Android 使用JSON填充微调器,即使没有错误,也不会显示任何内容
我认为我面临的问题是,ui在从后端获取数据之前先绘制我的布局图,它是旋转器。。。所以我需要先阻止它并等待我的数据,但我不知道怎么做 从后端检索到的json数据如下所示Android 使用JSON填充微调器,即使没有错误,也不会显示任何内容,android,json,Android,Json,我认为我面临的问题是,ui在从后端获取数据之前先绘制我的布局图,它是旋转器。。。所以我需要先阻止它并等待我的数据,但我不知道怎么做 从后端检索到的json数据如下所示 [ { "id": 3, "nom": "xxxx", "etat": 0 } ] // URL String URL= AppConfig.URL_GetFolders; Spinner spinner; ArrayList<String> Folde
[
{
"id": 3,
"nom": "xxxx",
"etat": 0
}
]
// URL
String URL= AppConfig.URL_GetFolders;
Spinner spinner;
ArrayList<String> Folders;
NavigationView navigationView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.folder_activity);
init(savedInstanceState);
// declaring spinner refs
Folders=new ArrayList<>();
spinner=(Spinner)findViewById(R.id.folder_Name);
// Spinner section
loadSpinnerFolders(URL);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
String folder = spinner.getItemAtPosition(spinner.getSelectedItemPosition()).toString();
Toast.makeText(getApplicationContext(),folder,Toast.LENGTH_LONG).show();
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
// DO Nothing here
}
});
}
private void loadSpinnerFolders (String url) {
RequestQueue requestQueue=Volley.newRequestQueue(getApplicationContext());
StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try{
JSONObject jsonObject = new JSONObject(response);
JSONArray jsonArray=jsonObject.getJSONArray("data");
for(int i=0;i<jsonArray.length();i++){
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
String dossier = jsonObject1.getString("nom");
Folders.add(dossier);
}
spinner.setAdapter(new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_dropdown_item, Folders));
}catch (JSONException e){
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
int socketTimeout = 30000;
RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
stringRequest.setRetryPolicy(policy);
requestQueue.add(stringRequest);
}
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/main_activity_DrawerLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<!-- The main content view -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include layout="@layout/toolbar" />
<FrameLayout
android:id="@+id/main_activity_content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Spinner
android:id="@+id/folder_Name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:paddingBottom="20dp"
android:paddingEnd="20dp"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:paddingStart="20dp"
android:paddingTop="20dp" />
</FrameLayout>
</LinearLayout>
</android.support.v4.widget.DrawerLayout>
我正在尝试使用从后端获得的JSON数据填充一个微调器。即使我没有得到任何错误,但仍然没有得到我想要的结果
我的课是这样的,
[
{
"id": 3,
"nom": "xxxx",
"etat": 0
}
]
// URL
String URL= AppConfig.URL_GetFolders;
Spinner spinner;
ArrayList<String> Folders;
NavigationView navigationView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.folder_activity);
init(savedInstanceState);
// declaring spinner refs
Folders=new ArrayList<>();
spinner=(Spinner)findViewById(R.id.folder_Name);
// Spinner section
loadSpinnerFolders(URL);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
String folder = spinner.getItemAtPosition(spinner.getSelectedItemPosition()).toString();
Toast.makeText(getApplicationContext(),folder,Toast.LENGTH_LONG).show();
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
// DO Nothing here
}
});
}
private void loadSpinnerFolders (String url) {
RequestQueue requestQueue=Volley.newRequestQueue(getApplicationContext());
StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try{
JSONObject jsonObject = new JSONObject(response);
JSONArray jsonArray=jsonObject.getJSONArray("data");
for(int i=0;i<jsonArray.length();i++){
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
String dossier = jsonObject1.getString("nom");
Folders.add(dossier);
}
spinner.setAdapter(new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_dropdown_item, Folders));
}catch (JSONException e){
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
int socketTimeout = 30000;
RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
stringRequest.setRetryPolicy(policy);
requestQueue.add(stringRequest);
}
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/main_activity_DrawerLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<!-- The main content view -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include layout="@layout/toolbar" />
<FrameLayout
android:id="@+id/main_activity_content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Spinner
android:id="@+id/folder_Name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:paddingBottom="20dp"
android:paddingEnd="20dp"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:paddingStart="20dp"
android:paddingTop="20dp" />
</FrameLayout>
</LinearLayout>
</android.support.v4.widget.DrawerLayout>
//URL
字符串URL=AppConfig.URL\u GetFolders;
纺纱机;
ArrayList文件夹;
导航视图导航视图;
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.folder_活动);
初始化(savedInstanceState);
