删除Android中的ListView项
有人能给我一个删除所有ListView项目并替换为新项目的示例代码吗 我尝试更换适配器项目,但没有成功。我的代码是删除Android中的ListView项,android,android-listview,Android,Android Listview,有人能给我一个删除所有ListView项目并替换为新项目的示例代码吗 我尝试更换适配器项目,但没有成功。我的代码是 populateList(){ results //populated arraylist with strings ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, re
populateList(){
results //populated arraylist with strings
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, results);
listview.setAdapter(adapter);
adapter.notifyDataSetChanged();
listview.setOnItemClickListener(this);
}
// now populating list again
repopulateList(){
results1 //populated arraylist with strings
ArrayAdapter<String> adapter1 = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, results1);
listview.setAdapter(adapter1);
adapter1.notifyDataSetChanged();
listview.setOnItemClickListener(this);
}
populateList(){
结果//用字符串填充arraylist
ArrayAdapter=新的ArrayAdapter(此,
android.R.layout.simple_list_item_1,results);
setAdapter(适配器);
adapter.notifyDataSetChanged();
setOnItemClickListener(this);
}
//现在再次填充列表
重新流行者(){
结果1//用字符串填充arraylist
ArrayAdapter适配器1=新的ArrayAdapter(此,
android.R.layout.simple_list_item_1,results1);
setAdapter(适配器1);
adapter1.notifyDataSetChanged();
setOnItemClickListener(this);
}
这里repopulateList()
方法将添加到ListView项,但它不会删除/替换所有ListView项。您可以使用
adapter.clear()
这将删除第一个适配器的所有项,然后您可以设置另一个适配器,或者重用该适配器并将这些项添加到旧适配器中。如果你使用
adapter.add()
要将数据添加到列表中,您不需要调用notifyDataSetChanged,我认为如果您添加以下代码,它将起作用
listview.invalidateViews();
要删除一个项,只需从传递给适配器的arraylist中删除该项,然后执行listview.invalidateViews()代码>
这将刷新listviewnames=db.getSites();
names = db.getSites();
la = new ArrayAdapter<String>(EditSiteList.this,
android.R.layout.simple_list_item_1, names);
EditSiteList.this.setListAdapter(la);
listview.invalidateViews();
la=新阵列适配器(EditSiteList.this,
android.R.layout.simple_list_item_1,name);
EditSiteList.this.setListAdapter(la);
listview.invalidateViews();
这段代码对我来说很好。您将希望从适配器对象中删除()
该项,然后只需在适配器上运行notifyDatasetChanged()
,任何ListView
都将(应该)自行循环和更新
下面是一个带有AlertDialog
s的简短活动示例:
adapter = new MyListAdapter(this);
lv = (ListView) findViewById(android.R.id.list);
lv.setAdapter(adapter);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
AlertDialog.Builder adb=new AlertDialog.Builder(MyActivity.this);
adb.setTitle("Delete?");
adb.setMessage("Are you sure you want to delete " + position);
final int positionToRemove = position;
adb.setNegativeButton("Cancel", null);
adb.setPositiveButton("Ok", new AlertDialog.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
MyDataObject.remove(positionToRemove);
adapter.notifyDataSetChanged();
}});
adb.show();
}
});
adapter=新的MyListAdapter(此);
lv=(ListView)findViewById(android.R.id.list);
低压设置适配器(适配器);
lv.setOnItemClickListener(新的OnItemClickListener(){
公共视图单击(适配器视图a、视图v、内部位置、长id){
AlertDialog.Builder adb=新建AlertDialog.Builder(MyActivity.this);
adb.setTitle(“删除?”);
adb.setMessage(“您确定要删除”+位置);
最终int位置ToRemove=位置;
adb.setNegativeButton(“取消”,空);
adb.setPositiveButton(“确定”,新建AlertDialog.OnClickListener(){
public void onClick(DialogInterface dialog,int which){
MyDataObject.remove(位置删除);
adapter.notifyDataSetChanged();
}});
adb.show();
}
});
将其从适配器中卸下,然后通知阵列适配器数据集已更改
m_adapter.remove(o);
m_adapter.notifyDataSetChanged();
int count=adapter.getCount();
for(int i=0;i
然后调用notifyDataSetChanged()代码>
- 您应该只使用一个与需要列出的数据列表绑定的适配器
- 当需要删除和替换所有项时,必须使用“list.clear()”清除数据列表中的所有项,然后使用“list.addAll(list)”添加新数据
这里有一个例子:
List<String> myList = new ArrayList<String>();
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, myList);
listview.setAdapter(adapter);
listview.setOnItemClickListener(this);
populateList(){
List<String> result = getDataMethods();
myList.addAll(result);
adapter.notifyDataSetChanged();
}
repopulateList(){
List<String> result = getDataMethods();
myList.clear();
myList.addAll(result);
adapter.notifyDataSetChanged();
}
List myList=new ArrayList();
ArrayAdapter=新的ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,myList);
