have a listview and i would like to go to a new activity from every list item
You can try below code snippet
lv.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapter, View v, int position,
long arg3)
{
// do what you intend to do on click of listview row
}
});
Related
To provide some context, I'm writing a Xamarin.Forms application and utilizing data binding with INotifyPropertyChanged. Currently I have an inventory counter displayed on a button. The text on this button displays the bounded "Count" variable (e.g Current Inventory: 35). When I press the button, I push a screen onto the navigation stack which allows me to edit this "Count" variable. I use the class implementation like this
public class UserInventory : INotifyPropertyChanged
{
private int count = 0;
// Declare the event
public event PropertyChangedEventHandler PropertyChanged;
public int Count
{
get => Preferences.Get(nameof(Count),0);
set
{
if (count == value || value <1)
return;
Preferences.Set(nameof(Count), value);
//count = value;
//Application.Current.Properties["Count"] = count;
OnPropertyChanged(nameof(Count));
//OnPropertyChanged(nameof(displayName));
}
}
public UserInventory()
{
}
void OnPropertyChanged(string count)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(count));
}
}
I add this class in Xaml according to the tutorial on the Xamarin <ContentPage.BindingContext>
<local:UserInventory />
</ContentPage.BindingContext>
So the variables are bounded correctly and I have no issues seeing updates on the current page or when I push new pages. The issue is when I swipe back on iOS the previous screen with the button "Current Inventory: 35" does not update to reflect the new changes. If I push that screen the changes are reflected.
Is there anyway to ensure the bounded data is updated when you go back (PopAsync()) ?
Try overriding page's OnAppearing() method and call OnPropertyChanged from there.
Assuming 'UserInventory' the binded VM.....
public partial class Page1:ContentPage
{
public Page1()
{
InitializeComponent();
VM = (UserInventory)BindingContext;
}
public UserInventory VM { get; }
protected override void OnAppearing()
{
VM.Notify();
base.OnAppearing();
}
}
.
public class UserInventory: INotifyPropertyChanged
{
........
public void Notify()
{
OnPropertyChanged(nameof(Count));
}
}
i have a lot of HBoxes with some different components inside ( RadioButton, Labels, Buttons ...).
The RadioButtons are in a ToggleGroup, so only 1 Radio Button can be selected.
I want to add a OnChange - Event to the Radio Button. If the RadioButton would be unselected there should be a Event-Trigger. How can i add the Event to the Radio-Button?
At the moment i have a code like this, but it doesn't have the function i want to have.
radio.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
if(!radio.isSelected()){
ivTriangleImg.setRotate(iRotateCoord2);
btnTriangle.setGraphic(ivTriangleImg);
}
if(group!=null){
group.selectedToggleProperty().addListener(new ChangeListener<Toggle>() {
#Override
public void changed(
ObservableValue<? extends Toggle> arg0,
Toggle arg1, Toggle arg2) {
}
});
}
}
});
I use JavaFX 2.0 and Java 1.7 so i can not use Lambda Functions or the special component functions of JavaFx8 / Java 1.8
The state of JavaFX controls is represented by observable properties. You can access these properties with control.propertyNameProperty() and add ChangeListeners to them:
radioButton.selectedProperty().addListener(new ChangeListener<Boolean>() {
#Override
public void changed(ObservableValue<? extends Boolean> obs, Boolean wasPreviouslySelected, Boolean isNowSelected) {
if (isNowSelected) {
// ...
} else {
// ...
}
}
});
radio.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
if(!radio.isSelected()){
ivTriangleImg.setRotate(iRotateCoord2);
btnTriangle.setGraphic(ivTriangleImg);
}
if(group!=null){
group.selectedToggleProperty().addListener(new ChangeListener<Toggle>() {
#Override
public void changed(
ObservableValue<? extends Toggle> arg0,
Toggle arg1, Toggle arg2) {
if(!radio.isSelected()&&ivTriangleImg.getRotate()!=iRotateCoord1){
ivTriangleImg.setRotate(iRotateCoord1);
btnTriangle.setGraphic(ivTriangleImg);
}
}
});
}
}
});
This would work for my Question. I have done a little mistake, so i don't check the Radio-Style. It works fine now... Sorry for this Question.
Is there a possibility to check the Event at the Radio Button and not at his group?
In case you have many radio buttons you dont want have a single EventHandlers for each one of them....
Here is an example with 6 radio buttons but just one ChangeListener where the events are all process in a centralized method.
