I am trying to display a list of users on a table. I write the following code in order to complete the table, however the Boolean values are not displayed on checkboxes (they are always populated as empty / false when there are actually several that are true). As a test I an just adding a single object that I am creating "manually"
Below is the code:
TableView<User> objTable = new TableView<User>();
objTable.setEditable(true);
ObservableList<User> objList = FXCollections.observableArrayList(new User("User 1", true);
TableColumn objColumnName = new TableColumn<User, String>("Column Name");
TableColumn objColumnActive = new TableColumn<User, Boolean>("Active");
objColumnName.setCellValueFactory(new PropertyValueFactory<User, String>("DisplayName"));
objColumnActive.setCellValueFactory(new PropertyValueFactory<UserRequestVO, Boolean>("Active"));
objTable.getColumns().addAll(objColumn);
objTable.setItems(objList);
User Class
public class user
{
private String strFirstName;
private Boolean bolActive;
public Boolean getActive()
{
return this.bolActive
}
}
I also try renaming getActive function as isActive, but there were no changes
You should use properties,
In your user class, you would store your boolean as a SimpleBooleanProperty :
private SimpleBooleanProperty bolActive;
Instantiated like so : this.bolActive = new SimpleBooleanProperty(false); //Or true instead of false
Now create a getter for the property, the property value, and a setter for the property value :
public BooleanProperty bolActiveProperty(){
return bolActive;
}
public final Boolean getBolActive() {
return bolActive.get();
}
public final void setBolActive(Boolean bolActive) {
this.bolActive.set(bolActive);
}
Now when you create your table columns, you do this :
objColumnActive.setCellValueFactory(cellData -> cellData.getValue().bolActiveProperty());
Or if you prefer old school java :
objColumnActive.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<User,Boolean>, ObservableValue<Boolean>>() {
#Override
public ObservableValue<Boolean> call(CellDataFeatures<User, Boolean> cellData) {
return cellData.getValue().bolActiveProperty();
}
});
This also work I think, might be wrong though :
objColumnActive.setCellValueFactory(new PropertyValueFactory<User, Boolean>("bolActive"));
This will allow you to bind the User property to the column, so that any modification of the column will affect the value in the user.
Nice thing is you can listen to the value modification using myProperty.addListener((obs, oldV, newV) -> { /* Your code */ });
Where obs is the value observed, oldV the old value, and newV the new value (obviously)
Does that help/work for you?
Related
In app I'm bulding I used data model presented by James_D here:
Applying MVC With JavaFx
I just can find a way to bind labels text to property of object held in DataModel
Data is structured like this:
model class Student
//partial class
public class Student {
private final StringProperty displayName = new SimpleStringProperty();
public final StringProperty displayNameProperty(){
return this.displayName;
}
public Student(){
}
public final String getDisplayName() {
return this.displayNameProperty().get();
}
public final void setDisplayName(String displayName) {
this.displayNameProperty().set(displayName);
}
}
Student instaces are held by StudentDataModel class
public class StudentDataModel {
// complete student list
private final ObservableList<Student> studentList = FXCollections.observableArrayList();
private final ObjectProperty<Student> selectedStudent = new SimpleObjectProperty<>(new Student());
public final Student getSelectedStudent() {
return selectedStudent.get();
}
public final ObjectProperty<Student> selectedStudentProperty() {
return selectedStudent;
}
public final void setSelectedStudent(Student student) {
selectedStudent.set(student);
}
}
StudentList is displayed by Table View, there is change listener that sets selectedStudent like this:
public class TableViewController {
public void initModel(StudentDataModel studentDM) {
// ensure model is set once
if (this.studentDM != null) {
throw new IllegalStateException("StudentDataModel can only be initialized once");
}
this.studentDM = studentDM;
tableView.getSelectionModel().selectedItemProperty().addListener((obs, oldSelection, newSelection) -> {
if (newSelection != null) {
studentDM.setSelectedStudent(newSelection);
}
});
}}
There is another controller ActionsBarController that has label to display selected student (this seems redundant, but there is option for selecting multiple objects to perform bulk operations).
