Develop Reference

Passing data from one listview to another

I have been trying to pass the contact data from my second activity's list view to my main activity's list view, upon clicking the checkbox.But the data doesn't get transferred. How do I fix this?
MainActivity.java
package com.example.artist.sender;
import android.Manifest;
import android.app.AlertDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Parcelable;
import android.provider.ContactsContract;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.text.Editable;
import android.text.TextUtils;
import android.util.SparseBooleanArray;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import org.w3c.dom.Text;
import java.util.ArrayList;
import java.util.List;
import static android.R.id.input;
import static android.app.AlertDialog.*;
public class MainActivity extends AppCompatActivity {
EditText itemText;
Button addButton;
Button sendText;
TextView text;
Button contact;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
itemText = (EditText) findViewById(R.id.editText);
addButton = (Button) findViewById(R.id.button1);
text=(TextView) findViewById(R.id.textView);
addButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (TextUtils.isEmpty(itemText.getText())||(itemText.getText().length()<10)||(itemText.getText().length()>10)) {
itemText.setError("The number is not valid.");
return;
} else {
text.setText(itemText.getText().toString());
itemText.setText("");
return;
}
}
});
Button delete;
delete = (Button) findViewById(R.id.btn2);
delete.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
int con=text.getLineCount();
if(con==0)
Toast.makeText(MainActivity.this, "No number available to delete", Toast.LENGTH_SHORT).show();
else
text.setText("");
}
});
sendText=(Button) findViewById(R.id.btn3);
sendText.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String phoneno = text.getText().toString();
int count = text.getLineCount();
SmsManager smsMgrVar = SmsManager.getDefault();
if (count == 0) {
Toast.makeText(MainActivity.this, "No number available", Toast.LENGTH_SHORT).show();
}
else
if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.SEND_SMS) == PackageManager.PERMISSION_GRANTED)
{
try{
smsMgrVar.sendTextMessage(phoneno, null, "Hey There!", null, null);
Toast.makeText(MainActivity.this, "Message Sent",Toast.LENGTH_LONG).show();
}
catch (Exception ErrVar)
{
Toast.makeText(MainActivity.this, "Message Sending Failed", Toast.LENGTH_SHORT).show();
ErrVar.printStackTrace();
}
}
else
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
{
requestPermissions(new String[]{Manifest.permission.SEND_SMS}, 10);
}
}
}
});
contact =(Button) findViewById(R.id.btn4);
contact.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
{
startActivity(new Intent(MainActivity.this,contacts.class));
}
}
});
String tempholder=getIntent().getStringExtra("Listviewclickvalue");
text.setText(tempholder);
}
}
contacts.java
package com.example.artist.sender;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import java.util.ArrayList;
import android.annotation.TargetApi;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.ContentResolver;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.provider.ContactsContract;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import static android.Manifest.permission.READ_CONTACTS;
public class contacts extends MainActivity {
private static final int REQUEST_READ_CONTACTS = 444;
private ListView mListView;
private ProgressDialog pDialog;
private Handler updateBarHandler;
ArrayList<String> contactList;
Cursor cursor;
int counter;
ListView list;
String temp;
TextView itemText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
pDialog = new ProgressDialog(contacts.this);
pDialog.setMessage("Reading contacts...");
pDialog.setCancelable(false);
pDialog.show();
mListView = (ListView) findViewById(R.id.list);
updateBarHandler = new Handler();
// Since reading contacts takes more time, let's run it on a separate thread.
new Thread(new Runnable() {
#Override
public void run() {
getContacts();
}
}).start();
// Set onclicklistener to the list item.
mListView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//TODO Do whatever you want with the list data
Toast.makeText(getApplicationContext(), "item clicked : \n" + contactList.get(position), Toast.LENGTH_SHORT).show();
}
});
}
private boolean mayRequestContacts() {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
return true;
}
if (checkSelfPermission(READ_CONTACTS) == PackageManager.PERMISSION_GRANTED) {
return true;
}
if (shouldShowRequestPermissionRationale(READ_CONTACTS)) {
requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
} else {
requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
}
return false;
}
/**
* Callback received when a permissions request has been completed.
