****要注意创建相应程序的屏幕0100****
在一些情况下，输出的ALV可能用树形结构更容易展现数据之间的相互关联，为了输出ALV-TREE主要用到的是容器类（如CL_GUI_CONTAINER或CL_GUI_CUSTOM_CONTAINER等）和ALV-TREE控制器类CL_GUI_ALV_TREE。
对于类CL_GUI_ALV_TREE,主要用其ADD_NODE的方法添加节点。
下面直接给出仿照SAP示例程序BCALV_TREE_02创建的一个DEMO:
输出目标（汇总可用库存字段/双击节点对应的文件夹图标能展开其子节点）：
*&---------------------------------------------------------------------*
*& Report Z15540_OOALV_TREE
*&---------------------------------------------------------------------*
*&
*&---------------------------------------------------------------------*
REPORT Z15540_OOALV_TREE.
*&---------------------------------------------------------------------*
*&数据对象定义
*&---------------------------------------------------------------------*
DATA:BEGIN OF GS_ALV,
WERKS TYPE MARD-WERKS,
LGORT TYPE MARD-LGORT,
MATNR TYPE MARD-MATNR,
MAKTX TYPE MAKT-MAKTX,
LABST TYPE MARD-LABST,
MEINS TYPE MARA-MEINS,
END OF GS_ALV.
DATA GT_ALV LIKE TABLE OF GS_ALV.
DATA:GS_FCAT TYPE LVC_S_FCAT,
GT_FCAT TYPE LVC_T_FCAT.
DATA:LCL_CONTAINER TYPE REF TO CL_GUI_CONTAINER, "容器类引用变量
LCL_TREE TYPE REF TO CL_GUI_ALV_TREE. "树形ALV控制器引用变量
DATA:OK_CODE TYPE SY-UCOMM, "获取100屏幕触发的功能码
SAVE_CODE TYPE SY-UCOMM.
*&---------------------------------------------------------------------*
*&事件接受类定义
*&---------------------------------------------------------------------*
CLASS LCL_HANDLE DEFINITION.
PUBLIC SECTION.
"定义双击节点事件触发时的处理方法
METHODS HANDLE_NODE_DCLICK
FOR EVENT NODE_DOUBLE_CLICK OF CL_GUI_ALV_TREE
IMPORTING NODE_KEY SENDER.
"其中SENDER这个参数是一个隐式的事件参数，是由ABAP对象运行系统提供，它指向了触发这个事件的实例，可以直接使用它来调用这个实例的方法。
ENDCLASS.
CLASS LCL_HANDLE IMPLEMENTATION.
"定义处理方法的具体实施
METHOD HANDLE_NODE_DCLICK.
DATA: LT_CHILDREN TYPE LVC_T_NKEY.
*检查被点击的NODE几点下面有无子节点，有则展开节点。
CALL METHOD SENDER->GET_CHILDREN
EXPORTING
I_NODE_KEY = NODE_KEY
IMPORTING
ET_CHILDREN = LT_CHILDREN.
IF NOT LT_CHILDREN IS INITIAL.
CALL METHOD SENDER->EXPAND_NODE
EXPORTING
I_NODE_KEY = NODE_KEY
I_LEVEL_COUNT = 2.
ENDIF.
ENDMETHOD.
ENDCLASS.
START-OF-SELECTION.
CALL SCREEN 100.
*&---------------------------------------------------------------------*
*& Module STATUS_0100 OUTPUT
*&---------------------------------------------------------------------*
*&
*&---------------------------------------------------------------------*
MODULE STATUS_0100 OUTPUT.
SET PF-STATUS 'MAIN100'.
SET TITLEBAR 'TITLE'.
IF LCL_TREE IS INITIAL.
PERFORM INIT_TREE.
CALL METHOD CL_GUI_CFW=>FLUSH
EXCEPTIONS
CNTL_SYSTEM_ERROR = 1
CNTL_ERROR = 2.
IF SY-SUBRC NE 0.
