我试图将ListView放入片段中，但我的应用崩溃了。
我跟着this guide学习了如何在活动中放置ListView，但是我想把它放在一个片段中，所以我稍微改了一下代码。
这是我的片段：
公共类FaqFragment扩展了Fragment {
public static Fragment newInstance() {
FaqFragment fragment = new FaqFragment();
Bundle args = new Bundle();
fragment.setArguments(args);
return fragment;
}
private ListView listView1;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_faq, container, false);
Element element_data[] = new Element[]
{
new Element(R.drawable.goccia, "Goccia1"),
new Element(R.drawable.goccia, "Goccia2"),
new Element(R.drawable.goccia, "Goccia3"),
new Element(R.drawable.goccia, "Goccia4"),
new Element(R.drawable.goccia, "Goccia5")
};
ElementAdapter adapter = new ElementAdapter(getActivity(), android.R.layout.simple_list_item_1, element_data);
listView1 = (ListView)v.findViewById(R.id.listView1);
View header = (View)getLayoutInflater(savedInstanceState).inflate(R.layout.element, null);
listView1.addHeaderView(header);
listView1.setAdapter(adapter);
return v;
}
这是我的ArrayAdapter：
public class ElementAdapter extends ArrayAdapter<Element>{
FragmentActivity context;
int layoutResourceId;
Element data[] = null;
public ElementAdapter(FragmentActivity fragmentActivity, int layoutResourceId, Element[] data) {
super(fragmentActivity, layoutResourceId, data);
this.layoutResourceId = layoutResourceId;
this.context = fragmentActivity;
this.data = data;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
WeatherHolder holder = null;
if(row == null)
{
LayoutInflater inflater = ((FragmentActivity)context).getLayoutInflater();
row = inflater.inflate(layoutResourceId, parent, false);
holder = new WeatherHolder();
holder.imgIcon = (ImageView)row.findViewById(R.id.imgIcon);
holder.txtTitle = (TextView)row.findViewById(R.id.txtTitle);
row.setTag(holder);
}
else
{
holder = (WeatherHolder)row.getTag();
}
Element element = data[position];
holder.txtTitle.setText(element.title);
holder.imgIcon.setImageResource(element.icon);
return row;
}
static class WeatherHolder
{
ImageView imgIcon;
TextView txtTitle;
}
}
这是我的Element：
public class Element {
public int icon;
public String title;
public Element(){
super();
}
public Element(int icon, String title) {
super();
this.icon = icon;
this.title = title;
}
}
该应用有3个标签，当我滑动到标签时，应用程序崩溃，我已经写过的代码（片段）。
在logcat中存在以下错误：
03-13 11：25：39.455：E / AndroidRuntime（2840）：at com.example.bluhackathon.ElementAdapter.getView（ElementAdapter.java:47）
我尝试删除ArrayAdapter的第47,48和49行，但应用没有崩溃（当然有一个包含空元素的列表。
第47,48,49行：
Element element = data[position];
holder.txtTitle.setText(element.title);
holder.imgIcon.setImageResource(element.icon);
答案 0 :(得分：1)
你可以使用ListFragment来实现它，下面是我实现“将listview放入Fragment，并从MySQL获取数据”的答案，我昨天写了它并希望它可以帮助你解决问题。
package com.ecnu.vendingmachine;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListFragment;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import com.ecnu.vendingmachine.widgets.JSONParser;
public class VendingFragment extends ListFragment {
private String Tag = "VendingFragment";
private static final String TAG_SUCCESS = "success";
private ListView listView;
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jsonParser = new JSONParser();
JSONArray vendingmachine = null;
ArrayList<HashMap<String, String>> vendinglist;
// url to get all products list
MainActivity main = new MainActivity();
private String url_all_vendingmachine = main.getIP()
+ "vendingmachine/get_all_vendingmachine.php";
// products JSONArray
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.vending_main, container, false);
}
@Override
public void onViewCreated (View view, Bundle savedInstanceState) {
vendinglist = new ArrayList<HashMap<String, String>>();
//listView = (ListView) view.findViewById(R.id.list);
listView = getListView();
new get_all_vendingmachine().execute();
}
class get_all_vendingmachine extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Creating Product..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
Log.i(Tag, "pDialog");
}
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
Log.i(Tag, url_all_vendingmachine);
// getting JSON Object
// Note that create product url accepts POST method
JSONObject json = jsonParser.makeHttpRequest(
url_all_vendingmachine, "GET", params);