*/
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions,
int[] grantResults) {
if (requestCode == REQUEST_READ_CONTACTS) {
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
getContacts();
}
}
}
public void getContacts() {
if (!mayRequestContacts()) {
return;
}
contactList = new ArrayList<String>();
String phoneNumber = null;
// String email = null;
Uri CONTENT_URI = ContactsContract.Contacts.CONTENT_URI;
String _ID = ContactsContract.Contacts._ID;
String DISPLAY_NAME = ContactsContract.Contacts.DISPLAY_NAME;
String HAS_PHONE_NUMBER = ContactsContract.Contacts.HAS_PHONE_NUMBER;
Uri PhoneCONTENT_URI = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
String Phone_CONTACT_ID = ContactsContract.CommonDataKinds.Phone.CONTACT_ID;
String NUMBER = ContactsContract.CommonDataKinds.Phone.NUMBER;
/* Uri EmailCONTENT_URI = ContactsContract.CommonDataKinds.Email.CONTENT_URI;
String EmailCONTACT_ID = ContactsContract.CommonDataKinds.Email.CONTACT_ID;
String DATA = ContactsContract.CommonDataKinds.Email.DATA;*/
StringBuffer output;
ContentResolver contentResolver = getContentResolver();
cursor = contentResolver.query(CONTENT_URI, null, null, null, null);
// Iterate every contact in the phone
if (cursor.getCount() > 0) {
counter = 0;
while (cursor.moveToNext()) {
output = new StringBuffer();
// Update the progress message
updateBarHandler.post(new Runnable() {
public void run() {
pDialog.setMessage("Reading contacts : " + counter++ + "/" + cursor.getCount());
}
});
String contact_id = cursor.getString(cursor.getColumnIndex(_ID));
String name = cursor.getString(cursor.getColumnIndex(DISPLAY_NAME));
int hasPhoneNumber = Integer.parseInt(cursor.getString(cursor.getColumnIndex(HAS_PHONE_NUMBER)));
if (hasPhoneNumber > 0) {
output.append("\n First Name:" + name);
//This is to read multiple phone numbers associated with the same contact
Cursor phoneCursor = contentResolver.query(PhoneCONTENT_URI, null, Phone_CONTACT_ID + " = ?", new String[]{contact_id}, null);
while (phoneCursor.moveToNext()) {
phoneNumber = phoneCursor.getString(phoneCursor.getColumnIndex(NUMBER));
output.append("\n Phone number:" + phoneNumber);
}
phoneCursor.close();
/* // Read every email id associated with the contact
Cursor emailCursor = contentResolver.query(EmailCONTENT_URI, null, EmailCONTACT_ID + " = ?", new String[]{contact_id}, null);
while (emailCursor.moveToNext()) {
email = emailCursor.getString(emailCursor.getColumnIndex(DATA));
output.append("\n Email:" + email);
}
emailCursor.close();
String columns[] = {
ContactsContract.CommonDataKinds.Event.START_DATE,
ContactsContract.CommonDataKinds.Event.TYPE,
ContactsContract.CommonDataKinds.Event.MIMETYPE,
};*/
String where = ContactsContract.CommonDataKinds.Event.TYPE + "=" + ContactsContract.CommonDataKinds.Event.TYPE_BIRTHDAY +
" and " + ContactsContract.CommonDataKinds.Event.MIMETYPE + " = '" + ContactsContract.CommonDataKinds.Event.CONTENT_ITEM_TYPE + "' and " + ContactsContract.Data.CONTACT_ID + " = " + contact_id;
String[] selectionArgs = null;
String sortOrder = ContactsContract.Contacts.DISPLAY_NAME;
/*Cursor birthdayCur = contentResolver.query(ContactsContract.Data.CONTENT_URI, columns, where, selectionArgs, sortOrder);
Log.d("BDAY", birthdayCur.getCount()+"");
if (birthdayCur.getCount() > 0) {
while (birthdayCur.moveToNext()) {
String birthday = birthdayCur.getString(birthdayCur.getColumnIndex(ContactsContract.CommonDataKinds.Event.START_DATE));
output.append("Birthday :" + birthday);
Log.d("BDAY", birthday);
}
}
birthdayCur.close();
}*/
// Add the contact to the ArrayList
contactList.add(output.toString());
}
// ListView has to be updated using a ui thread
runOnUiThread(new Runnable() {
#Override
public void run() {
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(), R.layout.contact_text, R.id.text1, contactList);
mListView.setAdapter(adapter);
}
});
// Dismiss the progressbar after 500 millisecondds
updateBarHandler.postDelayed(new Runnable() {
#Override
public void run() {
pDialog.cancel();
}
}, 500);
}
}
//passing the number to the mainactivity's textview through intent
list=(ListView) findViewById(R.id.list);
final String listview[] = new String[list.getCount()];
for (int j = 0; j < list.getCount(); j++) {
View v = list.getChildAt(j);
TextView tv = (TextView) v.findViewById(R.id.text1);
