带分隔符的 RecyclerView 导航抽屉
RecyclerView Navigation Drawer with separators
我开发了一个 Material 基于设计的导航抽屉，其中包含一个 Header 视图，遵循本教程：How To Make Material Design Navigation Drawer With Header View。
我试图在其下方添加一个带有类别名称的分隔符，但与我的分隔符相对应的数据集位置似乎有问题。这意味着分隔符加载正确，但不在我想要的位置。
基本上我尝试做的是将 "DrawerItem" object 的 ArrayList 传递到 "MyAdapter" class 扩展 RecyclerView。 arraylist 包含所有内容：
-header的参数
-项目名称和图标
- 和分隔符，也将自己设计为 DrawerItem object 但只有一个字符串作为标题（在我的例子中 "Others"）。
这是我的代码：
DrawerItem:
package madapps.materialdesignappbar;
public class DrawerItem {
String ItemName;
int imgResID;
String title;
String name ;
String email ;
int profile ;
public DrawerItem(String Name, String Email, int profileResID){
name = Name;
email = Email;
profile = profileResID;
}
public DrawerItem(String itemName, int imgResID) {
ItemName = itemName;
this.imgResID = imgResID;
}
//separator case
public DrawerItem(String title) {
this(null, 0);
this.title = title;
this.ItemName = "separator";
}
public String getTitle(){
return title;
}
public void setTitle(String title){
this.title = title;
}
public String getItemName() {
return ItemName;
}
public int getImgResID() {
return imgResID;
}
public void setItemName(String itemName) {
this.ItemName = itemName;
}
public void setImgResID(int imgResID) {
this.imgResID = imgResID;
}
public void setName(String Name){
this.name = Name;
}
public void setEmail(String Email){
this.email = Email;
}
public void setProfile(int Profile){
this.profile = Profile;
}
public String getName(){
return name;
}
public String getEmail(){
return email;
}
public int getProfile(){
return profile;
}
}
MyAdapter
package madapps.materialdesignappbar;
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private static final int TYPE_HEADER = 0; // Declaring Variable to Understand which View is being worked on
// IF the view under inflation and population is header or Item
private static final int TYPE_ITEM = 1;
private static final int TYPE_SEPARATOR = 2;
private ArrayList<DrawerItem> data;
MyAdapter(ArrayList<DrawerItem> Data){
// MyAdapter Constructor with titles and icons parameter
// titles, icons, name, email, profile pic are passed from the main activity as we have seen earlier
data = Data;
}
// Creating a ViewHolder which extends the RecyclerView View Holder
// ViewHolder are used to to store the inflated views in order to recycle them
public static class ViewHolder extends RecyclerView.ViewHolder {
int Holderid;
LinearLayout itemLayout;
TextView textView;
ImageView imageView;
ImageView profile;
TextView Name;
TextView email;
TextView drawerTitle;
LinearLayout separatorLayout;
// Creating ViewHolder Constructor with View and viewType As a parameter
public ViewHolder(View itemView, int ViewType) {
super(itemView);
// Here we set the appropriate view in accordance with the
// the view type as passed when the holder object is created
if (ViewType == TYPE_HEADER){
Name = (TextView) itemView.findViewById(R.id.name); // Creating Text View object from header.xml for name
email = (TextView) itemView.findViewById(R.id.email); // Creating Text View object from header.xml for email
profile = (ImageView) itemView.findViewById(R.id.circleView); // Creating Image view object from header.xml for profile pic
Holderid = 0; // Setting holder id = 0 as the object being populated are of type header view
}
if(ViewType == TYPE_ITEM) {
textView = (TextView) itemView.findViewById(R.id.rowText); // Creating TextView object with the id of textView from item_row.xml
imageView = (ImageView) itemView.findViewById(R.id.rowIcon); // Creating ImageView object with the id of ImageView from item_row.xml
Holderid = 1; // setting holder id as 1 as the object being populated are of type item row
}
if(ViewType == TYPE_SEPARATOR){
drawerTitle = (TextView) itemView.findViewById(R.id.drawerTitle);
Holderid = 2;
}
}
}
//Below first we Override the method onCreateViewHolder which is called when the ViewHolder is
//Created, In this method we inflate the item_row.xml layout if the viewType is Type_ITEM or else we inflate header.xml
// if the viewType is TYPE_HEADER
// and pass it to the view holder
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_HEADER) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.header, parent, false); //Inflating the layout
ViewHolder vhHeader = new ViewHolder(v,viewType); //Creating ViewHolder and passing the object of type view
return vhHeader; //returning the object created
}else
if (viewType == TYPE_ITEM) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row, parent, false); //Inflating the layout
ViewHolder vhItem = new ViewHolder(v, viewType); //Creating ViewHolder and passing the object of type view
return vhItem; // Returning the created object
//inflate your layout and pass it to view holder
}
if (viewType == TYPE_SEPARATOR){
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.separator, parent, false);
ViewHolder vhSeparator = new ViewHolder(v, viewType);
return vhSeparator;
}
return null;
}
/* Next we override a method which is called when the item in a row is needed to be displayed,
@param position tells us item at which position is being constructed to be displayed
@param holder id of the holder object tell us which view type is being created 1 for item row */
@Override
public void onBindViewHolder(MyAdapter.ViewHolder holder, int position) {
if(holder.Holderid==0) {
holder.profile.setImageResource(data.get(0).getProfile()); // Similarly we set the resources for header view
holder.Name.setText(data.get(0).getName());
holder.email.setText(data.get(0).getEmail());
}
if(holder.Holderid == 1) {
// as the list view is 1going to be called after the header view so we decrement the
holder.textView.setText(data.get(position).title);
holder.imageView.setImageResource(data.get(position).imgResID);
}if (holder.Holderid==2){
holder.drawerTitle.setText(data.get(4).getItemName());
}
}
// This method returns the number of items present in the list
@Override
public int getItemCount() {
return data.size();
}
// With the following method we check what type of view is being passed
@Override
public int getItemViewType(int position) {
if (isPositionHeader(position)) {//if position == 0 return true
return TYPE_HEADER; //0
}
if(isSeparator(position)){
return TYPE_SEPARATOR;
}
return TYPE_ITEM;
}
private boolean isSeparator(int position){
return position==2;
}
private boolean isPositionHeader(int position) {
return position == 0;
}
}
如您所见，我正在用三种 objects 填充 DrawerItem 的 ArrayList，顺序为（来自 MainActivity 的代码）：
ArrayList data = new ArrayList<DrawerItem>();
data.add(new DrawerItem("Chris Benois","chris_benois@mail.com",R.mipmap.aka));
data.add( new DrawerItem("Home",R.mipmap.ic_home));
data.add( new DrawerItem("Events",R.mipmap.ic_events));
data.add( new DrawerItem("Mail", R.mipmap.ic_mail));
data.add(new DrawerItem("Others"));
data.add( new DrawerItem("Shop", R.mipmap.ic_shop));
data.add( new DrawerItem("Travel", R.mipmap.ic_travel));
问题是我的 "separator" 分隔符没有出现在我想要的位置（就在 "Shop" 项目之前），但出现在其他地方，如图所示：
如何将它移动到我想要的位置？
不知道您是否找到了解决方案，但由于您的问题帮助我了解了回收站的观点，我想我会看看我是否可以 return 帮个忙。
我发现 ViewHolder class 中最重要的方法是 getItemViewType(int position)。在您发布的代码中，您似乎 returning 2 for your TYPE_SEPARATOR 没有正确检查导航抽屉中元素的位置，这就是为什么您的分隔线出现在导航中主页下方的原因抽屉。您需要检查第 5 个位置，然后 returning 您的 TYPE_SEPARATOR。
我在抽屉中使用了分隔符，方法是在它通过传递不同类型的 ViewHolder 到达我的第 6 个元素时创建一个新布局：
public int getItemViewType(int position) {
if (position == 0) {
return TYPE_HEADER;
} else if (position>0 && position <6) {
return TYPE_TAG;
} else if (position ==6) {
return TYPE_DIVIDER;
}
else
return TYPE_ICON;
}
在我的 ViewHolder 构造函数中：
public ViewHolder(View itemView, int viewType) {
super(itemView);
if(viewType == TYPE_HEADER)
{
name = (TextView) itemView.findViewById(R.id.name);
email = (TextView) itemView.findViewById(R.id.email);
profile = (ImageView) itemView.findViewById(R.id.image_view);
holderId = 0;
}
if (viewType == TYPE_TAG)
{
tagText = (TextView) itemView.findViewById(R.id.tag);
holderId = 1;
}
if(viewType == TYPE_ICON)
{
iconText = (TextView) itemView.findViewById(R.id.rowText);
icon = (ImageView) itemView.findViewById(R.id.rowIcon);
holderId = 2;
}
if(viewType == TYPE_DIVIDER)
{
dividerText = (TextView) itemView.findViewById(R.id.rowText);
dividerIcon = (ImageView) itemView.findViewById(R.id.rowIcon);
holderId = 3;
}
}
}
在我的 onCreateViewHolder 方法中，我只是为 TYPE_DIVIDER 扩充了一个不同的布局。
希望对您有所帮助。
编辑
我已经创建了一个可用的回收器视图，我不建议为你的分隔线膨胀不同的布局。它给我带来了各种各样的问题。你应该使用 RecyclerView.ItemDecoration。这里有一些关于 SO 的精彩帖子，How to add dividers and spaces between items in RecyclerView?.
