Java/Vaadin -FormLayout 自定义隐藏组件实现

Question

我正在使用 vaadin 开发 Web 应用程序，目前正在尝试实现地址簿。我查看了 github 上的官方实现并尝试构建它。

我遇到的问题与联系表有关。我希望能够单击网格中的一行并打开包含信息的表单。 (类似于他们的例子是如何完成的)

然而，该组件没有按预期使用react。如果我将组件直接添加到主布局并尝试切换可见性，它会弄乱 View 。我让它工作的唯一方法是根据需要添加和删除组件，尽管我不喜欢这个解决方案，也不优雅。

这是当前的实现

package com.example.ecenter.view;

import com.vaadin.data.Binder;
import com.vaadin.navigator.View;
import com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;
import com.vaadin.spring.annotation.SpringComponent;
import com.vaadin.spring.annotation.SpringView;
import com.vaadin.ui.Button;
import com.vaadin.ui.FormLayout;
import com.vaadin.ui.Grid;
import com.vaadin.ui.HorizontalLayout;
import com.vaadin.ui.TextField;
import com.vaadin.ui.VerticalLayout;
import com.vaadin.ui.themes.ValoTheme;

import io.valhala.ecenter.temp.Client;

import java.util.Arrays;
import java.util.List;

@SpringView(name = AddressBookView.VIEW_NAME)
@SpringComponent
public class AddressBookView extends HorizontalLayout implements View
{
    public static final String VIEW_NAME = "Address Book";
    Grid<Client> contactList = new Grid<>(Client.class);
    private List<Client> clients = Arrays.asList(
        new Client("Sernie", "A", "123 Test St.", "test@gmail.gov", "555-555-5554"),
        new Client("Ernie", "B", "123 Test St.", "test@gmail.com", "555-555-5555"),
        new Client("Bernie", "C", "123 Test St.", "test@gmail.net", "555-555-5556"),
        new Client("Ayy", "Lmao", "123 Test St.", "test@gmail.org", "555-555-5557"),
        new Client("Dax", "E", "123 Test St.", "test@gmail.net", "555-555-5558"),
        new Client("Avorion", "F", "123 Test St.", "test@gmail.net", "555-555-5559"),
        new Client("Xanion", "G", "123 Test St.", "test@gmail.net", "555-555-5560"),
        new Client("Trinium", "H", "123 Test St.", "test@gmail.net", "555-555-5561"),
        new Client("Naonite", "I", "123 Test St.", "test@gmail.net", "555-555-5562"),
        new Client("Squillium", "J", "123 Test St.", "test@gmail.net", "555-555-5563"),
        new Client("Picard", "K", "123 Test St.", "test@gmail.net", "555-555-5564"),
        new Client("Richard", "L", "123 Test St.", "test@gmail.net", "555-555-5565"),
        new Client("Rickard", "M", "123 Test St.", "test@gmail.net", "555-555-5566"),
        new Client("Bobby", "N", "123 Test St.", "test@gmail.net", "555-555-5567"),
        new Client("Bob", "O", "123 Test St.", "test@gmail.net", "555-555-5568"),
        new Client("Ron", "P", "123 Test St.", "test@gmail.net", "555-555-5569"),
        new Client("Bill", "Q", "123 Test St.", "test@gmail.net", "555-555-5570"),
        new Client("Greg", "R", "123 Test St.", "test@gmail.net", "555-555-5571"),
        new Client("Juan", "S", "123 Test St.", "test@gmail.net", "555-555-5572"),
        new Client("Squidward", "T", "123 Test St.", "test@gmail.net", "555-555-5573"));

private ContactForm contactForm = new ContactForm();
private TextField filter = new TextField();
private Button addContact = new Button("New Client");

public AddressBookView()
{
    initConfig();
    buildLayout();
}

private void buildLayout() 
{
    HorizontalLayout actionBar = new HorizontalLayout(filter, addContact);
    actionBar.setWidth("100%");
    filter.setWidth("100%");
    actionBar.setExpandRatio(filter, 1);

    VerticalLayout left = new VerticalLayout(actionBar, contactList);
    left.setSizeFull();
    contactList.setSizeFull();
    left.setExpandRatio(contactList, 1);

