其他监视属性的绑定判断

• 另一个构造器SimpleIntegerProperty y = new SimpleIntegerProperty(student, "stu", 10);

• 以下方法创建不能修改的监视属性IntegerExpression n = SimpleIntegerProperty.integerExpression(y);

• 强制类型转换SimpleIntegerProperty sip = (SimpleIntegerProperty) n;

  x.set(90);
  System.out.println("n.get() = " + n.get());  
  System.out.println("((SimpleIntegerProperty) n).getBean() = " + ((SimpleIntegerProperty) n).getBean());  
  System.out.println("sip.getName().equals(y.getName()) = " + sip.getName().equals(y.getName()));
  

  n.get() = 10 ((SimpleIntegerProperty) n).getBean() = Student{name='reine', age=18} sip.getName().equals(y.getName()) = true

• 类型转换

  ObjectProperty<Integer> objectProperty = new SimpleObjectProperty<>(2);  
  System.out.println(IntegerExpression.integerExpression(objectProperty).get());
  

  2

• 获取只读属性SimpleIntegerProperty.readOnlyIntegerProperty(y);

布尔类型的监视属性

SimpleBooleanProperty b1 = new SimpleBooleanProperty(true);  
SimpleBooleanProperty b2 = new SimpleBooleanProperty(false);  
// 与或非  
b1.and(b2);  
b1.or(b2);  
b1.not();  
b1.isEqualTo(b2);  
b1.isNotEqualTo(b2);

字符串类型的监视属性

• 创建两个变量

  SimpleStringProperty up = new SimpleStringProperty("ABC");  
  SimpleStringProperty low = new SimpleStringProperty("abc");
  

• 操作

  System.out.println("up.lessThan(low).get() = " + up.lessThan(low).get());  
  System.out.println("up.concat(low).get() = " + up.concat(low).get());  
  System.out.println("up.isEqualTo(low).get() = " + up.isEqualTo(low).get());  
  System.out.println("up.isEqualToIgnoreCase(low).get() = " + up.isEqualToIgnoreCase(low).get());  
  up.set("");  
  System.out.println("up.isEmpty().get() = " + up.isEmpty().get()); // true  
  System.out.println("up.isNull().get() = " + up.isNull().get()); // false
  

  up.lessThan(low).get() = true up.concat(low).get() = ABCabc up.isEqualTo(low).get() = false up.isEqualToIgnoreCase(low).get() = true up.isEmpty().get() = true up.isNull().get() = false

对象类型的监视属性

• 创建属性SimpleObjectProperty<Student> studentSimpleObjectProperty = new SimpleObjectProperty<>(student);

• 添加属性监听器

  studentSimpleObjectProperty.addListener(((observable, oldValue, newValue) -> {  
      System.out.println("oldValue = " + oldValue);  
      System.out.println("newValue = " + newValue);  
  }));
  

• 测试

  // 触发监听器 
  studentSimpleObjectProperty.set(new Student("Jack",82));  
  // 不触发监听器 
  student.setName("Tom");  
  // 不触发监听器  
  studentSimpleObjectProperty.get().setAge(19);
  System.out.println("studentSimpleObjectProperty.isNull().get() = " + studentSimpleObjectProperty.isNull().get());
  

  oldValue = Student{name='reine', age=18} newValue = Student{name='Jack', age=82} studentSimpleObjectProperty.isNull().get() = false