你如何NSWindow从工具栏中显示一个,如下NSOpenPanel图所示?

从 NIB 文件的窗口属性中取消选中Visible At Launch,然后使用beginSheet:
[NSApp beginSheet:sheetWindow
modalForWindow:mainWindow
modalDelegate:self
didEndSelector:@selector(sheetDidEnd:returnCode:contextInfo:)
contextInfo:NULL];
此外,NSSavePanel提供beginSheetModalForWindow作为便捷方法:
[savePanel beginSheetModalForWindow:mainWindow completionHandler:^(NSInteger result) {
if (result != NSFileHandlingPanelOKButton) return;
// Do something
}];