    HorizontalLayout mainLayout = new HorizontalLayout(left);
    mainLayout.setSizeFull();
    mainLayout.setExpandRatio(left, 1);

    //HorizontalLayout test = new HorizontalLayout(contactForm);
    addComponent(mainLayout);

    //addComponent(test);
    /*
     * even using a different layout still messes it up
     */

    //contactForm.setVisible(false);
}

private void initConfig() 
{
    addContact.addClickListener(event -> 
    {
        addComponent(contactForm);
        contactForm.setClient(new Client());
    });

    filter.setPlaceholder("Search clients...");
    addContact.addStyleName(ValoTheme.BUTTON_PRIMARY);
    //filter.addValueChangeListener(e -> refreshContacts(e.getText()));

    contactList.setSelectionMode(Grid.SelectionMode.SINGLE);
    contactList.setColumns("firstName", "lastName");
    contactList.setItems(clients);

    contactList.asSingleSelect().addValueChangeListener(event -> 
    {
        if(event.getValue() == null)
        {
            removeComponent(contactForm); //quick and dirty workaround
        }
        else
        {
            addComponent(contactForm); //quick and dirty workaround
            /* contactForm.setVisible(true); messes up the entire view */
            contactForm.setClient(event.getValue());
        }
    });
}

@Override
public void enter(ViewChangeEvent event) {
}

private class ContactForm extends FormLayout
{
    private Client client;
    private Button save, delete, cancel;
    private TextField firstName, lastName, email, address, phoneNumber;
    private Binder<Client> binder = new Binder<>(Client.class);
    public ContactForm()
    {
        initConf();
        initLayout();
        setSizeUndefined();
        binder.bindInstanceFields(this);
    }

    public void initConf() 
    {
        save = new Button("Save");
        cancel = new Button("Cancel");

        firstName = new TextField();
        firstName.setPlaceholder("First Name");

        lastName = new TextField();
        lastName.setPlaceholder("Last Name");

        email = new TextField();
        email.setPlaceholder("Email Address");

        address = new TextField();
        address.setPlaceholder("Address");

        phoneNumber = new TextField();
        phoneNumber.setPlaceholder("Phone Number");

    }
    public void initLayout() 
    {
        HorizontalLayout actions = new HorizontalLayout(save, cancel);
        actions.setSpacing(true);

        addComponents(actions, firstName, lastName, email, address, phoneNumber);
    }

    public void setClient(Client client)
    {
        //setVisible(true);
        this.client = client;
        binder.setBean(client);
    }
  }
}

第一张图片显示了将表单添加到布局并将其设置为隐藏时 View 的 react 。

第二张和第三张图片显示了 View 应该如何 react 。虽然为了达到预期的结果，我不得不马虎地编码。

最后是问题:

我该如何解决这个问题？我试过为表单使用内部类并将其创建为自己的类。我唯一的猜测是，在 github 实现中，他们将 UI 传递给这种形式，其中地址簿扩展了 UI 而不是组件。

Answer 1

发生的情况是，您离开 View (水平布局)时未定义大小并将大小设置为完整加上隐藏表单的组合会产生奇怪的结果。因此，如果您使用一些开发人员工具检查生成的元素，您会看到您的 View (水平布局)的高度为 147 像素，而网格表包装器的高度为 24 像素:

如果您将 View 高度设置为 100%，那么它会扩展以占据所有可用空间，这可能不是您想要的:

因此，只需保留 left 大小未定义，并丢失 mainLayout(您的 View 已经扩展了 Horizo​​ntalLayout，所以只需使用它)然后继续回到使用 contactForm.setVisible(true/false)。这样 left 布局将扩展以适应为操作栏 + 网格计算的任何大小:

private void buildLayout() {
    HorizontalLayout actionBar = new HorizontalLayout(filter, addContact);
    actionBar.setWidth("100%");
    filter.setWidth("100%");
    actionBar.setExpandRatio(filter, 1);

    VerticalLayout left = new VerticalLayout(actionBar, contactList);
    left.setSizeFull();
    left.setExpandRatio(contactList, 1);

    addComponents(left, contactForm);
    contactForm.setVisible(false);
}

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P.S. 如果有人可以通过提供有关在这种情况下如何计算尺寸的更多见解来改进此答案，请编辑此答案!