Grid List - Drag and Drop

The class

" @keywords gridlist grid list sap.f drag drop panel toolbar title draginfo griddropinfo gridboxlayout
" @summary This sample represents GridList with enabled Drag and Drop functionality.
" @origin sap.f.sample.GridListDragAndDrop - https://sdk.openui5.org/entity/sap.f.GridList/sample/sap.f.sample.GridListDragAndDrop (status: reviewed - read against the original, not run)
CLASS z2ui5_cl_smpc_app_148 DEFINITION PUBLIC.

  PUBLIC SECTION.
    INTERFACES z2ui5_if_app.

    TYPES:
      BEGIN OF ty_item,
        title     TYPE string,
        subtitle  TYPE string,
        counter   TYPE i,
        highlight TYPE string,
        type      TYPE string,
        unread    TYPE abap_bool,
        busy      TYPE abap_bool,
      END OF ty_item.
    DATA t_items TYPE STANDARD TABLE OF ty_item WITH EMPTY KEY.

  PROTECTED SECTION.
    DATA client TYPE REF TO z2ui5_if_client.

    METHODS view_display.
    METHODS on_event.
    METHODS model_init.

  PRIVATE SECTION.
ENDCLASS.


CLASS z2ui5_cl_smpc_app_148 IMPLEMENTATION.

  METHOD z2ui5_if_app~main.

    me->client = client.
    IF client->check_on_init( ).
      model_init( ).
      view_display( ).
    ELSEIF client->check_on_navigated( ).
      view_display( ).
    ELSEIF client->check_on_event( ).
      on_event( ).
    ENDIF.

  ENDMETHOD.


  METHOD view_display.

    DATA(view) = z2ui5_cl_ui5_view_builder=>factory( ).

    " the drop carries the two row indices and the insert position as client-side
    " resolved $-args (CAPABILITIES "Drag & drop reorder"); on_event reorders the
    " ABAP table with exactly the original controller's splice arithmetic
    view->ele( n = `View` ns = `mvc`
        )->a( n = `xmlns`         v = `sap.m`
        )->a( n = `xmlns:mvc`     v = `sap.ui.core.mvc`
        )->a( n = `xmlns:grid`    v = `sap.ui.layout.cssgrid`
        )->a( n = `xmlns:f`       v = `sap.f`
        )->a( n = `xmlns:dnd`     v = `sap.ui.core.dnd`
        )->a( n = `xmlns:dndgrid` v = `sap.f.dnd`

        )->ele( `Panel`
            )->a( n = `id`               v = `panelForGridList`
            )->a( n = `backgroundDesign` v = `Transparent`

            )->ele( `headerToolbar`
                )->ele( `Toolbar`
                    )->a( n = `height` v = `3rem`
                    )->tag( `Title`
                        )->a( n = `text` v = `Grid List with Drag and Drop`

                )->end(
            )->end(

            )->ele( n = `GridList` ns = `f`
                )->a( n = `id`         v = `gridList`
                )->a( n = `headerText` v = `GridList header`
                )->a( n = `items`      v = client->_bind( t_items )

                )->ele( n = `dragDropConfig` ns = `f`
                    )->tag( n = `DragInfo` ns = `dnd`
                        )->a( n = `sourceAggregation` v = `items`
                    )->tag( n = `GridDropInfo` ns = `dndgrid`
                        )->a( n = `targetAggregation` v = `items`
                        )->a( n = `dropPosition`      v = `Between`
                        )->a( n = `dropLayout`        v = `Horizontal`
                        )->a( n = `drop`              v = client->_event( val   = `DROP`
                                                                          t_arg = VALUE #(
                                                                            ( `${$parameters>/draggedControl/oParent}.indexOfItem(${$parameters>/draggedControl})` )
                                                                            ( `${$parameters>/droppedControl/oParent}.indexOfItem(${$parameters>/droppedControl})` )
                                                                            ( `${$parameters>/dropPosition}` ) ) )

                )->end(

                )->ele( n = `customLayout` ns = `f`
                    )->tag( n = `GridBoxLayout` ns = `grid`
                        )->a( n = `boxMinWidth` v = `17rem`

                )->end(

                )->ele( n = `GridListItem` ns = `f`
                    )->a( n = `counter`   v = `{COUNTER}`
                    )->a( n = `highlight` v = `{HIGHLIGHT}`
                    )->a( n = `type`      v = `{TYPE}`
                    )->a( n = `unread`    v = `{UNREAD}`
                    )->ele( `VBox`
                        )->a( n = `height` v = `100%`
                        )->ele( `VBox`
                            )->a( n = `class` v = `sapUiSmallMargin`
                            )->ele( `layoutData`
                                )->tag( `FlexItemData`
                                    )->a( n = `growFactor`   v = `1`
                                    )->a( n = `shrinkFactor` v = `0`

                            )->end(
                            )->tag( `Title`
                                )->a( n = `text`     v = `{TITLE}`
                                )->a( n = `wrapping` v = `true`
                            )->tag( `Label`
                                )->a( n = `text`     v = `{SUBTITLE}`
                                )->a( n = `wrapping` v = `true` ).

    client->view_display( view->stringify( ) ).

  ENDMETHOD.


  METHOD on_event.

    IF client->get_event( ) = `DROP`.
      " onDrop 1:1 - the client indices are 0-based, ABAP rows 1-based. Both
      " arrive from the frontend, so they are range-checked before they are
      " used as a table index: JS would splice a nonsense index harmlessly,
      " ABAP would dump on the read
      DATA(drag_pos) = CONV i( client->get_event_arg( ) ).
      DATA(drop_pos) = CONV i( client->get_event_arg( 2 ) ).
      DATA(position) = client->get_event_arg( 3 ).

