I have a controller with a string variable, and I would like the text value of a TextArea to change when the controller's string variable changes.
class MyView: View() {
...
button("Run Test").action {
runAsync {
for(test in testList){
controller.updateText = "running" + test.name
run(test)
}
}
}
...
scriptRanArea = textarea {
text = controller.updateText
}
...
}
This is the fastest way I know how to accomplish this, but I don't really know which design pattern you want to use:
class MyView: View() {
val controller: MyController by inject()
override val root = vbox {
textarea(controller.myTextProperty)
}
}
class MyController: Controller() {
val myTextProperty = SimpleStringProperty()
}
The inject method automatically finds the controller within the TornadoFX Scope, or creates one if not found, when it is first referenced. The TornadoFX text area builder function binds the string property from the controller to the TextArea when it is passed in as a param. Keep in mind though, writing in the text area will now automatically change the value in the controller's property and vice versa. If you don't want that functionality, you will have to update your question to be more specific to your needs.
Related
I'm writing a very simple TornadoFX table demo, trying to display the properties of some pojos in a table, but the cells are all empty.
The main code is:
data class User(val id: Int, val name: String)
private val data = listOf(User(111, "AAA"), User(222, "BBB"), User(333, "CCC"), User(444, "DDD")).observable()
class HelloWorld : View() {
override val root = vbox {
tableview(data) {
column("id", User::id.getter)
column("name", User::name.getter)
}
}
}
I use User::id.getter to make it compiling, but the cells are empty.
I did a lot of search, but can't find code to work with current latest tornado (1.7.16)
Here is a complete demo for this: https://github.com/javafx-demos/tornadofx-table-show-pojo-demo
You need to reference the property, not the getter, ie. User::id. To reference immutable properties you need to use the readonlyColumn builder:
readonlyColumn("id", User::id)
readonlyColumn("name", User::name)
That said, you really should use JavaFX properties in your domain objects instead. Not doing so in a JavaFX based application just makes everything harder, and you loose out on a lot of benefits, or at the very least you have to jump through hoops.
Here is the complete application written with observable JavaFX properties. Note that you would then access the idProperty and nameProperty properties instead. With this approach, changes to the underlying data item would automatically be visible in the tableview as well:
class User(id: Int, name: String) {
val idProperty = SimpleIntegerProperty(id)
var id by idProperty
val nameProperty = SimpleStringProperty(name)
var name by nameProperty
}
private val data = listOf(User(111, "AAA"), User(222, "BBB"), User(333, "CCC"), User(444, "DDD")).observable()
class HelloWorld : View() {
override val root = vbox {
tableview(data) {
column("id", User::idProperty)
column("name", User::nameProperty)
}
}
}
I use kotlinx.serialization for my models.
I'd like the idea of them to not depend on JavaFX, so they do not expose properties.
Given a model, I want a tableview for a quick representation of a list of instances, and additionally a more detailed Fragment as an editor.
consider the following model:
#Serializable
data class Person(
var name: String,
var firstname: String,
var complex: Stuff)
the view containing the tableview contains
private val personlist = mutableListOf<Person>().observable()
with a tableview that opens an instance of PersonEditor for the selected row when Enter is pressed:
tableview(personlist) {
column("name", Person::name)
column("first name", Person::firstname)
setOnKeyPressed { ev ->
selectedItem?.apply {
when (ev.code) {
KeyCode.ENTER -> PersonEditor(this).openModal()
}
}
}
}
I followed this gitbook section (but do not want the modelview to be rebound on selection of another row within the tableview)
The editor looks about like this:
class PersonEditor(person: Person) : ItemFragment<Person>() {
val model: Model = Model()
override val root = form {
fieldset("Personal information") {
field("Name") {
textfield(model.name)
}
field("Vorname") {
textfield(model.firstname)
}
}
fieldset("complex stuff") {
//... more complex stuff here
}
fieldset {
button("Save") {
enableWhen(model.dirty)
action { model.commit() }
}
button("Reset") { action { model.rollback() } }
}
}
class Model : ItemViewModel<Person>() {
val name = bind(Person::name)
val firstname = bind(Person::firstname)
//... complex stuff
}
init {
itemProperty.value = mieter
model.bindTo(this)
}
}
When I save the edited values in the detail view, the tableview is not updated.
Whats the best practize to solve this?
Also I'm unsure, if what I'm doing can be considered good practize, so i'd be happy for some advice on that too.
The best practice in a JavaFX application is to use observable properties. Not doing so is an uphill battle. You can keep your lean domain objects, but add a JavaFX/TornadoFX specific version with observable properties. This object can know how to copy data to/from your "lean" domain objects.
With this approach, especially in combination with ItemViewModel wrappers will make sure that your data is always updated.
The setOnKeyPressed code you posted can be changed to:
setOnUserSelect {
PersonEditor(it).openModal()
}
Notice though, that you are not supposed to instantiate Views and Fragments directly, as doing so skips certain steps in the TornadoFX life cycle. Instead you should pass the person as a parameter, or create a new scope and inject a PersonModel into that scope before opening the editor in that scope:
setOnUserSelect {
find<PersonEditor>(Scope(PersonEditor(it)))
}
I have the following code:
class ExampleView :View("My Example view") {
val model:ExampleModel by inject()
override val root= vbox {
textfield(model.data)
button("Commit") {
setOnAction {
model.commit()
closeModal()
}
}
button("Rollback") {
setOnAction {
model.rollback()
closeModal()
}
}
button("Just quit") {
setOnAction {
closeModal()
}
}
}
}
class Example() {
var data by property<String>()
fun dataProperty() = getProperty(Example::data)
}
class ExampleModel(example: Example) : ItemViewModel<Example>() {
init {
item = example
}
val data = bind { item?.dataProperty() }
}
class MainView : View() {
val example:Example
override val root = BorderPane()
init {
example = Example()
example.data = "Data for example"
val exampleModel = ExampleModel(example)
with(root){
top {
menubar {
menu("Test") {
menuitem("Example - 1") {
val scope = Scope()
setInScope(exampleModel, scope)
find<ExampleView>(scope).openWindow()
}
menuitem("Example - 2") {
val scope = Scope()
setInScope(exampleModel, scope)
find<ExampleView>(scope).openWindow()
}
}
}
}
}
}
}
I have two questions for this example:
1) If i change the value and close the window without a commit (User can do this with help [X] button) then only ViewModel will store changes (and it will be displayed in GUI even after the re-opening ), but model POJO object will keep the old data.
if I used instance of Example class (without DI) then this instance received all the changes at once.
For example i don't want commit/rollback functionality but i want DI and immediate updating. What i should do? (ofcource i can call "commit" for "textfield change value event")
2) ViewModel has constructor with parameter and if i try open ExampleView like this
find<ExampleView>(Scope()).openWindow()
then I got an an obvious RuntimeException. Can I avoid this for example, by a compiler warnings (or by something else)?
1) This is the correct default behavior of the ViewModel. If you bind a property of the view model to an input, the changes are immediately reflected in that bound property, but will only be flushed into the underlying model object once you commit it.
If you want to autocommit changes in the view model properties back into the underlying model object, you can create the binding with the autocommit property set to true:
val data = bind(true) { item?.dataProperty() }
You can also write bind(autocommit = true) if that looks clearer to you. This will cause any changes to be automatically flushed back into the underlying object.
I also want to make you aware that by requiring an item in the constructor of your view model, you're effectively preventing it from being used with injection unless you prime it like you do using setInScope. This might be fine for your use case, but worth noting.
2) The upcoming TornadoFX 1.5.10 will give you a better runtime error message if you forget to pass a parameter. It also introduces default values for parameters. See https://github.com/edvin/tornadofx/pull/227 for more info.
