Question

app中有两个Arraylist。第一个Arraylist is ArrayList<Thumbnail> videoList = new ArrayList<>()和第二个ArrayList是ArrayList<Giphy> giphylist = new ArrayList()。

giasterist arraylist项目在videoList中更新。如何更新第一个ArrayList videoList项目值中的第二个ArrayList GiphyList项目值？

我尝试了addAll（）函数。可以使用此函数覆盖Arraylist吗？就像这样：videoList = new ArrayList<Thumbnail>(giphyList); 这也给错误：无法解析构造函数ArrayList（java.util.List）

Thumbnail.java

public class Thumbnail {


    private String gif,videoUrl;
    private int id, thumbUp, thumbDown;

    public Thumbnail (int id,String gif,String videoUrl,int thumbUp,int thumbDown){


        this.gif = gif;
        this.videoUrl = videoUrl;
        this.thumbUp =thumbUp;
        this.thumbDown = thumbDown;
        this.id = id;
    }

    public String getGif() {
        return gif;
    }

    public void setGif(String gif) {
        this.gif = gif;
    }

    public String getVideoUrl() {
        return videoUrl;
    }

    public void setVideoUrl(String videoUrl) {
        this.videoUrl = videoUrl;
    }

    public int getId() {
        return id;
    }

    public int getThumbUp() {
        return thumbUp;
    }

    public int getThumbDown() {
        return thumbDown;
    }

    public void setId(int id) {
        this.id = id;
    }

    public void setThumbUp(int thumbUp) {
        this.thumbUp = thumbUp;
    }

    public void setThumbDown(int thumbDown) {
        this.thumbDown = thumbDown;
    }
}

Giphy.java

@Entity
public class Giphy {

    @Id(assignable = true)
    private long id;
    private String url;
    private int thumbUp;
    private int thumbDown;
    private String gif;


//    public Giphy(){

  //  }

    public Giphy(long id,String gif,String url,int thumbUp,int thumbDown){

        this.id = id;
        this.url = url;
        this.thumbUp = thumbUp;
        this.thumbDown = thumbDown;
        this.gif = gif;
    }

    public long getId() {
        return id;
    }

    public String getUrl() {
        return url;
    }

    public int getThumbUp() {
        return thumbUp;
    }

    public int getThumbDown() {
        return thumbDown;
    }

    public void setId(long id) {
        this.id = id;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public void setThumbUp(int thumbUp) {
        this.thumbUp = thumbUp;
    }

    public void setThumbDown(int thumbDown) {
        this.thumbDown = thumbDown;
    }

    public String getGif() {
        return gif;
    }

    public void setGif(String gif) {
        this.gif = gif;
    }
}

Answer 1

Thumbnail和Giphy是不兼容的类型。创建映射功能/构造函数以从一种类型切换到另一种类型，或者将它们组合成一种类型。

例如：

class Giphy {
    //...
    Thumbnail toThumbnail()  {
        return new Thumbnail(id,gif,videoUrl,thumbUp,thumbDown);
    }
}

而不是videoList = new ArrayList<>(giphyList);

final List<Thumbnail> thumbnails = giphyList.stream().map(Giphy::toThumbnail).collect(toList());

Answer 2

最好的解决方案是对象。

ArrayList<Object> allItems = new ArrayList<>();

现在将缩略图Arraylist添加到allItems。

allItems.add(thumbnailList);

最后结合技师。

allItems.addAll(giphylist);

从Object ArrayList获取价值

Thumbnail thumbnail =(Thumbnail)allItems.get(position index);
System.out.println(thumbnail.videoUrl);

如何在第一个Arraylist中更新第二个Arraylist？

2 个答案: