Question

我正在尝试在用户选择对象所在的行后重新分配嵌套值。我基本上改造了阅读收据功能。当我使用它时，它不断抛出一个错误，说“表达式不可分配”：

[[self.conversations objectAtIndex:indexPath.row] valueForKeyPath:@"recipientRead"] = true;

并且当我使用它时，它说“在'id'类型的对象上找不到”属性'recipientRead'：

    self.conversations[indexPath.row].recipientRead = true;

如何为此键的此索引行访问此对象并为其分配新变量？

这是我的会话对象的样子：

conversations = (
"<Convo: 0x174117970, objectId: kq1H963zwX, localId: (null)> {\n    leanId = 7FvjCFbVcv;\n    messageBody = Test;\n    recipientDisplayName = Ian;\n    recipientId = SXeTdhJcRn;\n    recipientRead = 0;\n    senderDisplayName = user2;\n    senderId = rBi8XjVxx5;\n    senderRead = 1;\n    timeStamp = \"2015-08-18 14:31:48\";\n}",
"<Convo: 0x17410e340, objectId: 4VAkXEJK4i, localId: (null)> {\n    leanId = maLdMRcsRS;\n    messageBody = \"Test 555\";\n    recipientDisplayName = Ian;\n    recipientId = SXeTdhJcRn;\n    senderDisplayName = user2;\n    senderId = rBi8XjVxx5;\n    timeStamp = \"2015-08-16 15:38:19\";\n}",
"<Convo: 0x17010f9c0, objectId: Sbct8LnaMg, localId: (null)> {\n    leanId = tOYG4Einld;\n    messageBody = Test;\n    recipientDisplayName = Ian;\n    recipientId = SXeTdhJcRn;\n    senderDisplayName = user2;\n    senderId = rBi8XjVxx5;\n    timeStamp = \"2015-08-16 15:32:45\";\n}",

Answer 1

这是因为.dot符号需要强类型

ClassName *conversation = self.conversations[indexPath.row];
conversation.recipientRead = YES;

只需使用您自己的类名，因为它未在您的示例中指定;）

重新分配嵌套键值

1 个答案: