controller and context programming

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SAP AG 2005, Title of Presentation / Speaker Name / #

The Context At Runtime

Understand the controller methods that are availableto you for application coding

The Context API

Contents:

Controller and Context Programming


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After completing this topic, you will be able to:

Understand how to access nodes and attributes inthe context using the context API.

The Context API: Topic Objectives


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Common Controller Features:Standard Controller Hook Methods

Controller

Implementation

StandardHook

Methods

Instance

Methods

Context

Root Node

RequiredControllers

ControllerInterface

Other WDControllers

CustomController

BusinessLogic

(Models)

Created by explicit declaration or coding Created by the Web Dynpro Framework (WDF)

ComponentUsage

Other WDComponents


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Standard Hook Methods for all controllers

All controllers have these two standard hook methods.

The method will only be called during the controllers lifecycle if theycontain coding.

method WDDOINIT.endmethod.

method WDDOEXIT.endmethod.


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Common Controller Features: Controller Instance Methods

Controller

Implementation

StandardHook

Methods

Instance

Methods

Context

Root Node

RequiredControllers

ControllerInterface

Other WDControllers

CustomController

BusinessLogic

(Models)

Created by explicit declaration or coding Created by the Web Dynpro Framework (WDF)

ComponentUsage

Other WDComponents


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Controller Attributes and Utility methods

Attributes for the controller can be created (public or private)

Arbitrary methods can be created - .


7/21 SAP AG 2005, Title of Presentation / Speaker Name / #

Standard Controller Attributes WD_CONTEXT and WD_THIS

WD_CONTEXT and WD_THIS

present in any WD controller (excepted interface and interface viewcontroller).

WD_THIS - self reference of the local interface, type depends on the

controller type. WD_CONTEXT - reference to the context of associated controller.



Standard Controller Attribute WD_COMP_CONTROLLER

WD_COMP_CONTROLLER

present in any WD controller.

reference to the component controller with access to all public methodsand attributes.

Attribute will automatically assigned to all view controllers when a viewis created.

For all other controller the WD_COMP_CONTROLLER attribute willbe assigned, when the properties of the controller the componentcontroller is used.



Standard Hook Methods Component Controller

Note: Only a component controller has these hook methods.

WDDOBEFORENAVIGATIONIt is executed before the navigation stack is processed

WDDOPOSTPROCESSING

Data from multiple components can be validated before the next step isexecute



Access to Attribute of Node Element I

Flights..nCARRID

CONNID2CARRID

CONNID1CARRID

CONNID

Context Root

0Default

Element

data: Node_Flights type ref to If_Wd_Context_Node.

* navigate from to via lead selectionNode_Flights = wd_Context->get_Child_Node( Name = `FLIGHTS` ).

* @TODO handle not set lead selectionif ( Node_Flights is initial ).endif.

Note: Node and attribute

names must beused in upper case



Access to Attribute of Node Element II

Flights..nCARRID

CONNID2CARRID

CONNID1CARRID

CONNID

Context Root

0Default

Element

data: Node_Flights type ref to If_Wd_Context_Node,Elem_Flights type ref to If_Wd_Context_Element.


* get element via lead selectionElem_Flights = Node_Flights->get_Element( ).

* @TODO handle not set lead selectionif ( Elem_Flights is initial ).endif.



Access to Attribute of Node Element III

Flights..nCARRID

CONNID2CARRID

CONNID1CARRID

CONNID

Context Root

0Default

Element

data: Node_Flights type ref to If_Wd_Context_Node,Elem_Flights type ref to If_Wd_Context_Element,Item_CARRID like Stru_Flights-CARRID.


* get element via lead selection

Elem_Flights = Node_Flights->get_Element( ).

* get single attributeElem_Flights->get_Attribute(exportingName = `CARRID`importing

Value = Item_Carrid ).



Access to all Static Attributes of a Node Element

Flights..nCARRID

CONNID2CARRID

CONNID1CARRID

CONNID

Context Root

0Default

Element

data: Node_Flights type ref to If_Wd_Context_Node,Elem_Flights type ref to If_Wd_Context_Element,Stru_Flights type If_Componentcontroller=>Element_Flights.


* get element via lead selection

Elem_Flights = Node_Flights->get_Element( ).

* get all declared attributesElem_Flights->get_Static_Attributes(importingStatic_Attributes = Stru_Flights ).



Access to all Elements of a Node

Flights..nCARRID

CONNID2CARRID

CONNID1CARRID

CONNID

Context Root

0Default

Element

data: Node_Flights type ref to If_Wd_Context_Node,Elem_Flights type ref to If_Wd_Context_Element,lt_Flights type If_Main_View=>Elements_Flights .


* @TODO handle not set lead selection

if ( Node_Flights is initial ).endif.

* get all node elementNode_Flights->GET_STATIC_ATTRIBUTES_TABLE( importingtable = lt_Flights ).

Itab



Binding of an Element to a Node I

FLIGHTSContext Root

0Default

Element

data:Node_Flights type ref to If_Wd_Context_Node.

* navigate from to via lead selectionnode_flights = wd_context->get_child_node( Name = 'FLIGHTS' ).



Binding of an Element to a Node II

FLIGHTSContext Root

0Default

Element

data:Node_Flights type ref to If_Wd_Context_Node,First_flight_Elem type ref to If_Wd_Context_Element.


* create new element for node FLIGHTS

First_flight_Elem = Node_Flights->create_element( ).


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Binding of an Element to a Node III

FLIGHTSContext Root

0Default

Element

CARRID

CONNID



* create new element for node FLIGHTS

First_flight_Elem = Node_Flights->create_element( ).

* set attributesFirst_flight_Elem->set_attribute( name = 'CARRID' value = 'LH' ).First_flight_Elem->set_attribute( name = 'CONNID' value = '400' ).


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FLIGHTSContext Root

0Default

Element

CARRID

CONNID

1

Binding of an Element to a Node IV



* create new element for node FLIGHTSFirst_flight_Elem = Node_Flights->create_element( ).

* set attributesFirst_flight_Elem->set_attribute( name = 'CARRID' value = 'LH' ).First_flight_Elem->set_attribute( name = 'CONNID' value = '400' ).

* bind first element to node

Node_Flights->bind_element( new_item = First_flight_ElemSET_INITIAL_ELEMENTS = abap_false ).


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Static Attributes and Binding of a Element to a Node

data:Node_Flights type ref to If_Wd_Context_Node,Stru_flights type If_Componentcontroller=>Element_flights.


* set values to node->attributesStru_flights-carrid = 'AA'.Stru_flights-connid = '017'.

* bind new element to nodeNode_flights->bind_structure( new_item = Stru_flights

SET_INITIAL_ELEMENTS = abap_false ).


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FLIGHTSContext Root

0Default

Element

Binding of a Table to a Node

data:Node_Flights type ref to If_Wd_Context_Node,

lt_flights type If_Componentcontroller=>Elements_flights,Stru_flights like line of lt_flights.

* append values to local tableStru_flights-carrid = 'LH'.Stru_flights-connid = '400'.append Stru_flights to lt_flights.

Stru_flights-carrid = 'AA'.Stru_flights-connid = '017'.append Stru_flights to lt_flights.

* get node referenceNode_Flights = wd_context->get_child_node( 'FLIGHTS' ).

* bind local tableNode_Flights->bind_table( lt_flights ).

CARRID

CONNID

1

ItabCARRID


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SAP AG 2005 Titl f P t ti / S k N / #

You should now be able to:

Understand how to access nodes and attributes inthe context using the context API

Controller and Context Programming: Unit Summary

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controller and context programming