我有一个listview，它是从sqlite数据库中获取的数据填充的。对于每个列表项我膨胀以下布局
<?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" >
<CheckBox
android:id="@+id/delete_or_not"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<LinearLayout
android:layout_width="0dip"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_weight="1.0" >
<TextView
android:id="@+id/date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Chat_Date"
android:textSize="10dp"
/>
<TextView
android:id="@+id/summaryofchat"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Chat_Summary"
android:textSize="20dp" />
</LinearLayout>
目前iam扩展了baseadapter。但是pblm是复选框正在被回收，所以当我删除一些项目并调用notifydataset（）时，一些复选框被选中，而我没有这样做。 对于列表视图我有一个页脚，其中有一个删除按钮...所以在用户滚动列表视图并选择要删除的列表项（通过单击复选框）后，我需要将它们删除在数据库中我想要listview显示新数据....我该怎么做.....我不需要代码但告诉我我可以实现它的方式....
我发布了我的自定义baseadapter的代码
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import com.Raja.BlueTooth.DataBaseRelated.BlueToothDataBaseHelper;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.provider.ContactsContract.Contacts.Data;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class ListofSavedChatsAdapter extends BaseAdapter {
private Context mContext;
SQLiteDatabase dbinstance;
private String[] dates;
private String[] chats;
private ArrayList<Boolean> mChecked;
BlueToothDataBaseHelper retriever;
ListView lv1;
View footer;
Cursor c;
private ListofSavedChatsAdapter adapterInstance;
public ListofSavedChatsAdapter(Context context, ListView lv, View v)
{
this.lv1 = lv;
this.mContext = context;
retrieveFromDataBase();
this.footer = v;
}
public void retrieveFromDataBase() {
retriever = new BlueToothDataBaseHelper(mContext);
dbinstance = retriever.getReadableDatabase();
c = dbinstance.query(BlueToothDataBaseHelper.CHAT_TABLE, new String[] {
BlueToothDataBaseHelper.CHAT_TABLE_ID_COLUMN,
BlueToothDataBaseHelper.CHAT_TABLE_DATE_COLUMN,
BlueToothDataBaseHelper.CHAT_TABLE_DATA_COLUMN }, null, null,
null, null, null);
Log.d("count :", String.valueOf(c.getCount()));
mChecked = new ArrayList<Boolean>();
for (int i1 = 0; i1 < c.getCount(); i1++) {
mChecked.add(i1, false);
Log.d("RetrieveFromDataBase:item at " + String.valueOf(i1),
"is set" + String.valueOf(mChecked.get(i1)));
}
dates = new String[c.getCount()];
chats = new String[c.getCount()];
c.moveToFirst();
int i = 0;
while (!c.isAfterLast()) {
dates[i] = c.getString(c.getColumnIndex(BlueToothDataBaseHelper.CHAT_TABLE_DATE_COLUMN));
chats[i] = c.getString(c.getColumnIndex(BlueToothDataBaseHelper.CHAT_TABLE_DATA_COLUMN));
Log.d("date:", dates[i]);
Log.d("chat:", chats[i]);
c.moveToNext();
i++;
}
c.close();
}
public class ViewHolder
{
TextView DATE;
TextView DATA;
CheckBox check;
}
public void itemsSelected()
{
for(int j=0;j<mChecked.size();j++)
{
if(mChecked.get(j))
{
Log.d("ItemSelected:item at " +String.valueOf(j) , "is checked");
//String ssss = """ + chats[j]+""";
Boolean dora = dbinstance.delete(BlueToothDataBaseHelper.CHAT_TABLE, BlueToothDataBaseHelper.CHAT_TABLE_DATA_COLUMN + " = '"+chats[j]+"'", null) > 0;
Log.d("Delete", String.valueOf(dora));
}
}
}
public void delete()
{
dbinstance = retriever.getWritableDatabase();
itemsSelected();
dbinstance.close();
retrieveFromDataBase();
notifyDataSetChanged();
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return dates.length;
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
Log.d("position", String.valueOf(position));
Log.d("items in cursor", String.valueOf(c.getCount()));
if(convertView == null)
{
ViewHolder mViewHolder1 = new ViewHolder();
LayoutInflater mLayoutInflater = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = mLayoutInflater.inflate(R.layout.savedchatselementlayout, null);
mViewHolder1.DATA = (TextView)convertView.findViewById(R.id.summaryofchat);
mViewHolder1.DATE = (TextView)convertView.findViewById(R.id.date);
mViewHolder1.check = (CheckBox)convertView.findViewById(R.id.delete_or_not);
MyCheckedListener kk = new MyCheckedListener(position);