我开发了一个 Material 基于设计的导航抽屉，其中包含一个 Header 视图，遵循本教程：How To Make Material Design Navigation Drawer With Header View。
我试图在其下方添加一个带有类别名称的分隔符，但与我的分隔符相对应的数据集位置似乎有问题。这意味着分隔符加载正确，但不在我想要的位置。 基本上我尝试做的是将 "DrawerItem" object 的 ArrayList 传递到 "MyAdapter" class 扩展 RecyclerView。 arraylist 包含所有内容： -header的参数 -项目名称和图标 - 和分隔符，也将自己设计为 DrawerItem object 但只有一个字符串作为标题（在我的例子中 "Others"）。
这是我的代码：
DrawerItem:
package madapps.materialdesignappbar;
public class DrawerItem {
String ItemName;
int imgResID;
String title;
String name ;
String email ;
int profile ;
public DrawerItem(String Name, String Email, int profileResID){
name = Name;
email = Email;
profile = profileResID;
}
public DrawerItem(String itemName, int imgResID) {
ItemName = itemName;
this.imgResID = imgResID;
}
//separator case
public DrawerItem(String title) {
this(null, 0);
this.title = title;
this.ItemName = "separator";
}
public String getTitle(){
return title;
}
public void setTitle(String title){
this.title = title;
}
public String getItemName() {
return ItemName;
}
public int getImgResID() {
return imgResID;
}
public void setItemName(String itemName) {
this.ItemName = itemName;
}
public void setImgResID(int imgResID) {
this.imgResID = imgResID;
}
public void setName(String Name){
this.name = Name;
}
public void setEmail(String Email){
this.email = Email;
}
public void setProfile(int Profile){
this.profile = Profile;
}
public String getName(){
return name;
}
public String getEmail(){
return email;
}
public int getProfile(){
return profile;
}
}
MyAdapter
package madapps.materialdesignappbar;
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private static final int TYPE_HEADER = 0; // Declaring Variable to Understand which View is being worked on
// IF the view under inflation and population is header or Item
private static final int TYPE_ITEM = 1;
private static final int TYPE_SEPARATOR = 2;
private ArrayList<DrawerItem> data;
MyAdapter(ArrayList<DrawerItem> Data){
// MyAdapter Constructor with titles and icons parameter
// titles, icons, name, email, profile pic are passed from the main activity as we have seen earlier
data = Data;
}
// Creating a ViewHolder which extends the RecyclerView View Holder
// ViewHolder are used to to store the inflated views in order to recycle them
public static class ViewHolder extends RecyclerView.ViewHolder {
int Holderid;
LinearLayout itemLayout;
TextView textView;
ImageView imageView;
ImageView profile;
TextView Name;
TextView email;
TextView drawerTitle;
LinearLayout separatorLayout;
// Creating ViewHolder Constructor with View and viewType As a parameter
public ViewHolder(View itemView, int ViewType) {
super(itemView);
// Here we set the appropriate view in accordance with the
// the view type as passed when the holder object is created
if (ViewType == TYPE_HEADER){
Name = (TextView) itemView.findViewById(R.id.name); // Creating Text View object from header.xml for name
email = (TextView) itemView.findViewById(R.id.email); // Creating Text View object from header.xml for email
profile = (ImageView) itemView.findViewById(R.id.circleView); // Creating Image view object from header.xml for profile pic
Holderid = 0; // Setting holder id = 0 as the object being populated are of type header view
}
if(ViewType == TYPE_ITEM) {
textView = (TextView) itemView.findViewById(R.id.rowText); // Creating TextView object with the id of textView from item_row.xml
imageView = (ImageView) itemView.findViewById(R.id.rowIcon); // Creating ImageView object with the id of ImageView from item_row.xml
Holderid = 1; // setting holder id as 1 as the object being populated are of type item row
}
if(ViewType == TYPE_SEPARATOR){
drawerTitle = (TextView) itemView.findViewById(R.id.drawerTitle);
Holderid = 2;
}
}
}
//Below first we Override the method onCreateViewHolder which is called when the ViewHolder is
//Created, In this method we inflate the item_row.xml layout if the viewType is Type_ITEM or else we inflate header.xml
// if the viewType is TYPE_HEADER
// and pass it to the view holder
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_HEADER) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.header, parent, false); //Inflating the layout
