent specified. |
boolean |
insertColumn(int column,
QModelIndex parent)
Inserts a single column before the given column in the child items of the parent specified. |
boolean |
insertColumns(int column,
int count)
On models that support this, inserts count new columns into the model before the given column. |
boolean |
insertColumns(int column,
int count,
QModelIndex parent)
On models that support this, inserts count new columns into the model before the given column. |
boolean |
insertRow(int row)
Inserts a single row before the given row in the child items of the parent specified. |
boolean |
insertRow(int row,
QModelIndex parent)
Inserts a single row before the given row in the child items of the parent specified. |
boolean |
insertRows(int row,
int count)
On models that support this, inserts count rows into the model before the given row. |
boolean |
insertRows(int row,
int count,
QModelIndex parent)
On models that support this, inserts count rows into the model before the given row. |
java.util.SortedMap |
itemData(QModelIndex index)
Returns a map with values for all predefined roles in the model for the item at the given index. |
java.util.List |
match(QModelIndex start,
int role,
java.lang.Object value)
This is an overloaded function provided for convenience. |
java.util.List |
match(QModelIndex start,
int role,
java.lang.Object value,
int hits)
This is an overloaded function provided for convenience. |
java.util.List |
match(QModelIndex start,
int role,
java.lang.Object value,
int hits,
Qt.MatchFlag[] flags)
Returns a list of indexes for the items in the column of the start index where the data stored under the given role matches the specified value. |
java.util.List |
match(QModelIndex start,
int role,
java.lang.Object value,
int hits,
Qt.MatchFlags flags)
Returns a list of indexes for the items in the column of the start index where the data stored under the given role matches the specified value. |
QMimeData |
mimeData(java.util.List indexes)
Returns an object that contains serialized items of data corresponding to the list of indexes specified. |
java.util.List |
mimeTypes()
Returns a list of MIME types that can be used to describe a list of model indexes. |
abstract QModelIndex |
parent(QModelIndex child)
Returns the parent of the model item with the given index, or QModelIndex() if it has no parent. |
protected java.util.List |
persistentIndexList()
Returns the list of indexes stored as persistent indexes in the model. |
boolean |
removeColumn(int column)
Removes the given column from the child items of the parent specified. |
boolean |
removeColumn(int column,
QModelIndex parent)
Removes the given column from the child items of the parent specified. |
boolean |
removeColumns(int column,
int count)
On models that support this, removes count columns starting with the given column under parent parent from the model. |
boolean |
removeColumns(int column,
int count,
QModelIndex parent)
On models that support this, removes count columns starting with the given column under parent parent from the model. |
boolean |
removeRow(int row)
Removes the given row from the child items of the parent specified. |
boolean |
removeRow(int row,
QModelIndex parent)
Removes the given row from the child items of the parent specified. |
boolean |
removeRows(int row,
int count)
On models that support this, removes count rows starting with the given row under parent parent from the model. |
boolean |
removeRows(int row,
int count,
QModelIndex parent)
On models that support this, removes count rows starting with the given row under parent parent from the model. |
protected void |
reset()
Resets the model to its original state in any attached views. |
void |
revert()
Called to let the model know that it should discard whatever it has cached. |
int |
rowCount()
Returns the number of rows under the given parent. |
abstract int |
rowCount(QModelIndex parent)
Returns the number of rows under the given parent. |
boolean |
setData(int row,
int col,
java.lang.Object value)
Sets the data for the item at row and col to value. |
boolean |
setData(int row,
int col,
java.lang.Object value,
int role)
Sets the models data at row and col to value. |
boolean |
setData(QModelIndex index,
java.lang.Object value)
Sets the role data for the item at index to value. |
boolean |
setData(QModelIndex index,
java.lang.Object value,
int role)
Sets the role data for the item at index to value. |
boolean |
setHeaderData(int section,
Qt.Orientation orientation,
java.lang.Object value)
Sets the data for the given role and section in the header with the specified orientation to the value supplied. |
boolean |
setHeaderData(int section,
Qt.Orientation orientation,
java.lang.Object value,
int role)
Sets the data for the given role and section in the header with the specified orientation to the value supplied. |
