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Simple demo of creating a appointment-calendar like view (similar to the default calendar view in Google Calendar), in JavaFX 8. Just manages selection of time slots in the grid.
.time-slot {
-fx-background-color: black, white ;
-fx-background-insets: 0, 1 1 0 0 ;
}
.time-slot:selected {
-fx-background-color: honeydew ;
}
package calendarview;
import java.time.DayOfWeek;
import java.time.Duration;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.css.PseudoClass;
import javafx.geometry.HPos;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.Region;
import javafx.scene.text.TextAlignment;
import javafx.stage.Stage;
public class CalendarView extends Application {
private final LocalTime firstSlotStart = LocalTime.of(0, 0);
private final Duration slotLength = Duration.ofMinutes(15);
private final LocalTime lastSlotStart = LocalTime.of(23, 59);
private static final PseudoClass SELECTED_PSEUDO_CLASS = PseudoClass.getPseudoClass("selected");
private final List<TimeSlot> timeSlots = new ArrayList<>();
@Override
public void start(Stage primaryStage) {
GridPane calendarView = new GridPane();
ObjectProperty<TimeSlot> mouseAnchor = new SimpleObjectProperty<>();
LocalDate today = LocalDate.now();
LocalDate startOfWeek = today.minusDays(today.getDayOfWeek().getValue() - 1) ;
LocalDate endOfWeek = startOfWeek.plusDays(6);
for (LocalDate date = startOfWeek; ! date.isAfter(endOfWeek); date = date.plusDays(1)) {
int slotIndex = 1 ;
for (LocalDateTime startTime = date.atTime(firstSlotStart);
! startTime.isAfter(date.atTime(lastSlotStart));
startTime = startTime.plus(slotLength)) {
TimeSlot timeSlot = new TimeSlot(startTime, slotLength);
timeSlots.add(timeSlot);
registerDragHandlers(timeSlot, mouseAnchor);
calendarView.add(timeSlot.getView(), timeSlot.getDayOfWeek().getValue(), slotIndex);
slotIndex++ ;
}
}
//headers:
DateTimeFormatter dayFormatter = DateTimeFormatter.ofPattern("E\nMMM d");
for (LocalDate date = startOfWeek; ! date.isAfter(endOfWeek); date = date.plusDays(1)) {
Label label = new Label(date.format(dayFormatter));
label.setPadding(new Insets(1));
label.setTextAlignment(TextAlignment.CENTER);
GridPane.setHalignment(label, HPos.CENTER);
calendarView.add(label, date.getDayOfWeek().getValue(), 0);
}
int slotIndex = 1 ;
DateTimeFormatter timeFormatter = DateTimeFormatter.ofPattern("H:mm");
for (LocalDateTime startTime = today.atTime(firstSlotStart);
! startTime.isAfter(today.atTime(lastSlotStart));
startTime = startTime.plus(slotLength)) {
Label label = new Label(startTime.format(timeFormatter));
label.setPadding(new Insets(2));
GridPane.setHalignment(label, HPos.RIGHT);
calendarView.add(label, 0, slotIndex);
slotIndex++ ;
}
ScrollPane scroller = new ScrollPane(calendarView);
Scene scene = new Scene(scroller);
scene.getStylesheets().add(getClass().getResource("calendar-view.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
}
// Registers handlers on the time slot to manage selecting a range of slots in the grid.
private void registerDragHandlers(TimeSlot timeSlot, ObjectProperty<TimeSlot> mouseAnchor) {
timeSlot.getView().setOnDragDetected(event -> {
mouseAnchor.set(timeSlot);
timeSlot.getView().startFullDrag();
timeSlots.forEach(slot ->
slot.setSelected(slot == timeSlot));
});
timeSlot.getView().setOnMouseDragEntered(event -> {
TimeSlot startSlot = mouseAnchor.get();
timeSlots.forEach(slot ->
slot.setSelected(isBetween(slot, startSlot, timeSlot)));
});
timeSlot.getView().setOnMouseReleased(event -> mouseAnchor.set(null));
}
// Utility method that checks if testSlot is "between" startSlot and endSlot
// Here "between" means in the visual sense in the grid: i.e. does the time slot
// lie in the smallest rectangle in the grid containing startSlot and endSlot
//
// Note that start slot may be "after" end slot (either in terms of day, or time, or both).
// The strategy is to test if the day for testSlot is between that for startSlot and endSlot,
// and to test if the time for testSlot is between that for startSlot and endSlot,
// and return true if and only if both of those hold.
// Finally we note that x <= y <= z or z <= y <= x if and only if (y-x)*(z-y) >= 0.
private boolean isBetween(TimeSlot testSlot, TimeSlot startSlot, TimeSlot endSlot) {
boolean daysBetween = testSlot.getDayOfWeek().compareTo(startSlot.getDayOfWeek())
* endSlot.getDayOfWeek().compareTo(testSlot.getDayOfWeek()) >= 0 ;
boolean timesBetween = testSlot.getTime().compareTo(startSlot.getTime())
* endSlot.getTime().compareTo(testSlot.getTime()) >= 0 ;
return daysBetween && timesBetween ;
}
// Class representing a time interval, or "Time Slot", along with a view.
// View is just represented by a region with minimum size, and style class.
// Has a selected property just to represent selection.
public static class TimeSlot {
private final LocalDateTime start ;
private final Duration duration ;
private final Region view ;
private final BooleanProperty selected = new SimpleBooleanProperty();
public final BooleanProperty selectedProperty() {
return selected ;
}
public final boolean isSelected() {
return selectedProperty().get();
}
public final void setSelected(boolean selected) {
selectedProperty().set(selected);
}
public TimeSlot(LocalDateTime start, Duration duration) {
this.start = start ;
this.duration = duration ;
view = new Region();
view.setMinSize(80, 20);
view.getStyleClass().add("time-slot");
selectedProperty().addListener((obs, wasSelected, isSelected) ->
view.pseudoClassStateChanged(SELECTED_PSEUDO_CLASS, isSelected));
}
public LocalDateTime getStart() {
return start ;
}
public LocalTime getTime() {
return start.toLocalTime() ;
}
public DayOfWeek getDayOfWeek() {
return start.getDayOfWeek() ;
}
public Duration getDuration() {
return duration ;
}
public Node getView() {
return view;
}
}
public static void main(String[] args) {
launch(args);
}
}
@kunal2rock

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@kunal2rock kunal2rock commented Aug 7, 2017

thanks for sharing a nice snippet. It is really very helpful to start from scratch for calendar like applications.

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