69 lines
2.3 KiB
Go
69 lines
2.3 KiB
Go
// This file is part of https://github.com/racingmars/go3270/
|
|
// Copyright 2025 by Matthew R. Wilson, licensed under the MIT license. See
|
|
// LICENSE in the project root for license information.
|
|
|
|
// This example demonstrates using the RunTransactions() approach to
|
|
// structuring a go3270 application.
|
|
|
|
// This file contains the help transaction generator.
|
|
|
|
package main
|
|
|
|
import (
|
|
"net"
|
|
|
|
"github.com/racingmars/go3270"
|
|
)
|
|
|
|
var helpScreen = go3270.Screen{
|
|
{Row: 0, Col: 45, Intense: true, Content: "Online Help"},
|
|
|
|
{Row: 2, Col: 0,
|
|
Content: "This help screen is an example of a transaction that"},
|
|
{Row: 3, Col: 0,
|
|
Content: "can be used as the next transaction from many other transactions"},
|
|
{Row: 4, Col: 0, Content: "and returns to the transaction that called it."},
|
|
|
|
{Row: 6, Col: 0, Content: "Press"},
|
|
{Row: 6, Col: 6, Content: "PF3", Color: go3270.White, Intense: true},
|
|
{Row: 6, Col: 10,
|
|
Content: "to return to the transaction from which you came."},
|
|
|
|
// Error message
|
|
{Row: 21, Col: 0, Name: "errormsg", Color: go3270.Red, Intense: true},
|
|
|
|
// Key legend
|
|
{Row: 23, Col: 1, Content: "F3=Exit"},
|
|
}
|
|
|
|
// The help transaction is an example of returning a closure over a parameter,
|
|
// in this case the desired next transaction. This allows us to use the same
|
|
// transaction from multiple other transactions and return to the requested
|
|
// transaction when the user leaves the help transaction.
|
|
//
|
|
// Any data passed to help will be passed back to the transaction it returns
|
|
// to.
|
|
//
|
|
// The help transaction has no need for any global or session state, so this
|
|
// generator function for it is a stand-alone function and not a method on the
|
|
// session.
|
|
func help(returnTransaction go3270.Tx) go3270.Tx {
|
|
return func(conn net.Conn, data any) (go3270.Tx, any, error) {
|
|
_, err := go3270.HandleScreen(
|
|
helpScreen, // the screen to display
|
|
nil, // (no) rules to enforce
|
|
nil, // pre-populated values in fields
|
|
[]go3270.AID{go3270.AIDPF3}, // keys we accept
|
|
nil,
|
|
"errormsg", // name of field to put error messages in
|
|
23, 79, // cursor coordinates
|
|
conn)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
// Any accepted key returns to the requested returnTransaction
|
|
return returnTransaction, data, nil
|
|
}
|
|
}
|