我有一个listview，其值为两个edittext。第一个sqlite数据库保存这些edittextand的值，然后在listviews中转换它。我想要的是当用户点击列表项时，它将使用数据库查询显示下一个活动中该项的值。谁能告诉我怎么能这样做呢。请详细回答我，因为我是android的新手
答案 0 :(得分：0)
在项目上单击获取项目的行ID。 使用行id获取特定行
来调用查询String selection = KEYID + " = ? ";
String[] selectionArgs = new String[]{rowId};
Cursor cursor = database.query(TABLENAME, null, selection, selectionArgs, null, null, null);
if (cursor != null) {
while (cursor.moveToNext()) {
//PARSE AND RETURN DATA
}
}
答案 1 :(得分：0)
**Check this full code MainActivity**
package com.example.developer.database;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.text.InputType;
import android.util.Patterns;
import android.view.View;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import com.example.developer.database.helper.DBhelper;
import com.example.developer.database.model.Contact;
import com.example.developer.database.model.MyListAdapter;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
DBhelper dBhelper;
private Button SUBMIT;
SQLiteDatabase sqldb;
TextView infotext;
private Button edit;
private String[] arrText =
new String[]{"First Name","useremail", "password"
,"city","phone no"};
private String[]arrcity=new String[]{"INDIA","PAKISTAN","CHINA"};
// private String[] arrTemp;
ArrayList<Contact> arrlst = new ArrayList<>();
private MyListAdapter myListAdapter;
private String adap1="adap1";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
edit=(Button)findViewById(R.id.next);
infotext=(TextView) findViewById(R.id.infotext);
edit.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i=new Intent(MainActivity.this,Show.class);
startActivity(i);
}
});
dBhelper=new DBhelper(this);
//arrTemp = new String[arrText.length];
for (int i = 0; i < arrText.length; i++) {
Contact reg =new Contact();
reg.setFieldName(arrText[i]);
// reg.setValue("");
switch (i){
case 5:
reg.setInput_type(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
break;
case 6:
reg.setInput_type(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
break;
}
arrlst.add(reg);
}
myListAdapter = new MyListAdapter(MainActivity.this,arrlst,adap1);
ListView listView = (ListView) findViewById(R.id.listViewMain);
listView.setAdapter(myListAdapter);
setupViews();
}
public void setupViews() {
SUBMIT = (Button) findViewById(R.id.submit);
SUBMIT.setOnClickListener(MainActivity.this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.submit) {
String NAME=arrlst.get(0).getValue();
String Email=arrlst.get(1).getValue();
String Password=arrlst.get(2).getValue();
String City=AppData.city;
String PhoneNo=arrlst.get(4).getValue();
arrlst.get(0).setError("");
arrlst.get(1).setError("");
arrlst.get(2).setError("");
arrlst.get(3).setError("");
arrlst.get(4).setError("");
if(NAME.length()<1) {
// alert();
arrlst.get(0).setError("Not a valid Name");
myListAdapter.notifyDataSetChanged();
}
else if(NAME.length()<1)
{
alert();
}
else if(Password.length()<1){
alert();
}
else if (City.isEmpty()){
alert();
}
else if(!isValidEmail(Email) ){
// Toast.makeText(getBaseContext(), "please give proper email", Toast.LENGTH_SHORT).show();
arrlst.get(1).setError("Not a valid email");
myListAdapter.notifyDataSetChanged();
}
else {
dBhelper.inserRecord(NAME,Email,Password,City,PhoneNo,AppData.city_pos);
Toast.makeText(MainActivity.this, "inserted.", Toast.LENGTH_LONG).show();
Intent i=new Intent(MainActivity.this,Show.class);
startActivity(i);
}
}
}
public void alert(){
AlertDialog.Builder adb=new AlertDialog.Builder(MainActivity.this);
adb.setTitle("UnSucessful");
adb.setMessage("You're not Successfully Registered!");
adb.setPositiveButton("OK",new DialogInterface.OnClickListener(){
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
AlertDialog AD=adb.create();
AD.show();
}
private boolean isValidEmail(String EMAIL) {
return Patterns.EMAIL_ADDRESS.matcher(EMAIL).matches();
}
}
**Adapter for MainActivity**
package com.example.developer.database.adapter;
import android.app.Activity;
import android.content.Context;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import com.example.developer.database.AppData;
import com.example.developer.database.MainActivity;
import com.example.developer.database.R;
import com.example.developer.database.helper.DBhelper;
import com.example.developer.database.model.Contact;
import java.util.ArrayList;
/**
* Created by sanjeev on 31/3/17.
