以下是我删除节点的代码: public void jTree1_valueChanged(TreeSelectionEvent e) {
DefaultMutableTreeNode selNode = (DefaultMutableTreeNode)jTree1.getLastSelectedPathComponent();
TreeNode selRoot = selNode.getParent();
selNode.removeFromParent();
}我尝试了validate(),inValidate()都不行,有人说用updateUI(),但是这个方法显然不对,这个方法由UIManager调用,用于发出L&F已经更改的通知,并且如果手动调用将发生异常,以下是异常信息:Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.plaf.basic.BasicTreeUI.isToggleEvent(BasicTreeUI.java:2192)
at javax.swing.plaf.basic.BasicTreeUI.selectPathForEvent(BasicTreeUI.java:2257)
at javax.swing.plaf.basic.BasicTreeUI$Handler.handleSelection(BasicTreeUI.java:3442)
at javax.swing.plaf.basic.BasicTreeUI$Handler.mousePressed(BasicTreeUI.java:3403)
at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:222)
at java.awt.Component.processMouseEvent(Component.java:5485)1 at javax.swing.JComponent.processMouseEvent(JComponent.java:3093)
at java.awt.Component.processEvent(Component.java:5253)
at java.awt.Container.processEvent(Container.java:1966)
at java.awt.Component.dispatchEventImpl(Component.java:3955)
at java.awt.Container.dispatchEventImpl(Container.java:2024)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3889)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
at java.awt.Container.dispatchEventImpl(Container.java:2010)
at java.awt.Window.dispatchEventImpl(Window.java:1774)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
DefaultMutableTreeNode selNode = (DefaultMutableTreeNode)jTree1.getLastSelectedPathComponent();
TreeNode selRoot = selNode.getParent();
selNode.removeFromParent();
}我尝试了validate(),inValidate()都不行,有人说用updateUI(),但是这个方法显然不对,这个方法由UIManager调用,用于发出L&F已经更改的通知,并且如果手动调用将发生异常,以下是异常信息:Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.plaf.basic.BasicTreeUI.isToggleEvent(BasicTreeUI.java:2192)
at javax.swing.plaf.basic.BasicTreeUI.selectPathForEvent(BasicTreeUI.java:2257)
at javax.swing.plaf.basic.BasicTreeUI$Handler.handleSelection(BasicTreeUI.java:3442)
at javax.swing.plaf.basic.BasicTreeUI$Handler.mousePressed(BasicTreeUI.java:3403)
at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:222)
at java.awt.Component.processMouseEvent(Component.java:5485)1 at javax.swing.JComponent.processMouseEvent(JComponent.java:3093)
at java.awt.Component.processEvent(Component.java:5253)
at java.awt.Container.processEvent(Container.java:1966)
at java.awt.Component.dispatchEventImpl(Component.java:3955)
at java.awt.Container.dispatchEventImpl(Container.java:2024)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3889)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
at java.awt.Container.dispatchEventImpl(Container.java:2010)
at java.awt.Window.dispatchEventImpl(Window.java:1774)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
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这句是没有用的,我忘了删掉。
DefaultMutableTreeNode selNode =(DefaultMutableTreeNode)jTree1.getLastSelectedPathComponent();
treeModel.removeNodeFromParent(selNode);你试试这样可以不?
at swingteaching.TTFrame.jTree1_valueChanged(TTFrame.java:64)
at swingteaching.TTFrame_jTree1_treeSelectionAdapter.valueChanged(TTFrame.java:77)
at javax.swing.JTree.fireValueChanged(JTree.java:2399)
at javax.swing.JTree$TreeSelectionRedirector.valueChanged(JTree.java:2770)
at javax.swing.tree.DefaultTreeSelectionModel.fireValueChanged(DefaultTreeSelectionModel.java:629)
at javax.swing.tree.DefaultTreeSelectionModel.notifyPathChange(DefaultTreeSelectionModel.java:1078)bananas at javax.swing.tree.DefaultTreeSelectionModel.removeSelectionPaths(DefaultTreeSelectionModel.java:497)
at javax.swing.JTree.removeDescendantSelectedPaths(JTree.java:3095)
at javax.swing.JTree.removeDescendantSelectedPaths(JTree.java:3145)
at javax.swing.JTree$TreeModelHandler.treeNodesRemoved(JTree.java:3229)
at javax.swing.tree.DefaultTreeModel.fireTreeNodesRemoved(DefaultTreeModel.java:528)
at javax.swing.tree.DefaultTreeModel.nodesWereRemoved(DefaultTreeModel.java:308)
at javax.swing.tree.DefaultTreeModel.removeNodeFromParent(DefaultTreeModel.java:244)
at swingteaching.TTFrame.jTree1_valueChanged(TTFrame.java:65)
at swingteaching.TTFrame_jTree1_treeSelectionAdapter.valueChanged(TTFrame.java:77)
at javax.swing.JTree.fireValueChanged(JTree.java:2399)
at javax.swing.JTree$TreeSelectionRedirector.valueChanged(JTree.java:2770)
at javax.swing.tree.DefaultTreeSelectionModel.fireValueChanged(DefaultTreeSelectionModel.java:629)
at javax.swing.tree.DefaultTreeSelectionModel.notifyPathChange(DefaultTreeSelectionModel.java:1078)
at javax.swing.tree.DefaultTreeSelectionModel.setSelectionPaths(DefaultTreeSelectionModel.java:287)
at javax.swing.tree.DefaultTreeSelectionModel.setSelectionPath(DefaultTreeSelectionModel.java:170)
at javax.swing.JTree.setSelectionPath(JTree.java:1174)
at javax.swing.plaf.basic.BasicTreeUI.selectPathForEvent(BasicTreeUI.java:2256)
at javax.swing.plaf.basic.BasicTreeUI$Handler.handleSelection(BasicTreeUI.java:3442)
at javax.swing.plaf.basic.BasicTreeUI$Handler.mousePressed(BasicTreeUI.java:3403)
at java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:222)
at java.awt.Component.processMouseEvent(Component.java:5485)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3093)
at java.awt.Component.processEvent(Component.java:5253)
at java.awt.Container.processEvent(Container.java:1966)
at java.awt.Component.dispatchEventImpl(Component.java:3955)
at java.awt.Container.dispatchEventImpl(Container.java:2024)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3889)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
at java.awt.Container.dispatchEventImpl(Container.java:2010)
at java.awt.Window.dispatchEventImpl(Window.java:1774)
at java.awt.Component.dispatchEvent(Component.java:3803)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)