boolean |
setItemData(QModelIndex index,
java.util.SortedMap roles)
This is an overloaded function provided for convenience. |
void |
setSupportedDragActions(Qt.DropAction[] arg__1)
Sets the supported drag actions for the items in the model. |
void |
setSupportedDragActions(Qt.DropActions arg__1)
Sets the supported drag actions for the items in the model. |
QModelIndex |
sibling(int row,
int column,
QModelIndex idx)
Returns the sibling at row and column for the item at index, or an invalid QModelIndex if there is no sibling at that location. |
void |
sort(int column)
Sorts the model by column in the given order. |
void |
sort(int column,
Qt.SortOrder order)
Sorts the model by column in the given order. |
QSize |
span(QModelIndex index)
Returns the row and column span of the item represented by index. |
boolean |
submit()
Called to let the model know that it should submit whatever it has cached to the permanent storage. |
Qt.DropActions |
supportedDragActions()
Returns the actions supported by the data in this model. |
Qt.DropActions |
supportedDropActions()
Returns the drop actions supported by this model. |
Methods inherited from class com.trolltech.qt.core.QObject |
---|
childEvent, children, connectSlotsByName, customEvent, disposeLater, dumpObjectInfo, dumpObjectTree, dynamicPropertyNames, event, eventFilter, findChild, findChild, findChild, findChildren, findChildren, findChildren, findChildren, indexOfProperty, installEventFilter, isWidgetType, killTimer, moveToThread, objectName, parent, properties, property, removeEventFilter, setObjectName, setParent, setProperty, startTimer, timerEvent, toString, userProperty |
Methods inherited from class com.trolltech.qt.QtJambiObject |
---|
dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr |
Methods inherited from class com.trolltech.qt.QSignalEmitter |
---|
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread |
Methods inherited from class java.lang.Object |
---|
clone, getClass, hashCode, notify, notifyAll, wait, wait, wait |
Methods inherited from interface com.trolltech.qt.QtJambiInterface |
---|
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership |
Field Detail |
---|
public final QSignalEmitter.Signal2 dataChanged
Note that this signal must be emitted explicitly when reimplementing the setData()
function.
headerDataChanged()
, setData()
, and layoutChanged()
.
public final QSignalEmitter.Signal3 headerDataChanged
Note that this signal must be emitted explicitly when reimplementing the setHeaderData()
function.
If you are changing the number of columns or rows you don't need to emit this signal, but use the begin/end functions.
headerData()
, setHeaderData()
, and dataChanged()
.
public final QSignalEmitter.Signal0 layoutAboutToBeChanged
Subclasses should update any persistent model indexes after emitting layoutAboutToBeChanged()
.
layoutChanged()
, and changePersistentIndex()
.
public final QSignalEmitter.Signal0 layoutChanged
When subclassing QAbstractItemModel
or QAbstractProxyModel
, ensure that you emit layoutAboutToBeChanged()
before changing the order of items or altering the structure of the data you expose to views, and emit layoutChanged()
after changing the layout.
Subclasses should update any persistent model indexes before emitting layoutChanged()
.
layoutAboutToBeChanged()
, dataChanged()
, headerDataChanged()
, reset()
, and changePersistentIndex()
.
Constructor Detail |
---|
public QAbstractItemModel()
public QAbstractItemModel(QObject parent)
Method Detail |
---|
protected final void beginInsertColumns(QModelIndex parent, int first, int last)
When reimplementing insertColumns()
in a subclass, you must call this function before inserting data into the model's underlying data store.
The parent index corresponds to the parent into which the new columns are inserted; first and last are the column numbers of the new columns will have after they have been inserted.
![]() | Specify the first and last column numbers for the span of columns you want to insert into an item in a model. For example, as shown in the diagram, we insert three columns before column 4, so first is 4 and last is 6: itemModel.beginInsertColumns(null, 4, 6);This inserts the three new columns as columns 4, 5, and 6. |
![]() | To append columns, insert them after the last column. For example, as shown in the diagram, we append three columns to a collection of six existing columns (ending in column 5), so first is 6 and last is 8: itemModel.beginInsertColumns(null, 6, 8);This appends the two new columns as columns 6, 7, and 8. |
endInsertColumns()
.
protected final void beginInsertRows(QModelIndex parent, int first, int last)
When reimplementing insertRows()
in a subclass, you must call this function before inserting data into the model's underlying data store.