//声明微调器引用
Folders=newarraylist();
微调器=(微调器)findViewById(R.id.folder\u Name);
//旋转部分
加载SpinnerFolders(URL);
spinner.setOnItemSelectedListener(新的AdapterView.OnItemSelectedListener(){
@凌驾
已选择公共视图(AdapterView AdapterView、View视图、int i、long l){
String folder=spinner.getItemAtPosition(spinner.getSelectedItemPosition()).toString();
Toast.makeText(getApplicationContext(),文件夹,Toast.LENGTH_LONG.show();
}
@凌驾
未选择公共无效(AdapterView AdapterView){
//在这里什么也不做
}
});
}
我的微调器函数是这样的
[
{
"id": 3,
"nom": "xxxx",
"etat": 0
}
]
// URL
String URL= AppConfig.URL_GetFolders;
Spinner spinner;
ArrayList<String> Folders;
NavigationView navigationView;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.folder_activity);
init(savedInstanceState);
// declaring spinner refs
Folders=new ArrayList<>();
spinner=(Spinner)findViewById(R.id.folder_Name);
// Spinner section
loadSpinnerFolders(URL);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
String folder = spinner.getItemAtPosition(spinner.getSelectedItemPosition()).toString();
Toast.makeText(getApplicationContext(),folder,Toast.LENGTH_LONG).show();
}
@Override
public void onNothingSelected(AdapterView<?> adapterView) {
// DO Nothing here
}
});
}
private void loadSpinnerFolders (String url) {
RequestQueue requestQueue=Volley.newRequestQueue(getApplicationContext());
StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try{
JSONObject jsonObject = new JSONObject(response);
JSONArray jsonArray=jsonObject.getJSONArray("data");
for(int i=0;i<jsonArray.length();i++){
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
String dossier = jsonObject1.getString("nom");
Folders.add(dossier);
}
spinner.setAdapter(new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_dropdown_item, Folders));
}catch (JSONException e){
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
int socketTimeout = 30000;
RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
stringRequest.setRetryPolicy(policy);
requestQueue.add(stringRequest);
}
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/main_activity_DrawerLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<!-- The main content view -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include layout="@layout/toolbar" />
<FrameLayout
android:id="@+id/main_activity_content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Spinner
android:id="@+id/folder_Name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:paddingBottom="20dp"
android:paddingEnd="20dp"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:paddingStart="20dp"
android:paddingTop="20dp" />
</FrameLayout>
</LinearLayout>
</android.support.v4.widget.DrawerLayout>
private void loadSpinnerFolders(字符串url){
RequestQueue RequestQueue=Volley.newRequestQueue(getApplicationContext());
StringRequest StringRequest=新建StringRequest(Request.Method.GET,url,new Response.Listener()){
@凌驾
公共void onResponse(字符串响应){
试一试{
JSONObject JSONObject=新JSONObject(响应);
JSONArray JSONArray=jsonObject.getJSONArray(“数据”);
对于(inti=0;iHandler…)
这将等待5秒钟。您可以通过编辑5000进行调整
1000=1秒
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
public void run() {
// yourMethod();
}
}, 5000);
您还可以执行异步任务
private class MethodNameHere extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
//THINGS TO DO BEFORE THE CODE STARTS (create a new List)
}
@Override
protected Void doInBackground(Void... arg0) {
//things to do because you draw the layout in post
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
//draw the view
}
}
此外,如果微调器值没有更改,请不要从服务器获取它们。将它们存储在本地
这是一种使用列表并将其放入微调器的简单方法
Spinner spinner;
List<String> spinnerList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
spinner = findViewById(R.id.spinner);
spinnerList = new ArrayList<>();
spinnerList.add("test 1");
spinnerList.add("test 2");
spinnerList.add("test 3");
spinnerList.add("test 4");
spinnerList.add("test 5");
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>
(this, android.R.layout.simple_spinner_item, spinnerList);
spinner.setAdapter(spinnerArrayAdapter);
}
微调器微调器;
列表喷丝头列表;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
微调器=findViewById(R.id.spinner);
喷丝头列表=新的ArrayList();
喷丝头列表。添加(“试验1”);
喷丝头列表。添加(“试验2”);
喷丝头列表。添加(“试验3”);
喷丝头列表。添加(“试验4”);
喷丝头列表。添加(“试验5”);
ArrayAdapter SpinnerayAdapter=新的ArrayAdapter
(这是android.R.layout.simple\u spinner\u项目,spinnerList);
spinner.setAdapter(SpinNearrayaAdapter);
}
在预执行时,创建一个新列表
现在,在您的例子中,您需要获得响应,遍历数组,并将项目添加到列表中
在波斯特…做这个
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>
(this, android.R.layout.simple_spinner_item, spinnerList);
spinner.setAdapter(spinnerArrayAdapter);
ArrayAdapter微调器ArrayAdapter=新的ArrayAdapter
(这是android.R.layout.simple\u spinner\u项目,spinnerList);
spinner.setAdapter(SpinNearrayaAdapter);
您能显示完整的json吗?因为您的代码会显示jsonObject.getJSONArray(“数据”)..但是没有数据阵列我很抱歉我只是编辑了它,我得到的json会调试它。应该可以工作。文件夹的大小是多少?在循环之后检查它。我面临的问题是ui在从后端获取数据之前先绘制我的布局,它是微调器…所以我需要阻止它并等待我的数据,但我没有知道如何添加处理程序。我将为代码添加一个答案。@brxnzaz检查底部的更新。不要想太多。这很容易。