Question

我的待办事项应用程序使用Room存储数据。它有两个片段：任务列表和任务详细信息（添加和编辑任务）。问题是，当我更新TaskDetailsFragment中的Task的isFavourite字段时，先前片段中的列表未更新（显示了旧的isFavourite值）。我使用了双向数据绑定来连接LiveData和视图。所有其他字段（title，description，isCompleted）在编辑后都会正确更新，只有isFavourite CheckBox出了问题。有时，当我滚动到列表的末尾（更新的项目不可见）或重新启动应用程序时，该值会正确更新。此外，当直接从列表视图更新isFavourite值时，CheckBox行为是正确的。仅从另一个Fragment更新它是有问题的。

RecyclerViewAdapter：

override fun onBindViewHolder(holder: TaskViewHolder, position: Int) {
        val task = tasks[position]

        holder.taskCheckBox.apply {
            setOnCheckedChangeListener { _, isChecked ->
                Timber.i(isChecked.toString())
                taskViewClickListener.onCheckBoxClick(position, task, isChecked)
            }
            isChecked = task.isCompleted
            setTintListByColor(task.priority.color)
        }

        holder.taskTitleTextView.apply {
            text = task.title

            setOnClickListener {
                taskViewClickListener.onTaskClick(position, task)
            }
        }

        holder.isTaskFavouriteCheckBox.apply {
            setOnCheckedChangeListener { _, isChecked ->
                taskViewClickListener.onFavouriteClick(position, task, isChecked)
            }
            isChecked = task.isFavourite
        }
    }

fun updateTasksList(newTasks: List<Task>) {    
        val callback = TaskDiffCallback(tasks, newTasks)
        val result = DiffUtil.calculateDiff(callback)

        tasks.apply {
            clear()
            addAll(newTasks)
        }

        result.dispatchUpdatesTo(this)
    }

TaskDao：

@Query("SELECT * FROM tasks WHERE is_completed = 0 ORDER BY creation_date DESC")
fun getAllOrderedByCreationDate(): Flow<List<Task>>

@Update
suspend fun update(task: Task)

任务存储库：

fun getAll(): Flow<List<Task>> {
    return taskDao.getAllOrderedByCreationDate()
}

TaskViewModel：

var tasks: LiveData<List<Task>> = taskRepository.getAll().asLiveData()

任务片段：

viewModel.tasks.observe(this) {
    recyclerViewAdapter.updateTasksList(it)
}

TaskDetailsViewModel：

fun saveTask(inEditMode: Boolean) {
    val success = updateTaskDetails()

    if (success) {
        if (inEditMode)
            updateTask(task)
        else
            insertTask(task)

        scheduleReminder()
        _taskSaved.call()
    }
}

private fun updateTaskDetails(): Boolean {
    val title = taskTitle.value
    val description = taskDescription.value
    val priority = taskPriority.value
    val isFavourite = isTaskFavourite.value
    val isCompleted = isTaskCompleted.value

    if (title.isNullOrBlank()) {
        _taskError.value = "Task title cannot be empty"
        return false
    }

    if (priority == null) {
        _taskError.value = "Task priority cannot be empty"
        return false
    }

    if (isFavourite == null)
        return false

    if (isCompleted == null)
        return false

    with(task) {
        this.title = title
        this.description = description
        this.priority = priority
        this.isFavourite = isFavourite
        this.isCompleted = isCompleted
    }

    return true
}

fun updateTask(task: Task) {
    viewModelScope.launch(Dispatchers.IO) {
        taskRepository.update(task)
    }
}

会议室数据库实体未正确更新

0 个答案: