Reputation: 348
I have custom arrayadapter for displaying items for listview. I have two textview and one checkbox in item_list.xml file. I want to delete checked items from listview. But problem is when checked multiple items then not properly deleted from position. Below is my source code.
public class MainActivity extends Activity {
ListView listView;
Button btnDelete;
ArrayList<String> items = new ArrayList<String>();
ArrayList<String> ids = new ArrayList<String>();
CustomAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
btnDelete = (Button) findViewById(R.id.btnDelete);
for (int i = 0; i < 20; i++) {
items.add("Chk " + i);
}
adapter = new CustomAdapter(MainActivity.this, R.layout.custome_list,
items);
listView.setAdapter(adapter);
btnDelete.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if (ids.size() > 0) {
for (int i = 0; i < ids.size(); i++) {
items.remove(ids.get(i));
// items.remove(items.get(adapter.getItemViewType(ids.get(i))));
// items.remove(adapter.getItemViewType(ids.get(i)));
}
adapter.notifyDataSetChanged();
}
}
});
}
public class CustomAdapter extends ArrayAdapter<String> {
List<String> items;
int resource;
public CustomAdapter(Context context, int resource, List<String> items) {
super(context, resource, items);
this.items = items;
this.resource = resource;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final int pos = position;
ViewHolder holder = null;
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater inflater = getLayoutInflater();
convertView = inflater.inflate(resource, null);
holder.chk = (CheckBox) convertView.findViewById(R.id.chk);
holder.txt = (TextView) convertView.findViewById(R.id.txt);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.txt.setText(items.get(position));
// you have to reload the check states
holder.chk.setOnCheckedChangeListener(null);
holder.chk.setChecked(ids.contains(items.get(position)));
holder.chk
.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
if (isChecked) {
ids.add(items.get(position));
System.out.println("IDS A: " + ids.toString());
} else {
if (ids.contains(items.get(position))) {
//int i = ids.indexOf(position);
ids.remove(items.get(position));
System.out.println("IDS R: "
+ ids.toString());
}
}
}
});
return convertView;
}
}
public class ViewHolder {
CheckBox chk;
TextView txt;
}
}
Upvotes: 3
Views: 4211
Reputation: 478
Remove by position is not a good work around. You should try removing by the object instead.
Here is the sample code
public class MainActivity extends Activity {
ListView listView;
Button btnDelete;
ArrayList<String> items = new ArrayList<String>();
ArrayList<String> ids = new ArrayList<String>();
CustomAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
btnDelete = (Button) findViewById(R.id.btnDelete);
for (int i = 0; i < 20; i++) {
items.add("Chk " + i);
}
adapter = new CustomAdapter(MainActivity.this, R.layout.custome_list,
items);
listView.setAdapter(adapter);
btnDelete.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if (ids.size() > 0) {
for (int i = 0; i < ids.size(); i++) {
items.remove(ids.get(i));
// items.remove(items.get(adapter.getItemViewType(ids.get(i))));
// items.remove(adapter.getItemViewType(ids.get(i)));
}
adapter.notifyDataSetChanged();
}
}
});
}
public class CustomAdapter extends ArrayAdapter<String> {
List<String> items;
int resource;
public CustomAdapter(Context context, int resource, List<String> items) {
super(context, resource, items);
this.items = items;
this.resource = resource;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final int pos = position;
ViewHolder holder = null;
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater inflater = getLayoutInflater();
convertView = inflater.inflate(resource, null);
holder.chk = (CheckBox) convertView.findViewById(R.id.chk);
holder.txt = (TextView) convertView.findViewById(R.id.txt);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.txt.setText(items.get(position));
// you have to reload the check states
holder.chk.setOnCheckedChangeListener(null);
holder.chk.setChecked(ids.contains(position));
holder.chk
.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView,
boolean isChecked) {
if (isChecked) {
ids.add(items.get(position));
System.out.println("IDS A: " + ids.toString());
} else {
if (ids.contains(items.get(position))) {
//int i = ids.indexOf(position);
ids.remove(items.get(position));
System.out.println("IDS R: "
+ ids.toString());
}
}
}
});
return convertView;
}
}
public class ViewHolder {
CheckBox chk;
TextView txt;
}
}
Edit
If you are getting outofbound exeption on deletion you can try using this loop instead
for (String item : ids) {
items.remove(item);
}
Upvotes: 4
Reputation: 2077
I think relying to remove items based on index can be a bit complicated, instead it is better you rely on removing items itself. I have made some modifications to your class. Not sure if it would meet your requirement.
public class MainActivity extends Activity {
ListView listView;
Button btnDelete;
ArrayList<String> items = new ArrayList<String>();
ArrayList<String> selectedItems = new ArrayList<String>();
CustomAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.listView1);
btnDelete = (Button) findViewById(R.id.btnDelete);
for (int i = 0; i < 20; i++) {
items.add("Chk " + i);
}
adapter = new CustomAdapter(MainActivity.this, R.layout.custome_list, items);
listView.setAdapter(adapter);
btnDelete.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if (selectedItems.size() > 0) {
for (int i = 0; i < selectedItems.size(); i++) {
boolean isremoved = items.remove(selectedItems.get(i));
// items.remove(items.get(adapter.getItemViewType(ids.get(i))));
// items.remove(adapter.getItemViewType(ids.get(i)));
System.out.println();
}
//selectedItems.clear();
((CustomAdapter) listView.getAdapter()).notifyDataSetChanged();
}
}
});
}
public class CustomAdapter extends ArrayAdapter<String> {
List<String> items;
int resource;
public CustomAdapter(Context context, int resource, List<String> items) {
super(context, resource, items);
this.items = items;
this.resource = resource;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final int pos = position;
ViewHolder holder = null;
if (convertView == null) {
holder = new ViewHolder();
LayoutInflater inflater = getLayoutInflater();
convertView = inflater.inflate(resource, null);
holder.chk = (CheckBox) convertView.findViewById(R.id.checkBox1);
holder.txt = (TextView) convertView.findViewById(R.id.textView1);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.txt.setText(items.get(position));
// you have to reload the check states
holder.chk.setOnCheckedChangeListener(null);
holder.chk.setChecked(selectedItems.contains(items.get(position)));
holder.chk.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
selectedItems.add(items.get(position));
System.out.println("IDS A: " + selectedItems.toString());
} else {
if (selectedItems.contains(items.get(position))) {
int i = selectedItems.indexOf(items.get(position));
selectedItems.remove(i);
System.out.println("IDS R: " + selectedItems.toString());
}
}
}
});
return convertView;
}
}
public class ViewHolder {
CheckBox chk;
TextView txt;
}
}
Hope it helps.
Upvotes: 1