Java Swing:鼠标可以同时更改两个重叠的JPanel吗?

时间:2018-01-29 15:31:09

标签: java swing jpanel mouselistener openslide

我是新手,我有以下问题:

我使用openslide-java库来查看整个幻灯片图像。有一个名为OpenSlideView的类可以扩展JPanel,其目的是查看图像。该类具有使用鼠标放大,缩小和导航图像的功能,因为它使用自己的鼠标监听器。我在JFrame中覆盖了两个OpenSlideView对象,其中一个是可见的而另一个是不可见的,我希望能够同时对它们执行鼠标操作,即使其中一个不可见。简单地说,我希望不可见的JPanel跟踪鼠标。

这样的事情可能吗?即使是JPanel类,也不是它的扩展名?

提前致谢。

P.S:我附加了处理OpenSlideView对象鼠标事件的方法代码,以防它有用。

   private void registerEventHandlers() {
    // mouse wheel
    addMouseWheelListener(new MouseWheelListener() {
        public void mouseWheelMoved(MouseWheelEvent e) {
            double ds1 = zoomHelper(OpenSlideView.this, e.getX(), e.getY(),
                    e.getWheelRotation());
            double ds2 = zoomHelper(otherView, e.getX(), e.getY(), e
                    .getWheelRotation());
            zoomHelper2(OpenSlideView.this, ds1, e.getX(), e.getY());
            zoomHelper2(otherView, ds2, e.getX(), e.getY());
            zoomHelper3(OpenSlideView.this, ds1);
            zoomHelper3(otherView, ds2);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    // mouse drag
    MouseAdapter ma = new MouseAdapter() {
        private SelectionMode selectionMode;

        private int oldX;

        private int oldY;

        private int slideStartX;

        private int slideStartY;

        private Path2D.Double freehandPath;

        @Override
        public void mousePressed(MouseEvent e) {
            // System.out.println(e);

            requestFocusInWindow();

            if (!SwingUtilities.isLeftMouseButton(e)) {
                return;
            }

            final int ellipseMask = MouseEvent.CTRL_DOWN_MASK
                    | MouseEvent.SHIFT_DOWN_MASK;
            final int freehandMask = MouseEvent.CTRL_DOWN_MASK;
            final int rectMask = MouseEvent.SHIFT_DOWN_MASK;

            if ((e.getModifiersEx() & ellipseMask) == ellipseMask) {
                selectionMode = SelectionMode.ELLIPSE;
            } else if ((e.getModifiersEx() & freehandMask) == freehandMask) {
                selectionMode = SelectionMode.FREEHAND;
            } else if ((e.getModifiersEx() & rectMask) == rectMask) {
                selectionMode = SelectionMode.RECT;
            } else {
                selectionMode = SelectionMode.NONE;
            }

            oldX = e.getX();
            oldY = e.getY();

            double ds = getDownsample();
            slideStartX = (int) ((oldX + viewPosition.x) * ds);
            slideStartY = (int) ((oldY + viewPosition.y) * ds);
        }

        @Override
        public void mouseDragged(MouseEvent e) {
            if (!SwingUtilities.isLeftMouseButton(e)) {
                return;
            }

            int relX = oldX - e.getX();
            int relY = oldY - e.getY();

            double ds = getDownsample();
            int dx = slideStartX;
            int dy = slideStartY;
            int dw = (int) ((e.getX() + viewPosition.x) * ds) - dx;
            int dh = (int) ((e.getY() + viewPosition.y) * ds) - dy;

            if (dw < 0) {
                dx += dw;
                dw = -dw;
            }
            if (dh < 0) {
                dy += dh;
                dh = -dh;
            }

            switch (selectionMode) {
            case NONE:
                translateHelper(OpenSlideView.this, relX, relY);
                translateHelper(otherView, relX, relY);
                repaintHelper(OpenSlideView.this);
                repaintHelper(otherView);
                break;

            case RECT:
                selectionBeingDrawn = new Rectangle(dx, dy, dw, dh);
                // System.out.println(selection);
                repaint();
                break;

            case FREEHAND:
                if (selectionBeingDrawn == null) {
                    // new selection
                    freehandPath = new Path2D.Double();
                    selectionBeingDrawn = freehandPath;

                    freehandPath.moveTo(slideStartX, slideStartY);
                }

                freehandPath.lineTo((e.getX() + viewPosition.x) * ds, (e
                        .getY() + viewPosition.y)
                        * ds);

                repaint();
                break;

            case ELLIPSE:
                selectionBeingDrawn = new Ellipse2D.Double(dx, dy, dw, dh);

                repaint();
                break;
            }
            oldX = e.getX();
            oldY = e.getY();
        }