ViewHolder vhHeader = new ViewHolder(v,viewType); //Creating ViewHolder and passing the object of type view
return vhHeader; //returning the object created
}else
if (viewType == TYPE_ITEM) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_row, parent, false); //Inflating the layout
ViewHolder vhItem = new ViewHolder(v, viewType); //Creating ViewHolder and passing the object of type view
return vhItem; // Returning the created object
//inflate your layout and pass it to view holder
}
if (viewType == TYPE_SEPARATOR){
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.separator, parent, false);
ViewHolder vhSeparator = new ViewHolder(v, viewType);
return vhSeparator;
}
return null;
}
/* Next we override a method which is called when the item in a row is needed to be displayed,
@param position tells us item at which position is being constructed to be displayed
@param holder id of the holder object tell us which view type is being created 1 for item row */
@Override
public void onBindViewHolder(MyAdapter.ViewHolder holder, int position) {
if(holder.Holderid==0) {
holder.profile.setImageResource(data.get(0).getProfile()); // Similarly we set the resources for header view
holder.Name.setText(data.get(0).getName());
holder.email.setText(data.get(0).getEmail());
}
if(holder.Holderid == 1) {
// as the list view is 1going to be called after the header view so we decrement the
holder.textView.setText(data.get(position).title);
holder.imageView.setImageResource(data.get(position).imgResID);
}if (holder.Holderid==2){
holder.drawerTitle.setText(data.get(4).getItemName());
}
}
// This method returns the number of items present in the list
@Override
public int getItemCount() {
return data.size();
}
// With the following method we check what type of view is being passed
@Override
public int getItemViewType(int position) {
if (isPositionHeader(position)) {//if position == 0 return true
return TYPE_HEADER; //0
}
if(isSeparator(position)){
return TYPE_SEPARATOR;
}
return TYPE_ITEM;
}
private boolean isSeparator(int position){
return position==2;
}
private boolean isPositionHeader(int position) {
return position == 0;
}
}
如您所见，我正在用三种 objects 填充 DrawerItem 的 ArrayList，顺序为（来自 MainActivity 的代码）：
ArrayList data = new ArrayList<DrawerItem>();
data.add(new DrawerItem("Chris Benois","chris_benois@mail.com",R.mipmap.aka));
data.add( new DrawerItem("Home",R.mipmap.ic_home));
data.add( new DrawerItem("Events",R.mipmap.ic_events));
data.add( new DrawerItem("Mail", R.mipmap.ic_mail));
data.add(new DrawerItem("Others"));
data.add( new DrawerItem("Shop", R.mipmap.ic_shop));
data.add( new DrawerItem("Travel", R.mipmap.ic_travel));
问题是我的 "separator" 分隔符没有出现在我想要的位置（就在 "Shop" 项目之前），但出现在其他地方，如图所示：
如何将它移动到我想要的位置？
不知道您是否找到了解决方案，但由于您的问题帮助我了解了回收站的观点，我想我会看看我是否可以 return 帮个忙。
我发现 ViewHolder class 中最重要的方法是 getItemViewType(int position)。在您发布的代码中，您似乎 returning 2 for your TYPE_SEPARATOR 没有正确检查导航抽屉中元素的位置，这就是为什么您的分隔线出现在导航中主页下方的原因抽屉。您需要检查第 5 个位置，然后 returning 您的 TYPE_SEPARATOR。
我在抽屉中使用了分隔符，方法是在它通过传递不同类型的 ViewHolder 到达我的第 6 个元素时创建一个新布局：
public int getItemViewType(int position) {
if (position == 0) {
return TYPE_HEADER;
} else if (position>0 && position <6) {
return TYPE_TAG;
} else if (position ==6) {
return TYPE_DIVIDER;
}
else
return TYPE_ICON;
}
在我的 ViewHolder 构造函数中：
public ViewHolder(View itemView, int viewType) {
super(itemView);
if(viewType == TYPE_HEADER)
{
name = (TextView) itemView.findViewById(R.id.name);
email = (TextView) itemView.findViewById(R.id.email);
profile = (ImageView) itemView.findViewById(R.id.image_view);
holderId = 0;
}
if (viewType == TYPE_TAG)
{
tagText = (TextView) itemView.findViewById(R.id.tag);
holderId = 1;
}
if(viewType == TYPE_ICON)
{
iconText = (TextView) itemView.findViewById(R.id.rowText);
icon = (ImageView) itemView.findViewById(R.id.rowIcon);
holderId = 2;
}
if(viewType == TYPE_DIVIDER)
{
dividerText = (TextView) itemView.findViewById(R.id.rowText);
dividerIcon = (ImageView) itemView.findViewById(R.id.rowIcon);
holderId = 3;
}
}
}
在我的 onCreateViewHolder 方法中，我只是为 TYPE_DIVIDER 扩充了一个不同的布局。
希望对您有所帮助。
编辑
我已经创建了一个可用的回收器视图，我不建议为你的分隔线膨胀不同的布局。它给我带来了各种各样的问题。你应该使用 RecyclerView.ItemDecoration。这里有一些关于 SO 的精彩帖子，How to add dividers and spaces between items in RecyclerView?.