不能将列表视图的位置传递给第二个活动？
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【中文标题】不能将列表视图的位置传递给第二个活动？【英文标题】：Can't Pass the postion of a listview to second activity? 【发布时间】：2015-03-21 16:41:24 【问题描述】：您好，我创建了一个存储一些编辑文本的数据库。我有三个活动 A、B 和 C。活动 A 在列表视图中显示存储的值。当单击活动 A 中的列表视图项时，它会将其位置和存储的数据传递给活动 B，活动 B 将其显示为简单文本且无法编辑。现在我想将这些数据从活动 B 传递到可以编辑的活动 C。如何通过 Acitvity B 将列表视图位置从 A 传递到 C。
活动 A
public class UserActivity extends Activity implements OnItemClickListener
private ListAdapter users;
private ListView lista;
private AccessModel data;
private ArrayList<User> query;
private LinearLayout empty_data;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_ACTION_BAR);
setContentView(R.layout.listusers);
lista = (ListView) findViewById(R.id.lstusers);
empty_data= (LinearLayout) findViewById(R.id.empty_data);
data = new AccessModel(this);
@Override
protected void onResume()
// TODO Auto-generated method stub
super.onResume();
query = data.listUser();
if(query.size()>0)
empty_data.setVisibility(View.GONE);
else
empty_data.setVisibility(View.VISIBLE);
users = new ListAdapter(this, query);
lista.setAdapter(users);
lista.setOnItemClickListener(this);
@Override
public boolean onPrepareOptionsMenu(Menu menu)
// TODO Auto-generated method stub
getMenuInflater().inflate(R.menu.optionsbar, menu);
return super.onPrepareOptionsMenu(menu);
@Override
public boolean onOptionsItemSelected(MenuItem item)
// TODO Auto-generated method stub
switch (item.getItemId())
case R.id.adduser:
Intent i = new Intent(this, RegisterUser.class);
startActivity(i);
return true;
default:
return super.onOptionsItemSelected(item);
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3)
// TODO Auto-generated method stub
User u = (User) query.get(position);
Intent i = new Intent(UserActivity.this, ViewPatientData.class);
i.putExtra(getString(R.string.valuesId), String.valueOf(u.getId()));
startActivity(i);
活动 B
protected void onCreate(Bundle savedInstanceState)
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_ACTION_BAR);
setContentView(R.layout.view_patient_data);
getActionBar().setDisplayHomeAsUpEnabled(true);
data = new AccessModel(this);
name = (TextView) findViewById(R.id.tv_name);
age = (TextView) findViewById(R.id.tv_age);
gender = (TextView) findViewById(R.id.tv_gender);
height = (TextView) findViewById(R.id.tv_height);
weight = (TextView) findViewById(R.id.tv_weight);
dateofbirth = (TextView) findViewById(R.id.tv_dateofbirth);
religion = (TextView) findViewById(R.id.tv_religion);
maritalstatus = (TextView) findViewById(R.id.tv_maritalstatus);
dateofadmission = (TextView) findViewById(R.id.tv_dateofadmission);
address = (TextView) findViewById(R.id.tv_address);
contact = (TextView) findViewById(R.id.tv_contact);
emergencycontact = (TextView) findViewById(R.id.tv_emergencycontact);
email = (TextView) findViewById(R.id.tv_email);
occupation = (TextView) findViewById(R.id.tv_occupation);
bloodtype = (TextView) findViewById(R.id.tv_bloodtype);
refferedvia = (TextView) findViewById(R.id.tv_refferedvia);
btnedit = (Button) findViewById(R.id.btedit);
btnedit.setOnClickListener(this);
@Override
protected void onResume()
// TODO Auto-generated method stub
super.onResume();
Bundle v = getIntent().getExtras();
if(v==null)
back();
return;
userId = v.getString(getString(R.string.valuesId));
loadData(userId);
private void loadData(String id)
User u = (User) data.getUser(id);
Toast.makeText(this, u.getName(), Toast.LENGTH_LONG).show();
name.setText(u.getName().toString());
age.setText(u.getAge());
gender.setText(u.getGender());
height.setText(u.getHeight());
weight.setText(u.getWeight());
dateofbirth.setText(u.getDateofbirth());
religion.setText(u.getReligion());
maritalstatus.setText(u.getMaritalstatus());
dateofadmission.setText(u.getDateofadmission());
contact.setText(u.getContact());
emergencycontact.setText(u.getEmergencycontact());
email.setText(u.getEmail());
occupation.setText(u.getOccupation());
bloodtype.setText(u.getBloodtype());
