Java的。拖曳将ImageIcon从面板1上的JLabel拖放到面板上的JLabel 2.添加计数器功能 [英] Java. Drag & Drop ImageIcon from JLabel on panel 1, to JLabel on panel 2. Add Counter function

问题描述

我已经实现了两个JPanels之间的这个非常基本的拖放功能，但这并不能真正满足我的要求。

I've implemented this very basic, drag and drop between two JPanels, but this doesn't really meet my requirements!

public class test extends JFrame {

{    JPanel mainpanel, storypanel, imageselect;



    public test(){

          mainpanel = new JPanel(new BorderLayout());
          storypanel = new JPanel();
          imageselect = new JPanel();
            MouseListener listener = new MouseAdapter(){
            public void mousePressed(MouseEvent e)
        {
            JComponent c = (JComponent) e.getSource();
            TransferHandler handler = c.getTransferHandler();
            handler.exportAsDrag(c, e, TransferHandler.COPY);
        }
        };

            int j = 0;
            BufferedImage myImages;
            JLabel imgselect = new JLabel();
            try { myImages = ImageIO.read(new File("four.jpg"));
            //myImages[j] = resize(myImages[j]);
            imgselect= new JLabel(new ImageIcon(myImages));
            System.out.println(j);
            imageselect.add(imgselect);
            imgselect.addMouseListener(listener);
            imgselect.setTransferHandler(new TransferHandler("icon"));

            } catch(Exception e) {};

            int i = 0;
            BufferedImage storyimages;
            JLabel storylabel = new JLabel();


            //targetImg = new ImageIcon("lmkpackage/base/TargetImg.jpg");
            try{ storyimages = ImageIO.read(new File("TargetImg.jpg"));
            //storyimages[i] = resize(storyimages[i]);
            storylabel = new JLabel(new ImageIcon(storyimages));
            System.out.println(i);
            storypanel.add(storylabel); 
            storylabel.addMouseListener(listener);
            storylabel.setTransferHandler(new TransferHandler("icon"));
            } catch(Exception e) {};


            mainpanel.add(imageselect, BorderLayout.NORTH);
            mainpanel.add(storypanel, BorderLayout.SOUTH);

            getContentPane().add(mainpanel);



        }

        public static void main(String[] args){

        System.out.println("Application Running");
        JFrame mainframe =  new test();
            mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainframe.setSize(1000,1000);
            mainframe.setVisible(true);

        }

    }

对不起我wasn这里很清楚我试图将ImageIcon从图像选择面板上的JLabel拖动到另一个JLabel故事情节面板。我可以用上面的代码来做到这一点。
但是当我这样做时，我可以从imageselect面板拖动一个ImageIcon，并在同一个面板上替换另一个ImageIcon。我不想要这样做。我也可以从故事情节面板拖动到图像选择面板，我不想要。

Sorry I wasn't very clear here. Im trying to drag an ImageIcon from a JLabel on the imageselect panel, to another JLabel the storyline panel. I can do this, with the above code. But when I do this, I can drag an ImageIcon from the imageselect panel, and replace another ImageIcon on the same panel. I do NOT want this to happen. I can also drag from the storyline panel to the imageselect panel, which I do NOT want.

我不是要求勺子代码，我只是看为了推动正确的方向！

I'm not asking to be spoon fed code, I'm just looking for a push in the right direction!

编辑：我想知道有没有办法计算一个成功的拖放操作，下面的解决方案回答了我的原始问题。

I'm wondering is there any way of counting a successful drag and drop operation, the solution below answered my original question.

推荐答案

这基本上是@ Andrew的评论的大纲 - 由于您的SSCCE，容易实现： - ）

This is basically an outline of @Andrew's comment - easily possible due to your SSCCE :-)

子类TransferHandler，重写canImport以检查源标签是否在imageSelect面板上，如果是，则拒绝。

Subclass TransferHandler, override canImport to check if the source label is on the imageSelect panel and reject if so.

    // custom transferHandler which decides about imports based on source
    TransferHandler handler = new TransferHandler("icon") {

        @Override
        public boolean canImport(TransferSupport support) {
            return super.canImport(support) 
                    && support.getComponent().getParent() != imageSelectPanel;
        }

    };
    // use the handler on all labels (handlers can be shared, btw)
    // for each label on imageSelectPanel
    imageSelectLabel.setTransferHandler(handler)
    // for each label on the target panel (aka storyPanel) 
    storyLabel.setTransferHandler(handler)

这篇关于Java的。拖曳将ImageIcon从面板1上的JLabel拖放到面板上的JLabel 2.添加计数器功能的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！