TornadoFx 将数据从 mysql 传递到表视图

Question

I have a class to pass notes from mysql to tableview in kotlin but i cant seem to make it work Im a little new in kotlin for desktop, only used in android with firebase

This is my class to get the notes

class Notes(id_notes: Int = 0, title: String = "none", description: String = "none"){
private var id_notes: SimpleIntegerProperty = SimpleIntegerProperty(id_notes)
private var title: SimpleStringProperty = SimpleStringProperty(title)
private var description: SimpleStringProperty = SimpleStringProperty(description)

fun getId(): Int {
    return id_notes.get()
}

fun setId(id: Int) {
    id_notes.set(id)
}

fun getTitle(): String {
    return title.get()
}

fun setTitle(Title: String) {
    title.set(Title)
}

fun getDescription(): String {
    return description.get()
}

fun setDescription(Description: String) {
    description.set(Description)
}

then i have the actual code

tableview(data){
                    prefWidth = 400.0
                    column("ID", Notes::getId)
                    column("Title", Notes::getTitle)
                    rowExpander {
                        label {
                            this.text = Notes::getDescription.toString()
                        }
                    }
                }
private fun getNotes(){
    try {

        val notes = Notes()
        val sql = ("SELECT id_notes, title, description, date FROM notes")
        val con: Connection? = Conn.connection()
        stmt = con?.createStatement()
        rs = stmt?.executeQuery(sql)
        while (rs!!.next()) {
            notes.setId(rs!!.getInt("id_notes"))
            notes.setDescription(rs!!.getString("description"))
            notes.setTitle(rs!!.getString("title"))
            data.add(notes.toString())
        }
    } catch (ex: SQLException) {
        alert(Alert.AlertType.ERROR, "Error", "Could not perform this action")
    }
}

Answer 1

At the end I will try to solve your problem, but please, read this part first, because this is far more import for you than the actual answer. I believe your programing skills (for now) are not the required for the kind of things you are trying to accomplish, especially because you are converting your class to string before adding it to your data (which seem to be a collection of string not a collection of Notes), so I don't know how you expect the tableview will get your Id, Title and Description. Also, you have a constructor for Notes, but you are overcomplicating things by not using it and assign values later. In other hand, you getNotes() function is never call in your code, probably is called in some other part you are not showing.

Because of that, I think you should slow down a little bit, try to level up your basic skills (specially working with classes and collections), them read the tornadofx manual, and them try with this kind of stuff.

Now this is my solution. First try this without the database. I did it this way because I don't know if there is any problem with your database. Them change the getNotes() function to the way is in your code, without converting the notes.toString(), just de data.add(notes). Remember to click the button to load the data.

class Prueba: View("MainView") {
    //data should be an FXCollections.observableArrayList<Notes>
    //You didn't show your data variable type, but apparently is some collection of string
    val data = FXCollections.observableArrayList<Notes>()

    override val root = vbox {
        tableview(data){
            prefWidth = 400.0
            column("ID", Notes::getId)
            column("Title", Notes::getTitle)
            rowExpander() {
                label() {
                    //Note the difference here, Notes::getDescription.toString() won't do what you want
                    this.text = it.getDescription()
                }
            }
        }

        //This button is calling the function getNotes(), so data can be loaded
        button("Load Data") {
            action {
                getNotes()
            }
        }
    }

    //Note this function is out side root now
    private fun getNotes() {
        data.clear()
        data.add(Notes(1,"Title 1", "Description 1"))
        data.add(Notes(2,"Title 2", "Description 2"))
        data.add(Notes(3,"Title 3", "Description 3"))
    }
}