为什么我的 ListAdapter 没有显示任何数据?
Why is my ListAdapter not showing any data?
我正在尝试用 JSON 数据源中的项目列表填充视图。
我似乎无法让适配器在我的列表中显示 JSON 数据。这是我到目前为止所做的。
MainActivity.java
package com.todoapp.android.json;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
public class MainActivity extends ListActivity {
private ProgressDialog pDialog;
// JSON Node names
private static final String TAG_ITEM = "items";
private static final String TAG_INDEX = "index";
private static final String TAG_NAME = "name";
// contacts JSONArray
JSONArray items = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> contactList = new ArrayList<>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Calling async task to get json
new GetContacts().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetContacts extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
String jsonStr = "{\"items\":[{\"index\":1,\"name\":\"Bobby\",\"events\":[{\"index\":19,\"email\":\"louis@hardy.eg\"},{\"index\":13,\"email\":\"cynthia@mills.mc\"},{\"index\":0,\"email\":\"leo@graham.kp\"}]}]}";
if (jsonStr != null) {
try {
Log.d("Response: ", "> " + jsonStr);
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
items = jsonObj.getJSONArray(TAG_ITEM);
// looping through All Contacts
for (int i = 0; i < items.length(); i++) {
JSONObject c = items.getJSONObject(i);
//String id = c.getString(TAG_INDEX);
//String index = c.getString(TAG_INDEX);
String index = String.valueOf(c.getInt(TAG_INDEX));
String name = c.getString(TAG_NAME);
HashMap<String, String> contact = new HashMap<>();
// adding each child node to HashMap key => value
contact.put(TAG_INDEX, index);
contact.put(TAG_NAME, name);
// adding contact to contact list
contactList.add(contact);
}
} catch (JSONException e) {
Log.e("foo", "error", e);
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, contactList,
R.layout.list_item, new String[] { TAG_INDEX, TAG_NAME}, new int[] { R.id.index,
R.id.name });
setListAdapter(adapter);
}
}
}
list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="10dp"
android:paddingLeft="10dp"
android:paddingRight="10dp" >
<!-- Name Label -->
<TextView
android:id="@+id/index"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:paddingTop="6dip"
android:textColor="#43bd00"
android:textSize="16sp"
android:textStyle="bold" />
<!-- Email label -->
<TextView
android:id="@+id/name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:textColor="#acacac" />
</LinearLayout>
content_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<!-- Main ListView
Always give id value as list(@android:id/list)
-->
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.todoapp.android.json.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
android:src="@android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
我在 logcat 中唯一得到的是 "Verbose" 模式是
12-15 12:13:58.152 18184-18184/? I/art: Late-enabling -Xcheck:jni
12-15 12:13:58.235 18184-18184/com.todoapp.android.json D/ContextHelper: convertTheme. context->name=com.todoapp.android.json themeResourceId=2131230766
12-15 12:13:58.245 18184-18184/com.todoapp.android.json I/PhoneWindow: [generateLayout] setColorNavigationBar => color=0x ff000001
12-15 12:13:58.252 18184-18184/com.todoapp.android.json D/PhoneWindowEx: [PWEx][generateLayout] setNavigationBarColor2 : colors=0xff000000
12-15 12:13:58.252 18184-18184/com.todoapp.android.json I/PhoneWindow: [setNavigationBarColor2] color=0x ff000000
12-15 12:13:58.351 18184-18184/com.todoapp.android.json I/PhoneWindow: [generateLayout] setColorNavigationBar => color=0x ff000001
12-15 12:13:58.353 18184-18184/com.todoapp.android.json D/PhoneWindowEx: [PWEx][generateLayout] setNavigationBarColor2 : colors=0xff000000
12-15 12:13:58.353 18184-18184/com.todoapp.android.json I/PhoneWindow: [setNavigationBarColor2] color=0x ff000000
12-15 12:13:58.376 18184-18214/com.todoapp.android.json D/OpenGLRenderer: Render dirty regions requested: false
12-15 12:13:58.377 18184-18214/com.todoapp.android.json E/[DRVB][EXT][UTIL]: disp_only_chk: DRVB CHECK PROCESS DONE ! STATUS (0/0x2002)
12-15 12:13:58.377 18184-18214/com.todoapp.android.json W/[DRVB]: sec_drv_base_check: DRVB PROCESS STATUS = 0x2002
12-15 12:13:58.381 18184-18214/com.todoapp.android.json I/OpenGLRenderer: Initialized EGL, version 1.4
12-15 12:13:58.382 18184-18214/com.todoapp.android.json D/OpenGLRenderer: Enabling debug mode 0
12-15 12:13:58.387 18184-18184/com.todoapp.android.json D/Atlas: Validating map...