The parent index corresponds to the parent into which the new rows are inserted; first and last are the row numbers that the new rows will have after they have been inserted.
![]() | Specify the first and last row numbers for the span of rows you want to insert into an item in a model. For example, as shown in the diagram, we insert three rows before row 2, so first is 2 and last is 4: itemModel.beginInsertRows(null, 2, 4);This inserts the three new rows as rows 2, 3, and 4. |
![]() | To append rows, insert them after the last row. For example, as shown in the diagram, we append two rows to a collection of 4 existing rows (ending in row 3), so first is 4 and last is 5: itemModel.beginInsertRows(null, 4, 5);This appends the two new rows as rows 4 and 5. |
endInsertRows()
.
protected final void beginRemoveColumns(QModelIndex parent, int first, int last)
When reimplementing removeColumns()
in a subclass, you must call this function before removing data from the model's underlying data store.
The parent index corresponds to the parent from which the new columns are removed; first and last are the column numbers of the first and last columns to be removed.
![]() | Specify the first and last column numbers for the span of columns you want to remove from an item in a model. For example, as shown in the diagram, we remove the three columns from column 4 to column 6, so first is 4 and last is 6: itemModel.beginRemoveColumns(null, 4, 6); |
endRemoveColumns()
.
protected final void beginRemoveRows(QModelIndex parent, int first, int last)
When reimplementing removeRows()
in a subclass, you must call this function before removing data from the model's underlying data store.
The parent index corresponds to the parent from which the new rows are removed; first and last are the row numbers of the rows to be removed.
![]() | Specify the first and last row numbers for the span of rows you want to remove from an item in a model. For example, as shown in the diagram, we remove the two rows from row 2 to row 3, so first is 2 and last is 3: itemModel.beginRemoveRows(null, 2, 3); |
endRemoveRows()
.
protected final void changePersistentIndex(QModelIndex from, QModelIndex to)
QPersistentModelIndex
that is equal to the given from model index to the given to model index. If no persistent model index equal to the given from model index was found, nothing is changed.
persistentIndexList()
, and changePersistentIndexList()
.
protected final void changePersistentIndexList(java.util.List from, java.util.List to)
QPersistentModelIndexes
that is equal to the indexes in the given from model index list to the given to model index list. If no persistent model indexes equal to the indexes in the given from model index list was found, nothing is changed.
persistentIndexList()
, and changePersistentIndex()
.
protected final QModelIndex createIndex(int row, int column, int id)
protected final QModelIndex createIndex(int row, int column)
Note that when you are using a QSortFilterProxyModel
its indexes have their own internal pointer. It is not advisable to access the internal pointer in the index outside of the model. Use the data()
function instead.
This function provides a consistent interface that model subclasses must use to create model indexes.
protected final QModelIndex createIndex(int row, int column, QNativePointer data)
Note that when you are using a QSortFilterProxyModel
its indexes have their own internal pointer. It is not advisable to access the internal pointer in the index outside of the model. Use the data()
function instead.
This function provides a consistent interface that model subclasses must use to create model indexes.
protected final void endInsertColumns()
When reimplementing insertColumns()
in a subclass, you must call this function after inserting data into the model's underlying data store.
beginInsertColumns()
.
protected final void endInsertRows()
When reimplementing insertRows()
in a subclass, you must call this function after inserting data into the model's underlying data store.
beginInsertRows()
.
protected final void endRemoveColumns()
When reimplementing removeColumns()
in a subclass, you must call this function after removing data from the model's underlying data store.
beginRemoveColumns()
.
protected final void endRemoveRows()
When reimplementing removeRows()
in a subclass, you must call this function after removing data from the model's underlying data store.
beginRemoveRows()
.
public final boolean hasIndex(int row, int column)
public final boolean hasIndex(int row, int column, QModelIndex parent)
public final boolean insertColumn(int column)
insertColumns()
, insertRow()
, and removeColumn()
.
public final boolean insertColumn(int column, QModelIndex parent)
insertColumns()
, insertRow()
, and removeColumn()
.
public final boolean insertRow(int row)
insertRows()
, insertColumn()
, and removeRow()
.