setAdapter(适配器);
setOnItemClickListener(this);
大众主义者(){
列表结果=getDataMethods();
myList.addAll(结果);
adapter.notifyDataSetChanged();
}
重新流行者(){
列表结果=getDataMethods();
myList.clear();
myList.addAll(结果);
adapter.notifyDataSetChanged();
}
首先,您应该从列表中删除该项目。稍后,您可以清空适配器并用新列表重新填充
private void add(final List<Track> trackList) {
MyAdapter bindingData = new MyAdapter(MyActivity.this, trackList);
list = (ListView) findViewById(R.id.my_list); // TODO
list.setAdapter(bindingData);
// Click event for single list row
list.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
final int position, long id) {
// ShowPlacePref(places, position);
AlertDialog.Builder showPlace = new AlertDialog.Builder(
Favoriler.this);
showPlace.setMessage("Remove from list?");
showPlace.setPositiveButton("DELETE", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
trackList.remove(position); //FIRST OF ALL REMOVE ITEM FROM LIST
list.setAdapter(null); // THEN EMPTY YOUR ADAPTER
add(trackList); // AT LAST REFILL YOUR LISTVIEW (Recursively)
}
});
showPlace.setNegativeButton("CANCEL", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
}
});
showPlace.show();
}
});
}
private void add(最终列表跟踪列表){
MyAdapter bindingData=新的MyAdapter(MyActivity.this,trackList);
list=(ListView)findViewById(R.id.my_list);//TODO
list.setAdapter(bindingData);
//单击单个列表行的事件
list.setOnItemClickListener(新的OnItemClickListener(){
public void onItemClick(AdapterView父级、视图、,
最终整数位置,长id){
//ShowPlacePref(地点、位置);
AlertDialog.Builder showPlace=新建AlertDialog.Builder(
福利勒,这件事);
setMessage(“从列表中删除?”);
setPositiveButton(“删除”,新的OnClickListener(){
public void onClick(DialogInterface dialog,int其中){
trackList.remove(position);//首先从列表中删除项
list.setAdapter(null);//然后清空适配器
add(trackList);//最后重新填充LISTVIEW(递归)
}
});
setNegativeButton(“取消”,新的OnClickListener(){
public void onClick(DialogInterface dialog,int which){
}
});
showPlace.show();
}
});
}
很简单。首先你应该清除你的收藏,然后像下面的代码一样清除列表:
yourCollection.clear();
setListAdapter(null);
试试这个代码,它适合我
public class Third extends ListActivity {
private ArrayAdapter<String> adapter;
private List<String> liste;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_third);
String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
"Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
"Linux", "OS/2" };
liste = new ArrayList<String>();
Collections.addAll(liste, values);
adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, liste);
setListAdapter(adapter);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
liste.remove(position);
adapter.notifyDataSetChanged();
}
}
public类活动{
专用阵列适配器;
私有列表列表;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_第三);
字符串[]值=新字符串[]{“Android”、“iPhone”、“WindowsMobile”,
“黑莓”、“WebOS”、“Ubuntu”、“Windows7”、“Max OS X”,
“Linux”、“OS/2”};
liste=newarraylist();
Collections.addAll(列表、值);
适配器=新阵列适配器(此,
android.R.布局。
public class Third extends ListActivity {
private ArrayAdapter<String> adapter;
private List<String> liste;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_third);
String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
"Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
"Linux", "OS/2" };
liste = new ArrayList<String>();
Collections.addAll(liste, values);
adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, liste);
setListAdapter(adapter);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
liste.remove(position);
adapter.notifyDataSetChanged();
}
}
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int
position, long id) {
// it will get the position of selected item from the ListView
final int selected_item = position;
new AlertDialog.Builder(MainActivity.this).
setIcon(android.R.drawable.ic_delete)
.setTitle("Are you sure...")
.setMessage("Do you want to delete the selected item..?")
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which)
{
list.remove(selected_item);
arrayAdapter.notifyDataSetChanged();
}
})
.setNegativeButton("No" , null).show();
return true;
}
});