I have been reading about properties in Kotlin, including custom getters and setters.
However, I was wondering if it is possible to create a custom getter with extra parameters.
For example, consider the following method in Java:
public String getDisplayedValue(Context context) {
if (PrefUtils.useImperialUnits(context)) {
// return stuff
} else {
// return other stuff
}
}
Note that the static method in PrefUtils has to have Context as a parameter, so removing this is not an option.
I would like to write it like this in Kotlin:
val displayedValue: String
get(context: Context) {
return if (PrefUtils.useImperialUnits(context)) {
// stuff
} else {
// other stuff
}
}
But my IDE highlights all of this in red.
I am aware I can create a function in my class to get the displayed value, but this would mean I would have to use .getDisplayedValue(Context) in Kotlin as well instead of being able to refer to the property by name as in .displayedValue.
Is there a way to create a custom getter like this?
EDIT: If not, would it be best to write a function for this, or to pass Context into the parameters of the class constructor?
As far as I know, property getter cannot have parameter. Write a function instead.
You can do this by having a property that returns an intermediate object that has a get and/or set operator with the parameters that you want, rather than returning the value directly.
Having that intermediate object be an inner class instance may be useful for providing easy access to the parent object. However, in an interface you can't use inner classes so in that case you might need to provide an explicit constructor parameter referencing the parent object when constructing your intermediate object.
For instance:
class MyClass {
inner class Foo {
operator fun get(context: Context): String {
return if (PrefUtils.useImperialUnits(context)) {
// return stuff
} else {
// return other stuff
}
}
}
val displayedValue = Foo()
}
...
val context : Context = whatever
val mc : MyClass = whatever
val y: String = mc.displayedValue[context]
You can do for example:
val displayedValue: String by lazy {
val newString = context.getString(R.string.someString)
newString
}
When I try to override a property I get an error "can not override mutable property with read-only property"
I have provided get and set in the super class.
class Card {
var contents:String {
get {
return self.contents
}
set {
self.contents = newValue
}
}
init() {
self.contents = ""
}
}
Here is my Subclass where I am trying to override the "contents" property.
class PlayingCard: Card {
override var contents:String { //<-- this is where I get the build error
get {
var rankStrings:Array<String> = PlayingCard.rankStrings()
return rankStrings[Int(self.rank)] + self.suit
}
}
}
What exactly am I doing wrong?
If the property you're overriding has both a getter and a setter, you need to provide both in your subclass as well. Here's the relevant part from the Swift language guide (emphasis mine):
You can present an inherited read-only property as a read-write
property by providing both a getter and a setter in your subclass
property override. You cannot, however, present an inherited
read-write property as a read-only property.
If you're not doing anything special with the value, then you'll typically want to pass the value being set on to the base class:
set {
super.contents = newValue
}
You could also just discard the value with an empty setter (although I can't think of a good reason to do this offhand):
set { }
I also wanted to point out that you have an infinite loop in the contents property in your Card class. When you you do this:
get {
return self.contents
}
You're actually just calling that same getter again, creating an infinite loop; you're doing the same with the setter. Swift doesn't create ivars for your properties automatically like Objective-C did, so you need to create them yourself. A more appropriate way to create that property would be to do something like this:
class Card {
private var _contents: String
var contents: String {
get {
return _contents
}
set {
_contents = newValue
}
}
init() {
_contents = ""
}
}
However, since you're not doing anything other than setting and returning _contents in your setter and getter, you can simplify it down to this:
class Card {
var contents: String = ""
init() {
}
}
Note: contents might also be a good candidate for using an optional (String?) and setting it to nil rather than initializing it to an empty string.
The compiler error message is fairly straightforward: Card's contents property is mutable, which is to say it has a set method in addition to the get method.
Your override only adds a get method, you need to add a set method too.
I think this is what you want:
set(newValue) {
rankStrings[Int(self.rank)] = newValue;
}