Android 使用okhttp从异步调用填充列表视图
在androidstudio中,我试图创建一个片段,在该片段上显示一个项目列表,该项目是我使用okhttp从Http调用中获得的 问题是我的适配器似乎不工作。我没有任何错误,但是我的列表没有显示。Http调用本身就起作用了,我得到了一个汽车品牌列表,该列表映射到使用gson生成的类型列表 以下是我目前掌握的情况:Android 使用okhttp从异步调用填充列表视图,android,listview,okhttp3,Android,Listview,Okhttp3,在androidstudio中,我试图创建一个片段,在该片段上显示一个项目列表,该项目是我使用okhttp从Http调用中获得的 问题是我的适配器似乎不工作。我没有任何错误,但是我的列表没有显示。Http调用本身就起作用了,我得到了一个汽车品牌列表,该列表映射到使用gson生成的类型列表 以下是我目前掌握的情况: public class MakeFragment extends Fragment { private List<Make> allMake = new ArrayLi
public class MakeFragment extends Fragment {
private List<Make> allMake = new ArrayList<>();
ListView listView;
MakeAdapter adapter;
private OnFragmentInteractionListener mListener;
public MakeFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View root = inflater.inflate(R.layout.fragment_make, container, false);
listView = (ListView) root.findViewById(R.id.make_list);
adapter = new MakeAdapter(allMake,getContext());
listView.setAdapter(adapter);
new MyTask().execute();
return root;
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
public class MyTask extends AsyncTask<Void,Void,List<Make>> {
@Override
protected List<Make> doInBackground(Void... voids) {
ImaApi api = new ImaApiImpl();
return api.getAllMake();
}
@Override
protected void onPostExecute(List<Make> result) {
super.onPostExecute(result);
allMake.addAll(result);
adapter.notifyDataSetChanged();
}
}}
public class MakeAdapter extends BaseAdapter{
List<Make> list = new ArrayList<>();
Context context;
public MakeAdapter(List<Make> list, Context context) {
this.list = list;
this.context = context;
}
public void setList(List<Make> list ){
this.list = list;
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int i) {
return list.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
ViewHolder viewHolder;
if (convertView == null){
View view = LayoutInflater.from(context).inflate(R.layout.make_list_item,parent,false);
viewHolder = new ViewHolder(view);
view.setTag(viewHolder);
}else{
viewHolder = (ViewHolder) convertView.getTag();
}
Make make = list.get(position);
viewHolder.textView.setText(make.name);
return viewHolder.itemView;
}
public static class ViewHolder{
TextView textView;
View itemView;
public ViewHolder(View itemView) {
this.itemView = itemView;
textView = itemView.findViewById(R.id.text_view);
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MakeFragment">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="dasfaddsa" />
<ListView
android:id="@+id/make_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="visible" />
</FrameLayout>
public类MakeFragment扩展了Fragment{
private List allMake=new ArrayList();
列表视图列表视图;
MakeAdapter适配器;
私有OnFragmentInteractionListener mListener;
公共MakeFragment(){
//必需的空公共构造函数
}
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
}
@凌驾
创建视图上的公共视图(布局、充气机、视图组容器、,
Bundle savedInstanceState){
//为该碎片膨胀布局
视图根=充气机。充气(R.layout.fragment\u make,容器,假);
listView=(listView)root.findViewById(R.id.make_list);
adapter=newmakeadapter(allMake,getContext());
setAdapter(适配器);
新建MyTask().execute();
返回根;
}
@凌驾
公共void-onAttach(上下文){
super.onAttach(上下文);
if(OnFragmentInteractionListener的上下文实例){
mListener=(OnFragmentInteractionListener)上下文;
}否则{
抛出新的RuntimeException(context.toString()
+“必须实现OnFragmentInteractionListener”);
}
}
@凌驾
公共无效连接(){
super.onDetach();
mListener=null;
}
FragmentInteractionListener上的公共接口{
//TODO:更新参数类型和名称
void onFragmentInteraction(Uri);
}
公共类MyTask扩展了AsyncTask{
@凌驾
受保护列表背景(无效…无效){
ImaApi=新的imaapimpl();
返回api.getAllMake();
}
@凌驾
受保护的void onPostExecute(列表结果){
super.onPostExecute(结果);
allMake.addAll(结果);
adapter.notifyDataSetChanged();
}
}}
我的适配器:
public class MakeFragment extends Fragment {
private List<Make> allMake = new ArrayList<>();
ListView listView;
MakeAdapter adapter;
private OnFragmentInteractionListener mListener;
public MakeFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View root = inflater.inflate(R.layout.fragment_make, container, false);
listView = (ListView) root.findViewById(R.id.make_list);
adapter = new MakeAdapter(allMake,getContext());
listView.setAdapter(adapter);
new MyTask().execute();
return root;
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
public class MyTask extends AsyncTask<Void,Void,List<Make>> {
@Override
protected List<Make> doInBackground(Void... voids) {
ImaApi api = new ImaApiImpl();
return api.getAllMake();
}
@Override
protected void onPostExecute(List<Make> result) {
super.onPostExecute(result);
allMake.addAll(result);
adapter.notifyDataSetChanged();
}
}}
public class MakeAdapter extends BaseAdapter{
List<Make> list = new ArrayList<>();
Context context;
public MakeAdapter(List<Make> list, Context context) {
this.list = list;
this.context = context;
