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删除Android中的ListView项_Android_Android Listview - Fatal编程技术网

删除Android中的ListView项

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

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, 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()
这将刷新listview

names=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()

  • 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;
        }
    });