StudentDataModel is initialized properly (I can see it in debuger) but below doesn't do anything:
chosenStudentLabel.textProperty().bind(studentDM.getSelectedStudent().displayNameProperty());
//this shows class name with instance number changing correctly
chosenStudentLabel.textProperty().bind(studentDM.selectedStudentProperty().asString());
I could inject ActionsBarController to TableViewController and change label text from change Listener there, but this seems counter productive with data model.
What am I doing wrong?
Your code doesn't work, because you call (and evaluate) getSelectedStudent() at the time the binding is created (i.e. when you initialize the model). As a consequence, you only bind to the displayName property of the student that is selected at that time. (If nothing is selected, you'll get a NullPointerException.) The binding will only change if that initially-selected student's display name changes; it won't change if the selection changes.
You need a binding that unbinds from the old selected student's display name, and binds to the new selected student's display name, when the selected student changes. One way to do this is:
chosenStudentLabel.textProperty().bind(new StringBinding() {
{
studentDM.selectedStudentProperty().addListener((obs, oldStudent, newStudent) -> {
if (oldStudent != null) {
unbind(oldStudent.displayNameProperty());
}
if (newStudent != null) {
bind(newStudent.displayNameProperty());
}
invalidate();
});
}
#Override
protected String computeValue() {
if (studentDM.getSelectedStudent() == null) {
return "" ;
}
return studentDM.getSelectedStudent().getDisplayName();
}
});
Note that there is also a "built-in" way to do this, but it's a bit unsatisfactory (in my opinion) for a couple of reasons. Firstly, it relies on specifying the name of the "nested property" as a String, using reflection to access it. This is undesirable because it has no way to check the property exists at compile time, it requires opening the module for access, and it is less good performance-wise. Secondly, it gives spurious warnings if one of the properties in the "chain" is null (e.g. in this case if the selected student is null, which is will be initially), even though this is a supported case according to the documentation. However, it is significantly less code:
chosenStudentLabel.textProperty().bind(
Bindings.selectString(studentDM.selectedStudentProperty(), "displayName")
);
This has baffled me for a while now and I cannot seem to get the grasp of it. I'm using Cell Value Factory to populate a simple one column table and it does not populate in the table.
It does and I click the rows that are populated but I do not see any values in them- in this case String values. [I just edited this to make it clearer]
I have a different project under which it works under the same kind of data model. What am I doing wrong?
Here's the code. The commented code at the end seems to work though. I've checked to see if the usual mistakes- creating a new column instance or a new tableview instance, are there. Nothing. Please help!
//Simple Data Model
Stock.java
public class Stock {
private SimpleStringProperty stockTicker;
public Stock(String stockTicker) {
this.stockTicker = new SimpleStringProperty(stockTicker);
}
public String getstockTicker() {
return stockTicker.get();
}
public void setstockTicker(String stockticker) {
stockTicker.set(stockticker);
}
}
//Controller class
MainGuiController.java
private ObservableList<Stock> data;
#FXML
private TableView<Stock> stockTableView;// = new TableView<>(data);
#FXML
private TableColumn<Stock, String> tickerCol;
private void setTickersToCol() {
try {
Statement stmt = conn.createStatement();//conn is defined and works
ResultSet rsltset = stmt.executeQuery("SELECT ticker FROM tickerlist order by ticker");
data = FXCollections.observableArrayList();
Stock stockInstance;
while (rsltset.next()) {
stockInstance = new Stock(rsltset.getString(1).toUpperCase());
data.add(stockInstance);
}
} catch (SQLException ex) {
Logger.getLogger(WriteToFile.class.getName()).log(Level.SEVERE, null, ex);
System.out.println("Connection Failed! Check output console");
}
tickerCol.setCellValueFactory(new PropertyValueFactory<Stock,String>("stockTicker"));
stockTableView.setItems(data);
}
/*THIS, ON THE OTHER HAND, WORKS*/
/*Callback<CellDataFeatures<Stock, String>, ObservableValue<String>> cellDataFeat =
new Callback<CellDataFeatures<Stock, String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(CellDataFeatures<Stock, String> p) {
return new SimpleStringProperty(p.getValue().getstockTicker());
}
};*/
Suggested solution (use a Lambda, not a PropertyValueFactory)
Instead of:
aColumn.setCellValueFactory(new PropertyValueFactory<Appointment,LocalDate>("date"));
Write:
aColumn.setCellValueFactory(cellData -> cellData.getValue().dateProperty());
For more information, see this answer:
Java: setCellValuefactory; Lambda vs. PropertyValueFactory; advantages/disadvantages
Solution using PropertyValueFactory
The lambda solution outlined above is preferred, but if you wish to use PropertyValueFactory, this alternate solution provides information on that.
