基于视图的“源列表”NSOutlineView不显示项目的图标和标题

Question

将基于单元格的NSOutlineView更改为基于视图后，它不显示文件系统树的图标和标题。这里我的代码：

- (void)outlineView:(NSOutlineView *)outlineView willDisplayCell:(id)cell forTableColumn:(NSTableColumn *)tableColumn item:(id)item { 
    if ([[tableColumn identifier] isEqualToString:@"name"]) 
     return [(ImageAndTextCell *)cell setTextFieldImage:[item icon]]; 
} 

- (id)outlineView:(NSOutlineView *)outlineView objectValueForTableColumn:(NSTableColumn *)tableColumn byItem:(id)item { 
    return [((ConstructorFSEntity *)item) title]; 
} 

- (NSView *)outlineView:(NSOutlineView *)outlineView viewForTableColumn:(NSTableColumn *)tableColumn item:(id)item { 
    if ([item isKindOfClass:[FSEntity class]]) { 
     return [outlineView makeViewWithIdentifier:@"HeaderCell" owner:self]; 
    } else { 
     return [outlineView makeViewWithIdentifier:@"DataCell" owner:self]; 
    } 
} 

我还有一个问题。如何将枚举项目（文件系统项目的数组）放到单元格“DataCell”和“HeaderCell”中作为父文件夹（组）并声明为标题（例如，@“根文件夹”）和路径班上。因为现在以前的基于视图的方法仅在“HeaderCell”或“DataCell”中显示枚举项，并且当我尝试将某个值分配给“HeaderCell”时，应用程序崩溃。你能帮助我吗？

Answer 1

要显示的项目名称和图标，你只需要改变这个方法

- (NSView *)outlineView:(NSOutlineView *)outlineView viewForTableColumn:(NSTableColumn *)tableColumn item:(id)item

如下：

- (NSView *)outlineView:(NSOutlineView *)outlineView viewForTableColumn:(NSTableColumn *)tableColumn item:(id)item { 
    if (![item isKindOfClass:[FSEntity class]]) { 
     return [outlineView makeViewWithIdentifier:@"HeaderCell" owner:self]; 
    } else { 
     NSTableCellView *cellView = [outlineView makeViewWithIdentifier:@"DataCell" owner:self]; 
     [(ImageAndTextCell *)cellView.textField.cell setTextFieldImage:[item icon]]; 
     cellView.textField.stringValue = [((FSEntity *)item) title]; 
     return cellView; 
    } 
}