如何在Longpress上更新和删除ListView中的数据

Question

I have some records in list view, I want to update and delete these records when I long press on particular item of list. Like this structure DBHelper1 DBHelper2 DBHelper3 DBHelper4 DBHelper5 DBHelper6

package com.example.loginproject.model; public class Record {

String lead;
String name;
String mobile;
public Record(String lead, String name, String mobile) {
    this.lead = lead;
    this.name = name;
    this.mobile = mobile;
}
public String getLead() {
    return lead;
}
public Record(){}
public void setLead(String lead) {
    this.lead = lead;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getMobile() {
    return mobile;
}
public void setMobile(String mobile) {
    this.mobile = mobile;

}}

public class MyAdapter extends BaseAdapter {

Context context;
ArrayList<Record> arrayList;

public  MyAdapter(Context context,ArrayList<Record>arrayList){

    this.context=context;
    this.arrayList=arrayList;
}

@Override
public int getCount() {
    return this.arrayList.size();
}

@Override
public Object getItem(int position) {
    return arrayList.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater layoutInflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView= layoutInflater.inflate(R.layout.custom_list_view,null);
        TextView textView1 =(TextView)convertView.findViewById(R.id.textview_leads);
        TextView textView2 =(TextView)convertView.findViewById(R.id.textview_names);
        TextView textView3 =(TextView)convertView.findViewById(R.id.textview_company);


        Record record=arrayList.get(position);
        textView1.setText(record.getLead());
        textView2.setText(record.getName());
        textView3.setText(record.getMobile());

    return convertView;
}

}

public class Home extends AppCompatActivity {

TextView Name;
Button refresh,addlead;
DatabaseHelper databaseHelper;
SQLiteOpenHelper sqLiteOpenHelper;
SQLiteDatabase db;
ListView listView;
MyAdapter myAdapter;
ArrayList<Record>arrayList;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);
    Name=(TextView)findViewById(R.id.Name);
    addlead=(Button)findViewById(R.id.addlead);
    refresh=(Button)findViewById(R.id.viewlead);
    listView=(ListView)findViewById(R.id.list_view);
    sqLiteOpenHelper=new DatabaseHelper(this);
    db=sqLiteOpenHelper.getReadableDatabase();
    databaseHelper=new DatabaseHelper(this);
    arrayList=new ArrayList<>();
    loaddatainlist();
    registerForContextMenu(listView);

    Name.setText(getIntent().getStringExtra(MainActivity.user));
    refresh();
   add_lead();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu, menu);
    return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    if (id == R.id.mybutton) {
        AlertDialog.Builder builder=new AlertDialog.Builder(this);
        builder.setMessage("Are you really want to Logout ?")
                .setCancelable(false)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        Toast.makeText(getApplicationContext(),"Logout Successfully",Toast.LENGTH_SHORT).show();
                        finish();
                        //startActivity(new Intent(Home.this,MainActivity.class));
                    }
                })
                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                    }
                });
        AlertDialog alertDialog=builder.create();
        alertDialog.show();

    }
    return super.onOptionsItemSelected(item);
}


public void add_lead()
{
    addlead.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
         startActivity(new Intent(Home.this,Registration.class));
        }
    });
}

  private void loaddatainlist()
  {
      arrayList=databaseHelper.getalldata();
     myAdapter=new MyAdapter(this,arrayList);
     listView.setAdapter(myAdapter);
     myAdapter.notifyDataSetChanged();

  }

@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
    super.onCreateContextMenu(menu, v, menuInfo);
    getMenuInflater().inflate(R.menu.listoption,menu);
}

@Override
public boolean onContextItemSelected(MenuItem item) {
    switch (item.getItemId())
    {
        case R.id.editoption:
            {
            startActivity(new Intent(Home.this, Update.class));
        }
        case R.id.deleteoption:
            {
            Toast.makeText(this, "Delete", Toast.LENGTH_SHORT).show();
        }

       return true;
       default:
           return super.onContextItemSelected(item);
    }

}
public void refresh()
{
    refresh.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            finish();
            startActivity(getIntent());
        }
    });
}

}

public class Update extends AppCompatActivity {

EditText lead,name,company,mobile,address;
Button update;
DatabaseHelper databaseHelper;
SQLiteDatabase dataBase;
ImageButton getrecord;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_update);
    databaseHelper=new DatabaseHelper(this);

    lead=(EditText)findViewById(R.id.lead);
    name=(EditText)findViewById(R.id.updatename);
    company=(EditText)findViewById(R.id.updatecompany_name);
    address=(EditText)findViewById(R.id.updateaddress);
    mobile=(EditText)findViewById(R.id.updatemobile);
    update=(Button)findViewById(R.id.update_button);

}
 }

I displayed all the records which i stored in database but I can not update it.

Answer 1

I am going class by class to make the things easy to understand.

DatabaseHelper class: I am not sure why you have used below section in onCreate() method:

If there is no specific purpose then you can remove it (you can comment for it's use).