listview[j] = (String) tv.getText();
}
itemText = (TextView) findViewById(R.id.text1);
final String number = itemText.getText().toString();
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, android.R.id.text1, listview);
list.setAdapter(adapter);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if ((number.matches("[0-9]+"))&&(number.length()==10))
temp = listview[position].toString();
Intent intent = new Intent(contacts.this, MainActivity.class);
intent.putExtra("Listviewclickvalue", temp);
startActivity(intent);
}
}
);
}
}
logcat
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.artist.sender/com.example.artist.sender.contacts}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setOnItemClickListener(android.widget.AdapterView$OnItemClickListener)' on a null object reference
This is the logcat for the error. It keeps showing that the setitemOnClickListener keeps referring to a null object whereas, I've already assigned the listview to its respective id.
EDIT:**I've fixed part of the error, by renaming the setContentView(R.layout.activity_main); in the contacts class to setContentView(R.layout.contacts); But now after that, it shows this error, **java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference

If the data in the database, or some other storage, only pass the _id or the location, respectively.
Instead of passing many extras, Android way is, actually, Parcable. Here a nice tutorial from Vogella
public class TestModel implements Parcelable {
String name;
String phoneNumber;
//.....
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(this.name);
dest.writeString(this.phoneNumber);
}
public static final Parcelable.Creator<TestModel> CREATOR = new Parcelable.Creator<TestModel>() {
#Override
public TestModel createFromParcel(Parcel source) {
return new TestModel(source);
}
#Override
public TestModel[] newArray(int size) {
return new TestModel[size];
}
};
}

Passing data from one listview to another textview

I have been trying to pass the contact data from my second activity's list view to my main activity's list view, upon clicking the data.But the app crashes just on clicking the contacts button. How do I fix this?
MainActivity.java
package com.example.artist.sender;
import android.Manifest;
import android.app.AlertDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Parcelable;
import android.provider.ContactsContract;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.text.Editable;
import android.text.TextUtils;
import android.util.SparseBooleanArray;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import org.w3c.dom.Text;
import java.util.ArrayList;
import java.util.List;
import static android.R.id.input;
import static android.app.AlertDialog.*;
public class MainActivity extends AppCompatActivity {
EditText itemText;
Button addButton;
Button sendText;
TextView text;
Button contact;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
itemText = (EditText) findViewById(R.id.editText);
addButton = (Button) findViewById(R.id.button1);
text=(TextView) findViewById(R.id.textView);
addButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (TextUtils.isEmpty(itemText.getText())||(itemText.getText().length()<10)||(itemText.getText().length()>10)) {
itemText.setError("The number is not valid.");
return;
} else {
text.setText(itemText.getText().toString());
itemText.setText("");
return;
}
}
});
Button delete;
delete = (Button) findViewById(R.id.btn2);
delete.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
int con=text.getLineCount();
if(con==0)
Toast.makeText(MainActivity.this, "No number available to delete", Toast.LENGTH_SHORT).show();
else
text.setText("");
}
});
sendText=(Button) findViewById(R.id.btn3);
sendText.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String phoneno = text.getText().toString();
int count = text.getLineCount();
SmsManager smsMgrVar = SmsManager.getDefault();
if (count == 0) {
Toast.makeText(MainActivity.this, "No number available", Toast.LENGTH_SHORT).show();
}
else
if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.SEND_SMS) == PackageManager.PERMISSION_GRANTED)
{
try{
smsMgrVar.sendTextMessage(phoneno, null, "Hey There!", null, null);
Toast.makeText(MainActivity.this, "Message Sent",Toast.LENGTH_LONG).show();
}
