我有自定义列表视图和活动。我从listview自定义调用事件imageclick并调用活动。但是adapter.notifyDataSetChanged（）;不工作。
package com.olsvn.studyapp;
import java.util.ArrayList;
import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import com.olsvn.studyapp.HomeActivity;
import com.olsvn.studyapp.dao.Word;
public class WordArrayAdapter extends ArrayAdapter<Word> implements
OnClickListener {
Activity context = null;
ArrayList<Word> myArray = null;
int layoutId;
public WordArrayAdapter(Activity context, int layoutId, ArrayList<Word> arr) {
super(context, layoutId, arr);
this.context = context;
this.layoutId = layoutId;
this.myArray = arr;
}
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
convertView = inflater.inflate(layoutId, null);
if (myArray.size() > 0 && position >= 0) {
final Word words = myArray.get(position);
final TextView txtcontent = (TextView) convertView
.findViewById(R.id.txtcontent);
final TextView txtspell1 = (TextView) convertView
.findViewById(R.id.txtspell1);
final TextView txtmeaning = (TextView) convertView
.findViewById(R.id.txtmeaning);
txtcontent.setText(words.getContent());
txtspell1.setText(words.getSpell1());
txtmeaning.setText(words.getMeaning());
final ImageView imgcheck = (ImageView) convertView
.findViewById(R.id.imgcheck);
if (words.getStatus() == 0) {
imgcheck.setImageResource(R.drawable.start);
} else if (words.getStatus() == 1) {
imgcheck.setImageResource(R.drawable.start_50);
} else {
imgcheck.setImageResource(R.drawable.start_100);
}
imgcheck.setOnClickListener(new OnItemClickListener(position));
}
return convertView;
}
private class OnItemClickListener implements OnClickListener {
private int mPosition;
OnItemClickListener(int position) {
mPosition = position;
}
@Override
public void onClick(View arg0) {
Word word_item = (Word) myArray.get(mPosition);
int item_id = word_item.getId();
int item_status = word_item.getStatus();
HomeActivity sct = new HomeActivity();
sct.setContext(context);
sct.CheckStatus(item_status, item_id,mPosition);
}
}
@Override
public Word getItem(int position) {
return super.getItem(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return super.getCount();
}
public WordArrayAdapter get(int mPosition) {
return null;
}
@Override
public void onClick(View arg0) {
}
}
和活动
package com.olsvn.studyapp;
import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListView;
import android.widget.Toast;
import com.olsvn.studyapp.dao.DatabaseHandler;
import com.olsvn.studyapp.dao.Word;
public class HomeActivity extends Activity {
Activity context;
ArrayList<Word> arrWords = new ArrayList<Word>();
WordArrayAdapter adapter;
ListView lvWords;
boolean CheckUpdate = false;
DatabaseHandler db;
public void setContext(Activity context) {
this.context = context;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
getTopRecord();
lvWords.setOnScrollListener(new OnScrollListener() {
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
if(firstVisibleItem+visibleItemCount == totalItemCount && totalItemCount!=0)
{
boolean flag_loading = false;
if(flag_loading == false)
{
flag_loading = true;
}
}
}
});
}
public void CheckStatus(int status, int id,int position) {
db = new DatabaseHandler(context);
int statusNew = status + 1;
if (status != 2) {
CheckUpdate = db.updateStatus(id, statusNew);
adapter.notifyDataSetChanged();
}
if (CheckUpdate = true) {
Toast.makeText(context, "update trạng thái thành công",
Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(context, "update trạng thái không thành công",
Toast.LENGTH_SHORT).show();
}
}
//get list word
public void getTopRecord() {
String where ="<2";
db = new DatabaseHandler(getApplicationContext());
arrWords = db.getByStatus(20, where);
lvWords = (ListView) findViewById(R.id.lvWords);
adapter = new WordArrayAdapter(this, R.layout.layout_tu_vung, arrWords);
lvWords.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
为什么adapter.notifyDataSetChanged（）;在CheckStatus（）中;不要调用myadapter而不是重新加载
列出错误（如果我编辑为......）
CheckUpdate = db.updateStatus(id, statusNew);
arrWords.get(position).setStatus(statusNew);
adapter.notifyDataSetChanged();
02-28 13：26：54.788：E / AndroidRuntime（9355）：致命异常：主要 02-28 13：26：54.788：E / AndroidRuntime（9355）：java.lang.IndexOutOfBoundsException：索引3无效，大小为0 02-28 13：26：54.788：E / AndroidRuntime（9355）：at java.util.ArrayList.throwIndexOutOfBoundsException（ArrayList.java:251） 02-28 13：26：54.788：E / AndroidRuntime（9355）：at java.util.ArrayList.get（ArrayList.java:304） 02-28 13：26：54.788：E / AndroidRuntime（9355）：at com.olsvn.studyapp.HomeActivity.CheckStatus（HomeActivity.java:41） 02-28 13：26：54.788：E / AndroidRuntime（9355）：at com.olsvn.studyapp.WordArrayAdapter $ OnItemClickListener.onClick（WordArrayAdapter.java:81） 02-28 13：26：54.788：E / AndroidRuntime（9355）：在android.view.View.performClick（View.java:4114） 02-28 13：26：54.788：E / AndroidRuntime（9355）：在android.view.View $ PerformClick.run（View.java:17097） 02-28 13：26：54.788：E / AndroidRuntime（9355）：在android.os.Handler.handleCallback（Handler.java:615）
答案 0 :(得分：0)
更改为：
public void CheckStatus(int status, int id,int position) {
db = new DatabaseHandler(context);
int statusNew = status + 1;
if (status != 2) {
CheckUpdate = db.updateStatus(id, statusNew);
arrWords.get(position).setStatus(statusNew);
adapter.notifyDataSetChanged();
}
if (CheckUpdate = true) {
Toast.makeText(context, "update trạng thái thành công",
Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(context, "update trạng thái không thành công",
Toast.LENGTH_SHORT).show();
}
}
您还需要更改列表中单词的状态