public final boolean insertRow(int row, QModelIndex parent)
insertRows()
, insertColumn()
, and removeRow()
.
protected final java.util.List persistentIndexList()
public final boolean removeColumn(int column)
removeColumns()
, removeRow()
, and insertColumn()
.
public final boolean removeColumn(int column, QModelIndex parent)
removeColumns()
, removeRow()
, and insertColumn()
.
public final boolean removeRow(int row)
The removeRow()
is a convenience function that calls removeRows()
. The QAbstractItemModel
implementation of removeRows
does nothing.
removeRows()
, removeColumn()
, and insertRow()
.
public final boolean removeRow(int row, QModelIndex parent)
The removeRow()
is a convenience function that calls removeRows()
. The QAbstractItemModel
implementation of removeRows
does nothing.
removeRows()
, removeColumn()
, and insertRow()
.
protected final void reset()
When a model is reset it means that any previous data reported from the model is now invalid and has to be queried for again.
When a model radically changes its data it can sometimes be easier to just call this function rather than emit dataChanged()
to inform other components when the underlying data source, or its structure, has changed.
public final void setSupportedDragActions(Qt.DropAction[] arg__1)
supportedDragActions()
, and Using Drag and Drop with Item Views.
public final void setSupportedDragActions(Qt.DropActions arg__1)
supportedDragActions()
, and Using Drag and Drop with Item Views.
public final QModelIndex sibling(int row, int column, QModelIndex idx)
sibling()
is just a convenience function that finds the item's parent, and uses it to retrieve the index of the child item in the specified row and column.
index()
, QModelIndex::row(), and QModelIndex::column().
public final Qt.DropActions supportedDragActions()
The default implementation returns supportedDropActions()
unless specific values have been set with setSupportedDragActions()
.
supportedDragActions()
is used by QAbstractItemView::startDrag()
as the default values when a drag occurs.
setSupportedDragActions()
, Qt::DropActions, and Using Drag and Drop with Item Views.
public QModelIndex buddy(QModelIndex index)
In the default implementation each item is its own buddy.
public boolean canFetchMore(QModelIndex parent)
The default implementation always returns false.
fetchMore()
.
public final int columnCount()
In most subclasses, the number of columns is independent of the parent. For example:
The following code example is written in c++.
int DomModel::columnCount(const QModelIndex &parent) const { return 3; }Tip: When implementing a table based model,
columnCount()
should return 0 when the parent is valid. rowCount()
.
public abstract int columnCount(QModelIndex parent)
In most subclasses, the number of columns is independent of the parent. For example:
The following code example is written in c++.
int DomModel::columnCount(const QModelIndex &parent) const { return 3; }Tip: When implementing a table based model,
columnCount()
should return 0 when the parent is valid. rowCount()
.
public final java.lang.Object data(QModelIndex index)
Note: If you do not have a value to return, return an emptyQVariant() instead of returning 0.
Qt::ItemDataRole
, setData()
, and headerData()
.
public abstract java.lang.Object data(QModelIndex index, int role)
Note: If you do not have a value to return, return an emptyQVariant() instead of returning 0.
Qt::ItemDataRole
, setData()
, and headerData()
.
public boolean dropMimeData(QMimeData data, Qt.DropAction action, int row, int column, QModelIndex parent)
Although the specified row, column and parent indicate the location of an item in the model where the operation ended, it is the responsibility of the view to provide a suitable location for where the data should be inserted.
For instance, a drop action on an item in a QTreeView
can result in new items either being inserted as children of the item specified by row, column, and parent, or as siblings of the item.
When row and column are -1 it means that it is up to the model to decide where to place the data. This can occur in a tree when data is dropped on a parent. Models will usually append the data to the parent in this case.
Returns true if the dropping was successful otherwise false.
supportedDropActions()
, and Using Drag and Drop with Item Views.
public void fetchMore(QModelIndex parent)
Reimplement this if you have incremental data.
The default implementation does nothing.
canFetchMore()
.
public Qt.ItemFlags flags(QModelIndex index)
The base class implementation returns a combination of flags that enables the item (ItemIsEnabled) and allows it to be selected (ItemIsSelectable).
public final boolean hasChildren()
rowCount()
on the parent to find out the number of children. parent()
, and index()
.
public boolean hasChildren(QModelIndex parent)
rowCount()
on the parent to find out the number of children. parent()
, and index()
.
public final java.lang.Object headerData(int section, Qt.Orientation orientation)
For horizontal headers, the section number corresponds to the column number of items shown beneath it. For vertical headers, the section number typically to the row number of items shown alongside it.