}
public void setList(List<Make> list ){
this.list = list;
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int i) {
return list.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
ViewHolder viewHolder;
if (convertView == null){
View view = LayoutInflater.from(context).inflate(R.layout.make_list_item,parent,false);
viewHolder = new ViewHolder(view);
view.setTag(viewHolder);
}else{
viewHolder = (ViewHolder) convertView.getTag();
}
Make make = list.get(position);
viewHolder.textView.setText(make.name);
return viewHolder.itemView;
}
public static class ViewHolder{
TextView textView;
View itemView;
public ViewHolder(View itemView) {
this.itemView = itemView;
textView = itemView.findViewById(R.id.text_view);
}
}
}
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MakeFragment">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="dasfaddsa" />
<ListView
android:id="@+id/make_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="visible" />
</FrameLayout>
公共类MakeAdapter扩展了BaseAdapter{
列表=新的ArrayList();
语境;
公共MakeAdapter(列表、上下文){
this.list=列表;
this.context=上下文;
}
公共无效集合列表(列表){
this.list=列表;
}
@凌驾
public int getCount(){
返回list.size();
}
@凌驾
公共对象getItem(int i){
返回列表。获取(i);
}
@凌驾
公共长getItemId(int i){
返回i;
}
@凌驾
公共视图getView(int位置,@Nullable视图convertView,@NonNull视图组父级){
持票人持票人;
if(convertView==null){
视图=布局更平坦。从(上下文)。充气(R.layout.make_list_item,parent,false);
viewHolder=新的viewHolder(视图);
view.setTag(viewHolder);
}否则{
viewHolder=(viewHolder)convertView.getTag();
}
Make Make=list.get(位置);
viewHolder.textView.setText(make.name);
返回viewHolder.itemView;
}
公共静态类视图持有者{
文本视图文本视图;
查看项目视图;
公共视图持有者(视图项视图){
this.itemView=itemView;
textView=itemView.findViewById(R.id.text\u视图);
}
}
}
我的制作列表项目.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="60dp"
android:layout_marginTop="10dp">
<TextView
android:id="@+id/text_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:layout_marginTop="20dp"
android:textSize="20dp"
android:maxLength="5"
android:text=""/>
</android.support.v7.widget.CardView>
. 当我使用调试器时,适配器getCount显示我有43个对象,这是我应该做的,并且从未调用过getView方法
编辑:我正在添加getAllMake()方法来帮助您,但它正在正常工作
@Override
public List<Make> getAllMake() {
Request request = new Request.Builder()
.url(baseUrl + "/api/v1/brand/")
.build();
Response response = null;
String responseBody = "";
try {
response = client.newCall(request).execute();
responseBody = response.body().string();
} catch (IOException e) {
e.printStackTrace();
}
MakeWrapper makeWrapper = gson.fromJson(responseBody, MakeWrapper.class);
return makeWrapper.content;
}
@覆盖
公共列表getAllMake(){
Request Request=newrequest.Builder()
.url(baseUrl+“/api/v1/brand/”)
.build();
响应=空;
字符串responseBody=“”;
试一试{
response=client.newCall(request.execute();
responseBody=response.body().string();
}捕获(IOE异常){
e、 printStackTrace();
}
MakeWrapper=gson.fromJson(responseBody,MakeWrapper.class);
返回makeWrapper.content;
}
试试这个
public class MakeFragment extends Fragment {
private List<Make> allMake = new ArrayList<>();
ListView listView;
MakeAdapter adapter;
private OnFragmentInteractionListener mListener;
public MakeFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View root = inflater.inflate(R.layout.fragment_make, container, false);
listView = (ListView) root.findViewById(R.id.make_list);
adapter = new MakeAdapter(allMake,getContext());
listView.setAdapter(adapter);
new MyTask().execute();
return root;
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
public class MyTask extends AsyncTask<Void,Void,List<Make>> {
@Override
protected List<Make> doInBackground(Void... voids) {
ImaApi api = new ImaApiImpl();
return api.getAllMake();
}
@Override
protected void onPostExecute(List<Make> result) {
super.onPostExecute(result);
allMake.addAll(result);
adapter.notifyDataSetChanged();
}
}}
public类MakeFragment扩展了Fragment{
private List allMake=new ArrayList();
列表视图列表视图;
MakeAdapter适配器;
私有OnFragmentInteractionListener mListener;
公共MakeFragment(){
//必需的空公共构造函数
}
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
}
@凌驾
创建视图上的公共视图(布局、充气机、视图组容器、,
Bundle savedInstanceState){
//为该碎片膨胀布局
视图根=充气机。充气(R.layout.fragment\u make,容器,假);
listView=(listView)root.findViewById(R.id.make_list);
adapter=newmakeadapter(allMake,getContext());
setAdapter(适配器);
新建MyTask().execute();
返回根;
}
@凌驾
公共void-onAttach(上下文){
super.onAttach(上下文);
if(OnFragmentInteractionListener的上下文实例){
mListener=(OnFragmentInteractionListener)上下文;
}否则{
抛出新的RuntimeException(context.toString()
+“必须实现OnFragmentInteractionListener”);
}
}
@凌驾
公共无效连接(){
super.onDetach();
mListener=null;
}
FragmentInteractionListener上的公共接口{
//TODO:更新参数类型和名称
void onFragmentInteraction(Uri);
}
公共类MyTask扩展了AsyncTask{
@凌驾
受保护列表背景(无效…无效){
ImaApi=新的imaapimpl();
返回api.getAllMake();
}