refferedvia.setText(u.getRefferedvia());
address.setText(u.getAddress());
@Override
public void onClick(View v)
// TODO Auto-generated method stub
switch(v.getId())
case R.id.btedit:
@Override
public boolean onOptionsItemSelected(MenuItem item)
// TODO Auto-generated method stub
switch (item.getItemId())
case android.R.id.home:
back();
return true;
default:
return super.onOptionsItemSelected(item);
private void back()
Intent i = new Intent(this, UserActivity.class);
startActivity(i);
活动 C
@Override
protected void onResume()
// TODO Auto-generated method stub
super.onResume();
Bundle v = getIntent().getExtras();
if(v==null)
back();
return;
userId = v.getString(getString(R.string.valuesId));
loadData(userId);
private void loadData(String id)
User u = (User) data.getUser(id);
Toast.makeText(this, u.getName(), Toast.LENGTH_LONG).show();
name.setText(u.getName().toString());
age.setText(u.getAge());
gender.setText(u.getGender());
height.setText(u.getHeight());
weight.setText(u.getWeight());
dateofbirth.setText(u.getDateofbirth());
religion.setText(u.getReligion());
maritalstatus.setText(u.getMaritalstatus());
dateofadmission.setText(u.getDateofadmission());
contact.setText(u.getContact());
emergencycontact.setText(u.getEmergencycontact());
email.setText(u.getEmail());
occupation.setText(u.getOccupation());
bloodtype.setText(u.getBloodtype());
refferedvia.setText(u.getRefferedvia());
address.setText(u.getAddress());
private void updateUser(String id)
String[] ids = id;
try
data.updateUser(ids,name.getText().toString(), age.getText().toString(), gender.getText().toString(), height.getText().toString(), weight.getText().toString(), dateofbirth.getText().toString()
,religion.getText().toString(), maritalstatus.getText().toString(), dateofadmission.getText().toString(), address.getText().toString(), contact.getText().toString(), emergencycontact.getText().toString()
,email.getText().toString(), occupation.getText().toString(), bloodtype.getText().toString(), refferedvia.getText().toString());
Toast.makeText(this, getString(R.string.good), Toast.LENGTH_LONG).show();
catch(Exception e)
Toast.makeText(this, getString(R.string.error), Toast.LENGTH_LONG).show();
private void deleteUser(String id)
String[] ids = id;
try
data.deleteUser(ids);
Toast.makeText(this, getString(R.string.good), Toast.LENGTH_LONG).show();
back();
catch(Exception e)
Toast.makeText(this, getString(R.string.error), Toast.LENGTH_LONG).show();
@Override
public void onClick(View v)
// TODO Auto-generated method stub
switch(v.getId())
case R.id.btupdate:
updateUser(userId);
break;
case R.id.btdelete:
deleteUser(userId);
break;
@Override
public boolean onOptionsItemSelected(MenuItem item)
// TODO Auto-generated method stub
switch (item.getItemId())
case android.R.id.home:
back();
return true;
default:
return super.onOptionsItemSelected(item);
private void back()
Intent i = new Intent(this, UserActivity.class);
startActivity(i);
【问题讨论】：
【参考方案1】：你已经得到了答案。它与您在 Activity B 中添加到 Intent 的 id extra 非常相似。
在 A 中，执行以下操作：
Intent i = new Intent(ActivityA.this, ActivityB.class);
i.putExtra(getString(R.string.valuesId), String.valueOf(u.getId()));
i.putExtra("position", position);
在 B 中，将其提取为：
Bundle extras = getIntent().getExtras();
int position = extras.getInt("position");
Intent i = new Intent(ActivityB.this, ActivityC.class);
i.putExtra(getString(R.string.valuesId), String.valueOf(u.getId()));
i.putExtra("position", position);
在C中，像以前一样提取位置：
Bundle extras = getIntent().getExtras();
int position = extras.getInt("position");
【讨论】：
为什么？这是 Android 希望您在活动之间传递数据的方式 请看上面的编辑代码，告诉我把你提供的这些代码放在哪里 这些行就在您执行 startActivity(i) 之前。所以在 A 中，它将位于 onItemClick() 方法中。在 B 和 C 中，它将在 back() 方法中。只需添加我编写的代码行，而你还没有，你应该很高兴。 对我不起作用..仍然给出错误...在活动 BI 中必须将此代码放在案例 R.id.btedit 之后：我认为在活动 C 中 back() 方法不正确在我看来这个地方......可能是它在简历活动中？？？？【参考方案2】：您必须从变量中的 Activity B 中的意图包中检索值，然后将该值传递到进入活动 C 的新意图包中
【讨论】：
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