Qt::ItemDataRole
, setHeaderData()
, and QHeaderView
.
public java.lang.Object headerData(int section, Qt.Orientation orientation, int role)
For horizontal headers, the section number corresponds to the column number of items shown beneath it. For vertical headers, the section number typically to the row number of items shown alongside it.
Qt::ItemDataRole
, setHeaderData()
, and QHeaderView
.
public final QModelIndex index(int row, int column)
When reimplementing this function in a subclass, call createIndex()
to generate model indexes that other components can use to refer to items in your model.
createIndex()
.
public abstract QModelIndex index(int row, int column, QModelIndex parent)
When reimplementing this function in a subclass, call createIndex()
to generate model indexes that other components can use to refer to items in your model.
createIndex()
.
public final boolean insertColumns(int column, int count)
If column is 0, the columns are prepended to any existing columns. If column is columnCount()
, the columns are appended to any existing columns. If parent has no children, a single row with count columns is inserted.
Returns true if the columns were successfully inserted; otherwise returns false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support insertions. Alternatively, you can provide you own API for altering the data.
insertRows()
, removeColumns()
, beginInsertColumns()
, and endInsertColumns()
.
public boolean insertColumns(int column, int count, QModelIndex parent)
If column is 0, the columns are prepended to any existing columns. If column is columnCount()
, the columns are appended to any existing columns. If parent has no children, a single row with count columns is inserted.
Returns true if the columns were successfully inserted; otherwise returns false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support insertions. Alternatively, you can provide you own API for altering the data.
insertRows()
, removeColumns()
, beginInsertColumns()
, and endInsertColumns()
.
public final boolean insertRows(int row, int count)
If row is 0, the rows are prepended to any existing rows in the parent. If row is rowCount()
, the rows are appended to any existing rows in the parent. If parent has no children, a single column with count rows is inserted.
Returns true if the rows were successfully inserted; otherwise returns false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support insertions. Alternatively, you can provide you own API for altering the data.
insertColumns()
, removeRows()
, beginInsertRows()
, and endInsertRows()
.
public boolean insertRows(int row, int count, QModelIndex parent)
If row is 0, the rows are prepended to any existing rows in the parent. If row is rowCount()
, the rows are appended to any existing rows in the parent. If parent has no children, a single column with count rows is inserted.
Returns true if the rows were successfully inserted; otherwise returns false.
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support insertions. Alternatively, you can provide you own API for altering the data.
insertColumns()
, removeRows()
, beginInsertRows()
, and endInsertRows()
.
public java.util.SortedMap itemData(QModelIndex index)
Reimplemented this function if you want to extend the default behavior of this function to include custom roles in the map.
setItemData()
, Qt::ItemDataRole
, and data()
.
public final java.util.List match(QModelIndex start, int role, java.lang.Object value, int hits, Qt.MatchFlag[] flags)
The search starts from the start index, and continues until the number of matching data items equals hits, the search reaches the last row, or the search reaches start again, depending on whether MatchWrap is specified in flags. If you want to search for all matching items, use hits = -1.
By default, this function will perform a wrapping, string-based comparison on all items, searching for items that begin with the search term specified by value.
Note: The default implementation of this function only searches columns, This function can be reimplemented to include other search behavior.
public final java.util.List match(QModelIndex start, int role, java.lang.Object value, int hits)
public final java.util.List match(QModelIndex start, int role, java.lang.Object value)
public java.util.List match(QModelIndex start, int role, java.lang.Object value, int hits, Qt.MatchFlags flags)
The search starts from the start index, and continues until the number of matching data items equals hits, the search reaches the last row, or the search reaches start again, depending on whether MatchWrap is specified in flags. If you want to search for all matching items, use hits = -1.
By default, this function will perform a wrapping, string-based comparison on all items, searching for items that begin with the search term specified by value.
