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MVC中的模型能否回滚到上一个有效状态?

tornadofx kotlin

Leder · 技术社区 · 7 年前

我将从这里开始遵循TornadoFX指南,尝试运行示例向导: Wizard

Cancel 这些值将在上回滚为空值下次开放

2) 当我按下 Finish 下次打开时,这些值仍在向导中

3) 当我现在按下 取消 更改不会回滚到2),而是回滚到 1) ,i。E空旷的田野

我怎样才能与众不同行为:将CustomerModel回滚到上一个有效状态?

这是我的最新资料 CustomerWizard.kt :

package com.example.demo.view

import com.example.demo.app.Customer
import com.example.demo.app.CustomerModel
import tornadofx.*
class CustomerWizard : Wizard("Create customer", "Provide customer information") {
    val customer: CustomerModel by inject()

    override val canGoNext = currentPageComplete
    override val canFinish = allPagesComplete

    override fun onCancel() {
        super.onCancel()
        customer.rollback()

    }

    override fun onSave() {
        super.onSave()
        customer.commit()

        println("customer.name=" + customer.name)
        println("customer.type=" + customer.type)
        println("customer.zip=" + customer.zip)
        println("customer.city=" + customer.city)
    }

    init {
        graphic = resources.imageview("/graphics/customer.png")
        add(BasicData::class)
        add(AddressInput::class)
    }
}

class BasicData : View("Basic Data") {
    val customer: CustomerModel by inject()

    override val complete = customer.valid(customer.name)

    override val root = form {
        fieldset(title) {
            field("Type") {
                combobox(customer.type, Customer.Type.values().toList())
            }
            field("Name") {
                textfield(customer.name).required()
            }
        }
    }
}

class AddressInput : View("Address") {
    val customer: CustomerModel by inject()

    override val complete = customer.valid(customer.zip, customer.city)

    override val root = form {
        fieldset(title) {
            field("Zip/City") {
                textfield(customer.zip) {
                    prefColumnCount = 5
                    required()
                }
                textfield(customer.city).required()
            }
        }
    }
}

CustomerModel.kt :

package com.example.demo.app

import tornadofx.*

class CustomerModel(customer: Customer? = null) : ItemViewModel<Customer>(customer) {
    val name = bind(Customer::nameProperty, autocommit = true)
    val zip  = bind(Customer::zipProperty, autocommit = true)
    val city = bind(Customer::cityProperty, autocommit = true)
    val type = bind(Customer::typeProperty, autocommit = true)
}

MainView.kt :

package com.example.demo.view

import com.example.demo.app.Customer
import com.example.demo.app.CustomerModel
import com.example.demo.app.Styles
import javafx.geometry.Pos
import javafx.scene.layout.Priority
import javafx.scene.paint.Color
import tornadofx.*

class MainView : View("Hello TornadoFX") {

    private val myCustomer: Customer? = Customer("test", 12345, "", Customer.Type.Private)
    override val root = drawer {
            item("Generate & sign", expanded = true) {
                button("Add Customer").action {
                    find<CustomerWizard>(Scope(CustomerModel(myCustomer))).openModal()
                }
            }
            item("Verify") {
                borderpane {
                    top = label("TOP") {
                        useMaxWidth = true
                        alignment = Pos.CENTER
                        style {
                            backgroundColor += Color.RED
                        }
                    }

                    bottom = label("BOTTOM") {
                        useMaxWidth = true
                        alignment = Pos.CENTER
                        style {
                            backgroundColor += Color.BLUE
                        }
                    }

                    left = label("LEFT") {
                        useMaxWidth = true
                        useMaxHeight = true
                        style {
                            backgroundColor += Color.GREEN
                        }
                    }

                    right = label("RIGHT") {
                        useMaxWidth = true
                        useMaxHeight = true
                        style {
                            backgroundColor += Color.PURPLE
                        }
                    }

                    center = label("CENTER") {
                        useMaxWidth = true
                        useMaxHeight = true
                        alignment = Pos.CENTER

                        style {
                            backgroundColor += Color.YELLOW
                        }
                    }
                }
            }
            item("Sign next") {
                borderpane {
                    top = label("TOP") {
                        useMaxWidth = true
                        alignment = Pos.CENTER
                        style {
                            backgroundColor += Color.RED
                        }
                    }

                    bottom = label("BOTTOM") {
                        useMaxWidth = true
                        alignment = Pos.CENTER
                        style {
                            backgroundColor += Color.BLUE
                        }
                    }

                    left = label("LEFT") {
                        useMaxWidth = true
                        useMaxHeight = true
                        style {
                            backgroundColor += Color.GREEN
                        }
                    }

                    right = label("RIGHT") {
                        useMaxWidth = true
                        useMaxHeight = true
                        style {
                            backgroundColor += Color.PURPLE
                        }
                    }

                    center = label("CENTER") {
                        useMaxWidth = true
                        useMaxHeight = true
                        alignment = Pos.CENTER

                        style {
                            backgroundColor += Color.YELLOW
                        }
                    }
                }
            }
        }

        //class Link(val name: String, val uri: String)
        //class Person(val name: String, val nick: String)

        // Sample data variables left out (iPhoneUserAgent, TornadoFXScreencastsURI, people and links)
    }

1 回复 | 直到 7 年前

Edvin Syse 7 年前

当你打电话的时候 rollback() 在 ItemViewModel item ,或如果您从未支持 ItemViewModel 带着一件物品。

Customer 到你的财产 CustomerModel 回滚() 和将从中显示状态

如果在重新打开向导时获得相同的状态,则表示您已重新打开完全相同的向导实例。向导将扩展 View ,这使它成为其范围内的单例,因此如果您只需调用 find() 要定位向导而不指定作用域,第二次尝试将获得与第一次相同的实例。

您没有发布向导初始化代码,但如果要避免此情况,通常应该为向导创建一个新的作用域。如果希望向导编辑特定的客户实例,应执行以下操作:

val model = CustomermerModel()
model.item = myCustomer
find<CustomerWizard>(Scope(model).openModal()

出于这个原因,让视图模型接受构造函数中的实例是正常的,您可以将该实例传递给 ItemViewModel 构造函数,以便自动为您分配项:

class CustomerModel(customer: Customer? = null) : ItemViewModel<Customer>(customer)

并不是说我确保允许CustomerModel使用无参数构造函数,以便在范围中已经没有CustomerModel的情况下支持注入。在这种情况下,将创建一个新的CustomerModel(不支持任何客户项),因此这种情况需要一个无参数构造函数。

find<CustomerWizard>(Scope(CustomerModel(myCustomer)).openModal()

希望这有帮助。