android– 在RecyclerView适配器中使用自定义视图？

概述我有一个基本的自定义视图,如下所示：publicclassCustomViewextendsRelativeLayout{privateUseruser;privateImageViewprofilePicture;publicCustomView(Contextcontext){super(context);init();}publicCustomView(Co

我有一个基本的自定义视图,如下所示：

public class CustomVIEw extends relativeLayout {    private User user;    private ImageVIEw profilePicture;    public CustomVIEw(Context context) {        super(context);        init();    }    public CustomVIEw(Context context, AttributeSet attrs) {        super(context, attrs);        init();    }    private voID init() {        inflate(getContext(), R.layout.custom_layout, this);        profilePicture = (ImageVIEw) findVIEwByID(R.ID.profilePicture);        // ACCESS USER MODEL HERE        // e.g. user.getUsername()    }}

如您所见,我想在VIEw中访问用户数据(即：user.getUsername()).

我还需要能够在RecyclerVIEw适配器中使用自定义视图.

这是我的适配器目前的​​样子：

public class MyAdapter extends RecyclerVIEw.Adapter<MyAdapter.VIEwHolder> {    private Context context;    private List<User> userData;    public MyAdapter(Context context, List<User> userData) {        this.context = context;        this.userData = userData;    }    public class VIEwHolder extends RecyclerVIEw.VIEwHolder {        public VIEwHolder(VIEw v) {            super(v);        }    }    @OverrIDe    public VIEwHolder onCreateVIEwHolder(VIEwGroup parent, int vIEwType) {        LayoutInflater inflater = LayoutInflater.from(context);        // HOW TO INFLATE THE CUSTOM VIEW?        // VIEwHolder vIEwHolder = new VIEwHolder(customVIEw);        return vIEwHolder;    }    @OverrIDe    public voID onBindVIEwHolder(final VIEwHolder holder, int position) {        // ANYTHING HERE?    }    @OverrIDe    public int getItemCount() {        return userData.size();    }}

如何在适配器中充气自定义视图？
另外,我应该在onBindVIEwHolder()中添加任何内容吗？

注意：我必须使用自定义视图,因为我在不同的适配器下使用此视图(即：不仅仅是这个RecyclerVIEw适配器).

解决方法:

假设一个CustomVIEw类看起来像这样：

public class CustomVIEw extends relativeLayout {    private User user;    private ImageVIEw profilePicture;    // overrIDe all constructors to ensure custom logic runs in all cases    public CustomVIEw(Context context) {        this(context, null);    }    public CustomVIEw(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public CustomVIEw(Context context, AttributeSet attrs, int defStyleAttr) {        this(context, attrs, defStyleAttr, 0);    }    public CustomVIEw(            Context context,            AttributeSet attrs,            int defStyleAttr,            int defStyleRes    ) {        super(context, attrs, defStyleAttr, defStyleRes);        // put all custom logic in this constructor, which always runs        inflate(getContext(), R.layout.custom_layout, this);        profilePicture = (ImageVIEw) findVIEwByID(R.ID.profilePicture);    }    public voID setUser(User newUser) {        user = newUser;        // ACCESS USER MODEL HERE        // e.g. user.getUsername()    }}

您的RecyclerVIEw.Adapter和RecyclerVIEw.VIEwHolder看起来像这样：

public class MyAdapter extends RecyclerVIEw.Adapter<MyAdapter.VIEwHolder> {    // no Context reference needed—can get it from a VIEwGroup parameter    private List<User> userData;    public MyAdapter(List<User> userData) {        // make own copy of the List so it can't be edited externally        this.userData = new ArrayList<User>(userData);    }    @OverrIDe    public int getItemCount() {        return userData.size();    }    @OverrIDe    public VIEwHolder onCreateVIEwHolder(VIEwGroup parent, int vIEwType) {        // no need for a LayoutInflater instance—        // the custom vIEw inflates itself        CustomVIEw itemVIEw = new CustomVIEw(parent.getContext());        // manually set the CustomVIEw's size        itemVIEw.setLayoutParams(new VIEwGroup.LayoutParams(                VIEwGroup.LayoutParams.MATCH_PARENT,                VIEwGroup.LayoutParams.WRAP_CONTENT        ));        return new VIEwHolder(itemVIEw);    }    @OverrIDe    public voID onBindVIEwHolder(final VIEwHolder holder, int position) {        holder.getCustomVIEw().setUser(userData.get(position));    }    public class VIEwHolder extends RecyclerVIEw.VIEwHolder {        private CustomVIEw customVIEw;        public VIEwHolder(VIEw v) {            super(v);            customVIEw = (CustomVIEw) v;        }        public CustomVIEw getCustomVIEw() {            return customVIEw;        }    }}

> CustomVIEw管理自己的设置,它在自己的构造函数中发生,在这种情况下使用XML文件的膨胀. (或者,它可以以编程方式设置其子视图.)
>因此,RecyclerVIEw.Adapter不需要执行任何通胀 – 它只是创建一个新的CustomVIEw实例,并让CustomVIEw担心自己的设置.
>在调用setUser方法之前,CustomVIEw无法获取User实例,因此在构造函数中不能进行用户访问.在任何情况下,在一个CustomVIEw生命周期内,RecyclerVIEw可以要求它在不同时间显示许多不同用户的信息. CustomVIEw需要能够执行此 *** 作.因此,引入了setUser方法.
>因为CustomVIEw是通过代码而不是XML实例化的,所以无法在XML中定义大小的属性.因此,在定时之后以编程方式完成大小调整.
> onBindVIEwHolder只需在CustomVIEw上调用setUser即可将CustomVIEw与正确的User实例链接起来.
> VIEwHolder类现在只是RecyclerVIEw项和CustomVIEw之间的链接.

在RecyclerVIEws中使用来自另一个类的预构建的自定义视图(即不在RecyclerVIEw.Adapter中膨胀XML)似乎从未被讨论过.我认为这是一个很好的想法,即使自定义视图专门用于RecyclerVIEw,因为它是promotes separation of concerns和adherence to the Single Responsibility Principle.

总结

以上是内存溢出为你收集整理的android – 在RecyclerView适配器中使用自定义视图？全部内容，希望文章能够帮你解决android – 在RecyclerView适配器中使用自定义视图？所遇到的程序开发问题。

如果觉得内存溢出网站内容还不错，欢迎将内存溢出网站推荐给程序员好友。