如何将相同的项目添加到适配器？

Question

我正在分析instagram关注者和关注者。我要添加适配器，该适配器可以追随用户并追随用户。

我的代码：

ArrayList<InstagramUserSummary> mutuals = new ArrayList<>(followers);
for (InstagramUserSummary i : followers) {
    for (InstagramUserSummary j : following) {
        if (i.equals(j)) {
            WHAT I HAVE TO DO HERE TO SET ADAPTER mutuals?
        }
    }    
}

Answer 1

要获取“关注者”和“关注者”之间的交集，请使用

  

Collection＃retainAll（）。

listA.retainAll(listB);
 // listA now contains only the elements which are also contained in listB.

如果要避免listA中的更改受到影响，则需要创建一个新的更改。

List<Integer> common = new ArrayList<Integer>(listA);
common.retainAll(listB); // common now contains only the elements which are contained in listA and listB.

Answer 2

ArrayList<InstagramUserSummary> mutuals = new ArrayList<>();
for (InstagramUserSummary i : followers) {
    for (InstagramUserSummary j : following) {
        if (i.equals(j)) {
            mutuals.add(i);
        }
    }    
}

// here use mutuals to create Adapter
// change this code and use your custom adapter to show users detail in list
ArrayAdapter<InstagramUserSummary> adapter = new ArrayAdapter<>(this,
          android.R.layout.simple_list_item_1, android.R.id.text1, mutuals);