JavaFX TableView性能问题 [英] JavaFX TableView performance issue

问题描述

我正在使用javafx表视图控件来显示我的表数据。现在数据非常庞大，当我在控件中显示完整数据时，它会崩溃。有没有办法这样做或者我必须缓存数据，以便我可以以块的形式显示它。我应该使用JTable吗？

I am using javafx table view control to display my table data. Now the data is quite huge and when I show the full data in the control it crashes. Is there any way to do so or will I have to cache the data so that I can display it in chunks. Should I use JTable instead ?

推荐答案

我使用CellFactory类对tableview进行了延迟加载...我会尝试解释一下，任何英语都比我好的人都可以自由编辑并使其更容易理解！

I made a lazy-load on tableview using the CellFactory class... I´ll try to explain, anyone with better english than mine fell free to edit and make it more understandable!

首先我在Bean中使用强制属性来检查该bean是否已经存在已加载或未加载。这样我就不需要专门为它创建一个属性。

First I use a mandatory property in a Bean to check if that bean has already been loaded or not. This way I don't need to create an attribute specifically for that.

其次，我加载到TableView我的Bean集合只是加载了'id'属性，是什么让我的表格全部显示为空白。

Second, I loaded into TableView my Bean collection just with the 'id' property loaded, what makes my table display all in blank.

最后，我创建一个CellFactory，如下所示，检查对象是否已加载，如果现在不加载。

At last, I create a CellFactory, like this one below, to check if object has loaded or not, and if not do it now.

namecolumn.setCellFactory(new Callback<TableColumn<PersonBean, String>, TableCell<PersonBean, String>>() {
@Override
  public TableCell<PersonBean, String> call(TableColumn<PersonBean, String> param) {
    TableCell<PersonBean, String> newtablecell = new TableCell<PersonBean, String>() {
      @Override
      protected void updateItem(String item, boolean empty) {
        // Since I got some strange errors when method getIndex() return greatter value than my collection size, I need to validate before getting the object
        if (getIndex() < getItems().size()) {
          //Retrieve the collection object
          PersonBean personbean = getItems().get(getIndex());
          // Name is mandatory, so if it is null my bean was not loaded yet
          if (personbean.getName() == null) {
            // Call other centralized method to make load, details explained later
            loadPersonBean(personbean);
          }
          // Now I put the value on TableCell. Remember "item" still empty so we need to use Bean
          setText(personbean.getName());
          setAlignment(Pos.CENTER);
        }
      }
    };
    return newtablecell;
  }
});

在方法loadPersonBean中，我传递TableView Collection中包含的对象并从DataBase加载它。比我将所有需要的数据复制到从表中收到的bean。我没有尝试在TableView中交换对象，但我相信它可能会导致并发异常。

In the method loadPersonBean I pass the object contained in TableView Collection and load it from DataBase. Than I COPY all the needed data to the bean received from the table. I didn't try to swap the object in TableView, but I believe it may result a Concurrent Exception.

其他观察：在我的所有测试中，TableView始终遵循列顺序调用我的CellFactory，但是如果用户交换列顺序，我没有测试它是否仍然遵守订单。所以我更喜欢在所有列中添加一个带有LazyLoadCheck代码部分的CellFactory。

Other observation: In all my tests TableView always respects the column order to call my CellFactory, but I did not test if it still respects the order if user swap the column order. So I prefer to add a CellFactory with the "LazyLoadCheck" part of code to all columns.

希望我能够清楚地帮助我！如果仍有问题，请发表评论，我会尝试做出更好的解释。

Hope I made my self clear enough to help! If any questions remains, comment and I'll try to do a better explanation.

这篇关于JavaFX TableView性能问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！