This detects programatic events, keyboard events and mouse events
Note that the listener is added to the ToggleGroup
public class ReportOptionsPane extends BorderPane implements ChangeListener<Toggle> {
RadioButton radioFoldersOnly ;
RadioButton radioAllItems ;
RadioButton radioArtifactsOnly ;
RadioButton radioStatsOrderByOccurrence ;
RadioButton radioStatsOrderByName ;
public ReportOptionsPane(ReportOptions rep) {
super() ;
ToggleGroup tg = new ToggleGroup();
radioFoldersOnly = new RadioButton("Folders only") ;
radioAllItems = new RadioButton("Files & Folders") ;
radioArtifactsOnly = new RadioButton("Artifacts only") ;
radioFoldersOnly.setToggleGroup(tg);
radioAllItems.setToggleGroup(tg);
radioArtifactsOnly.setToggleGroup(tg);
//You add the listener to the toogle group of your radio buttons
tg.selectedToggleProperty().addListener(this);
ToggleGroup tg2 = new ToggleGroup();
radioStatsOrderByOccurrence = new RadioButton("Order stats by occurrence") ;
radioStatsOrderByName = new RadioButton("Order stats by name") ;
radioStatsOrderByOccurrence.setToggleGroup(tg2);
radioStatsOrderByName.setToggleGroup(tg2);
//You can reuse the listener for the second toogle group of your radio buttons
tg2.selectedToggleProperty().addListener(this);
}
//Then you handle all in a centralized place
#Override
public void changed(ObservableValue<? extends Toggle> observable, Toggle oldValue, Toggle newValue) {
if(newValue.equals(radioFoldersOnly)) {
//react to radio button being selected
} else if(newValue.equals(radioAllItems)) {
//react to radio button being selected
} else if(newValue.equals(radioArtifactsOnly)) {
//react to radio button being selected
} else if(newValue.equals(radioStatsOrderByName)) {
//react to radio button being selected
} else if(newValue.equals(radioStatsOrderByOccurrence) {
//react to radio button being selected
}
}
}
I am trying to catch the events on the JavaFX Slider especially the one which indicates that the drag stopped and was released. At first I used the valueProperty with mock-up code like this
slider.valueProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> ov, Number oldValue, Number newValue) {
log.fine(newValue.toString());
}
});
but with this it update too often. So I searched within SceneBuilder and the API and found some interessting like
slider.setOnMouseDragReleased(new EventHandler<MouseDragEvent>() {
#Override
public void handle(MouseDragEvent event) {
System.out.println("setOnMouseDragReleased");
}
});
but they never get fired. There only some like setOnMouseReleased I get some output, but this for example count for the whole Node like the labels etc.
So my question is, which is the correct hook to know the value is not changing anymore (if possible after release of the mouse like drag'n'drop gesture) and maybe with a small example to see its interfaces working.
Add a change listener to the slider's valueChangingProperty to know when the slider's value is changing, and take whatever action you want on the value change.
The sample below will log the slider's value when it starts to change and again when it finishes changing.
import javafx.application.Application;
import javafx.beans.value.*;
import javafx.geometry.*;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;
public class SliderChangeLog extends Application {
private final ListView<String> startLog = new ListView<>();
private final ListView<String> endLog = new ListView<>();
#Override public void start(Stage stage) throws Exception {
Pane logsPane = createLogsPane();
Slider slider = createMonitoredSlider();
VBox layout = new VBox(10);
layout.setAlignment(Pos.CENTER);
layout.setPadding(new Insets(10));
layout.getChildren().setAll(
slider,
logsPane
);
VBox.setVgrow(logsPane, Priority.ALWAYS);
stage.setTitle("Slider Value Change Logger");
stage.setScene(new Scene(layout));
stage.show();
}
private Slider createMonitoredSlider() {
final Slider slider = new Slider(0, 1, 0.5);
slider.setMajorTickUnit(0.5);
slider.setMinorTickCount(0);
slider.setShowTickMarks(true);
slider.setShowTickLabels(true);
slider.setMinHeight(Slider.USE_PREF_SIZE);
slider.valueChangingProperty().addListener(new ChangeListener<Boolean>() {
#Override
public void changed(
ObservableValue<? extends Boolean> observableValue,
Boolean wasChanging,
Boolean changing) {
String valueString = String.format("%1$.3f", slider.getValue());
if (changing) {
startLog.getItems().add(
valueString
);
} else {
endLog.getItems().add(
valueString
);
}
}
});
return slider;
}
private HBox createLogsPane() {
HBox logs = new HBox(10);
logs.getChildren().addAll(
createLabeledLog("Start", startLog),
createLabeledLog("End", endLog)
);
return logs;
}
public Pane createLabeledLog(String logName, ListView<String> log) {
Label label = new Label(logName);
label.setLabelFor(log);
VBox logPane = new VBox(5);
logPane.getChildren().setAll(
label,
log
);
logPane.setAlignment(Pos.TOP_LEFT);
return logPane;
}
public static void main(String[] args) { launch(args); }
}
There could be times when you want to know when the user is moving the slider versus the slider value changing due to a binding to a property. One example is a slider that is used on a media player view to show the media timeline. The slider not only displays the time but also allows the user to fast forward or rewind. The slider is bound to the media player's current time which fires the change value on the slider. If the user moves the slider, you may want to detect the drag so as to stop the media player, have the media player seek to the new time and resume playing. Unfortunately the only drag event that seems to fire on the slider is the setOnDragDetected event. So I used the following two methods to check for a slider drag.
slider.setOnDragDetected(new EventHandler<Event>() {
#Override
public void handle(Event event) {
currentPlayer.pause();
isDragged=true;
}
});
slider.setOnMouseReleased(new EventHandler<Event>() {
#Override
public void handle(Event event) {
if(isDragged){
currentPlayer.seek(Duration.seconds((double) slider.getValue()));
currentPlayer.play();
isDragged=false;
}
}
});
jewelsea's answer was very helpful for setting me on the right track, however if "snapToTicks" is on, undesired behavior results. The "end" value as captured by jewelsea's listener is before the snap takes place, and the post-snap value is never captured.
My solution sets a listener on value but uses valueChanging as a sentinel. Something like:
slider.valueProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(
ObservableValue<? extends Number> observableValue,
Number previous,
Number now) {
if (!slider.isValueChanging()
|| now.doubleValue() == slider.getMax()
|| now.doubleValue() == slider.getMin()) {
// This only fires when we're done
// or when the slider is dragged to its max/min.
}
}
});
I found that checking for the max and min value was necessary to catch the corner case where the user drags the slider all the way past its left or right bounds before letting go of the mouse. For some reason, that doesn't fire an event like I'd expect, so this seems like an okay work-around.
Note: Unlike jewelsea, I'm ignoring the starting value for the sake of simplicity.
Note 2: I'm actually using ScalaFX 2, so I'm not sure if this Java translation compiles as-written.
I would like to start editing after adding new row into TableView.
I copied example from Oracle website: Using JavaFX UI Controls - 13 Table View. Then I put additional button for adding new row and define action for the button.
final Button addButton = new Button("Add");
addButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
Person p = new Person("", "", "");
table.getItems().add(p);
table.getSelectionModel().select(p);
table.edit(table.getSelectionModel().getSelectedIndex(), table.getColumns().get(2));
}
});
In result I can see selected new row but the table doesn't start edditing in the third column.
I have similar method for editing existing rows and it works properly.
final Button editButton = new Button("Edit");
editButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent arg0) {
table.edit(table.getSelectionModel().getSelectedIndex(), table.getColumns().get(2));
}
});
Could you help me what I do wrong?
My application using a 'vertical field' manager and i add some text to it using a custonField class.The vertical manager constructor is:
scrollingRegion = new VerticalFieldManager(
USE_ALL_HEIGHT| VERTICAL_SCROLL | VERTICAL_SCROLLBAR|USE_ALL_WIDTH);
I also craete menu using:
protected void makeMenu(Menu menu, int context) {
menu.add(_imageMenuItem);
//super.makeMenu(menu, context);
}
class ImageMenuItem extends MenuItem {
/**
* Creates a new MenuDemoMenuItem object
*/
ImageMenuItem() {
super("Login Screen", 0, 0);
}
public boolean onMenu(int i) {
return false;
}
public void run() {
UiApplication app = (UiApplication) getApplication();
app.pushScreen(new LoginScreen());
}
}
My problem is when I click in the vertical field(which uses a table row manager), the menu is displayed. How can I avoid it? Can any one suggest a solution
if the item is ButtonField you can consume click by define it in the constructor
ButtonField btn = new ButtonField("Login", ButtonField.CONSUME_CLICK);