jDialog已处置，但仍在jFrame.getOwnedWindows中

Question

我有一个JFrame (EC_GUI.main)，然后创建几个JDialog，向其中添加一个JPanel，将JFrame作为所有者传递。

我现在正在检测这些JDialogs是否是通过jFrame.getOwnedWindows()打开的，因为我无法通过其中的一种打开它们

EC_GUI.main.getComponentCount() 1
javax.swing.JRootPane[,0,0,755x1005,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=]

EC_GUI.main.getRootPane().getComponentCount() 2
javax.swing.JPanel[null.glassPane,0,0,755x1005,hidden,layout=java.awt.FlowLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777217,maximumSize=,minimumSize=,preferredSize=]
javax.swing.JLayeredPane[null.layeredPane,0,0,755x1005,alignmentX=0.0,alignmentY=0.0,border=,flags=0,maximumSize=,minimumSize=,preferredSize=,optimizedDrawingPossible=true]

EC_GUI.main.getContentPane().getComponentCount() 1
ec.gui.dialogs.template.EC_BorderPanel[,0,0,755x1005,layout=java.awt.BorderLayout,alignmentX=0.0,alignmentY=0.0,border=javax.swing.border.EmptyBorder@44e6097c,flags=9,maximumSize=,minimumSize=,preferredSize=]

但是如果我查询ownedWindows，我就会得到它们

EC_GUI.main.getOwnedWindows().length 1
ec.gui.dialogs.visivilityfield.EC_VrPresetDialog$1[dialog0,385,254,502x511,invalid,hidden,layout=java.awt.BorderLayout,MODELESS,title=Virtual Reality Presets,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=javax.swing.JRootPane[,0,0,502x511,invalid,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=],rootPaneCheckingEnabled=true]

我注意到，即使我调用jDialog.dispose()，我仍然有一个引用，所以如果我打开和关闭，比方说3次，我的JDialog之一，我得到

EC_GUI.main.getOwnedWindows().length 3
ec.gui.dialogs.visivilityfield.EC_VrPresetDialog$1[dialog1,385,254,502x511,invalid,hidden,layout=java.awt.BorderLayout,MODELESS,title=Virtual Reality Presets,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=javax.swing.JRootPane[,0,0,502x511,invalid,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=],rootPaneCheckingEnabled=true]
ec.gui.dialogs.visivilityfield.EC_VrPresetDialog$1[dialog2,385,254,502x511,invalid,hidden,layout=java.awt.BorderLayout,MODELESS,title=Virtual Reality Presets,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=javax.swing.JRootPane[,0,0,502x511,invalid,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=],rootPaneCheckingEnabled=true]
ec.gui.dialogs.visivilityfield.EC_VrPresetDialog$1[dialog3,385,254,502x511,invalid,hidden,layout=java.awt.BorderLayout,MODELESS,title=Virtual Reality Presets,defaultCloseOperation=DO_NOTHING_ON_CLOSE,rootPane=javax.swing.JRootPane[,0,0,502x511,invalid,layout=javax.swing.JRootPane$RootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=16777673,maximumSize=,minimumSize=,preferredSize=],rootPaneCheckingEnabled=true]

这是正常的吗？

Answer 1

如果正确配置，dispose将释放窗口正在使用的本机资源，这不会“释放”对象，您可以通过调用JavaDocs重新显示窗口。

您可以检查isDisplayable (这将让您知道窗口是否仍然有对其本地对等方的引用)或更可靠的isVisible选项.

如果对话框没有其他强引用，它最终会被垃圾收集。