com.softwareag.mobile.runtime.toolkit.delegates

Interface IListDatasource

All Superinterfaces:

IDatasource

All Known Implementing Classes:

AbstractListDatasource, JSONDatasource

public interface IListDatasource
extends IDatasource

IListDatasource extends IDatasource for management of list (index) based data models. This is the base used for ListView objects. Each index in the IListDatasource represents one row in the ListView.

Currently JSONDatasource is the only available implementation. You can use AbstractListDatasource as abstract base implementation to extend for your own needs.

Version:

9.7.0.0000-0116

Method Summary

Methods

Modifier and Type	Method and Description
void	addElement(java.lang.Object object) Add a new object to the data model.
void	addElementAtIndex(java.lang.Object object, int index) Insert a new object to the data model at the given row index.
void	addElements(java.util.Vector objects) Add multiple new objects to the data model.
IComparator	getComparator() Use this method to get the current IComparator used by the ListView.
java.lang.Object	getElementAtIndex(int index) Call this method to get the object of the data model at a given index.
java.util.Vector	getElements() Call this method to get all objects in the data model managed by this datasource.
DatasourceException	getException() Use this method to get the last exception that has been caught while reloading the datasource.
java.lang.Object	getExpressionValue(java.lang.String relativeExpression, int elementIndex) This method to get the object of the data model using an expression that is relative to on object in the data model with the given row index.
java.util.Vector	getFilteredElements() Returns all elements matching the getFilterExpression().
java.lang.String	getFilterExpression() Returns the filter expression currently used.
int	getNumberOfElements() Call this method to get the total number of objects in the data model managed by this datasource.
java.lang.Object	getSelectedElement() Returns the currently selected object of the ListView or null if no object was set as selected.
boolean	hasException() Use this method to check for exceptions that might have been caught while reloading the datasource.
boolean	isFilteredElement(java.lang.Object object) Returns true if the given object matches the filter for this datasource returned by getFilterExpression().
void	reloadElements() Use to reload the objects managed by the datasource.
void	removeAllElements() Removes all objects from the data model.
void	removeElement(java.lang.Object object) Remove the given object from the data model.
void	removeElementAtIndex(int index) Remove the object at the given index of the data model.
void	resort() Call this method to manually resort the contents of the data model.
void	setComparator(IComparator comparator) Use this method to set a IComparator implementation to be used when sorting or resorting the data model represention in the ListView.
void	setElements(java.util.Vector objects) Set the elements managed by the datasource to the given Vector of objects.
void	setFilterExpression(java.lang.String filter) Use this method to set a filter expression and enable filtering for the datasource.
void	setSelectedElement(java.lang.Object object) Set the object selected by the ListView.

Methods inherited from interface com.softwareag.mobile.runtime.toolkit.delegates.IDatasource

getExpressionValue

Method Detail

getExpressionValue

java.lang.Object getExpressionValue(java.lang.String relativeExpression,
                                  int elementIndex)
                                    throws java.lang.Exception

This method to get the object of the data model using an expression that is relative to on object in the data model with the given row index. An expression can be any String an IDatasource implementation uses to reference an object.

Parameters:

expression - String that references an object in the data model

elementIndex - the index of the object to be used to evaluate the given expression

Returns:

the object for the given expression or null if there was no object

Throws:

java.lang.Exception - if an error occured evaluating the given expression

reloadElements

void reloadElements()

Use to reload the objects managed by the datasource.

getNumberOfElements

int getNumberOfElements()

Call this method to get the total number of objects in the data model managed by this datasource.

Returns:

the total number of objects

getElements

java.util.Vector getElements()

Call this method to get all objects in the data model managed by this datasource. Changing the Vector returned will not change the contents of the data model.

Returns:

all objects in the data model

getFilteredElements

java.util.Vector getFilteredElements()

Returns all elements matching the getFilterExpression(). If no filter is set, all elements will be returned. If the datasource content is changed, on the next call of this method the filter is applied first before returning the result.

Returns:

the elements matching the getFilterExpression() or all elements if getFilterExpression() returns null

isFilteredElement

boolean isFilteredElement(java.lang.Object object)

Returns true if the given object matches the filter for this datasource returned by getFilterExpression(). You need to implement this method specifically for your datasource and the object types managed.

Parameters:

object - the object to test if it matches getFilterExpression()

Returns:

true if the filter returned by getFilterExpression() matches the object, false if it does not

getElementAtIndex

java.lang.Object getElementAtIndex(int index)

Call this method to get the object of the data model at a given index.

Parameters:

index - the row index of the object starting at 0.

Returns:

the object at the given row index

setElements

void setElements(java.util.Vector objects)

Set the elements managed by the datasource to the given Vector of objects. This overwrites the current elements.

Parameters:

the - objects to be managed by the datasource

setFilterExpression

void setFilterExpression(java.lang.String filter)

Use this method to set a filter expression and enable filtering for the datasource. If filtering is enabled, only the objects matching the filter expression will be returned by getNumberOfElements(), getElements(), etc. You typically use filter to implement searches in a . An expression can be any String an IListDatasource implementation uses to reference an object.

Parameters:

filter - the filter string the datasource uses to filter it's content

getFilterExpression

java.lang.String getFilterExpression()

Returns the filter expression currently used. If no filter expression is used, null will be returned

Returns:

the filter expression currently used

removeElementAtIndex

void removeElementAtIndex(int index)

Remove the object at the given index of the data model.

Parameters:

index - the row index of the object to be removed

removeElement

void removeElement(java.lang.Object object)

Remove the given object from the data model.

Parameters:

object - the object to be removed

removeAllElements

void removeAllElements()

Removes all objects from the data model.

addElement

void addElement(java.lang.Object object)

Add a new object to the data model. Objects are added to the end.

Parameters:

object - the object to be added to the data model

addElementAtIndex

void addElementAtIndex(java.lang.Object object,
                     int index)

Insert a new object to the data model at the given row index.

Parameters:

object - the object to be added to the data model

index - the index to add the object at

addElements

void addElements(java.util.Vector objects)

Add multiple new objects to the data model. Objects are added to the end.

Parameters:

objects - a Vector of objects to be added

setSelectedElement

void setSelectedElement(java.lang.Object object)

Set the object selected by the ListView.

Parameters:

object - the selected object

getSelectedElement

java.lang.Object getSelectedElement()

Returns the currently selected object of the ListView or null if no object was set as selected.

Returns:

the object selected by the ListView

setComparator

void setComparator(IComparator comparator)

Use this method to set a IComparator implementation to be used when sorting or resorting the data model represention in the ListView.

Parameters:

comparator - the comparator implementation used for sorting

getComparator

IComparator getComparator()

Use this method to get the current IComparator used by the ListView.

Returns:

the IComparator implementation currently used or null if sorting is disabled.

resort

void resort()

Call this method to manually resort the contents of the data model. Changing the order of objects by resorting requires a ListView.reload() to reflect the changes in the user interface.

hasException

boolean hasException()

Use this method to check for exceptions that might have been caught while reloading the datasource.

Returns:

true if there was an exception when initializing the elements.

getException

DatasourceException getException()

Use this method to get the last exception that has been caught while reloading the datasource.

Returns:

the last exception.