Question

我在Pebble手表中运行了一些C代码。它正在接收一些数据，每次都作为键值对。它接收5个数据，每个数据都有正确的密钥和值，如下所示：

Key: 5 Value: '0'
Key: 6 Value: '10'
Key: 7 Value: '20'
Key: 8 Value: '30'
Key: 9 Value: '40'

pebble一次接收其中一对，每次调用以下函数（上一行：SimpleMenuItem chats[5];）

void in_received_handler(DictionaryIterator *received, void *context) {
    dataReceived = dict_read_first(received);
    APP_LOG(APP_LOG_LEVEL_DEBUG, "read first");
    while (dataReceived != NULL){

        APP_LOG(APP_LOG_LEVEL_DEBUG, dataReceived->value->cstring);
        char keystr[10];
        snprintf(keystr, 10, "Key: %d", (int)dataReceived->key);
        APP_LOG(APP_LOG_LEVEL_DEBUG, keystr);

        snprintf(keystr, 10, "Index: %d", (int)dataReceived->key -5);
        APP_LOG(APP_LOG_LEVEL_DEBUG, keystr);
        chats[dataReceived->key - 5] = (SimpleMenuItem){
                    // You should give each menu item a title and callback
                    .title = dataReceived->value->cstring,
                    .callback = selected_chat,
                };

        dataReceived = dict_read_next(received);
        APP_LOG(APP_LOG_LEVEL_DEBUG, "read again");
    }

    layer_mark_dirty((Layer *)instant_chats);
}

然后将以下内容输出到卵石日志（这是我认为是正确的）：

[DEBUG] sr.c:195: read first
[DEBUG] sr.c:197: 0
[DEBUG] sr.c:200: Key: 5
[DEBUG] sr.c:219: Index: 0
[DEBUG] sr.c:243: read again
[DEBUG] sr.c:195: read first
[DEBUG] sr.c:197: 10
[DEBUG] sr.c:200: Key: 6
[DEBUG] sr.c:219: Index: 1
[DEBUG] sr.c:243: read again
[DEBUG] sr.c:195: read first
[DEBUG] sr.c:197: 20
[DEBUG] sr.c:200: Key: 7
[DEBUG] sr.c:219: Index: 2
[DEBUG] sr.c:243: read again
[DEBUG] sr.c:195: read first
[DEBUG] sr.c:197: 30
[DEBUG] sr.c:200: Key: 8
[DEBUG] sr.c:219: Index: 3
[DEBUG] sr.c:243: read again
[DEBUG] sr.c:195: read first
[DEBUG] sr.c:197: 40
[DEBUG] sr.c:200: Key: 9
[DEBUG] sr.c:219: Index: 4
[DEBUG] sr.c:243: read again

所以，虽然一切看起来都是正确的（对我而言），但却出现了意想不到的行为。而不是让chats成为每个元素具有不同值的SimpleMenuItem数组，相同的数据（即最新的）会覆盖所有值，即使它（可能）应该只写在指定的元素上。因此，在发送的5个数据的末尾，整个chats数组最终被SimpleMenuItem值40填充。我觉得这更像是一个C问题，而不是一个特殊的卵石问题 - 但如果有人能解决这个问题，我会非常感激。

谢谢！

Answer 1

如评论中所述，您需要复制字符串，否则它们都指向内存中的相同地址并被覆盖。

请参阅我对相关问题的回复：Converting char array to string [and Pebble]。

数组的所有元素都被覆盖而不是只有一个？

1 个答案: