objective-c – 可可：如何使多行NSTextField？

以下是技术说明中的委托消息示例：

- (BOOL)control:(NSControl*)control textView:(NSTextView*)textView doCommandBySelector:(SEL)commandSelector
{
    BOOL result = NO;

    if (commandSelector == @selector(insertNewline:))
    {
        // new line action:
        // always insert a line-break character and don’t cause the receiver to end editing
        [textView insertNewlineIgnoringFieldEditor:self];
        result = YES;
    }
    else if (commandSelector == @selector(insertTab:))
    {
        // tab action:
        // always insert a tab character and don’t cause the receiver to end editing
        [textView insertTabIgnoringFieldEditor:self];
        result = YES;
    }

    return result;
}