Now in Complete your Record model with all the fields which you have used in Client table. Also make the class serialized if it is not. So the Record class will look like-

public class Record implements Serializable {
    ..
    public Record(String sno, lead, String name, String mobile, String companyName, ...) {
        this.sno = sno;
        this.lead = lead;
        this.name = name;
        this.mobile = mobile;
        this.companyName = companyName;
        .
        .
        .
    }
    ..
}

Back to db class. Change the update() method to -

public boolean updateClientInfo(Record record) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
    //Updated code will be like
    ContentValues contentValues = new ContentValues();
    contentValues.put(Column21, record.getLead());
    .
    .
    .
    int count = sqLiteDatabase.update(Table2, contentValues, "SNO = ?", new String[] {record.getSno()});

    return count > 0 ? true : false;
}

In getAllData() method to populate Record model list, pupulate all fields such as SNO etc in the updated Record model (as mentioned above with added fields).

Change the code for delete() method to-

public boolean deleteClientInfo(Record record) {
    SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();

    //Updated code will be
    int count = sqLiteDatabase.update(Table2, "SNO = ?", new String[] {record.getSno()});

    return count > 0 ? true : false;
}   

Update getalldata() method in DB class to -

I have updated your Home activity class so that it will work perfectly for db refresh. You try to notice the differences basically in the following area-

refresh() -> updated, loaddatainlist() -> removed, createAdapter() -> added, refreshListFromDb() -> added, onCreate() updated, onReume() -> added.

public class Home extends AppCompatActivity {

    TextView Name;
    Button refresh, addlead;
    DatabaseHelper databaseHelper;
    SQLiteOpenHelper sqLiteOpenHelper;
    SQLiteDatabase db;
    ListView listView;
    MyAdapter myAdapter;
    ArrayList<Record> arrayList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);
        Name = (TextView) findViewById(R.id.Name);
        addlead = (Button) findViewById(R.id.addlead);
        refresh = (Button) findViewById(R.id.viewlead);
        listView = (ListView) findViewById(R.id.list_view);
        sqLiteOpenHelper = new DatabaseHelper(this);
        db = sqLiteOpenHelper.getReadableDatabase();
        databaseHelper = new DatabaseHelper(this);
        arrayList = new ArrayList<>();
        createAdapter();
        registerForContextMenu(listView);

        Name.setText(getIntent().getStringExtra(MainActivity.user));
        refresh();
        add_lead();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();

        if (id == R.id.mybutton) {
            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setMessage("Are you really want to Logout ?").setCancelable(false)
                    .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            Toast.makeText(getApplicationContext(), "Logout Successfully", Toast.LENGTH_SHORT).show();
                            finish();
                            // startActivity(new Intent(Home.this,MainActivity.class));
                        }
                    }).setNegativeButton("No", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            dialog.cancel();
                        }
                    });
            AlertDialog alertDialog = builder.create();
            alertDialog.show();

        }
        return super.onOptionsItemSelected(item);
    }

    public void add_lead() {
        addlead.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(Home.this, Registration.class));
            }
        });
    }

    private void createAdapter() {
        myAdapter = new MyAdapter(this, arrayList);
        listView.setAdapter(myAdapter);
    }

    private void refreshListFromDb() {
        arrayList = databaseHelper.getAllClientData(arrayList);
        myAdapter.notifyDataSetChanged();

    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
        super.onCreateContextMenu(menu, v, menuInfo);
        getMenuInflater().inflate(R.menu.listoption, menu);
    }

    @Override
    public boolean onContextItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case R.id.editoption: {
            startActivity(new Intent(Home.this, Update.class));
        }
        case R.id.deleteoption: {
            Toast.makeText(this, "Delete", Toast.LENGTH_SHORT).show();
        }

            return true;
        default:
            return super.onContextItemSelected(item);
        }

    }

    public void refresh() {
        refresh.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                refreshListFromDb();
            }
        });
    }

    @Override
        public void onResume() {
            super.onResume();
            refreshListFromDb()
        }
}

When you are calling Update class after longpress call the Intent as-

Intent intent = new Intent(this, Update.class);
intent.putExtra("parcel_record", recordModel); // record model of the index from array list where longpress is made. 
startActivity(intent);

Fetch the record object in Update activity like this-

@Override
protected void onCreate(Bundle savedInstanceState) {
    // Using getParcelableExtra(String key) method
    Record record = (Record) getIntent().getParcelableExtra("parcel_record");
    ....
}

Now populate the fields such as name, mobile in update activity by taking from record model such as

editTextMobile.setText(record.getMobile());

Once user click on Update button, update the record model with the edited value from field such as -

record.setMobile(editTextMobile.getText().toString());
....

and call updateClientInfo(record) of DB helper class.

Hope the detail will help you to get your requirement.

Note: It's my suggestion, use a proper name for the variables and methods such as getingData() to getUserRecord() in DB class, insertData() to insertClientInfo() and so on.

Answer 2

try this:-

lv.setOnItemLongClickListener(new OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
                    int pos, long id) {
                // TODO Auto-generated method stub

                Log.v("long clicked","pos: " + pos);

                return true;
            }
        }); 

if you want to set onLongClick on an adapter item.then just do this**(in onBindViewHolder method of adapter)**:-

    holder.lv.setOnItemLongClickListener(new OnItemLongClickListener() {

        //your code here.i.e updating the database

    }