catch (Exception ErrVar)
{
Toast.makeText(MainActivity.this, "Message Sending Failed", Toast.LENGTH_SHORT).show();
ErrVar.printStackTrace();
}
}
else
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
{
requestPermissions(new String[]{Manifest.permission.SEND_SMS}, 10);
}
}
}
});
contact =(Button) findViewById(R.id.btn4);
contact.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
{
startActivity(new Intent(MainActivity.this,contacts.class));
}
}
});
String tempholder=getIntent().getStringExtra("Listviewclickvalue");
text.setText(tempholder);
}
contacts.java
package com.example.artist.sender;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import java.util.ArrayList;
import android.annotation.TargetApi;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.ContentResolver;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.provider.ContactsContract;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import static android.Manifest.permission.READ_CONTACTS;
public class contacts extends MainActivity {
private static final int REQUEST_READ_CONTACTS = 444;
private ListView mListView;
private ProgressDialog pDialog;
private Handler updateBarHandler;
ArrayList<String> contactList;
Cursor cursor;
int counter;
ListView list;
String temp;
TextView itemText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.contacts);
pDialog = new ProgressDialog(contacts.this);
pDialog.setMessage("Reading contacts...");
pDialog.setCancelable(false);
pDialog.show();
mListView = (ListView) findViewById(R.id.list);
updateBarHandler = new Handler();
// Since reading contacts takes more time, let's run it on a separate thread.
new Thread(new Runnable() {
#Override
public void run() {
getContacts();
}
}).start();
// Set onclicklistener to the list item.
mListView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//TODO Do whatever you want with the list data
Toast.makeText(getApplicationContext(), "item clicked : \n" + contactList.get(position), Toast.LENGTH_SHORT).show();
}
});
}
private boolean mayRequestContacts() {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
return true;
}
if (checkSelfPermission(READ_CONTACTS) == PackageManager.PERMISSION_GRANTED)
{
return true;
}
if (shouldShowRequestPermissionRationale(READ_CONTACTS)) {
requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
} else {
requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
}
return false;
}
/**
* Callback received when a permissions request has been completed.
*/
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions,
int[] grantResults) {
if (requestCode == REQUEST_READ_CONTACTS) {
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
getContacts();
}
}
}
public void getContacts() {
if (!mayRequestContacts()) {
return;
}
contactList = new ArrayList<String>();
String phoneNumber = null;
// String email = null;
Uri CONTENT_URI = ContactsContract.Contacts.CONTENT_URI;
String _ID = ContactsContract.Contacts._ID;
String DISPLAY_NAME = ContactsContract.Contacts.DISPLAY_NAME;
String HAS_PHONE_NUMBER = ContactsContract.Contacts.HAS_PHONE_NUMBER;
Uri PhoneCONTENT_URI = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
String Phone_CONTACT_ID = ContactsContract.CommonDataKinds.Phone.CONTACT_ID;
String NUMBER = ContactsContract.CommonDataKinds.Phone.NUMBER;
/* Uri EmailCONTENT_URI = ContactsContract.CommonDataKinds.Email.CONTENT_URI;
String EmailCONTACT_ID = ContactsContract.CommonDataKinds.Email.CONTACT_ID;
String DATA = ContactsContract.CommonDataKinds.Email.DATA;*/
StringBuffer output;
ContentResolver contentResolver = getContentResolver();
cursor = contentResolver.query(CONTENT_URI, null, null, null, null);
// Iterate every contact in the phone
if (cursor.getCount() > 0) {
counter = 0;
while (cursor.moveToNext()) {
output = new StringBuffer();
// Update the progress message
updateBarHandler.post(new Runnable() {
public void run() {
pDialog.setMessage("Reading contacts : " + counter++ + "/" + cursor.getCount());
}
});
String contact_id = cursor.getString(cursor.getColumnIndex(_ID));
String name = cursor.getString(cursor.getColumnIndex(DISPLAY_NAME));
int hasPhoneNumber = Integer.parseInt(cursor.getString(cursor.getColumnIndex(HAS_PHONE_NUMBER)));
if (hasPhoneNumber > 0) {
output.append("\n First Name:" + name);
