您好，在我的应用程序中，我正在解析json url并显示图像和文本现在我要添加按钮。如果我点击按钮，我想转移到另一个活动。现在我的问题是，如果我点击按钮没有发生任何事情。可以任何人请帮助我。
ListViewAdapter类：
public class ListViewAdapter extends BaseAdapter {
// Declare Variables
Context context;
LayoutInflater inflater;
ArrayList<HashMap<String, String>> data;
ImageLoader imageLoader;
HashMap<String, String> resultp = new HashMap<String, String>();
public ListViewAdapter(Context context,
ArrayList<HashMap<String, String>> arraylist) {
this.context = context;
data = arraylist;
imageLoader = new ImageLoader(context);
}
@Override
public int getCount() {
return data.size();
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
public View getView(final int position, View convertView, ViewGroup parent) {
// Declare Variables
TextView title;
ImageView thumb_url;
inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View itemView = inflater.inflate(R.layout.listview_item, parent, false);
// Get the position
resultp = data.get(position);
// Locate the TextViews in listview_item.xml
title = (TextView) itemView.findViewById(R.id.rank);
// Locate the ImageView in listview_item.xml
thumb_url = (ImageView) itemView.findViewById(R.id.flag);
// Capture position and set results to the TextViews
title.setText(resultp.get(MainActivity.TITLE));
// Capture position and set results to the ImageView
// Passes flag images URL into ImageLoader.class
imageLoader.DisplayImage(resultp.get(MainActivity.THUMB_URL), thumb_url);
// Capture ListView item click
Button Add = (Button) itemView.findViewById(R.id.add);
Add.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// Get the position
resultp = data.get(position);
Intent intent = new Intent(context, SingleItemView.class);
// Pass all data rank
intent.putExtra("title", resultp.get(MainActivity.TITLE));
// Pass all data country
/*intent.putExtra("country", resultp.get(MainActivity.COUNTRY));
// Pass all data population
intent.putExtra("population",resultp.get(MainActivity.POPULATION));
*/// Pass all data flag
intent.putExtra("thumb_url", resultp.get(MainActivity.THUMB_URL));
// Start SingleItemView Class
context.startActivity(intent);
Intent in = new Intent(getApplicationContext(), MainActivity.class);
startActivity(in);
}
private void startActivity(Intent in) {
// TODO Auto-generated method stub
}
private Context getApplicationContext() {
// TODO Auto-generated method stub
return context;
}
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
});
return itemView;
}
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
}
}
listview_item.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" >
<ImageView
android:id="@+id/flag"
android:layout_width="80dp"
android:layout_height="80dp"
android:layout_centerVertical="true"
android:layout_margin="5dp"
android:background="#444"
android:padding="3dp" />
<TextView
android:id="@+id/rank"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dip"
android:layout_toRightOf="@+id/flag"
android:maxLines="1"
android:textSize="15dip"
android:textStyle="bold" />
<!-- <TextView
android:id="@+id/ranklabel"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
<TextView
android:id="@+id/rank"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
-->
<!-- <ImageView
android:id="@+id/flag"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:background="#000000"
android:layout_toRightOf="@+id/flag"
android:padding="1dp" />
-->
<Button
android:id="@+id/add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="@+id/rank"
android:text="Add" />
</RelativeLayout>
MainActivity类：
public class MainActivity extends Activity {
// Declare Variables
JSONObject jsonobject;
JSONArray jsonarray;
ListView listview;
ListViewAdapter adapter;
ProgressDialog mProgressDialog;
ArrayList<HashMap<String, String>> arraylist;
static String TITLE = "title";
/*static String COUNTRY = "country";
static String POPULATION = "population";*/
static String THUMB_URL = "thumb_url";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the view from listview_main.xml
setContentView(R.layout.listview_main);
// Execute DownloadJSON AsyncTask
new DownloadJSON().execute();
}
// DownloadJSON AsyncTask
private class DownloadJSON extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Create a progressdialog
mProgressDialog = new ProgressDialog(MainActivity.this);
// Set progressdialog title
mProgressDialog.setTitle("Loading...");
// Set progressdialog message
mProgressDialog.setMessage("Loading...");
mProgressDialog.setIndeterminate(false);
// Show progressdialog
mProgressDialog.show();
}
@Override
protected Void doInBackground(Void... params) {
// Create an array
arraylist = new ArrayList<HashMap<String, String>>();
// Retrieve JSON Objects from the given URL address
jsonobject = JSONfunction
.getJSONfromURL("http://indianpoliticalleadersmap.com/android/DemoSchool/json/json_item.php");
try {
// Locate the array name in JSON
jsonarray = jsonobject.getJSONArray("veg_food");
for (int i = 0; i < jsonarray.length(); i++) {
HashMap<String, String> map = new HashMap<String, String>();
jsonobject = jsonarray.getJSONObject(i);
// Retrive JSON Objects
map.put("title", jsonobject.getString("title"));
/*map.put("country", jsonobject.getString("country"));
map.put("population", jsonobject.getString("population"));*/
map.put("thumb_url", jsonobject.getString("thumb_url"));
// Set the JSON Objects into the array
arraylist.add(map);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void args) {
// Locate the listview in listview_main.xml
listview = (ListView) findViewById(R.id.listview);
// Pass the results into ListViewAdapter.java
adapter = new ListViewAdapter(MainActivity.this, arraylist);
// Set the adapter to the ListView
listview.setAdapter(adapter);
// Close the progressdialog
mProgressDialog.dismiss();
}
}
}
答案 0 :(得分：0)
将hashMap存储在视图标记中。
Button Add = (Button) itemView.findViewById(R.id.add);
Add.setTag(resultp);
然后在onClick（）中访问它，就像这样
而不是尝试通过可能不引用当前视图的位置访问它，而是通过其标记访问它。在您的代码中，替换
行resultp = data.get(position);
与
resultp = (HashMap<String, String>) view.getTag();
编辑：添加resultp = data.get(position);后，如上所示
用以下
@Override
public void onClick(View arg0) {
resultp = (HashMap<String, String>) view.getTag();
Intent intent = new Intent(context, SingleItemView.class);
intent.putExtra("title", resultp.get(MainActivity.TITLE));
intent.putExtra("population",resultp.get(MainActivity.POPULATION));
intent.putExtra("thumb_url", resultp.get(MainActivity.THUMB_URL));
context.startActivity(intent);
}