How to Fix It
The case of your getter and setter methods are wrong.
getstockTicker should be getStockTicker
setstockTicker should be setStockTicker
Some Background Information
Your PropertyValueFactory remains the same with:
new PropertyValueFactory<Stock,String>("stockTicker")
The naming convention will seem more obvious when you also add a property accessor to your Stock class:
public class Stock {
private SimpleStringProperty stockTicker;
public Stock(String stockTicker) {
this.stockTicker = new SimpleStringProperty(stockTicker);
}
public String getStockTicker() {
return stockTicker.get();
}
public void setStockTicker(String stockticker) {
stockTicker.set(stockticker);
}
public StringProperty stockTickerProperty() {
return stockTicker;
}
}
The PropertyValueFactory uses reflection to find the relevant accessors (these should be public). First, it will try to use the stockTickerProperty accessor and, if that is not present fall back to getters and setters. Providing a property accessor is recommended as then you will automatically enable your table to observe the property in the underlying model, dynamically updating its data as the underlying model changes.
put the Getter and Setter method in you data class for all the elements.
I wanted to program a TableBrowser for a MYSQl Database in JavaFX.
My first problem is: i dont know which types i get back from the Database.
So i decided to wrap those types with a Wrapper-class.
To show these values on the GUI, i used the TableColumns setCellValueFactory-method, which
needs a value, that implements ObservableValue.
So i tried to implement the ObservableValue-interface.
But when i run the program it doesnt show the right Values.
TableBrowser after connecting to the Database
Has anyone an idea where i did wrong or knows a more recommended way to implement it ?
Here is the Part of the Code from the TableBrowser
/*
* this variable is used to iterate over the tableview's columns.
* It is a class variable, because it is not possible (for some reasons)
* to use a local variable while working with it in the context of Lambda-expressions
*/
int t = 0;
// those two variables are defined in the class Body
private final TableView<Entry> tableview = new TableView<>();
private final ObservableList<Entry> columndata = FXCollections.observableArrayList();
// the following Code is inside the Button's Actionlistener
for(int i = 1; i <= maxcol; i++) // adds a new TableColum for every colum in the DB
{
tableview.getColumns().add(new TableColumn<Entry, String>rsmd.getColumnName(i)));
}
// iterates over the ResultSet
while(rs.next())
{
// this is the dataset i put in my TableView
Entry row = new Entry(maxcol);
// for each Column i add the columnvalue to the current dataset
for(int i = 1; i <= maxcol; i++)
{
int type = rsmd.getColumnType(i);
Object value = rs.getObject(i);
row.setCellValue(i-1, type, value);
}
// adds a new dataset to the ObservableList<Entry>
columndata.add(row);
}
// puts all datasets in the TableView
tableview.setItems(columndata);
// iterates over all Columns
for(t = 0; t < tableview.getColumns().size(); t++)
{
// should set the CellValueFactory for each Column so it shows the data
/*
* I apologise if there a horrible mistake.
* I never worked with Lamda before and just copied it form an example page :)
*/
tableview.getColumns().get(t).setCellValueFactory(celldata -> celldata.getValue().getCellValue(t-1));
}
This is my Entry class, which is an inner Class in TableBrowserclass
/*
* should represent a Dataset.
