Question

帮助程序类

public class HomeScreenChatsHelper implements Comparable  {

private String ID;
private String Name;
private String Image;
private String From;
private String Seen;
private String LastMessage;
private String LastMessageTime;

public HomeScreenChatsHelper(){
}


public HomeScreenChatsHelper(String id, String name, String image, String from, String seen, String lastmessage, String lastMessageTime) {
    this.ID=id;
    this.Name = name;
    this.Image = image;
    this.From = from;
    this.Seen = seen;
    this.LastMessage = lastmessage;
    this.LastMessageTime = lastMessageTime;
}

public String getID() {
    return ID;
}

public void setID(String id) {
    ID = id;
}

public String getName() {
    return Name;
}

public void setName(String name) {
    Name = name;
}

public String getImage() {
    return Image;
}

public void setImage(String image) {
    Image = image;
}

public String getMessage() {
    return LastMessage;
}

public void setMessage(String message) {
    LastMessage = message;
}

public String getTime() {
    return LastMessageTime;
}

public void setTime(String time) {
    LastMessageTime = time;
}

public String getFrom() {
    return From;
}

public void setFrom(String from) {
    From = from;
}

public String getSeen() {
    return Seen;
}

public void setSeen(String seen) {
    Seen = seen;
}

@RequiresApi(api = Build.VERSION_CODES.KITKAT)
@Override
public int compareTo(Object comparestu) {
    long compareage= Long.parseLong(((HomeScreenChatsHelper)comparestu).getTime());

    long a = Long.parseLong(LastMessageTime);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {

    }
    return Long.compare(a,compareage);
}

@Override
public boolean equals(Object o) {
    if (this == o) return true;
    if (!(o instanceof HomeScreenChatsHelper)) return false;

    HomeScreenChatsHelper that = (HomeScreenChatsHelper) o;

    return getID().equals(that.getID());
}

@Override
public int hashCode() {
    return getID().hashCode();
}

活动

          for(HomeScreenChatsHelper str : mChats) {
                if (str.getID().equals(ID)) {
                    mChats.remove(ID);
                    break;
                }
            }

关于如何做到这一点，有很多教程，而过去一周我一直在寻找解决方案，但我仍然没有。无论如何，仅指定ID即可删除整个对象吗？我将没有其他所有字段的值，因此我只想通过其ID删除特定对象。我也不能使用clear选项，因为我需要其他数据。那有人可以帮我吗？

使用当前代码没有任何反应。没有错误，但不起作用

Answer 1

通过使用java-8，您可以过滤列表，结果将是List<HomeScreenChatsHelper>与HomeScreenChatsHelper相同的id

List<HomeScreenChatsHelper> mChats = new ArrayList<>();

//filter
List<HomeScreenChatsHelper> result = mChats.stream()
                                     .filter(str->!str.getId().equals(Id)).
                                      .collect(Collectors.toList());

或使用Iterator

// Iterator.remove() 
    Iterator itr = mChats.iterator(); 
    while (itr.hasNext()) 
    { 
        HomeScreenChatsHelper x = itr.next(); 
        if (x.getId().equals(Id))  }
            itr.remove(); 
           }
    }

Answer 2

您的问题还不清楚。 mChats是包含HomeScreenChatsHelper对象的列表吗？我想是这样。如果是这种情况，则可以将foreach循环更改为普通循环

//Assuming mChats is List e.g ArrayList
for (int i = 0; mChats.size(); i++){
            if (mChats.get(i).getID().equals(ID)) {
                mChats.remove(i);
                break;
            }
        }

Answer 3

Java 8或更高版本中最简单的方法是使用Collection#removeIf：

mChats.removeIf(str -> str.getID().equals(ID));

顺便说一句，Java中的约定是字段以小写字母开头。

从值中删除完整对象

3 个答案: