Android 如何从适配器类调用AsyncTask？

我有一个带有

GetMembersAsyncTask

的活动类。我还有一个适配器类，带有

deleteAncySctask

。当我在列表视图项中单击“取消图像”时，

deleteSynchctask

将调用。如果成功删除该项，则我将调用

deleteAnctTask

中的

OnPostExecute（）

方法

public class AddmemberSearch extends Activity {
private ListViewAdapter listviewAdapter;
protected void onCreate(Bundle savedInstanceState)
 {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.family_search_members);
    ButterKnife.inject(this);
    new GetFamilyListAsynctask().execute();
 }
class GetMembersAsyncTask extends AsyncTask<String, String, String> {
    protected void OnPreExecute(){}
    protected String doInBackground(String... params) { 
        some code here
    }
    protected void onPostExecute(String file_url) { }
}
}

---

这里介绍如何从适配器类调用

GetMemberAsynctask

？

您可以将适配器类移动到活动类中，并将适配器类设置为内部类。因此，您有权在适配器中调用GetMemberAsynctask，如下所示：

public class AddmemberSearch extends Activity {
private ListViewAdapter listviewAdapter;
protected void onCreate(Bundle savedInstanceState)
 {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.family_search_members);
    ButterKnife.inject(this);
    new GetFamilyListAsynctask().execute();
 }

public class ListViewAdapter extends BaseAdapter {
Activity context;    
private ImageButton cancel_img;
SharedPreferences sharedPrefUser;
public ListViewAdapter(Activity context, ArrayList<familiesListBO> data) {
    super();
    this.context = context;
    this.data = data;
}
@Override
public int getCount() {
    return data.size();
}
@Override
public Object getItem(int position) {
    return position;
}
@Override
public long getItemId(int position) {
    return position;
}
private class ViewHolder {
    TextView txtViewMember; 
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    final ViewHolder holder;
    LayoutInflater inflater = context.getLayoutInflater();
    FamiliesListBO familiesListBO;
    familiesListBO = data.get(position);
    if (convertView == null) {
        convertView = inflater.inflate(R.layout.added_member_listview, null);
        holder = new ViewHolder();
        holder.txtViewMember = (TextView) convertView.findViewById(R.id.txt_addedmember_names);            
        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }        
    if (familiesListBO.getName() != null) {
        holder.txtViewMember.setText(familiesListBO.getName());
        familiesListBO.getName();
    }
    cancel_img = (ImageButton) convertView.findViewById(R.id.cancel_row_img);
    cancel_img.setTag(holder);
    cancel_img.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            new DeleteAsynccTask().execute();
        }
    });
    return convertView;
}

class DeleteAsynccTask extends AsyncTask<String, String, String> {
    ResultVO getDeletionsResponse;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }
    @Override
    protected String doInBackground(String... params) {
         try {                
            getDeletionsResponse = services.delete("this is delete code");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
    @Override
    protected void onPostExecute(String s) {
        int appStatusCode = getDeletionsResponse.getAppStatusCode();
        if (appStatusCode == Constants.APP_STATUS_CODE_SUCCESS) {
            ExceptionMessages.showAlertDialog(context, IFamilyUtil.FAMILY_DELETE_SUCCESS_TITLE, IFamilyUtil.FAMILY_DELETE_SUCCESS_MESSAGE, true);
            new AddmemberSearch.GetMembersAsyncTask().execute();
        } else {
            ExceptionMessages.showAlertDialog(context, IFamilyUtil.FAMILY_DELETE_FAIL_TITLE, IFamilyUtil.FAMILY_DELETE_FAIL_MESSAGE, true);
        }
        notifyDataSetChanged();           
    }
}

class GetMembersAsyncTask extends AsyncTask<String, String, String> {
    protected void OnPreExecute(){}
    protected String doInBackground(String... params) { 
        some code here
    }
    protected void onPostExecute(String file_url) { }
}

