自动编号表行（javafx）

时间：2013-05-05 13:11:02

标签： javafx tableview tablerow

我的问题是如何在第一列中使用tableRow的索引在JavaFX中创建一个新表。

所以我创建了一个类：NrCellFactory。

public class NrCellFactory<S, String> extends TableCellFactory<S,String> {

private class NrCell<S,String> extends TableCell<S,String>{

    public NrCell(){
        setText(this.getTableRow().getIndex()+"");
    }



}

@Override
protected TableCell<S, String> createTableCell(TableColumn<S, String> column) {
    return new NrCell();
}

}

然后我将我的列设置为应显示数字：

 nrCol.setCellFactory(new NrCellFactory<Person,String>());

当我加载项目时，nrCol没有数据......

任何人都可以解决问题吗？

由于

4 个答案:

答案 0 :(得分：20)

示例解决方案

以下是使用细胞工厂的解决方案：

TableColumn numberCol = new TableColumn("#");
numberCol.setCellValueFactory(new Callback<CellDataFeatures<Person, Person>, ObservableValue<Person>>() {
  @Override public ObservableValue<Person> call(CellDataFeatures<Person, Person> p) {
    return new ReadOnlyObjectWrapper(p.getValue());
  }
});

numberCol.setCellFactory(new Callback<TableColumn<Person, Person>, TableCell<Person, Person>>() {
  @Override public TableCell<Person, Person> call(TableColumn<Person, Person> param) {
    return new TableCell<Person, Person>() {
      @Override protected void updateItem(Person item, boolean empty) {
        super.updateItem(item, empty);

        if (this.getTableRow() != null && item != null) {
          setText(this.getTableRow().getIndex()+"");
        } else {
          setText("");
        }
      }
    };
  }
});
numberCol.setSortable(false);

简单替代解决方案

使用单元格值工厂的简单示例，对于正常情况下没有单元格工厂，表格的后备数据列表中的所有项目都是唯一的，并且可以通过table.getItems().indexOf(p.getValue())查找其索引：< / p> 

TableColumn numberCol = new TableColumn("#");
numberCol.setCellValueFactory(new Callback<CellDataFeatures<Person, String>, ObservableValue<String>>() {
  @Override public ObservableValue<String> call(CellDataFeatures<Person, String> p) {
    return new ReadOnlyObjectWrapper(table.getItems().indexOf(p.getValue()) + "");
  }
});   
numberCol.setSortable(false);

为什么尝试这样做失败

我无法确切地说出为什么尝试这样做会失败，因为我认为您的问题中没有足够的代码来准确诊断故障。我的猜测是你没有为行提供单元格值工厂，也没有在单元格的构造函数中设置文本而不是updateItem调用导致它无法工作。

可执行样本

这是一个可执行的示例：

tableviewnumberedrows 

import javafx.application.Application;
import javafx.beans.property.ReadOnlyObjectWrapper;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Insets;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableColumn.CellDataFeatures;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Callback;

public class NumberedTableViewSample extends Application {

    private TableView<Person> table = new TableView<Person>();
    private final ObservableList<Person> data =
        FXCollections.observableArrayList(
            new Person("Jacob", "Smith", "jacob.smith@example.com"),
            new Person("Isabella", "Johnson", "isabella.johnson@example.com"),
            new Person("Ethan", "Williams", "ethan.williams@example.com"),
            new Person("Emma", "Jones", "emma.jones@example.com"),
            new Person("Michael", "Brown", "michael.brown@example.com")
        );

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        Scene scene = new Scene(new Group());
        stage.setTitle("Table View Sample");
        stage.setWidth(470);
        stage.setHeight(500);

        final Label label = new Label("Address Book");
        label.setFont(new Font("Arial", 20));

        table.setEditable(true);

        TableColumn numberCol = new TableColumn("#");
        numberCol.setMinWidth(20);
        numberCol.setCellValueFactory(new Callback<CellDataFeatures<Person, Person>, ObservableValue<Person>>() {
            @Override public ObservableValue<Person> call(CellDataFeatures<Person, Person> p) {
                return new ReadOnlyObjectWrapper(p.getValue());
            }
        });

        numberCol.setCellFactory(new Callback<TableColumn<Person, Person>, TableCell<Person, Person>>() {
            @Override public TableCell<Person, Person> call(TableColumn<Person, Person> param) {
                return new TableCell<Person, Person>() {
                    @Override protected void updateItem(Person item, boolean empty) {
                        super.updateItem(item, empty);