CALL FUNCTION 'POPUP_TO_INFORM'
EXPORTING
TITEL = 'Automation Queue failure'
TXT1 = 'Internal error:'
TXT2 = 'A method in the automation queue'
TXT3 = 'caused a failure.'.
ENDIF.
ENDIF.
ENDMODULE.
*&---------------------------------------------------------------------*
*& Form INIT_TREE
*&---------------------------------------------------------------------*
*& text
*&---------------------------------------------------------------------*
*& --> p1 text
*& <-- p2 text
*&---------------------------------------------------------------------*
FORM INIT_TREE .
"1.实例化容器对象
LCL_CONTAINER = CL_GUI_CONTAINER=>SCREEN0.
"2.实例化TREE控制器
CREATE OBJECT LCL_TREE
EXPORTING
PARENT = LCL_CONTAINER "绑定容器
NODE_SELECTION_MODE = CL_GUI_COLUMN_TREE=>NODE_SEL_MODE_SINGLE
ITEM_SELECTION = 'X'
NO_HTML_HEADER = 'X'
NO_TOOLBAR = ''
EXCEPTIONS
CNTL_ERROR = 1
CNTL_SYSTEM_ERROR = 2
CREATE_ERROR = 3
LIFETIME_ERROR = 4
ILLEGAL_NODE_SELECTION_MODE = 5
FAILED = 6
ILLEGAL_COLUMN_NAME = 7.
IF SY-SUBRC <> 0.
MESSAGE E208(00) WITH '实例化ALV TREE控制器失败！'. "
ENDIF.
"3.设置NODE描述字段信息
DATA L_HIERARCHY_HEADER TYPE TREEV_HHDR.
PERFORM BUILD_HIERARCHY_HEADER CHANGING L_HIERARCHY_HEADER.
"4.设置ALV字段
PERFORM FRM_FILLFIELD USING: 'WERKS' '工厂',
'LGORT' '仓库',
'MATNR' '物料号',
'MAKTX' '物料描述',
'LABST' '非限制使用库存',
'MEINS' '数量单位'.
"5设置ALV显示字段
CALL METHOD LCL_TREE->SET_TABLE_FOR_FIRST_DISPLAY
EXPORTING
IS_HIERARCHY_HEADER = L_HIERARCHY_HEADER
CHANGING
IT_FIELDCATALOG = GT_FCAT
IT_OUTTAB = GT_ALV. "此表必须一直为空，且为全局变量
"6.设置根节点，填充叶节点数据
PERFORM CREATE_HIERARCHY.
"7.注册事件
PERFORM REGISTER_EVENTS.
* 更新汇总字段
CALL METHOD LCL_TREE->UPDATE_CALCULATIONS.
*前端显示数据
CALL METHOD LCL_TREE->FRONTEND_UPDATE.
ENDFORM.
*&---------------------------------------------------------------------*
*& Form build_hierarchy_header
*&---------------------------------------------------------------------*
* build hierarchy-header-information
*----------------------------------------------------------------------*
* -->P_L_HIERARCHY_HEADER strucxture for hierarchy-header
*----------------------------------------------------------------------*
FORM BUILD_HIERARCHY_HEADER CHANGING
P_HIERARCHY_HEADER TYPE TREEV_HHDR.
P_HIERARCHY_HEADER-HEADING = '工厂/仓库'.
P_HIERARCHY_HEADER-TOOLTIP = '节点依据'.
P_HIERARCHY_HEADER-WIDTH = 50.
P_HIERARCHY_HEADER-WIDTH_PIX = ''.
ENDFORM.
*&---------------------------------------------------------------------*
*& Form FRM_FILLFIELD
*&---------------------------------------------------------------------*
*& text
*&---------------------------------------------------------------------*
*& --> P_
*& --> P_
*&---------------------------------------------------------------------*
FORM FRM_FILLFIELD USING P_FIELDNAME TYPE LVC_FNAME
P_COLTEXT TYPE LVC_TXTCOL.
CLEAR GS_FCAT.
GS_FCAT-FIELDNAME = P_FIELDNAME.