* Has an array, which holdes every columnvalue as a WrapperType
*/
private class Entry
{
WrapperType<?>[] columns;
private Entry(int columncount)
{
columns = new WrapperType[columncount];
}
private WrapperType<?> getCellValue(int col)
{
return columns[col];
}
private void setCellValue(int col, int type, Object value)
{
columns[col] = MySQLTypeWrapper.getInstance().wrapType(type, value);
}
}
Here is the MySQLTypeWrapper class, which holds the WrapperType as an inner class
public class MySQLTypeWrapper
{
public WrapperType<?> wrapType(int type, Object Value)
{
Class<?> typeclass = toClass(type);
return new WrapperType<>(typeclass.cast(Value));
}
/*
* returns the appropriate class def for every database type
* Expl: VARCHAR returns String.class
*/
private static Class<?> toClass(int type) {...}
/*
* I copied the content of the of the overridden Methods from StringPropertyBase
* as i have clue how to implement ObservableValue
*/
class WrapperType<T> implements ObservableValue<WrapperType<T>>
{
private T value;
private ExpressionHelper<WrapperType<T>> helper = null;
private WrapperType(T value)
{
this.value = value;
}
#Override
public void addListener(InvalidationListener listener)
{
helper = ExpressionHelper.addListener(helper, this, listener);
}
#Override
public void removeListener(InvalidationListener listener)
{
helper = ExpressionHelper.removeListener(helper, listener);
}
#Override
public void addListener(ChangeListener<? super WrapperType<T>> listener)
{
helper = ExpressionHelper.addListener(helper, this, listener);
}
#Override
public void removeListener(ChangeListener<? super WrapperType<T>> listener)
{
helper = ExpressionHelper.removeListener(helper, listener);
}
#Override
public WrapperType<T> getValue()
{
return this;
}
public String toString()
{
return value.toString();
}
}
}
Thanks for your help in advance :)
As mentioned in the comments, your first problem was not using the TableView's Items property.
For the second part - one solution would be to create a helper method along the lines of
private <T> Callback<TableColumn.CellDataFeatures<Entry,T>,ObservableValue<T>> createCellFactory(int columnIndex) {
return celldata -> celldata.getValue().getCellValue(columnIndex);
}
and then change the loop to
// Now t can be a local variable, as it is not directly passed to the lambda.
for(int t = 0; t < tableview.getColumns().size(); t++)
{
// should set the CellValueFactory for each Column so it shows the data
tableview.getColumns().get(t).setCellValueFactory(createCellFactory(t));
}
Note that this time the variable passed to the lambda is a local effectively-final variable and not an instance variable, so the lambda is created with the correct value every time.
One last word of advice - are you sure you need this amount of generality? What I mean is - it is usually better to create a class to directly represent your DB structure with proper getters and setters, then you can use PropertyValueFactory.
Good day,
I have a fixed number of columns in TableView, however I need to populate column by column, not row by row, as one column data depends on the previous one. Is there an example of such thing? I have searched for such way, but unfortunately. Hope I made it understandable.
Since nobody provided me an example, and the comment was not very helpful I manage to solve my problem in the following way (in my case one column result depends on the previous one and the number of elements can be different as well as the number of columns are predefined)
Simple example:
We have an object:
public class Cars{
private String name;
private String company;
private String year;
public Cars(String name,String company,String year){
this.name=name;
this.company=company;
this.year=year;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name= name;
}
public String getCompany() {
return company;
}
public void setCompany(String company) {
this.company= company;
}
public String getYear() {
return year;
}
public void setYear(String year) {
this.year= year;
}
}
Then we have our table:
public TableView createTable() {
TableView<Cars> table = new TableView<>();
TableColumn<Cars, String> nameyColumn = new TableColumn("Name");
nameColumn.setCellValueFactory(new PropertyValueFactory<>("name"));
TableColumn<Cars, String> companyColumn = new TableColumn<>("Company");
companyColumn.setCellValueFactory(new PropertyValueFactory<>("company"));
TableColumn<Cars, String> yearColumn = new TableColumn<>("Year");
yearColumn.setCellValueFactory(new PropertyValueFactory<>("year"));
table.setItems(makeCars());
table.getColumns().addAll(nameColumn, companyColumn, yearColumn);
return table;
}
Afterwards we generate the information that we want to put into the table and put all the information into, in this case a String Array. So if we have 3 String arrays we can make an ArrayListlist of arrays and populate it with information.
However, the sizes of the String arrays inside the ArrayList have to be predefined, so that you would not get a NullPointException where the at one point you have a car's name and you dont have a year it will be set to an empty automatically, as an empty predefined String array contains null as elements automatically. So in my case I know the max size that one array can be and set all of them to the same size.