                        if (this.getTableRow() != null && item != null) {
                            setText(this.getTableRow().getIndex()+"");
                        } else {
                            setText("");
                        }
                    }
                };
            }
        });
        numberCol.setSortable(false);

        TableColumn firstNameCol = new TableColumn("First Name");
        firstNameCol.setMinWidth(100);
        firstNameCol.setCellValueFactory(
                new PropertyValueFactory<Person, String>("firstName"));

        TableColumn lastNameCol = new TableColumn("Last Name");
        lastNameCol.setMinWidth(100);
        lastNameCol.setCellValueFactory(
                new PropertyValueFactory<Person, String>("lastName"));

        TableColumn emailCol = new TableColumn("Email");
        emailCol.setMinWidth(200);
        emailCol.setCellValueFactory(
                new PropertyValueFactory<Person, String>("email"));

        table.setItems(data);
        table.getColumns().addAll(numberCol, firstNameCol, lastNameCol, emailCol);

        final VBox vbox = new VBox();
        vbox.setSpacing(5);
        vbox.setPadding(new Insets(10, 0, 0, 10));
        vbox.getChildren().addAll(label, table);

        ((Group) scene.getRoot()).getChildren().addAll(vbox);
        stage.setScene(scene);
        stage.show();
    }

    public static class Person {

        private final SimpleStringProperty firstName;
        private final SimpleStringProperty lastName;
        private final SimpleStringProperty email;

        private Person(String fName, String lName, String email) {
            this.firstName = new SimpleStringProperty(fName);
            this.lastName = new SimpleStringProperty(lName);
            this.email = new SimpleStringProperty(email);
        }

        public String getFirstName() {
            return firstName.get();
        }

        public void setFirstName(String fName) {
            firstName.set(fName);
        }

        public String getLastName() {
            return lastName.get();
        }

        public void setLastName(String fName) {
            lastName.set(fName);
        }

        public String getEmail() {
            return email.get();
        }

        public void setEmail(String fName) {
            email.set(fName);
        }
    }
}

答案 1 :(得分：16)

在java 8中，使用lambda表达式可以更轻松地完成：

TableColumn<Person, Number> indexColumn = new TableColumn<Person, Number>("#");
indexColumn.setSortable(false);
indexColumn.setCellValueFactory(column-> new ReadOnlyObjectWrapper<Number>(YourTable.getItems().indexOf(column.getValue())));

答案 2 :(得分：3)

这是一个可以在任何地方使用的通用（通用）单元工厂：

org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project com.aepona.monetization.core: Compilation failure
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.apache.maven.plugin.compiler.CompilationFailureException: Compilation failure
    at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:858)
    at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:129)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
    ... 20 more

用法：public class LineNumbersCellFactory<T, E> implements Callback<TableColumn<T, E>, TableCell<T, E>> { public LineNumbersCellFactory() { } @Override public TableCell<T, E> call(TableColumn<T, E> param) { return new TableCell<T, E>() { @Override protected void updateItem(E item, boolean empty) { super.updateItem(item, empty); if (!empty) { setText(this.getTableRow().getIndex() + 1 + ""); } else { setText(""); } } }; } }

如果您需要0索引行，请删除+1。

编辑：删除项目时添加了colRowNum.setCellFactory(new LineNumbersCellFactory());阻止

答案 3 :(得分：0)

一种不依赖于indexOf(item)或updateItem()的简单方法（可能是或者可能不是您需要监听的唯一事件）是绑定文本属性TableCell到其行索引：

TableColumn<S, Integer> indexColumn = new TableColumn<>();
indexColumn.setCellFactory(col -> {
  TableCell<S, Integer> indexCell = new TableCell<>();
  ReadOnlyObjectProperty<TableRow<S>> rowProperty = indexCell.tableRowProperty();
  ObjectBinding<String> rowBinding = Bindings.createObjectBinding(() -> {
    TableRow<S> row = rowProperty.get();
    if (row != null) { // can be null during CSS processing
      int rowIndex = row.getIndex();
      if (rowIndex < row.getTableView().getItems().size()) {
        return Integer.toString(rowIndex);
      }
    }
    return null;
  }, rowProperty);
  indexCell.textProperty().bind(rowBinding);
  return indexCell;
});

indexing only rows with data

如果您不关心行是否包含数据，则可以删除rowIndex < ...size()支票：

TableRow<S> row = rowProperty.get();
return row == null ? null : Integer.toString(row.getIndex());

indexing all rows

相关问题
最新问题