JavaFX：ImageView只显示一次Image(JavaFX: ImageView shows Image only once)

 在我的JavaFX应用程序中，我使用TreeView。 单个TreeItems包含一个图像。 不幸的是，图像只显示一次。 
 
 
 加载图像的代码如下所示。 每次TreeView更改时都会调用它。 Image被缓存在Map （“图标”）中。 因此，每次都会创建一个新的ImageView 。 
 
public final ImageView getImage(final String imageConstant) {
    final Image img;
    if (icons.containsKey(imageConstant)) {
        img = icons.get(imageConstant);
    }
    else {
        if (isRunFromJAR) {
           img = new Image("/path/" + imageConstant, iconSizeWidth,
                    iconSizeHeight, false, false);
        }
        else {
            img = new Image(getClass().getResourceAsStream(imageConstant), iconSizeWidth,
                    iconSizeHeight, false, false);
        }
        icons.put(imageConstant, img);
    }
    return new ImageView(img);
 
 在我的TreeCell的updateItem方法中，上面返回的ImageView存储在名为icon的字段中。 该字段在以下代码中使用，也来自updateItem ： 
 
if (icon == null) {
        setGraphic(label);
    }
    else {
        final HBox hbox = new HBox(ICON_SPACING);
        final Label iconLabel = new Label("", icon);
        hbox.getChildren().addAll(iconLabel, label);
        setGraphic(hbox);
    }
 
 但由于某种原因，gif中出现的问题出现了。 
 
 更新 
 
 实际上，ImageViews是在内部缓存的，这导致了重复数据删除。 使用多个ImageView是解决方案。 

In my JavaFX application I use a TreeView. The single TreeItems contain an image. Unfortunately, the image is shown only once. 
 
 
The code for loading the image looks like the following. It is called every time the TreeView changes. The Images are cached in a Map ("icons"). Thus, a new ImageView is created every time.
 
public final ImageView getImage(final String imageConstant) {
    final Image img;
    if (icons.containsKey(imageConstant)) {
        img = icons.get(imageConstant);
    }
    else {
        if (isRunFromJAR) {
           img = new Image("/path/" + imageConstant, iconSizeWidth,
                    iconSizeHeight, false, false);
        }
        else {
            img = new Image(getClass().getResourceAsStream(imageConstant), iconSizeWidth,
                    iconSizeHeight, false, false);
        }
        icons.put(imageConstant, img);
    }
    return new ImageView(img);
 
In the updateItem method of my TreeCells, the ImageView returned above is stored into a field called icon. The field is used in the following code, also from updateItem:
 
if (icon == null) {
        setGraphic(label);
    }
    else {
        final HBox hbox = new HBox(ICON_SPACING);
        final Label iconLabel = new Label("", icon);
        hbox.getChildren().addAll(iconLabel, label);
        setGraphic(hbox);
    }
 
But for some reason, the problem shown in the gif occurs. 
 
Update
 
Actually, the ImageViews were cached internally, which led to de-duplication. Using multiple ImageViews is the solution.

原文：https://stackoverflow.com/questions/36280987