*/
public class MyListAdapter extends BaseAdapter {
Context context;
ArrayList<Contact> arrlst;
LayoutInflater inflater;
ArrayList<String> citylist=new ArrayList<>();
String dec = "";
String adap1 = "";
String ada2 = "";
private Contact contact ;
public MyListAdapter(Activity activity, ArrayList<Contact> arrlst,Contact contact,String ada2) {
this.context = activity;
this.arrlst = arrlst;
inflater = activity.getLayoutInflater();
this.contact = contact;
this.ada2 = ada2;
dec = ada2;
citylist.add("Kolkata");
citylist.add("burdwan");
citylist.add("bankura");citylist.add("mednipur");citylist.add("birbhum");
citylist.add("malda");
citylist.add("Coachbihar");
}
public MyListAdapter(MainActivity mainActivity, ArrayList<Contact> arrlst, String adap1) {
this.context = mainActivity;
this.arrlst = arrlst;
inflater = mainActivity.getLayoutInflater();
this.adap1 = adap1;
dec = adap1;
citylist.add("Kolkata");
citylist.add("burdwan");
citylist.add("bankura");citylist.add("mednipur");citylist.add("birbhum");
citylist.add("malda");
citylist.add("Coachbihar");
}
@Override
public int getCount() {
Log.d("ppp",""+arrlst.size());
return arrlst.size();
}
@Override
public Object getItem(int position) {
return arrlst.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
private class ViewHolder {
TextView textView1;
EditText editText1;
public Spinner spinner;
public ViewHolder(View item) {
editText1 = (EditText) item.findViewById(R.id.editText1);
}
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final int pos = position;
final ViewHolder holder;
if (pos == 3) {
convertView = inflater.inflate(R.layout.spinner, null, false);
} else {
convertView = inflater.inflate(R.layout.layout, null, false);
}
holder = new ViewHolder(convertView);
convertView.setTag(holder);
if(pos==3){
holder.spinner = (Spinner) convertView.findViewById(R.id.sp);
holder.textView1 = (TextView) convertView.findViewById(R.id.textView1);
}
else{
holder.textView1 = (TextView) convertView.findViewById(R.id.textView1);
holder.editText1 = (EditText) convertView.findViewById(R.id.editText1);
holder.textView1.setText(arrlst.get(pos).getFieldName());
}
if (pos == 3) {
holder.textView1.setText(arrlst.get(3).getFieldName());
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>
(context, android.R.layout.simple_spinner_item,citylist);
dataAdapter.setDropDownViewResource
(android.R.layout.simple_spinner_dropdown_item);
holder.spinner.setAdapter(dataAdapter);
if(contact!=null) {
holder.spinner.setSelection(contact.getCITYPOSITION());
}
holder.spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
AppData.city = holder.spinner.getSelectedItem().toString();
AppData.city_pos= holder.spinner.getSelectedItemPosition();
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}else{
holder.editText1.setTag(pos);
holder.editText1.setHint(arrlst.get(pos).getFieldName());
holder.editText1.setText(arrlst.get(pos).getValue());
holder.editText1.setInputType(arrlst.get(pos).getInput_type());
}
if (pos == 3) {
}else {
if(!arrlst.get(pos).getError().equalsIgnoreCase("")){
holder.editText1.setError(arrlst.get(pos).getError());
holder.editText1.requestFocus();
}
holder.editText1.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
Log.d("POS", "" + pos + " VAL" + editable.toString());
int pos = (int) holder.editText1.getTag();
arrlst.get(pos).setValue(editable.toString());
}
});
}
return convertView;
}
}
**Database code**
package com.example.developer.database.helper;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import com.example.developer.database.model.Contact;
import java.util.ArrayList;
public class DBhelper extends SQLiteOpenHelper {
private static String CREATE_TABLE1;
// Database name
static String DATABASE_NAME = "EmployeeRecords";
// Talble name
public static final String TABLE1_NAME = "employee";
// Fields for table
public static final String ID = "id";
public static final String NAME = "name";
public static final String EMAIL = "email";
public static final String PASSWORD = "password";
public static final String CITY = "city";
public static final String PHONE = "phone";
public static final String CITYPOS= "city_pos";
// Required resorces to manage database
private ContentValues cValues;
private SQLiteDatabase dataBase = null;
private Cursor cursor;
public DBhelper(Context context) {
super(context, context.getExternalFilesDir(null).getAbsolutePath()
+ "/" + DATABASE_NAME, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
CREATE_TABLE1 = "CREATE TABLE " + TABLE1_NAME +"("
+ ID+" INTEGER PRIMARY KEY AUTOINCREMENT, "
+ NAME + " TEXT NOT NULL, "
+ EMAIL + " TEXT NOT NULL, "
+ PASSWORD + " TEXT NOT NULL, "+ CITY + " TEXT NOT NULL, "+ PHONE + " TEXT NOT NULL, "+ CITYPOS + " INTEGER) ";
db.execSQL(CREATE_TABLE1);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE1_NAME);
onCreate(db);
}
public void inserRecord(String name, String email , String password , String city, String phone, int city_pos) {
dataBase = getWritableDatabase();
cValues = new ContentValues();
cValues.put(NAME, name);
cValues.put(EMAIL, email);
cValues.put(PASSWORD, password);
cValues.put(CITY, city);
cValues.put(PHONE, phone);
cValues.put(CITYPOS, city_pos);
// insert data into database
dataBase.insert(TABLE1_NAME, null, cValues);
dataBase.close();
}
public void updateRecord(String name, String email ,String password , String city , String phone,int city_pos) {
dataBase = getWritableDatabase();
cValues = new ContentValues();
if(name!=null) {
cValues.put(NAME, name);
}
if(email!=null) {
cValues.put(EMAIL, email);
} if(password!=null) {
cValues.put(PASSWORD, password);
} if(city!=null) {
cValues.put(CITY, city);
} if(phone!=null) {
cValues.put(PHONE, phone);
}
cValues.put(CITYPOS, city_pos);
// Update data from database table
dataBase.update(DBhelper.TABLE1_NAME, cValues,
null, null);
dataBase.close();
}
public ArrayList<Contact> getValues() {
ArrayList<Contact> values = new ArrayList<Contact>();
String selectQuery = "SELECT * FROM " + TABLE1_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if(cursor.moveToFirst()) {
do {
Contact contact = new Contact();
contact.setID(cursor.getString(0));
contact.setNAME(cursor.getString(1));
contact.setEMAIL(cursor.getString(2));
contact.setPASSWORD(cursor.getString(3));
contact.setCITY(cursor.getString(4));
contact.setPHONE(cursor.getString(5));
contact.setCITYPOSITION(cursor.getInt(6));
Log.d("jjj","ghh"+cursor);
// Adding contact to list
values.add(contact);
//
// values.add(cursor.getString(cursor.getColumnInde"value")));
}while(cursor.moveToNext());
}
cursor.close();
db.close();
return values;
}
public void deleteUser(String id)
{
SQLiteDatabase db = this.getWritableDatabase();
try
{
db.delete(TABLE1_NAME, "ID = ?", new String[] { id });
}
catch(Exception e)
{
e.printStackTrace();
}
finally
{
db.close();
}
}
public Contact getContact(String id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE1_NAME, new String[] { ID,
NAME, EMAIL, PASSWORD, CITY, PHONE, CITYPOS}, ID + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Contact contact = new Contact(cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5), cursor.getInt(6));