12-15 12:13:58.389 18184-18214/com.todoapp.android.json I/[MALI][Gralloc]: dlopen libsec_mem.so fail
12-15 12:13:58.399 18184-18220/com.todoapp.android.json D/Response:: > {"items":[{"index":1,"name":"Bobby","events":[{"index":19,"email":"louis@hardy.eg"},{"index":13,"email":"cynthia@mills.mc"},{"index":0,"email":"leo@graham.kp"}]}]}
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
12-15 12:13:58.596 18184-18184/com.todoapp.android.json I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@f8bfa22 time:6011123
`
实体 phone 上的应用程序启动正常,但随后为空白。任何指针?我的 json 文件如下所示:
json数据
{
"items": [
{
"index": 1,
"name": "Bobby",
"events": [
{
"index": 19,
"email": "louis@hardy.eg"
},
{
"index": 13,
"email": "cynthia@mills.mc"
},
{
"index": 0,
"email": "leo@graham.kp"
}
]
}
}
根据您发布的JSON
:
private static final String TAG_ITEM = "item";
应该是
private static final String TAG_ITEM = "items";
index
是 int
而不是 String
,这一行
String index = c.getString(TAG_INDEX);
主要是导致解析失败。将其更改为
String index = String.valueOf(c.getInt(TAG_INDEX));
我想这可能是由于 JSONException。
尝试使用以下代码和 运行
String jsonString = "{\n\t\\"items\\": [\n\t\t{\n\t\t\t\\"index\\": 1,\n\t\t\t\\"name\\": \\"Bobby\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 19,\n\t\t\t\t\t\\"email\\": \\"louis@hardy.eg\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 13,\n\t\t\t\t\t\\"email\\": \\"cynthia@mills.mc\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 0,\n\t\t\t\t\t\\"email\\": \\"leo@graham.kp\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 2,\n\t\t\t\\"name\\": \\"Maxine\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 14,\n\t\t\t\t\t\\"email\\": \\"miriam@horne.mo\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 20,\n\t\t\t\t\t\\"email\\": \\"danny@joyce.ro\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 25,\n\t\t\t\t\t\\"email\\": \\"christina@davenport.fo\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 3,\n\t\t\t\\"name\\": \\"Ruth\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 1,\n\t\t\t\t\t\\"email\\": \\"heather@kirk.bm\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 29,\n\t\t\t\t\t\\"email\\": \\"kim@middleton.ve\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 2,\n\t\t\t\t\t\\"email\\": \\"harold@arthur.net\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 4,\n\t\t\t\\"name\\": \\"Brandon\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 3,\n\t\t\t\t\t\\"email\\": \\"danny@parrott.eg\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 5,\n\t\t\t\t\t\\"email\\": \\"sarah@underwood.net\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 11,\n\t\t\t\t\t\\"email\\": \\"bonnie@banks.ye\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 5,\n\t\t\t\\"name\\": \\"Kristina\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 18,\n\t\t\t\t\t\\"email\\": \\"frances@law.mf\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 15,\n\t\t\t\t\t\\"email\\": \\"nancy@o.mo\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 6,\n\t\t\t\t\t\\"email\\": \\"ben@holden.um\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 6,\n\t\t\t\\"name\\": \\"Keith\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 10,\n\t\t\t\t\t\\"email\\": \\"alfred@baldwin.za\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 9,\n\t\t\t\t\t\\"email\\": \\"courtney@hinson.us\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 7,\n\t\t\t\t\t\\"email\\": \\"tracey@keller.li\\"\n\t\t\t\t}\n\t\t\t]\n\t\t}\n\t]\n}\n";
通过替换空格、换行符等将其转换为正确的 json 格式
String jsonStr = jsonString.replace("\n", "").replace("\t", "").replace("\'", "").replace("\", "");
并替换
private static final String TAG_ITEM = "item";
与
private static final String TAG_ITEM = "items";
我正在尝试用 JSON 数据源中的项目列表填充视图。 我似乎无法让适配器在我的列表中显示 JSON 数据。这是我到目前为止所做的。
MainActivity.java
package com.todoapp.android.json;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
public class MainActivity extends ListActivity {
private ProgressDialog pDialog;
// JSON Node names
private static final String TAG_ITEM = "items";
private static final String TAG_INDEX = "index";
private static final String TAG_NAME = "name";
// contacts JSONArray