And afterwards I just loop through the ArrayList of String Arrays and create objects which I add to the ObservableList ( might be a better way of doing it but I did it this way):
private ObservableList<Cars> makeCars() {
ObservableList<Cars> madeList = FXCollections.observableArrayList();
ArrayList<String[]>arrayOfArrays=new ArrayList<>();
for(int i=0;i<maxRow;i++){
madeList.add(new Cars(arrayOfArrays.get(0)[i],arrayOfArrays.get(1)[i],
arrayOfArrays.get(2)[i]));
}
return madeList;
}
Hope this will helpful to somebody, if there is a better way and I am overdoing it please share.
I'm struggling to create a dynamic view generation utility for javafx. I've a handful of Classes that have ObjectProperty's or StringProperty's I'd like to create a ComboBox for each property and bind directly the combo selected value to the Class property by name if possible. Is there some helper or method in any of the javafx.beans.binding that would allow me to specify an Object and a String name and retrieve the property. Or to just retrieve a list of properties. I have a method now that takes the string and matches it to the property by name but it requires I have a case for each property on the object, which on an object with 20+ properties is a lot of duplicate code.
I guess to specify I'm looking for javafx.bean.property as a return type.
You can always use Java Reflection.
Getting a list of properties
for (Method method : Node.class.getMethods()) {
String name = method.getName();
if (name.endsWith("Property")) {
Type returnType = method.getReturnType();
String propName = name.replace("Property", "");
System.out.println(propName + " : " + returnType);
}
}
Here is reflective method for binding and example:
public class ReflectiveBind extends Application {
/**
* Reflection call for code like
* slider1.valueProperty().bindBidirectional(slider2.valueProperty());
*
* #param bindee Node which you want to be changed by binding
* #param propertyName name of the property, e.g. width
* #param bindTarget Node which you want to be updated by binding
*/
private static void bind(Object bindee, String propertyName, Object bindTarget) throws Exception {
// here we get slider1.valueProperty()
Method methodForBindee = bindee.getClass().getMethod(propertyName + "Property", (Class[]) null);
Object bindableObj = methodForBindee.invoke(bindee);
// here we get slider2.valueProperty()
Method methodForBindTarget = bindTarget.getClass().getMethod(propertyName + "Property", (Class[]) null);
Object bindTargetObj = methodForBindTarget.invoke(bindTarget);
// here we call bindBidirectional: slider1.valueProperty().bindBidirectional(slider2.valueProperty())
Method bindMethod = bindableObj.getClass().getMethod("bindBidirectional", Property.class);
bindMethod.invoke(bindableObj, bindTargetObj);
}
#Override
public void start(Stage stage) {
Slider slider1 = new Slider();
Slider slider2 = new Slider();
VBox root = new VBox(20);
root.getChildren().addAll(slider1, slider2);
stage.setScene(new Scene(root, 200, 100));
stage.show();
try {
//same call as slider1.valueProperty().bindBidirectional(slider2.valueProperty());
bind(slider1, "value", slider2);
} catch (Exception ex) {
ex.printStackTrace();
}
}
public static void main(String[] args) { launch(); }
}
Check out apache commons bean utils
http://commons.apache.org/beanutils/
You say you want to...
Get the value of the property:
http://commons.apache.org/beanutils/api/org/apache/commons/beanutils/BeanUtils.html#getProperty%28java.lang.Object,%20java.lang.String%29
Get List of Properties:
http://commons.apache.org/beanutils/api/org/apache/commons/beanutils/BeanUtils.html#describe%28java.lang.Object%29
Lots of other useful methods there, and for UI work they are particularly convenient since many of them return the string form which is what you want to display.
If you want objects rather than strings use the PropertUtils class instead
Get the value of the property (not as a string)
http://commons.apache.org/beanutils/v1.8.3/apidocs/org/apache/commons/beanutils/PropertyUtils.html#getProperty%28java.lang.Object,%20java.lang.String%29
Get list of properties:
http://commons.apache.org/beanutils/v1.8.3/apidocs/org/apache/commons/beanutils/PropertyUtils.html#describe%28java.lang.Object%29