I would like to know, how to make scrollview swipe effect
when mouse is dragged up and down. I'm developing JavaFX application which has ListView
& I need to scroll the list when user drags the mouse up and down (like iOS contact list).
Also how to add the user's dragging velocity and speed to the scrolling value?
UPDATED : I got some code here but It doesn't work properly...
import java.util.ArrayList;
import java.util.Arrays;
import javafx.animation.Interpolator;
import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.animation.TimelineBuilder;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.event.Event;
import javafx.geometry.Pos;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollPane;
import javafx.scene.input.MouseEvent;
import javafx.scene.input.ScrollEvent;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.FlowPane;
import javafx.util.Duration;
public class Swipe extends ScrollPane {
private static final int INERTIA_DURATION = 2400;
private static final double CLICK_THRESHOLD = 20;
private static final double CLICK_TIME_THRESHOLD = Integer.parseInt(System.getProperty("click", "400"));
private final double width;
private final double height;
private long startDrag;
private long lastDrag;
private long lastDragDelta;
private int startDragX;
private int startDragY;
private int lastDragX;
private int lastDragY;
private int lastDragStepX;
private int lastDragStepY;
private double dragVelocityX;
private double dragVelocityY;
private boolean clickThresholdBroken;
private Timeline inertiaTimeline = null;
private long lastClickTime = -1;
private final boolean isFiredByMe = false;
public Swipe(double width, double height) {
this.width = width;
this.height = height;
init();
}
private void init() {
setPrefSize(width, height);
setPannable(true);
setHbarPolicy(ScrollBarPolicy.NEVER);
setVbarPolicy(ScrollBarPolicy.NEVER);
setEventHandlers();
ContentPane cp = new ContentPane();
setContent(cp);
}
private void setEventHandlers() {
setOnMousePressed((MouseEvent event) -> {
lastDragX = startDragX = (int) event.getX();
lastDragY = startDragY = (int) event.getY();
lastDrag = startDrag = System.currentTimeMillis();
lastDragDelta = 0;
if (inertiaTimeline != null) {
inertiaTimeline.stop();
}
clickThresholdBroken = false;
});
setOnDragDetected((MouseEvent event) -> {
// Delta of this drag vs. last drag location (or start)
lastDragStepX = (int) event.getX() - lastDragX;
lastDragStepY = (int) event.getY() - lastDragY;
// Duration of this drag step.
lastDragDelta = System.currentTimeMillis() - lastDrag;
// Velocity of last drag increment.
dragVelocityX = (double) lastDragStepX / (double) lastDragDelta;
dragVelocityY = (double) lastDragStepY / (double) lastDragDelta;
// Snapshot of this drag event.
lastDragX = (int) event.getX();
lastDragY = (int) event.getY();
lastDrag = System.currentTimeMillis();
// Calculate distance so far -- have we dragged enough to scroll?
final int dragX = (int) event.getX() - startDragX;
final int dragY = (int) event.getY() - startDragY;
double distance = Math.abs(Math.sqrt((dragX * dragX) + (dragY * dragY)));
int scrollDistX = lastDragStepX;
int scrollDistY = lastDragStepY;
if (!clickThresholdBroken && distance > CLICK_THRESHOLD) {
clickThresholdBroken = true;
scrollDistX = dragX;
scrollDistY = dragY;
}
if (clickThresholdBroken) {
Event.fireEvent(event.getTarget(), new ScrollEvent(
ScrollEvent.SCROLL,
scrollDistX, scrollDistY,
scrollDistX, scrollDistY,
event.isShiftDown(), event.isControlDown(), event.isAltDown(), event.isMetaDown(),
true, false,
event.getX(), event.getY(),
event.getSceneX(), event.getSceneY(),
ScrollEvent.HorizontalTextScrollUnits.NONE, 0,
ScrollEvent.VerticalTextScrollUnits.NONE, 0, 0, null));
}
});
setOnMouseReleased((MouseEvent event) -> {
handleRelease(event);
});
setOnMouseClicked((MouseEvent event) -> {
final long time = System.currentTimeMillis();
if (clickThresholdBroken || (lastClickTime != -1 && (time - lastClickTime) < CLICK_TIME_THRESHOLD)) {
event.consume();
}
lastClickTime = time;
});
}
private void handleRelease(final MouseEvent me) {
if (clickThresholdBroken) {
// Calculate last instantaneous velocity. User may have stopped moving
// before they let go of the mouse.