      IF drag_pos < 0 OR drag_pos >= lines( t_items ) OR drop_pos < 0 OR drop_pos >= lines( t_items ).
        RETURN.
      ENDIF.

      DATA(item) = t_items[ drag_pos + 1 ].
      DELETE t_items INDEX drag_pos + 1.

      IF drag_pos < drop_pos.
        drop_pos = drop_pos - 1.
      ENDIF.

      " the original is two Array.splice calls, and splice CLAMPS a start index
      " past the end - it appends. ABAP does not: INSERT ... INDEX beyond
      " lines + 1 sets sy-subrc = 4 and inserts nothing, so the row deleted a
      " moment ago would be gone. Reachable: GridDragOver falls back to the LAST
      " item with "After" when the pointer is over no item at all, which can be
      " the dragged one, giving drag_pos = drop_pos = lines - 1
      DATA(insert_at) = COND i( WHEN position = `Before` THEN drop_pos + 1 ELSE drop_pos + 2 ).
      IF insert_at > lines( t_items ) + 1.
        insert_at = lines( t_items ) + 1.
      ENDIF.
      INSERT item INTO t_items INDEX insert_at.
    ENDIF.

  ENDMETHOD.


  METHOD model_init.

    " 27 items inlined from model/data.json; absent enum fields defaulted to
    " their UI5 values (highlight None, type Inactive) so the bound properties
    " stay valid, matching the original's undefined-renders-as-default.
    t_items = VALUE #(
      ( title = `Box title 1` subtitle = `Subtitle 1` counter = 5 highlight = `Error` type = `Active` unread = abap_true busy = abap_false )
      ( title = `Box title 2` subtitle = `Subtitle 2` counter = 15 highlight = `Warning` type = `Active` unread = abap_false busy = abap_false )
      ( title = `Box title 3` subtitle = `Subtitle 3` counter = 15734 highlight = `None` type = `Inactive` unread = abap_false busy = abap_true )
      ( title = `Box title 4` subtitle = `Subtitle 4` counter = 2 highlight = `None` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title 5` subtitle = `Subtitle 5` counter = 1 highlight = `Warning` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title 6 Box title Box title Box title Box title Box title` subtitle = `Subtitle 6` counter = 5 highlight = `None` type = `Active` unread = abap_false busy = abap_false )
      ( title = `Very long Box title that should wrap 7` subtitle = `This is a long subtitle 7` counter = 5 highlight = `Error` type = `DetailAndActive` unread = abap_false busy = abap_false )
      ( title = `Box title B 8` subtitle = `Subtitle 8` counter = 0 highlight = `None` type = `Navigation` unread = abap_false busy = abap_false )
      ( title = `Box title B 9 Box title B  Box title B 9 Box title B 9Box title B 9title B 9 Box title B 9Box title B` subtitle = `Subtitle 9` counter = 0 highlight = `Success` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title B 10` subtitle = `Subtitle 10` counter = 0 highlight = `None` type = `Active` unread = abap_false busy = abap_false )
      ( title = `Box title B 11` subtitle = `Subtitle 11` counter = 0 highlight = `None` type = `Active` unread = abap_false busy = abap_false )
      ( title = `Box title B 12` subtitle = `Subtitle 12` counter = 0 highlight = `Information` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title 13` subtitle = `Subtitle 13` counter = 5 highlight = `None` type = `Navigation` unread = abap_false busy = abap_false )
      ( title = `Box title 14` subtitle = `Subtitle 14` counter = 0 highlight = `Success` type = `DetailAndActive` unread = abap_false busy = abap_false )
      ( title = `Box title 15` subtitle = `Subtitle 15` counter = 0 highlight = `None` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title 16` subtitle = `Subtitle 16` counter = 37412578 highlight = `None` type = `Navigation` unread = abap_false busy = abap_false )
      ( title = `Box title 17` subtitle = `Subtitle 17` counter = 0 highlight = `Information` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title 18` subtitle = `Subtitle 18` counter = 0 highlight = `None` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Very long Box title that should wrap 19` subtitle = `This is a long subtitle 19` counter = 0 highlight = `None` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title B 20` subtitle = `Subtitle 20` counter = 1 highlight = `Success` type = `Inactive` unread = abap_false busy = abap_true )
      ( title = `Box title B 21` subtitle = `Subtitle 21` counter = 0 highlight = `None` type = `Navigation` unread = abap_false busy = abap_false )
      ( title = `Box title B 22` subtitle = `Subtitle 22` counter = 5 highlight = `None` type = `Inactive` unread = abap_true busy = abap_false )
      ( title = `Box title B 23` subtitle = `Subtitle 23` counter = 3 highlight = `None` type = `Inactive` unread = abap_true busy = abap_false )
      ( title = `Box title B 24` subtitle = `Subtitle 24` counter = 5 highlight = `Error` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title B 21` subtitle = `Subtitle 21` counter = 0 highlight = `None` type = `Inactive` unread = abap_false busy = abap_false )
      ( title = `Box title B 22` subtitle = `Subtitle 22` counter = 0 highlight = `None` type = `Navigation` unread = abap_true busy = abap_false )
      ( title = `Box title B 23` subtitle = `Subtitle 23` counter = 0 highlight = `None` type = `Navigation` unread = abap_false busy = abap_false )
    ).

  ENDMETHOD.

ENDCLASS.