JSONArray items = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> contactList = new ArrayList<>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Calling async task to get json
new GetContacts().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetContacts extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
String jsonStr = "{\"items\":[{\"index\":1,\"name\":\"Bobby\",\"events\":[{\"index\":19,\"email\":\"louis@hardy.eg\"},{\"index\":13,\"email\":\"cynthia@mills.mc\"},{\"index\":0,\"email\":\"leo@graham.kp\"}]}]}";
if (jsonStr != null) {
try {
Log.d("Response: ", "> " + jsonStr);
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
items = jsonObj.getJSONArray(TAG_ITEM);
// looping through All Contacts
for (int i = 0; i < items.length(); i++) {
JSONObject c = items.getJSONObject(i);
//String id = c.getString(TAG_INDEX);
//String index = c.getString(TAG_INDEX);
String index = String.valueOf(c.getInt(TAG_INDEX));
String name = c.getString(TAG_NAME);
HashMap<String, String> contact = new HashMap<>();
// adding each child node to HashMap key => value
contact.put(TAG_INDEX, index);
contact.put(TAG_NAME, name);
// adding contact to contact list
contactList.add(contact);
}
} catch (JSONException e) {
Log.e("foo", "error", e);
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, contactList,
R.layout.list_item, new String[] { TAG_INDEX, TAG_NAME}, new int[] { R.id.index,
R.id.name });
setListAdapter(adapter);
}
}
}
list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="10dp"
android:paddingLeft="10dp"
android:paddingRight="10dp" >
<!-- Name Label -->
<TextView
android:id="@+id/index"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:paddingTop="6dip"
android:textColor="#43bd00"
android:textSize="16sp"
android:textStyle="bold" />
<!-- Email label -->
<TextView
android:id="@+id/name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="2dip"
android:textColor="#acacac" />
</LinearLayout>
content_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<!-- Main ListView
Always give id value as list(@android:id/list)
-->
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.todoapp.android.json.MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="@style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="@layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="@dimen/fab_margin"
android:src="@android:drawable/ic_dialog_email" />
</android.support.design.widget.CoordinatorLayout>
我在 logcat 中唯一得到的是 "Verbose" 模式是
12-15 12:13:58.152 18184-18184/? I/art: Late-enabling -Xcheck:jni
12-15 12:13:58.235 18184-18184/com.todoapp.android.json D/ContextHelper: convertTheme. context->name=com.todoapp.android.json themeResourceId=2131230766
12-15 12:13:58.245 18184-18184/com.todoapp.android.json I/PhoneWindow: [generateLayout] setColorNavigationBar => color=0x ff000001
12-15 12:13:58.252 18184-18184/com.todoapp.android.json D/PhoneWindowEx: [PWEx][generateLayout] setNavigationBarColor2 : colors=0xff000000
12-15 12:13:58.252 18184-18184/com.todoapp.android.json I/PhoneWindow: [setNavigationBarColor2] color=0x ff000000
12-15 12:13:58.351 18184-18184/com.todoapp.android.json I/PhoneWindow: [generateLayout] setColorNavigationBar => color=0x ff000001
12-15 12:13:58.353 18184-18184/com.todoapp.android.json D/PhoneWindowEx: [PWEx][generateLayout] setNavigationBarColor2 : colors=0xff000000
12-15 12:13:58.353 18184-18184/com.todoapp.android.json I/PhoneWindow: [setNavigationBarColor2] color=0x ff000000
12-15 12:13:58.376 18184-18214/com.todoapp.android.json D/OpenGLRenderer: Render dirty regions requested: false
12-15 12:13:58.377 18184-18214/com.todoapp.android.json E/[DRVB][EXT][UTIL]: disp_only_chk: DRVB CHECK PROCESS DONE ! STATUS (0/0x2002)
12-15 12:13:58.377 18184-18214/com.todoapp.android.json W/[DRVB]: sec_drv_base_check: DRVB PROCESS STATUS = 0x2002
12-15 12:13:58.381 18184-18214/com.todoapp.android.json I/OpenGLRenderer: Initialized EGL, version 1.4
12-15 12:13:58.382 18184-18214/com.todoapp.android.json D/OpenGLRenderer: Enabling debug mode 0
12-15 12:13:58.387 18184-18184/com.todoapp.android.json D/Atlas: Validating map...