//This is to read multiple phone numbers associated with the same contact
Cursor phoneCursor = contentResolver.query(PhoneCONTENT_URI, null, Phone_CONTACT_ID + " = ?", new String[]{contact_id}, null);
while (phoneCursor.moveToNext()) {
phoneNumber = phoneCursor.getString(phoneCursor.getColumnIndex(NUMBER));
output.append("\n Phone number:" + phoneNumber);
}
phoneCursor.close();
/* // Read every email id associated with the contact
Cursor emailCursor = contentResolver.query(EmailCONTENT_URI, null, EmailCONTACT_ID + " = ?", new String[]{contact_id}, null);
while (emailCursor.moveToNext()) {
email = emailCursor.getString(emailCursor.getColumnIndex(DATA));
output.append("\n Email:" + email);
}
emailCursor.close();
String columns[] = {
ContactsContract.CommonDataKinds.Event.START_DATE,
ContactsContract.CommonDataKinds.Event.TYPE,
ContactsContract.CommonDataKinds.Event.MIMETYPE,
};*/
String where = ContactsContract.CommonDataKinds.Event.TYPE + "=" + ContactsContract.CommonDataKinds.Event.TYPE_BIRTHDAY +
" and " + ContactsContract.CommonDataKinds.Event.MIMETYPE + " = '" + ContactsContract.CommonDataKinds.Event.CONTENT_ITEM_TYPE + "' and " + ContactsContract.Data.CONTACT_ID + " = " + contact_id;
String[] selectionArgs = null;
String sortOrder = ContactsContract.Contacts.DISPLAY_NAME;
/*Cursor birthdayCur = contentResolver.query(ContactsContract.Data.CONTENT_URI, columns, where, selectionArgs, sortOrder);
Log.d("BDAY", birthdayCur.getCount()+"");
if (birthdayCur.getCount() > 0) {
while (birthdayCur.moveToNext()) {
String birthday = birthdayCur.getString(birthdayCur.getColumnIndex(ContactsContract.CommonDataKinds.Event.START_DATE));
output.append("Birthday :" + birthday);
Log.d("BDAY", birthday);
}
}
birthdayCur.close();
}*/
// Add the contact to the ArrayList
contactList.add(output.toString());
}
// ListView has to be updated using a ui thread
runOnUiThread(new Runnable() {
#Override
public void run() {
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(), R.layout.contact_text, R.id.text1, contactList);
mListView.setAdapter(adapter);
}
});
// Dismiss the progressbar after 500 millisecondds
updateBarHandler.postDelayed(new Runnable() {
#Override
public void run() {
pDialog.cancel();
}
}, 500);
}
}
//passing the number to the mainactivity's textview through intent
list=(ListView) findViewById(R.id.list);
final String listview[] = new String[list.getCount()];
for (int j = 0; j < list.getCount(); j++) {
View v = list.getChildAt(j);
TextView tv = (TextView) v.findViewById(R.id.text1);
listview[j] = (String) tv.getText();
}
itemText = (TextView) findViewById(R.id.text1);
final String number = itemText.getText().toString();
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, android.R.id.text1, listview);
list.setAdapter(adapter);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if ((number.matches("[0-9]+"))&&(number.length()==10))
temp = listview[position].toString();
Intent intent = new Intent(contacts.this, MainActivity.class);
intent.putExtra("Listviewclickvalue", temp);
startActivity(intent);
}
}
);
}
logcat
java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference
at com.example.artist.sender.contacts.getContacts(contacts.java:236)
at com.example.artist.sender.contacts$1.run(contacts.java:57)
at java.lang.Thread.run(Thread.java:818)
This is the logcat for the error. It keeps showing that the findViewById keeps referring to a null object whereas, I've already assigned all the variables to their respective ids.

How to add row dynamically in table layout or How to show full db Records in single table Layout

Hello Techie :) i am new to android . i'm developing one app where user is registering with all personal detail and mobile device detail and after user login all the things working fine and met with result but when i'm moving to admin section here i have issue and i'm not getting any idea about this .
Parts of Admin section where i am stuck :-
1) after admin login , all table records should be shown in one table layout here u can say i want to populate all table records in Table Layout .
i try with specific user name and its showing in the table layout but it's not my requirement , i have to show all users in Table layout .
i'm sharing my code here , will u all suggest me what to do next and how can i achieve my requirement.
Thanks for your valuable time :)
//MainActivity.java
package com.example.yadapras.mobiltyemp;
import android.content.Context;
import android.content.Intent; import android.os.Build; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.VectorEnabledTintResources; import android.telephony.TelephonyManager; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.Toast;
/** * Created by yadapras on 6/26/2016. */ public class MainActivity extends AppCompatActivity {
EditText a,b;
String usr,pass;
DatabaseHelper helper = new DatabaseHelper(this);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onButtonClick(View v)
{
if (v.getId() == R.id.BLogin)
{
a = (EditText)findViewById(R.id.userName);
usr = a.getText().toString();
b = (EditText)findViewById(R.id.userPassword);
pass = b.getText().toString();
String password = null;
if( a.getText().toString().length() == 0 || usr == "" || usr == null)
a.setError( " User name is required!" );
if( b.getText().toString().length() == 0 || pass =="" || pass == null)
b.setError( "Password is required!" );
else{
password = helper.searchPass(usr);
}
if (a.getText().toString().equals("admin") && b.getText().toString().equals("admin"))
{
Intent intent = new Intent(getApplicationContext(), AdminDisplay.class);
startActivity(intent);
}else{
if (pass.equals(password) && password != null) {
Intent intent = new Intent(getApplicationContext(), EmpDetail.class);
intent.putExtra("usr", usr);
TelephonyManager telephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
String uid = telephonyManager.getDeviceId();
String manufacturer = Build.MANUFACTURER; // Not used in current scenario
String model = Build.MODEL;
int version = Build.VERSION.SDK_INT;
String versionRelease = Build.VERSION.RELEASE; // not used in current scenario
String msg = "IMEI No: " + uid + "\n" + "Manufacturer is :" + manufacturer + "\n" + "Model is :" + model + "\n" + "Os Version is :" + version + "\n" + "VersionRelease is :" + versionRelease;
Toast toast = Toast.makeText(MainActivity.this, msg, Toast.LENGTH_LONG);
toast.show();
Register r = new Register();
r.setImei_no(uid);
r.setDev_model(model);
r.setOs_version(version);
r.setUname(usr);
helper.updateTable(r); /*For updating table with new Coloumn*/
startActivity(intent);
}
else
{
Toast err_pass = Toast.makeText(MainActivity.this,"UserName and Password don't Match",Toast.LENGTH_SHORT);
err_pass.show();
}
}
}
if (v.getId() == R.id.BSignup)
{
Intent intent = new Intent(getApplicationContext(), Registration.class);
startActivity(intent);
}
}
}
//DatabaseHelper.java
package com.example.yadapras.mobiltyemp;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.ArrayMap;
import android.util.Log;
import org.json.JSONException;
import org.json.JSONObject;
/**
* Created by yadapras on 7/8/2016.
*/
public class DatabaseHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "registrationDB.db";
public static final String TABLE_NAME = "registrations";
public static final String COLUMN_ID = "id";
public static final String COLUMN_USERNAME = "username";
public static final String COLUMN_PASSWORD= "password";
public static final String COLUMN_RE_PASSWORD= "re_password";
public static final String COLUMN_NAME= "name";
public static final String COLUMN_EMAIL= "email";
public static final String COLUMN_PHONE_NO= "phone_no";
/*Adding three coloumn IMEI_NO,OS_Version,Model_Device Respectively*/
public static final String COLUMN_IMEI_NO = "imei_no";
public static final String COLUMN_DEV_MODEL = "dev_model";
public static final String COLUMN_OS_VERSION = "os_version";
SQLiteDatabase sqLiteDatabase;
private static final String TABLE_CREATE = "create table registrations(id integer primary key not null, " +
"username text not null, password text not null, re_password text not null, name text not null, email text not null," +
"phone_no number not null,imei_no text, dev_model text, os_version text);";
public DatabaseHelper(Context context) {
super(context,DATABASE_NAME,null,DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL(TABLE_CREATE);
this.sqLiteDatabase=sqLiteDatabase;
Log.d("#####Table Value",TABLE_CREATE);
}
#Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
String query = "DROP TABLE IF EXISTS " +TABLE_NAME ;
sqLiteDatabase.execSQL(query);
this.onCreate(sqLiteDatabase);
}
public void registerUser(Register r) {
/*Inserting anything in to the dataBase make sure it should be writable*/
