android. 使用recyclerView 做头像挂件 全代码

好的，下面是使用 RecyclerView 实现头像挂件的示例代码：

首先，创建一个 AvatarModel 类，用于表示每个头像挂件的数据：

public class AvatarModel {
    private String imageUrl;

    public AvatarModel(String imageUrl) {
        this.imageUrl = imageUrl;
    }

    public String getImageUrl() {
        return imageUrl;
    }
}

然后，创建一个 RecyclerView.Adapter 的子类 AvatarAdapter，用于管理头像挂件的显示：

public class AvatarAdapter extends RecyclerView.Adapter<AvatarAdapter.AvatarViewHolder> {
    private List<AvatarModel> avatarList;

    public AvatarAdapter(List<AvatarModel> avatarList) {
        this.avatarList = avatarList;
    }

    @NonNull
    @Override
    public AvatarViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_avatar, parent, false);
        return new AvatarViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull AvatarViewHolder holder, int position) {
        AvatarModel avatar = avatarList.get(position);
        Glide.with(holder.itemView.getContext()).load(avatar.getImageUrl()).into(holder.avatarImageView);
    }

    @Override
    public int getItemCount() {
        return avatarList.size();
    }

    public static class AvatarViewHolder extends RecyclerView.ViewHolder {
        public ImageView avatarImageView;

        public AvatarViewHolder(@NonNull View itemView) {
            super(itemView);
            avatarImageView = itemView.findViewById(R.id.avatarImageView);
        }
    }
}

其中，AvatarViewHolder 用于管理头像挂件的视图，item_avatar.xml 是头像挂件的布局文件，如下所示：

<ImageView
    android:id="@+id/avatarImageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="8dp"
    android:src="@drawable/avatar_placeholder" />

最后，在 Activity 或 Fragment 中，创建 RecyclerView 并设置 AvatarAdapter，如下所示：

public class AvatarActivity extends AppCompatActivity {
    private RecyclerView recyclerView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_avatar);

        recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false));

        List<AvatarModel> avatarList = new ArrayList<>();
        avatarList.add(new AvatarModel("https://example.com/avatar1.png"));
        avatarList.add(new AvatarModel("https://example.com/avatar2.png"));
        avatarList.add(new AvatarModel("https://example.com/avatar3.png"));

        AvatarAdapter adapter = new AvatarAdapter(avatarList);
        recyclerView.setAdapter(adapter);
    }
}

其中，activity_avatar.xml 包含一个 RecyclerView，如下所示：

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/recyclerView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

这样，就可以通过 RecyclerView 显示头像挂件了。