12-15 12:13:58.389 18184-18214/com.todoapp.android.json I/[MALI][Gralloc]: dlopen libsec_mem.so fail
12-15 12:13:58.399 18184-18220/com.todoapp.android.json D/Response:: > {"items":[{"index":1,"name":"Bobby","events":[{"index":19,"email":"louis@hardy.eg"},{"index":13,"email":"cynthia@mills.mc"},{"index":0,"email":"leo@graham.kp"}]}]}
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
12-15 12:13:58.453 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
12-15 12:13:58.504 18184-18214/com.todoapp.android.json I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
12-15 12:13:58.596 18184-18184/com.todoapp.android.json I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@f8bfa22 time:6011123
`
实体 phone 上的应用程序启动正常,但随后为空白。任何指针?我的 json 文件如下所示:
json数据
{
"items": [
{
"index": 1,
"name": "Bobby",
"events": [
{
"index": 19,
"email": "louis@hardy.eg"
},
{
"index": 13,
"email": "cynthia@mills.mc"
},
{
"index": 0,
"email": "leo@graham.kp"
}
]
}
}
根据您发布的JSON
:
private static final String TAG_ITEM = "item";
应该是
private static final String TAG_ITEM = "items";
index
是 int
而不是 String
,这一行
String index = c.getString(TAG_INDEX);
主要是导致解析失败。将其更改为
String index = String.valueOf(c.getInt(TAG_INDEX));
我想这可能是由于 JSONException。
尝试使用以下代码和 运行
String jsonString = "{\n\t\\"items\\": [\n\t\t{\n\t\t\t\\"index\\": 1,\n\t\t\t\\"name\\": \\"Bobby\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 19,\n\t\t\t\t\t\\"email\\": \\"louis@hardy.eg\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 13,\n\t\t\t\t\t\\"email\\": \\"cynthia@mills.mc\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 0,\n\t\t\t\t\t\\"email\\": \\"leo@graham.kp\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 2,\n\t\t\t\\"name\\": \\"Maxine\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 14,\n\t\t\t\t\t\\"email\\": \\"miriam@horne.mo\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 20,\n\t\t\t\t\t\\"email\\": \\"danny@joyce.ro\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 25,\n\t\t\t\t\t\\"email\\": \\"christina@davenport.fo\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 3,\n\t\t\t\\"name\\": \\"Ruth\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 1,\n\t\t\t\t\t\\"email\\": \\"heather@kirk.bm\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 29,\n\t\t\t\t\t\\"email\\": \\"kim@middleton.ve\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 2,\n\t\t\t\t\t\\"email\\": \\"harold@arthur.net\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 4,\n\t\t\t\\"name\\": \\"Brandon\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 3,\n\t\t\t\t\t\\"email\\": \\"danny@parrott.eg\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 5,\n\t\t\t\t\t\\"email\\": \\"sarah@underwood.net\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 11,\n\t\t\t\t\t\\"email\\": \\"bonnie@banks.ye\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 5,\n\t\t\t\\"name\\": \\"Kristina\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 18,\n\t\t\t\t\t\\"email\\": \\"frances@law.mf\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 15,\n\t\t\t\t\t\\"email\\": \\"nancy@o.mo\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 6,\n\t\t\t\t\t\\"email\\": \\"ben@holden.um\\"\n\t\t\t\t}\n\t\t\t]\n\t\t},\n\t\t{\n\t\t\t\\"index\\": 6,\n\t\t\t\\"name\\": \\"Keith\\",\n\t\t\t\\"events\\": [\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 10,\n\t\t\t\t\t\\"email\\": \\"alfred@baldwin.za\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 9,\n\t\t\t\t\t\\"email\\": \\"courtney@hinson.us\\"\n\t\t\t\t},\n\t\t\t\t{\n\t\t\t\t\t\\"index\\": 7,\n\t\t\t\t\t\\"email\\": \\"tracey@keller.li\\"\n\t\t\t\t}\n\t\t\t]\n\t\t}\n\t]\n}\n";
通过替换空格、换行符等将其转换为正确的 json 格式
String jsonStr = jsonString.replace("\n", "").replace("\t", "").replace("\'", "").replace("\", "");
并替换
private static final String TAG_ITEM = "item";
与
private static final String TAG_ITEM = "items";