1

我有以下 R3-GUI 脚本：

Rebol [
    file: %context.reb
]

either exists? %r3-gui.r3 [do %r3-gui.r3][load-gui]

view [
    title "First Window"
    hgroup [
        lab: label "fld 1 "
        fld1: field "Field Data 1"
    ]
    button "Display fld 1" on-action [if error? try [probe get-face fld1][alert "Can't read fld1"]]
    button "Display fld 2" on-action [if error? try [probe get-face fld2][alert "Can't read fld2"]]
    button "Open 2nd Window" on-action [
        view [
            title "Second Window"
            hgroup [
                label "fld 2" fld2: field "field 2 data"
            ]
            button "Display fld1" on-action [if error? err: try [probe get-face fld1][probe err alert "Can't read fld1"]]
            button "Display fld2" on-action [if error? err: try [probe get-face fld2][probe err alert "Can't read fld2" ]]
        ]
    ]
]

当我单击第二个窗口中的“显示 fld2”按钮以访问 fld2 的内容时，出现** Script error: fld2 word is not bound to a context错误。这是什么原因？以及如何访问fld2第二个窗口中的单词？

4

2 回答 2

1

因为 fld2 是匿名函数的本地函数，并且未绑定到用户上下文

>> help win-face/facets/tab-face/actors 
WIN-FACE/FACETS/TAB-FACE/ACTORS is a block of value: [on-action make function! [[face arg
        /local fld2 err
    ][
        view layout [
            title "Second Window"
            hgroup [
                label "fld 2" fld2: field "field 2 data"
            ]
            button "Display fld 1" on-action [if error? try [probe get-face fld1] [alert "Can't read fld1"]]
            button "Display fld2" on-action [if error? err: try [probe get-face fld2] [probe err alert "Can't read fld2"]]
        ]
    ]]]
>>

它有效，如果你这样做

 l2: layout [
    title "Second Window"
    hgroup [
       label "fld 2" fld2: field "field 2 data"
    ]
    button "Display fld1" on-action [if error? err: try [probe get-face fld1][probe err alert "Can't read fld1"]]
    button "Display fld2" on-action [if error? err: try [probe get-face fld2][probe err alert "Can't read fld2" ]]
]


view  l1: layout [
   title "First Window"
   hgroup [
       lab: label "fld 1 "
       fld1: field "Field Data 1"
   ]
   button "Display fld 1" on-action [if error? try [probe get-face fld1][alert "Can't read fld1"]]
   button "Display fld 2" on-action [if error? try [probe get-face fld2][alert "Can't read fld2"]]
   button "Open 2nd Window" on-action [
      view l2
   ]
]
于 2014-04-13T14:10:23.240 回答
1

问题的出现是因为该函数创建的匿名函数parse-layout应该是一个闭包，而它不是。请参阅https://gist.github.com/earl/a009454787d9fe4cfaca上的差异解决了该问题。

于 2014-04-14T07:06:54.077 回答