public类AddmemberSearch扩展活动{
私有ListViewAdapter ListViewAdapter；
创建时受保护的void（Bundle savedInstanceState）
{
super.onCreate（savedInstanceState）；
setContentView（R.layout.family\u search\u成员）；
注射（这个）；
新建GetFamilyListSyncTask（）.execute（）；
}
公共类ListViewAdapter扩展了BaseAdapter{
活动语境；
私人图像按钮取消\u img；
SharedReferences SharedReferuser；
公共ListViewAdapter（活动上下文、ArrayList数据）{
超级（）；
this.context=上下文；
这个数据=数据；
}
@凌驾
public int getCount（）{
返回data.size（）；
}
@凌驾
公共对象getItem（int位置）{
返回位置；
}
@凌驾
公共长getItemId（int位置）{
返回位置；
}
私有类视窗持有者{
TextView txtViewMember；
}
@凌驾
公共视图getView（最终整数位置、视图转换视图、视图组父视图）{
最终持票人；
LayoutInflater充气器=上下文。getLayoutInflater（）；
FamiliesListBO FamiliesListBO；
familiesListBO=data.get（位置）；
if（convertView==null）{
convertView=充气机。充气（R.layout.added\u member\u listview，null）；
holder=新的ViewHolder（）；
holder.txtViewMember=（TextView）convertView.findViewById（R.id.txt_addedmember_name）；
convertView.setTag（支架）；
}否则{
holder=（ViewHolder）convertView.getTag（）；
}        
if（familiesListBO.getName（）！=null）{
holder.txtViewMember.setText（familiesListBO.getName（））；
familiesListBO.getName（）；
}
cancel\u img=（ImageButton）convertView.findViewById（R.id.cancel\u row\u img）；
取消图像设置标签（支架）；
取消\u img.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图arg0）{
新建DeleteAsynccTask（）.execute（）；
}
});
返回视图；
}
类DeleteAsynccTask扩展了AsyncTask{
结果获得删除响应；
@凌驾
受保护的void onPreExecute（）{
super.onPreExecute（）；
}
@凌驾
受保护的字符串doInBackground（字符串…参数）{
试试{
getDeletionsResponse=services.delete（“这是删除代码”）；
}捕获（例外e）{
e、 printStackTrace（）；
}
返回null；
}
@凌驾
受保护的void onPostExecute（字符串s）{
int-appStatusCode=getDeletionsResponse.getAppStatusCode（）；
if（appStatusCode==常量。应用程序状态代码成功）{
ExceptionMessages.showAlertDialog（上下文，IFamilyUtil.FAMILY\u DELETE\u SUCCESS\u标题，IFamilyUtil.FAMILY\u DELETE\u SUCCESS\u消息，true）；
新建AddmemberSearch.GetMembersAsyncTask（）.execute（）；
}否则{
ExceptionMessages.showAlertDialog（上下文，IFamilyUtil.FAMILY\u DELETE\u FAIL\u标题，IFamilyUtil.FAMILY\u DELETE\u FAIL\u消息，true）；
}
notifyDataSetChanged（）；
}
}
类GetMembersAsyncTask扩展异步任务{
受保护的void OnPreExecute（）{}
受保护的字符串doInBackground（字符串…参数）{
这里有一些代码
}
受保护的void onPostExecute（字符串文件\u url）{}
}

---

我希望有帮助！

只需将ListViewAdapter放在AddMemberSearch类中

从AddMemberSearch类中删除GetMembersAsyncTask内部类
和
将GetMembersAsyncTask作为seprate类（将其放入包中）

---

之后，您可以像这样从任何地方调用“new GetFamilyListSyncTask（）.execute（）；”。

您可以将适配器类移动到活动类中，并将适配器类设置为内部类。因此您可以在适配器中调用GetMemberAsynctask。这种方法是gud。。。

public class AddmemberSearch extends Activity {
private ListViewAdapter listviewAdapter;
protected void onCreate(Bundle savedInstanceState)
 {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.family_search_members);
    ButterKnife.inject(this);
    new GetFamilyListAsynctask().execute();
 }

public class ListViewAdapter extends BaseAdapter {
Activity context;    
private ImageButton cancel_img;
SharedPreferences sharedPrefUser;
public ListViewAdapter(Activity context, ArrayList<familiesListBO> data) {
    super();
    this.context = context;
    this.data = data;
}
@Override
public int getCount() {
    return data.size();
}
@Override
public Object getItem(int position) {
    return position;
}
@Override
public long getItemId(int position) {
    return position;
}
private class ViewHolder {
    TextView txtViewMember; 
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
    final ViewHolder holder;
    LayoutInflater inflater = context.getLayoutInflater();
    FamiliesListBO familiesListBO;
    familiesListBO = data.get(position);
    if (convertView == null) {
        convertView = inflater.inflate(R.layout.added_member_listview, null);
        holder = new ViewHolder();
        holder.txtViewMember = (TextView) convertView.findViewById(R.id.txt_addedmember_names);            
        convertView.setTag(holder);
    } else {
        holder = (ViewHolder) convertView.getTag();
    }        
    if (familiesListBO.getName() != null) {
        holder.txtViewMember.setText(familiesListBO.getName());
        familiesListBO.getName();
    }
    cancel_img = (ImageButton) convertView.findViewById(R.id.cancel_row_img);
    cancel_img.setTag(holder);
    cancel_img.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            new DeleteAsynccTask().execute();
        }
    });
    return convertView;
}

class DeleteAsynccTask extends AsyncTask<String, String, String> {
    ResultVO getDeletionsResponse;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }
    @Override
    protected String doInBackground(String... params) {
         try {                
            getDeletionsResponse = services.delete("this is delete code");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
    @Override
    protected void onPostExecute(String s) {
        int appStatusCode = getDeletionsResponse.getAppStatusCode();
        if (appStatusCode == Constants.APP_STATUS_CODE_SUCCESS) {
            ExceptionMessages.showAlertDialog(context, IFamilyUtil.FAMILY_DELETE_SUCCESS_TITLE, IFamilyUtil.FAMILY_DELETE_SUCCESS_MESSAGE, true);
            new AddmemberSearch.GetMembersAsyncTask().execute();
        } else {
            ExceptionMessages.showAlertDialog(context, IFamilyUtil.FAMILY_DELETE_FAIL_TITLE, IFamilyUtil.FAMILY_DELETE_FAIL_MESSAGE, true);
        }
        notifyDataSetChanged();           
    }
}

class GetMembersAsyncTask extends AsyncTask<String, String, String> {
    protected void OnPreExecute(){}
    protected String doInBackground(String... params) { 
        some code here
    }
    protected void onPostExecute(String file_url) { }
}