Creating a drag-less component in Swing

Question

And the JComponentevent excites me mouseDraggedtoo energetically. When a user tries to click, it is interpreted as a drag and drop, even if the mouse only moved 1 pixel.

How to add a rule for a specific component, which amounted to:

Do not consider this a drag event if the mouse has moved 10 pixels from the point at which the button was clicked.

Note. I know that this is not a system parameter in my OS, since only events on this component suffer from this excessive sensitivity.

Thanks.

Answer 1

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public void mousePressed(int mod, Point loc) {
    pressLocation=copyLocation(loc,pressLocation);
    dragLocation=null;
    }

public void mouseReleased(int mod, Point loc) {
    if(pressLocation!=null && dragLocation!=null) {
        // Mouse drag reverted to mouse click - not dragged far enough
        // action for click
        pressLocation=null;
        }
    else if(dragLocation!=null) {
        // action for drag completed
        }
    else {
        // do nothing
        }

    pressLocation=null;
    dragLocation=null;
    }

public void mouseDragged(int mod, Point loc) {
    if(pressLocation!=null) {                                                   // initial drag actions following mouse press
        dragLocation=pressLocation;                                             // consider dragging to be from start point
        if(Math.abs(loc.x-pressLocation.x)<dragMinimum && Math.abs(loc.y-pressLocation.y)<dragMinimum) {
            return;                                                             // not dragged far enough to count as drag (yet)
            }
        // action drag from press location
        pressLocation=null;
        }
    else {
        // action drag from last drag location
        dragLocation=copyLocation(loc,dragLocation);
        }
    }

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Answer 2

:

public class DragInsensitiveMouseClickListener implements MouseInputListener {

    protected static final int MAX_CLICK_DISTANCE = 15;

    private final MouseInputListener target;

    public MouseEvent pressed;

    public DragInsensitiveMouseClickListener(MouseInputListener target) {
        this.target = target;
    }

    @Override
    public final void mousePressed(MouseEvent e) {
        pressed = e;
        target.mousePressed(e);
    }

    private int getDragDistance(MouseEvent e) {
        int distance = 0;
        distance += Math.abs(pressed.getXOnScreen() - e.getXOnScreen());
        distance += Math.abs(pressed.getYOnScreen() - e.getYOnScreen());
        return distance;
    }

    @Override
    public final void mouseReleased(MouseEvent e) {
        target.mouseReleased(e);

        if (pressed != null) {
            if (getDragDistance(e) < MAX_CLICK_DISTANCE) {
                MouseEvent clickEvent = new MouseEvent((Component) pressed.getSource(),
                        MouseEvent.MOUSE_CLICKED, e.getWhen(), pressed.getModifiers(),
                        pressed.getX(), pressed.getY(), pressed.getXOnScreen(), pressed.getYOnScreen(),
                        pressed.getClickCount(), pressed.isPopupTrigger(), pressed.getButton());
                target.mouseClicked(clickEvent);
            }
            pressed = null;
        }
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        //do nothing, handled by pressed/released handlers
    }

    @Override
    public void mouseEntered(MouseEvent e) {
        target.mouseEntered(e);
    }

    @Override
    public void mouseExited(MouseEvent e) {
        target.mouseExited(e);
    }

    @Override
    public void mouseDragged(MouseEvent e) {
        if (pressed != null) {
            if (getDragDistance(e) < MAX_CLICK_DISTANCE) return; //do not trigger drag yet (distance is in "click" perimeter
            pressed = null;
        }
        target.mouseDragged(e);
    }

    @Override
    public void mouseMoved(MouseEvent e) {
        target.mouseMoved(e);
    }
}

Answer 3

, click mousedrag. mousedown, mousedrag, , ? , / reset JComponent.

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Answer 4

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navigationTree.addMouseListener(new DragInsensitiveMouseClickListener(10) {
    @Override
    public void mouseClicked(MouseEvent e) {
        TreePath treePath = navigationTree.getPathForLocation(e.getX(), e.getY());

        if(treePath != null) {
            processChoice();
        }
    }
});

mouseClicked(), 10 "".

:

import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

public class DragInsensitiveMouseClickListener extends MouseAdapter {

    private final int allowedTravel;

    public Point mouseDownPoint;

    public DragInsensitiveMouseClickListener(int allowedTravel) {
        this.allowedTravel = allowedTravel;
    }

    @Override
    public void mousePressed(MouseEvent e) {
        mouseDownPoint = e.getPoint();
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        double horizontalTravel = Math.abs(mouseDownPoint.getX() - e.getX());
        double verticalTravel = Math.abs(mouseDownPoint.getY() - e.getY());

        if (horizontalTravel < allowedTravel && verticalTravel < allowedTravel) {
            mouseClicked(e);
        }
    }
}