        @Override
        public void mouseReleased(MouseEvent e) {
            if (selectionMode == SelectionMode.FREEHAND) {
                freehandPath.closePath();
            }
            selectionMode = SelectionMode.NONE;

            if (selectionBeingDrawn != null) {
                Rectangle bb = selectionBeingDrawn.getBounds();
                if (bb.height != 0 && bb.width != 0) {
                    selections.add(new DefaultAnnotation(selectionBeingDrawn));
                    selectionBeingDrawn = null;
                }
            }
            repaint();
        }

        @Override
        public void mouseEntered(MouseEvent e) {
            selectionsVisibleHelper(OpenSlideView.this, true);
            selectionsVisibleHelper(otherView, true);
        }

        @Override
        public void mouseExited(MouseEvent e) {
            selectionsVisibleHelper(OpenSlideView.this, false);
            selectionsVisibleHelper(otherView, false);
        }
    };
    addMouseListener(ma);
    addMouseMotionListener(ma);

    // keyboard
    InputMap inputMap = new InputMap();
    ActionMap actionMap = new ActionMap();

    inputMap.put(KeyStroke.getKeyStroke("SPACE"), "center");
    actionMap.put("center", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            centerHelper(OpenSlideView.this);
            centerHelper(otherView);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("UP"), "scroll up");
    inputMap.put(KeyStroke.getKeyStroke("W"), "scroll up");
    actionMap.put("scroll up", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            translateHelper(OpenSlideView.this, 0, -KEYBOARD_SCROLL_AMOUNT);
            translateHelper(otherView, 0, -KEYBOARD_SCROLL_AMOUNT);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("DOWN"), "scroll down");
    inputMap.put(KeyStroke.getKeyStroke("S"), "scroll down");
    actionMap.put("scroll down", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            translateHelper(OpenSlideView.this, 0, KEYBOARD_SCROLL_AMOUNT);
            translateHelper(otherView, 0, KEYBOARD_SCROLL_AMOUNT);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("LEFT"), "scroll left");
    inputMap.put(KeyStroke.getKeyStroke("A"), "scroll left");
    actionMap.put("scroll left", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            translateHelper(OpenSlideView.this, -KEYBOARD_SCROLL_AMOUNT, 0);
            translateHelper(otherView, -KEYBOARD_SCROLL_AMOUNT, 0);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("RIGHT"), "scroll right");
    inputMap.put(KeyStroke.getKeyStroke("D"), "scroll right");
    actionMap.put("scroll right", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            translateHelper(OpenSlideView.this, KEYBOARD_SCROLL_AMOUNT, 0);
            translateHelper(otherView, KEYBOARD_SCROLL_AMOUNT, 0);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("L"), "rotate left");
    actionMap.put("rotate left", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {

        }
    });

    inputMap.put(KeyStroke.getKeyStroke("R"), "rotate right");
    actionMap.put("rotate right", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {

        }
    });

    inputMap.put(KeyStroke.getKeyStroke("PLUS"), "zoom in");
    inputMap.put(KeyStroke.getKeyStroke("EQUALS"), "zoom in");
    actionMap.put("zoom in", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            double d1 = zoomHelper(OpenSlideView.this, -1);
            double d2 = zoomHelper(otherView, -1);
            zoomHelper2(OpenSlideView.this, d1);
            zoomHelper2(otherView, d2);
            zoomHelper3(OpenSlideView.this, d1);
            zoomHelper3(otherView, d2);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("MINUS"), "zoom out");
    actionMap.put("zoom out", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            double d1 = zoomHelper(OpenSlideView.this, 1);
            double d2 = zoomHelper(otherView, 1);
            zoomHelper2(OpenSlideView.this, d1);
            zoomHelper2(otherView, d2);
            zoomHelper3(OpenSlideView.this, d1);
            zoomHelper3(otherView, d2);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("Z"), "zoom to fit");
    actionMap.put("zoom to fit", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            // System.out.println("zoom");
            zoomToFit();
            centerSlidePrivate();
            paintBackingStore();
            repaint();
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("1"), "zoom to 1:1");
    actionMap.put("zoom to 1:1", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            // System.out.println("zoom 1:1");
            double d1 = zoomHelper(OpenSlideView.this, Integer.MIN_VALUE);
            double d2 = zoomHelper(otherView, Integer.MIN_VALUE);
            zoomHelper2(OpenSlideView.this, d1);
            zoomHelper2(otherView, d2);
            zoomHelper3(OpenSlideView.this, d1);
            zoomHelper3(otherView, d2);
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    inputMap.put(KeyStroke.getKeyStroke("BACK_QUOTE"), "toggle pins");
    actionMap.put("toggle pins", new AbstractAction() {
        public void actionPerformed(ActionEvent e) {
            selectionsAsPins = !selectionsAsPins;
            if (otherView != null) {
                otherView.selectionsAsPins = !otherView.selectionsAsPins;
            }
            repaintHelper(OpenSlideView.this);
            repaintHelper(otherView);
        }
    });

    // install as parents
    InputMap oldInputMap = getInputMap();
    ActionMap oldActionMap = getActionMap();
    inputMap.setParent(oldInputMap.getParent());
    oldInputMap.setParent(inputMap);
    actionMap.setParent(oldActionMap.getParent());
    oldActionMap.setParent(actionMap);
}

2 个答案:

答案 0 :(得分:1)

  

我希望能够同时对它们进行鼠标操作

没有任何意义。如果组件不可见,您为什么要这样做。也许你需要让你的组件保持其当前状态。因此,当您更改顶部组件的状态时,您将更新隐藏组件的状态。如果隐藏的组件变得可见,它将自动以当前状态绘制。

  

简单地说,我希望不可见的JPanel跟踪鼠标。

仅将事件分派给单个组件。

但是,您可以使用Component.dispatchEvent(...)方法将新事件分派给单独的组件。

答案 1 :(得分:0)

是的,你可以这样做,但你需要一个不同的设计。

首先,请注意the API docs's characterization of MouseEvents

  

指示组件中发生鼠标操作的事件。   如果和,则认为鼠标操作发生在特定组件中   只有当鼠标光标位于未经遮挡的部分时   动作发生时组件的界限。对于轻量级组件,   比如Swing的组件,只发送鼠标事件   组件(如果已在组件上启用鼠标事件类型)。   [...] 如果鼠标事件类型没有   已在组件上启用,相应的鼠标事件是   调度到已启用鼠标事件的第一个祖先   类型。

(强调补充。)

因此,当您的某个面板位于另一个面板后面 - 并因此模糊 - 鼠标事件不会出现在模糊部分中。此外,虽然文档没有用很多单词说出来,但你应该从中得到的是MouseEvents被传递给它们自身发生的组件,或者它接受鼠标的包容树中最近的祖先事件。 Swing不会将事件分派给组件,例如模糊的面板,这些组件不是发生事件的组件的包含祖先。

那么,如何使兄弟姐妹或表兄弟成员对同样的鼠标事件做出回应?至少有两种选择:

  1. 在最近的共享祖先容器上注册各种鼠标侦听器,而不是在面板本身上注册。确保面板配置为自己接收鼠标事件。在事件发生时,让在祖先注册的监听器通知小组。

  2. 使用知道所有面板的单个侦听器对象。在每个面板上注册一个对象,并对每个面板采取适当的操作。

  3. 你会注意到那些实际上并没有太大的不同。共同的主题是,只有一个监听器将从Swing接收事件,它将指示相应的面板进行所需的响应。