sqLiteDatabase = getWritableDatabase();
ContentValues values = new ContentValues();
String query = "select * from registrations";
Cursor cursor = sqLiteDatabase.rawQuery(query,null);
int count = cursor.getCount();
Log.d("##count",""+count);
values.put(COLUMN_ID,count);
Log.d("##id",r.getUname());
values.put(COLUMN_USERNAME,r.getUname());
values.put(COLUMN_PASSWORD,r.getPassword());
values.put(COLUMN_RE_PASSWORD,r.getRe_password());
values.put(COLUMN_NAME,r.getName());
values.put(COLUMN_EMAIL, r.getEmail());
values.put(COLUMN_PHONE_NO, r.getPhone_no());
sqLiteDatabase.insert(TABLE_NAME, null,values); /*this will insert Register object in to the Database*/
sqLiteDatabase.close();
}
public String searchPass(String usr) {
sqLiteDatabase = this.getReadableDatabase();
String query = "select username,password from "+TABLE_NAME;
Cursor cursor = sqLiteDatabase.rawQuery(query,null);
String a,b ; // a and b will be userName and Password respectively
b = "Not Found";
if (cursor.moveToFirst())
{
do {
a = cursor.getString(0);
Log.d("##username from db",a);
if (a.equals(usr))
{
b = cursor.getString(1);
break;
}
}while (cursor.moveToNext());
}
return b;
}
public JSONObject showDetail(String usr) {
sqLiteDatabase = this.getReadableDatabase();
String query ="SELECT * FROM registrations where username='"+usr+"'" ;//"select * from registrations where username = p";
// String query = "SELECT * FROM registrations";
Cursor cursor = sqLiteDatabase.rawQuery(query,null);
JSONObject data = new JSONObject();
if (cursor.moveToFirst()){
do {
int columnsQty = cursor.getColumnCount();
Log.d("###count-->", String.valueOf(columnsQty));
for (int idx=0; idx<columnsQty; ++idx) {
try {
data.put(cursor.getColumnName(idx),cursor.getString(idx));
} catch (JSONException e) {
e.printStackTrace();
}
}
}while (cursor.moveToNext());
}
cursor.close();
Log.d("###Data Value",data.toString());
return data;
}
public void updateTable(Register r) {
SQLiteDatabase db = getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_IMEI_NO,r.getImei_no());
Log.d("###Column_IMEI_NO",r.getImei_no());
cv.put(COLUMN_DEV_MODEL,r.getDev_model());
cv.put(COLUMN_OS_VERSION,r.getOs_version());
db.update(TABLE_NAME,cv,"username = ?",new String[]{r.getUname()});; /*Working for all fields*/
/*SQLiteDatabase db = getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_IMEI_NO,r.getImei_no());
Log.d("###Column_IMEI_NO",r.getImei_no());
cv.put(COLUMN_DEV_MODEL,r.getDev_model());
cv.put(COLUMN_OS_VERSION,r.getOs_version());
String updateQuery = "Update registrations set " + COLUMN_IMEI_NO + " = '"+ r.getImei_no() +"' where " + COLUMN_USERNAME + "="+"'"+ r.getUname() +"'";
db.execSQL(updateQuery);
db.close();*/
}
}
//AdminDisplay.java
package com.example.yadapras.mobiltyemp;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.List;
public class AdminDisplay extends AppCompatActivity {
DatabaseHelper helper = new DatabaseHelper(this);
TextView id,name,email,mobileno,imei_no,dev_model ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.admin_display);
TableLayout table = (TableLayout)findViewById(R.id.tableLayout1) ;
id = (TextView)findViewById(R.id.admin_usr_id);
name = (TextView)findViewById(R.id.admin_Uname);
email = (TextView)findViewById(R.id.admin_usr_email);
mobileno = (TextView)findViewById(R.id.admin_usr_phone);
imei_no = (TextView)findViewById(R.id.admin_usr_imeiNo);
dev_model = (TextView)findViewById(R.id.admin_usr_dev_model);
JSONObject details = helper.showDetail("pcu9044"); // ***Here i'm trying registered user so i'm getting only this user field in TableLayout .***
for (int i=0; i<details.length();i++){
TableRow row = (TableRow)findViewById(R.id.tableRow1);
try {
table.removeView(row);
((TextView)row.findViewById(R.id.admin_usr_id)).setText(details.getString("id"));
((TextView)row.findViewById(R.id.admin_usr_email)).setText(details.getString("email"));
((TextView)row.findViewById(R.id.admin_Uname)).setText(details.getString("name"));
((TextView)row.findViewById(R.id.admin_usr_phone)).setText(details.getString("phone_no"));
((TextView)row.findViewById(R.id.admin_usr_imeiNo)).setText(details.getString("imei_no"));
((TextView)row.findViewById(R.id.admin_usr_dev_model)).setText(details.getString("dev_model"));
table.addView(row);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
i'm attaching screen shot of my output, if yup people have nay doubt please feel free to ask . Thank u in advance .