Log.d("aaa","ggg"+contact);
// return contact
return contact;
}
}
**ShowListActivityAdapter code here**
package com.example.developer.database.adapter;
import com.example.developer.database.model.Contact;
import java.util.ArrayList;
public class UserAdapter extends BaseAdapter {
ArrayList<Contact> arrayList;
Activity activity;
LayoutInflater infl;
public UserAdapter(Activity activity, ArrayList<Contact> arrayList) {
//getting values from MainActivity
infl = activity.getLayoutInflater();
this.arrayList = arrayList;
this.activity = activity;
}
@Override
public int getCount() {
Log.d("aaa", "" + arrayList.size());
return arrayList.size();
}
@Override
public Object getItem(int position) {
return arrayList.get(position);
}
@Override
public long getItemId(int position) {
return 0;
}
static class ViewHolder {
TextView name;
TextView email;
TextView password;
TextView city;
TextView phone;
public ViewHolder(View item) {
//we have to find the id of listview to avoid viewlost
name= (TextView)item.findViewById(R.id.name);
email=(TextView)item.findViewById(R.id.email);
password=(TextView)item.findViewById(R.id.password);
city=(TextView)item.findViewById(R.id.city);
phone=(TextView)item.findViewById(R.id.phone);
}
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final int pos = position;
View view = convertView;
final ViewHolder holder ;
// view will be null for the first time only
if (view == null) {
view = infl.inflate(R.layout.layout1, parent, false);
holder = new ViewHolder(view);
view.setTag(holder);
} else {
holder = (ViewHolder) view.getTag();
}
holder.name.setText(arrayList.get(pos).getNAME());
holder.email.setText(arrayList.get(pos).getEMAIL());
holder.password.setText(arrayList.get(pos).getPASSWORD());
holder.city.setText(arrayList.get(pos).getCITY());
holder.phone.setText(arrayList.get(pos).getPHONE());
return view;
}
}
package com.example.developer.database.model;
/**
* Created by sanjeev on 31/3/17.
*/
public class Contact {
String fieldName, value;
int input_type = -1;
String city;
String error = "";
String NAME,EMAIL,PASSWORD,CITY,PHONE,ID;
int CITYPOSITION;
public Contact(String string, String string1, String string2, String string3, String string4, int pos) {
this.NAME = string;
this.EMAIL = string1;
this.PASSWORD = string2;
this.CITY = string3;
this.PHONE = string4;
this.CITYPOSITION = pos;
}
public Contact() {
}
public String getFieldName() {
return fieldName;
}
public void setFieldName(String fieldName) {
this.fieldName = fieldName;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
public int getInput_type() {
return input_type;
}
public void setInput_type(int input_type) {
this.input_type = input_type;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getID() {
return ID;
}
public void setID(String ID) {
this.ID = ID;
}
public String getNAME() {
return NAME;
}
public void setNAME(String NAME) {
this.NAME = NAME;
}
public String getEMAIL() {
return EMAIL;
}
public void setEMAIL(String EMAIL) {
this.EMAIL = EMAIL;
}
public String getPASSWORD() {
return PASSWORD;
}
public void setPASSWORD(String PASSWORD) {
this.PASSWORD = PASSWORD;
}
public String getCITY() {
return CITY;
}
public void setCITY(String CITY) {
this.CITY = CITY;
}
public String getPHONE() {
return PHONE;
}
public void setPHONE(String PHONE) {
this.PHONE = PHONE;
}
public int getCITYPOSITION() {
return CITYPOSITION;
}
public void setCITYPOSITION(int CITYPOSITION) {
this.CITYPOSITION = CITYPOSITION;
}
public String getError() {
return error;
}
public void setError(String error) {
this.error = error;
}
}