GS_FCAT-COLTEXT = P_COLTEXT.
IF P_FIELDNAME = 'WERKS' OR P_FIELDNAME = 'LGORT' OR P_FIELDNAME = 'MATNR' .
GS_FCAT-NO_OUT = 'X'."隐藏右侧输出的MATNR/WERKS/LGORT字段
ELSEIF P_FIELDNAME = 'LABST'.
GS_FCAT-QFIELDNAME = 'MEINS'.
GS_FCAT-DO_SUM = 'X'."汇总可用库存字段
GS_FCAT-H_FTYPE = 'SUM'.
GS_FCAT-REF_FIELD = 'LABST'.
GS_FCAT-REF_TABLE = 'MARD'.
GS_FCAT-OUTPUTLEN = '30'.
ELSEIF P_FIELDNAME = 'MAKTX'.
GS_FCAT-OUTPUTLEN = '30'.
ENDIF.
APPEND GS_FCAT TO GT_FCAT.
ENDFORM.
*&---------------------------------------------------------------------*
*& Form CREATE_HIERARCHY
*&---------------------------------------------------------------------*
*& text
*&---------------------------------------------------------------------*
*& --> p1 text
*& <-- p2 text
*&---------------------------------------------------------------------*
FORM CREATE_HIERARCHY .
DATA: LS_NODE LIKE GS_ALV,
LS_ALV LIKE GS_ALV,
LT_ALV LIKE TABLE OF GS_ALV,
L_LAST_WERKS TYPE MARD-WERKS,
L_LAST_LGORT TYPE MARD-LGORT.
DATA: L_WERKS_KEY TYPE LVC_NKEY,
L_LGORT_KEY TYPE LVC_NKEY,
L_LAST_KEY TYPE LVC_NKEY,
L_TOP_KEY TYPE LVC_NKEY.
DATA L_NODE_TEXT TYPE LVC_VALUE.
SELECT D~MATNR,
D~WERKS,
D~LGORT,
D~LABST,
A~MEINS,
T~MAKTX
INTO CORRESPONDING FIELDS OF TABLE @LT_ALV UP TO 200 ROWS
FROM MARD AS D INNER JOIN MARA AS A
ON D~MATNR = A~MATNR
LEFT OUTER JOIN MAKT AS T
ON D~MATNR = T~MATNR
WHERE T~SPRAS = @SY-LANGU.
SORT LT_ALV BY WERKS LGORT.
"添加祖节点
CALL METHOD LCL_TREE->ADD_NODE
EXPORTING
I_RELAT_NODE_KEY = ''
I_RELATIONSHIP = CL_GUI_COLUMN_TREE=>RELAT_LAST_CHILD
I_NODE_TEXT = '可用库存'
IMPORTING
E_NEW_NODE_KEY = L_TOP_KEY. "祖节点标识
"按照工厂->仓库层次设置节点，设置”叶片“，填充"叶片"数据
LOOP AT LT_ALV INTO LS_ALV.
"设置工厂节点
IF L_LAST_WERKS NE LS_ALV-WERKS.
L_LAST_WERKS = LS_ALV-WERKS.
"若此次循环到的工厂与上一次不相同，则创造新的工厂节点
"ADD NODE
CLEAR L_NODE_TEXT.
L_NODE_TEXT = LS_ALV-WERKS.
CALL METHOD LCL_TREE->ADD_NODE
EXPORTING
I_RELAT_NODE_KEY = L_TOP_KEY "处于祖节点之下
I_RELATIONSHIP = CL_GUI_COLUMN_TREE=>RELAT_LAST_CHILD
I_NODE_TEXT = L_NODE_TEXT
IS_OUTTAB_LINE = LS_NODE
IMPORTING
E_NEW_NODE_KEY = L_WERKS_KEY. "工厂节点标识
CLEAR L_LAST_LGORT."当创建新的工厂节点时，清空上一个库存节点
ENDIF.
"设置库存节点
IF L_LAST_LGORT NE LS_ALV-LGORT.