mViewHolder1.check.setOnCheckedChangeListener(kk);
mChecked.set(position, kk.getCheckedorNot());
mViewHolder1.check.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
LayoutInflater mLayoutInflater1 = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// LinearLayout temp = (LinearLayout)mLayoutInflater1.inflate(R.layout.listofsavedchats, null).findViewById(R.id.buttonbar);
if(buttonView.isChecked())
{
Log.d("came to checked loop", "why");
Log.w("MCHECKED_LENGTH_A", ""+mChecked.size());
Log.w("MCHECKED_POSITION_A", ""+position);
Log.w("ADAPTER_LENGTH_A", ""+getCount());
mChecked.set(position, true);
Log.d("Checkedloop:item at "+position, String.valueOf(mChecked.get(position)));
//lv1.addFooterView(footer);
//temp.setVisibility(View.VISIBLE);
// (mLayoutInflater1.inflate(R.layout.listofsavedchats, null)).findViewById(R.id.buttonbar).setVisibility(View.VISIBLE);
Toast.makeText(mContext, "checkbox at "+position + "is checked" , Toast.LENGTH_SHORT).show();
}
else
{
Log.d("position in else loop is:", String.valueOf(position));
Log.d("came to checked else loop", "why");
Log.w("MCHECKED_LENGTH_B", ""+mChecked.size());
Log.w("MCHECKED_POSITION_B", ""+position);
Log.w("ADAPTER_LENGTH_A", ""+getCount());
mChecked.set(position, false);
Log.d("UnCheckedloop:item at "+position, String.valueOf(mChecked.get(position)));
//lv1.removeFooterView(footer);
// temp.setVisibility(View.GONE);
//mLayoutInflater1.inflate(R.layout.listofsavedchats, null).findViewById(R.id.buttonbar).setVisibility(View.INVISIBLE);
Toast.makeText(mContext, "checkbox at "+position + "is unchecked" , Toast.LENGTH_SHORT).show();
}
}
});
convertView.setTag(mViewHolder1);
}
ViewHolder mViewHolder2 = (ViewHolder)convertView.getTag();
mViewHolder2.DATA.setText(chats[position]);
mViewHolder2.DATE.setText(dates[position]);
Log.d("mChecked["+String.valueOf(position)+"]", String.valueOf(mChecked.get(position)));
Log.d("i accessed:", String.valueOf(mChecked.get(position)));
//Log.d("mChecked", mChecked.)
Log.d("checkbox at "+String.valueOf(position)+" is:", String.valueOf(mViewHolder2.check.isChecked()));
mViewHolder2.check.setChecked(false);
return convertView;
}
}
D/create string is :( 234): create table Chat_Table( _id integer primary key, Date DATETIME not null, Data Text not null, Checked Integer);
D/count : ( 234): 6
D/RetrieveFromDataBase:item at 0( 234): is setfalse
D/RetrieveFromDataBase:item at 1( 234): is setfalse
D/RetrieveFromDataBase:item at 2( 234): is setfalse
D/RetrieveFromDataBase:item at 3( 234): is setfalse
D/RetrieveFromDataBase:item at 4( 234): is setfalse
D/RetrieveFromDataBase:item at 5( 234): is setfalse
D/date: ( 234): 2012-3-31 2:0
D/chat: ( 234): Ravi
D/date: ( 234): 2012-3-31 3:1
D/chat: ( 234): chittor
D/date: ( 234): 2012-3-31 23:23
D/chat: ( 234): idiot
D/date: ( 234): 2012-3-31 23:23
D/chat: ( 234): rascal
D/date: ( 234): 2012-3-31 23:23
D/chat: ( 234): bloody
D/date: ( 234): 2012-3-31 23:23
D/chat: ( 234): donkey
D/position( 234): 0
D/items in cursor( 234): 6
D/mChecked[0]( 234): false
D/i accessed:( 234): false
D/checkbox at 0 is:( 234): true
D/position in else loop is:( 234): 7
D/came to checked else loop( 234): why
W/MCHECKED_LENGTH_B( 234): 6
W/MCHECKED_POSITION_B( 234): 7
W/ADAPTER_LENGTH_A( 234): 6
D/AndroidRuntime( 234): Shutting down VM
W/dalvikvm( 234): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
E/AndroidRuntime( 234): Uncaught handler: thread main exiting due to uncaught exception
E/AndroidRuntime( 234): java.lang.IndexOutOfBoundsException
E/AndroidRuntime( 234): at java.util.ArrayList.set(ArrayList.java:580)
E/AndroidRuntime( 234): at com.Raja.BlueTooth.UI.ListofSavedChatsAdapter$1.onCheckedChanged(ListofSavedChatsAdapter.java:185)
E/AndroidRuntime( 234): at android.widget.CompoundButton.setChecked(CompoundButton.java:122)
E/AndroidRuntime( 234): at com.Raja.BlueTooth.UI.ListofSavedChatsAdapter.getView(ListofSavedChatsAdapter.java:205)
E/AndroidRuntime( 234):