TableView中的JavaFX属性 [英] JavaFX Properties in TableView
问题描述
我正在教自己如何使用TableView中的JavaFX属性,并且遇到了一些属性类型的问题。我有一个对象Person包含两个属性
I am teaching myself how to work with JavaFX properties within the TableView and am having trouble with some property types. I have an object Person that contains two properties
public class Person {
private final StringProperty firstName;
private final IntegerProperty age;
public Person(String firstName, Integer age) {
this.firstName = new SimpleStringProperty(firstName);
this.age = new SimpleIntegerProperty(age);
}
public Integer getAge() {
return age.get();
}
public void setAge(Integer age) {
this.age.set(age);
}
public IntegerProperty ageProperty() {
return age;
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String firstName) {
this.firstName.set(firstName);
}
public StringProperty firstNameProperty() {
return firstName;
}
}
按目标创建后即可使用TableView中的这个对象。我已经像这样创建了两个表格列。
Once created by goal is to use this object in a TableView. I've created the two table columns like this.
TableColumn<Person, String> firstNameColumn = new TableColumn<Person, String>("First Name");
TableColumn<Person, Integer> ageColumn = new TableColumn<Person, Integer>("Age");
然后我想使用Lambda表达式设置单元格值工厂。这就是出现问题的地方。 StringProperty firstName工作得很好。但是,IntegerProperty给出了错误消息类型不匹配:无法从 IntegerProperty
转换为 ObservableValue< Integer>
I then want to set the cell value factory using Lambda expressions. This is where the problem arises. The StringProperty firstName works just fine. However, the IntegerProperty gives me the error message "Type mismatch: cannot convert from IntegerProperty
to ObservableValue<Integer>
"
firstNameColumn.setCellValueFactory(cellData -> cellData.getValue().firstNameProperty());
ageColumn.setCellValueFactory(cellData -> cellData.getValue().ageProperty());
任何人都可以了解ageColumn.setCellValueFactory(...)出了什么问题?任何帮助将不胜感激。
Can anyone shed some light on what is going wrong with the ageColumn.setCellValueFactory(...)? Any help would be greatly appreciated.
谢谢!
推荐答案
一个属性API的一些奇怪的部分是 IntegerProperty
实现 ObservableValue< Number>
,而不是 ObservableValue< ;整数>
。所以,有点违反直觉,你需要
One somewhat strange part of the property API is that IntegerProperty
implements ObservableValue<Number>
, not ObservableValue<Integer>
. So, somewhat counterintuitively, you need
TableColumn<Person, Number> ageColumn = new TableColumn<Person, Number>("Age");
顺便说一句,我不确定这是否会导致问题,但更常见的是使用 int
而不是 Integer
用于get方法的返回类型和模型类中set方法的参数类型。这些匹配 IntegerProperty.get()
和 IntegerProperty.set(...)
的类型,所以它只是避免一些隐式的自动(联合)拳击。
As an aside, and I'm not sure if this causes problems, but it's more usual to use int
instead of Integer
for the return type for the get method and the parameter type for the set method in your model class. These match the types for IntegerProperty.get()
and IntegerProperty.set(...)
, so it just avoids some implicit auto (un)boxing.
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