// check log cat for response
Log.i(Tag, json.toString());
// check for success tag
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// Ada record Data (SUCCESS = 1)
// Getting Array of vendingmachine
vendingmachine = json.getJSONArray("vendings");
// looping through All vendingmachine
for (int i = 0; i < vendingmachine.length(); i++) {
JSONObject c = vendingmachine.getJSONObject(i);
// Storing each json item in variable
String id = c.getString("VMid");
String name = c.getString("Name");
String address = c.getString("Address");
Log.i(Tag, id);
Log.i(Tag, name);
Log.i(Tag, address);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put("VMid", id);
map.put("Name", name);
map.put("Address", address);
// adding HashList to ArrayList
vendinglist.add(map);
}
} else {
// failed to create product
getActivity().finish();
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once done
pDialog.dismiss();
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
// updating listview
// HashMap<String, String>中的key
String[] from = { "Name", "Address", "VMid" };
// list_item.xml中对应的控件ID
int[] to = { R.id.vending_name, R.id.vending_address,
R.id.vending_id };
Log.i(Tag, from[0]);
SimpleAdapter adapter = new SimpleAdapter(getActivity(),
vendinglist, R.layout.vending_list, from, to);
listView.setAdapter(adapter);
}
});
}
}
}
vending_main_xml：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/whiteColor" >
<include
android:id="@+id/layout_buy_title_actionbar"
layout="@layout/headbar_title" />
<ListView
android:id="@id/android:list"
android:layout_below="@id/layout_buy_title_actionbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:cacheColorHint="@android:color/transparent"
android:divider="@drawable/reader_item_divider"
android:listSelector="@android:color/transparent" >
</ListView>
</RelativeLayout>
vending_list.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="@dimen/selectVmListCell_Height"
android:orientation="vertical" >
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="@dimen/selectVmListCell_Height"
android:layout_gravity="center_vertical"
android:background="@drawable/bg_listview"
android:gravity="center_vertical"
android:paddingLeft="@dimen/layout_Margin_10" >
<LinearLayout
android:id="@+id/imageTypeLayout"
android:layout_width="@dimen/smallImage_HW_45"
android:layout_height="fill_parent"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:gravity="center_vertical"
android:orientation="vertical" >
<ImageView
android:id="@+id/vendingImage"
style="@style/smallImageStyle"
android:src="@drawable/buy_main_not_shop" />
<TextView
android:id="@+id/distanceText"
style="@style/smallTxtStyle"
android:layout_gravity="center_horizontal"
android:gravity="center"
android:singleLine="true"
android:textColor="@color/lightOrangeColor" />
</LinearLayout>
<RelativeLayout
android:id="@+id/vendingSave"
android:layout_width="47.0dip"
android:layout_height="fill_parent"
android:layout_alignParentRight="true"
android:layout_centerVertical="true" >
<ImageView
android:id="@+id/vendingSaveImage"
android:layout_width="27.0dip"
android:layout_height="27.0dip"
android:layout_centerInParent="true"
android:layout_centerVertical="true"
android:background="@drawable/bg_favor_btn" />
</RelativeLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_centerVertical="true"
android:layout_marginLeft="@dimen/layout_Margin_10"
android:layout_toLeftOf="@id/vendingSave"
android:layout_toRightOf="@id/imageTypeLayout"
android:gravity="center_vertical"
android:orientation="vertical" >
<TextView
android:id="@+id/vending_name"
style="@style/midDarkGrayTxtStyle"
android:layout_width="fill_parent" />
<TextView
android:id="@+id/vending_address"
style="@style/smallLightGrayTxtStyle"
android:layout_width="fill_parent"
android:maxLines="2" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
style="@style/smallLightGrayTxtStyle"
android:text="Number：" />
<TextView
android:id="@+id/vending_id"
style="@style/smallLightGrayTxtStyle" />
</LinearLayout>
</LinearLayout>
</RelativeLayout>
</LinearLayout>
希望它可以帮助您找到如何将listview放入片段中。 我的listview中的元素很复杂，如果你只想要一行，它比我编码的更简单。
答案 1 :(得分：0)
尝试使用ListFragment，或者您可以关注vogella的this指南