final long time = System.currentTimeMillis() - lastDrag;
dragVelocityX = (double) lastDragStepX / (time + lastDragDelta);
dragVelocityY = (double) lastDragStepY / (time + lastDragDelta);
// determin if click or drag/flick
final int dragX = (int) me.getX() - startDragX;
final int dragY = (int) me.getY() - startDragY;
// calculate complete time from start to end of drag
final long totalTime = System.currentTimeMillis() - startDrag;
// if time is less than 300ms then considered a quick flick and whole time is used
final boolean quick = totalTime < 300;
// calculate velocity
double velocityX = quick ? (double) dragX / (double) totalTime : dragVelocityX; // pixels/ms
double velocityY = quick ? (double) dragY / (double) totalTime : dragVelocityY; // pixels/ms
final int distanceX = (int) (velocityX * INERTIA_DURATION); // distance
final int distanceY = (int) (velocityY * INERTIA_DURATION); // distance
//
DoubleProperty animatePosition = new SimpleDoubleProperty() {
double lastMouseX = me.getX();
double lastMouseY = me.getY();
@Override
protected void invalidated() {
final double mouseX = me.getX() + (distanceX * get());
final double mouseY = me.getY() + (distanceY * get());
final double dragStepX = mouseX - lastMouseX;
final double dragStepY = mouseY - lastMouseY;
if (Math.abs(dragStepX) >= 1.0 || Math.abs(dragStepY) >= 1.0) {
Event.fireEvent(me.getTarget(), new ScrollEvent(
ScrollEvent.SCROLL,
dragStepX, dragStepY,
(distanceX * get()), (distanceY * get()),
me.isShiftDown(), me.isControlDown(), me.isAltDown(), me.isMetaDown(),
true, true,
me.getX(), me.getY(),
me.getSceneX(), me.getSceneY(),
ScrollEvent.HorizontalTextScrollUnits.NONE, 0,
ScrollEvent.VerticalTextScrollUnits.NONE, 0,
0, null));
}
lastMouseX = mouseX;
lastMouseY = mouseY;
}
};
// animate a slow down from current velocity to zero
inertiaTimeline = TimelineBuilder.create()
.keyFrames(
new KeyFrame(Duration.ZERO, new KeyValue(animatePosition, 0)),
new KeyFrame(Duration.millis(INERTIA_DURATION), new KeyValue(animatePosition, 1d, Interpolator.SPLINE(0.0513, 0.1131, 0.1368, 1.0000)))
).build();
inertiaTimeline.play();
}
}
private class ContentPane extends FlowPane {
private ArrayList getList() {
String[] list = {
"Kerrie Batts", "Raina Huffstutler", "Kip Kukowski", "Trish Sullivan", "Kyla Hollingsworth", "Gearldine Leavy", "Major Langdon", "Avery Rusin", "Hedy Messina", "Audry Felps", "Tianna Robbins", "Marian Tranmer", "Lashaunda Bivona", "Leighann Schwab", "Emanuel Volpe", "Neida Geist", "Edda Placencia", "Olevia Hippe", "Fernando Cohen", "Danette Dorsett"};
ArrayList<String> nameList = new ArrayList();
nameList.addAll(Arrays.asList(list));
return nameList;
}
public ContentPane() {
setPrefSize(215, 271);
ArrayList<String> nameList = getList();
Element[] element = new Element[nameList.size()];
for (int i = 0; i < nameList.size(); i++) {
String name = nameList.get(i);
Element el = element[i] = new Element(210, 25, name);
getChildren().add(el);
}
}
}
private class Element extends AnchorPane {
private double width;
private double height;
private String name;
public Element(double width, double height, String name) {
this.width = width;
this.height = height;
this.name = name;
init();
}
private Label createName() {
Label label = new Label(name);
label.setPrefSize(width, height);
label.setAlignment(Pos.CENTER_LEFT);
AnchorPane.setLeftAnchor(label, 5.0);
label.setStyle("-fx-font-family: Calibri; -fx-font-size: 14;");
return label;
}
private void init() {
setPrefSize(width, height);
getChildren().add(createName());
}
public void setPrefSize(double width, double height) {
this.width = width;
this.height = height;
}
public void setName(String name) {
this.name = name;
}
}
}