Note: The default implementation of this function only searches columns, This function can be reimplemented to include other search behavior.
public QMimeData mimeData(java.util.List indexes)
mimeTypes()
function. If the list of indexes is empty, or there are no supported MIME types, 0 is returned rather than a serialized empty list.
mimeTypes()
, and dropMimeData()
.
public java.util.List mimeTypes()
mimeData()
.
public abstract QModelIndex parent(QModelIndex child)
A common convention used in models that expose tree data structures is that only items in the first column have children. For that case, when reimplementing this function in a subclass the column of the returned QModelIndex would be 0.
Note: When reimplementing this function in a subclass, be careful to avoid calling QModelIndex member functions, such as QModelIndex::parent(), since indexes belonging to your model will simply call your implementation, leading to infinite recursion.
createIndex()
.
public final boolean removeColumns(int column, int count)
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support removing. Alternatively, you can provide you own API for altering the data.
removeColumn()
, removeRows()
, insertColumns()
, beginRemoveColumns()
, and endRemoveColumns()
.
public boolean removeColumns(int column, int count, QModelIndex parent)
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support removing. Alternatively, you can provide you own API for altering the data.
removeColumn()
, removeRows()
, insertColumns()
, beginRemoveColumns()
, and endRemoveColumns()
.
public final boolean removeRows(int row, int count)
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support removing. Alternatively, you can provide you own API for altering the data.
removeRow()
, removeColumns()
, insertColumns()
, beginRemoveRows()
, and endRemoveRows()
.
public boolean removeRows(int row, int count, QModelIndex parent)
The base class implementation does nothing and returns false.
If you implement your own model, you can reimplement this function if you want to support removing. Alternatively, you can provide you own API for altering the data.
removeRow()
, removeColumns()
, insertColumns()
, beginRemoveRows()
, and endRemoveRows()
.
public void revert()
public final int rowCount()
rowCount
is returning the number of children of parent. Tip: When implementing a table based model, rowCount()
should return 0 when the parent is valid.
columnCount()
.
public abstract int rowCount(QModelIndex parent)
rowCount
is returning the number of children of parent. Tip: When implementing a table based model, rowCount()
should return 0 when the parent is valid.
columnCount()
.
public final boolean setData(QModelIndex index, java.lang.Object value)
The dataChanged()
signal should be emitted if the data was successfully set.
The base class implementation returns false. This function and data()
must be reimplemented for editable models. Note that the dataChanged()
signal must be emitted explicitly when reimplementing this function.
Qt::ItemDataRole
, data()
, and itemData()
.
public boolean setData(QModelIndex index, java.lang.Object value, int role)
The dataChanged()
signal should be emitted if the data was successfully set.
The base class implementation returns false. This function and data()
must be reimplemented for editable models. Note that the dataChanged()
signal must be emitted explicitly when reimplementing this function.
Qt::ItemDataRole
, data()
, and itemData()
.
public final boolean setHeaderData(int section, Qt.Orientation orientation, java.lang.Object value)
Note that the headerDataChanged()
signal must be emitted explicitly when reimplementing this function.
Qt::ItemDataRole
, and headerData()
.
public boolean setHeaderData(int section, Qt.Orientation orientation, java.lang.Object value, int role)
Note that the headerDataChanged()
signal must be emitted explicitly when reimplementing this function.
Qt::ItemDataRole
, and headerData()
.
public boolean setItemData(QModelIndex index, java.util.SortedMap roles)
public final void sort(int column)
The base class implementation does nothing.
public void sort(int column, Qt.SortOrder order)
The base class implementation does nothing.
public QSize span(QModelIndex index)
Note: span is not used currently, but will be in the future.
public boolean submit()
Returns false on error, otherwise true.
public Qt.DropActions supportedDropActions()
The default implementation returns Qt::CopyAction
. Reimplement this function if you wish to support additional actions. Note that you must also reimplement the dropMimeData()
function to handle the additional operations.
dropMimeData()
, Qt::DropActions, and Using Drag and Drop with Item Views.
public static QAbstractItemModel fromNativePointer(QNativePointer nativePointer)
public final boolean setData(int row, int col, java.lang.Object value)
public final boolean setData(int row, int col, java.lang.Object value, int role)
Returns true if successful; otherwise, returns false.
public final java.lang.Object data(int row, int col, int role)
public final java.lang.Object data(int row, int col)
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