我使用适配器填充列表视图，并使用方法“GetItemId”从所点击项目的数据库中获取_ID。
但是，该值未进入详细信息活动（显示listview上单击项目的详细信息），我在此错误中搜索了很多内容，我无法修复它。
我没有错误，但详细信息活动为空，因为它没有获取id / incocrrect id来获取数据。
我的适配器：
public class RegistosCursorAdapter extends CursorAdapter {
public RegistosCursorAdapter (Context context, Cursor cursor, int flags) {
super(context, cursor, 0);
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
// The newView method is used to inflate a new view and return it,
// you don't bind any data to the view at this point.
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
return LayoutInflater.from(context).inflate(R.layout.registos_layout, parent, false);
}
// The bindView method is used to bind all data to a given view
// such as setting the text on a TextView.
@Override
public void bindView(View view, Context context, Cursor cursor) {
// Find fields to populate in inflated template
TextView um = (TextView) view.findViewById(R.id.um);
TextView dois = (TextView) view.findViewById(R.id.dois);
// Extract properties from cursor
String body = cursor.getString(cursor.getColumnIndexOrThrow("Sintoma"));
String priority = cursor.getString(cursor.getColumnIndexOrThrow("Dinicio"));
// Populate fields with extracted properties
um.setText(body);
dois.setText(String.valueOf(priority));
}
}
包含listview的活动
public class TabSintomas extends Fragment {
private DAL dal;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
final RelativeLayout rootView = (RelativeLayout) inflater.inflate(R.layout.fragment_tab_sintomas, container, false);
dal = new DAL(getActivity());
dal.connect(DBAccessMode.READ);
// Vai usar um cursor para percorrer a base de dados, usando o metodo "selectALLFromRegSintomas()" que vem da classe "DAL".
Cursor cursor = dal.selectALLFromRegSintomas();
// é precisar declarar o layout do fragment com que estamos a trabalhar
final View v = inflater.inflate(R.layout.fragment_tab_sintomas, container, false);
// Declarar a listview onde vao aparecer os dados
ListView lv = (ListView) v.findViewById(R.id.listv);
// Declarar o adapter que define como aparecem os dados na listview
final RegistosCursorAdapter todoAdapter = new RegistosCursorAdapter(getActivity(), cursor, 0);
// Ligar o adapter
lv.setAdapter(todoAdapter);
// Nos fragments é preciso sempre fazer return do layout que queremos mostrar, neste caso (fragment_tab_sintomas);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
long idpos = todoAdapter.getItemId(position);// This is the _ID value
Intent intent = new Intent(getActivity(), DetalhesSintoma.class);
intent.putExtra("myExtras", idpos);
startActivity(intent);
//Toast.makeText(getActivity(),"clique",
// Toast.LENGTH_SHORT).show();
}
});
return v;
}
}
DetailsActivity（需要点击项目中的ID以显示该项目的详细信息）
public class DetalhesSintoma extends AppCompatActivity {
private DAL dal;
private TextView DataInicio;
private EditText HoraIncio;
private TextView DataFim;
private EditText HoraFim;
private TextView Intensidade;
private TextView Motivo;
private TextView Medicacao;
private Button Apagar;
private Button Concluido;
private long idpos;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_detalhes_sintoma);
DataInicio = (TextView) findViewById(R.id.DiaInicioText);
// HoraIncio = (EditText) findViewById(R.id.HoraInicioText);
DataFim = (TextView) findViewById(R.id.DiaFimText);
// HoraFim = () findViewById(R.id.HoraFimText);
Intensidade = (TextView) findViewById(R.id.IntensidadeText);
Motivo = (TextView) findViewById(R.id.MotivoText);
Medicacao = (TextView) findViewById(R.id.MedicacaoText);
Apagar = (Button) findViewById(R.id.btnApagar);
Concluido = (Button) findViewById(R.id.btnConcluido);
Intent intent = getIntent();
idpos = intent.getLongExtra("myExtras", 0);
dal = new DAL(this);
dal.connect(DBAccessMode.READ);
Cursor res = dal.selectFromRegSintomasWhereId(idpos);
res.moveToFirst();
StringBuilder datahora = new StringBuilder();
while (!res.isAfterLast()) {
Intensidade.setText(res.getString(res.getColumnIndex(DBContract.Reg_sintomas.COL_Intensidade)));
String Data = res.getString(res.getColumnIndex(DBContract.Reg_sintomas.COL_D_Inicio));
String Hora = res.getString(res.getColumnIndex(DBContract.Reg_sintomas.COL_H_Inicio));
res.moveToNext();
DataInicio.setText(datahora.append(Data + " ás " + Hora));
}
Cursor res1 = dal.selectFromRegSintomasWhereId(idpos);
res1.moveToFirst();
StringBuilder datahoraF = new StringBuilder();
while (!res1.isAfterLast()) {
String Data = res1.getString(res1.getColumnIndex(DBContract.Reg_sintomas.COL_D_Fim));
String Hora = res1.getString(res1.getColumnIndex(DBContract.Reg_sintomas.COL_H_Fim));
res1.moveToNext();
DataFim.setText(datahoraF.append(Data + " ás " + Hora));
}
Cursor res2 = dal.selectFromMotivoSintomassWhereId(idpos);
res2.moveToFirst();
StringBuilder sb = new StringBuilder();
while (!res2.isAfterLast()) {
sb.append(res2.getString(res2.getColumnIndex(DBContract.Motivo_sintomas.COL_Motivo)));
res2.moveToNext();
}
Motivo.setText(sb.toString());
Cursor res3 = dal.selectMedicacaoWhereId(idpos);
res3.moveToFirst();
StringBuilder sb2 = new StringBuilder();
while (!res3.isAfterLast()) {
sb2.append(res3.getString(res3.getColumnIndex(DBContract.Medicacao.COL_Medicacao)));
res3.moveToNext();
}
Medicacao.setText(sb2.toString());
Concluido.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(DetalhesSintoma.this, VerRegsSintomas.class);
startActivity(intent);
}
});
Apagar.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v) {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(DetalhesSintoma.this);
// Setting Dialog Title
alertDialog.setTitle("Apagar");
// Setting Dialog Message
alertDialog.setMessage("Tem a certeza que quer apagar este registo ? ");
// Setting Icon to Dialog
// Setting Positive "Yes" Button
alertDialog.setPositiveButton("Sim", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dal.deleteFromRegSintomasWhereId(idpos);
Intent intent = new Intent(DetalhesSintoma.this, VerRegsSintomas.class);
startActivity(intent);
Toast.makeText(getApplicationContext(), "Registo apagado !", Toast.LENGTH_SHORT).show();
}
});
// Setting Negative "NO" Button
alertDialog.setNegativeButton("Não", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Write your code here to invoke NO event
Toast.makeText(getApplicationContext(), "Acção cancelada", Toast.LENGTH_SHORT).show();
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
});
}
}
我尝试从列表视图获取ID的代码，上面的代码，为了您更轻松：
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
long idpos = todoAdapter.getItemId(position);// This is the _ID value
Intent intent = new Intent(getActivity(), DetalhesSintoma.class);
intent.putExtra("myExtras", idpos);
startActivity(intent);
//Toast.makeText(getActivity(),"clique",
// Toast.LENGTH_SHORT).show();
}
});
如果我设置idpos = 1，他会向我显示satabase上第一项的详细信息，所以我假设他没有通过antything
答案 0 :(得分：0)
1）来自here
的getItemAtPosition(position);
// ListView Item Click Listener
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// ListView Clicked item index
int itemPosition = position;
// ListView Clicked item value
String itemValue = (String) listView.getItemAtPosition(position);
// Show Alert
Toast.makeText(getApplicationContext(),
"Position :"+itemPosition+" ListItem : " +itemValue , Toast.LENGTH_LONG)
.show();
}
});
尝试使用：myListData.get(position).getId()其中myListData是制作列表的数组。
我想指出
getItemId()中ArrayAdapter()总是返回 -1与assert false : "TODO"; return -1;
来源：SO Question
检查getPosition()，getItem()和getItemId()
请参阅此处：android-reference