L_LAST_LGORT = LS_ALV-LGORT.
"若此次循环到的库存点点与上一次不相同，则创造新的库存节点
"ADD NODE
CLEAR L_NODE_TEXT.
L_NODE_TEXT = LS_ALV-LGORT.
CALL METHOD LCL_TREE->ADD_NODE
EXPORTING
I_RELAT_NODE_KEY = L_WERKS_KEY "处于工厂节点之下
I_RELATIONSHIP = CL_GUI_COLUMN_TREE=>RELAT_LAST_CHILD
I_NODE_TEXT = L_NODE_TEXT
IS_OUTTAB_LINE = LS_NODE
IMPORTING
E_NEW_NODE_KEY = L_LGORT_KEY. "工厂节点标识
ENDIF.
"设置”叶片“，填充"叶片"数据
CLEAR L_NODE_TEXT.
L_NODE_TEXT = LS_ALV-MATNR.
CALL METHOD LCL_TREE->ADD_NODE
EXPORTING
I_RELAT_NODE_KEY = L_LGORT_KEY "处于库存节点之下
I_RELATIONSHIP = CL_GUI_COLUMN_TREE=>RELAT_LAST_CHILD
I_NODE_TEXT = L_NODE_TEXT
IS_OUTTAB_LINE = LS_ALV "有数据
IMPORTING
E_NEW_NODE_KEY = L_LAST_KEY. "工厂节点标识
ENDLOOP.
ENDFORM.
*&---------------------------------------------------------------------*
*& Form REGISTER_EVENTS
*&---------------------------------------------------------------------*
*& text
*&---------------------------------------------------------------------*
*& --> p1 text
*& <-- p2 text
*&---------------------------------------------------------------------*
FORM REGISTER_EVENTS .
"注册前端后后端事件
DATA: LT_EVENTS TYPE CNTL_SIMPLE_EVENTS,
L_EVENT TYPE CNTL_SIMPLE_EVENT,
L_EVENT_RECEIVER TYPE REF TO LCL_HANDLE.
*1。获取已注册的前端事件
CALL METHOD LCL_TREE->GET_REGISTERED_EVENTS
IMPORTING
EVENTS = LT_EVENTS.
"2.添加前端双击时间
L_EVENT-EVENTID = CL_GUI_COLUMN_TREE=>EVENTID_NODE_DOUBLE_CLICK.
APPEND L_EVENT TO LT_EVENTS.
*3.重新设置前端注册时间
CALL METHOD LCL_TREE->SET_REGISTERED_EVENTS
EXPORTING
EVENTS = LT_EVENTS
EXCEPTIONS
CNTL_ERROR = 1
CNTL_SYSTEM_ERROR = 2
ILLEGAL_EVENT_COMBINATION = 3.
IF SY-SUBRC <> 0.
MESSAGE E208(00) WITH '注册前端事件失败！'. "#EC NOTEXT
ENDIF.
*--------------------
"4.注册后端事件
CREATE OBJECT L_EVENT_RECEIVER.
SET HANDLER L_EVENT_RECEIVER->HANDLE_NODE_DCLICK FOR LCL_TREE.
ENDFORM.
*&---------------------------------------------------------------------*
*& Module USER_COMMAND_0100 INPUT
*&---------------------------------------------------------------------*
* text
*----------------------------------------------------------------------*
MODULE USER_COMMAND_0100 INPUT.
SAVE_CODE = OK_CODE.
CLEAR OK_CODE.
CASE SAVE_CODE.
WHEN 'EXIT' OR 'BACK' OR 'CANC'.
"释放容器，退出程序
CALL METHOD LCL_CONTAINER->FREE.
LEAVE PROGRAM.
WHEN OTHERS.
"为正确调用工具栏按钮功能，必须调用该方法
CALL METHOD CL_GUI_CFW=>DISPATCH.
ENDCASE.
CALL METHOD CL_GUI_CFW=>FLUSH.
ENDMODULE.
本文转载自：https://www.cnblogs.com/jianglaizhen/p/8870859.html