Result output with my code

The problem that I see here is that when you say:
"i try with specific user name and its showing in the table layout but
it's not my requirement , i have to show all users in Table layout".
By searching for one single user from the database, you are only retrieving a single record in the database that is associated with the username you are searching for. Your method helper.showDetail() returns a single JSONObject - this object corresponds to the record in the database where username = pcu9044.
If I am understanding your situation correctly, you need to call a method that selects ALL of the records from the database in order to display what you want on the screen. Your helper.showDetail() will be a good start, but you can modify code slightly to achieve what you'd like.
I would recommend using either a list or array of JSONObjects instead of a single JSONObject. Initialize your data structure before you enter the if (cursor.moveToFirst()) conditional (like you have it now), but within each iteration of the loop, you create a new object, fill it with what the cursor returns for that row, and then add it to the structure. The code would look something like this:
public JSONArray showDetail() {
sqLiteDatabase = this.getReadableDatabase();
String query ="SELECT * FROM registrations";// * THIS WILL RETURN ALL RECORDS IN REGISTRATIONS
Cursor cursor = sqLiteDatabase.rawQuery(query,null);
//JSONObject data = new JSONObject(); *change this to an array
JSONArray data = new JSONArray();
if (cursor.moveToFirst()){
do {
int columnsQty = cursor.getColumnCount();
Log.d("###count-->", String.valueOf(columnsQty));
// Must create a new object each time you iterate to a new row to add to the array
JSONObject record = new JSONObject();
for (int idx=0; idx<columnsQty; ++idx) {
try {
// Fill the object
record.put(cursor.getColumnName(idx),cursor.getString(idx));
} catch (JSONException e) {
e.printStackTrace();
}
}
// Add the object to the array and repeat
data.put(record);
}while (cursor.moveToNext());
}
cursor.close();
Log.d("###Data Value",data.toString());
return data;
}
If you do it this way, your helper.showDetail() will return an array filled with objects that each symbolize a row. From there, your AdminDisplay.java should then cycle through the array, grab each object, and fill a new row with the information you need.
Hope this helps!

Hello Techie :) I solved my problem after reading many articles on Table Layout over Internet. i'm giving this problems solution with Table-Layout hope this will help others .
AdminDisplay.java # Editable Version
package com.example.yadapras.mobiltyemp;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.JsonReader;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.List;
public class AdminDisplay extends AppCompatActivity {
TableLayout tableLayout;
private SQLiteDatabase db;
private Context context ;
DatabaseHelper helper = new DatabaseHelper(this);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.admin_display);
context = this;
DatabaseHelper helper = new DatabaseHelper(this);
tableLayout = (TableLayout)findViewById(R.id.tableLayout1) ;
TableRow rowHeader = new TableRow(context);
rowHeader.setBackgroundColor(Color.parseColor("#c0c0c0"));
rowHeader.setLayoutParams(new TableLayout.LayoutParams(TableLayout.LayoutParams.MATCH_PARENT,
TableLayout.LayoutParams.WRAP_CONTENT));
String[] headerText={"ID","USERNAME","EMAIL","PHONE_NO","IMEI_NO","DEV_MODEL"};
for(String c:headerText) {
TextView tv = new TextView(this);
tv.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.WRAP_CONTENT,
TableRow.LayoutParams.WRAP_CONTENT));
tv.setGravity(Gravity.CENTER);
tv.setTextSize(18);
tv.setPadding(5, 5, 5, 5);
tv.setText(c);
rowHeader.addView(tv);
}
tableLayout.addView(rowHeader);
SQLiteDatabase db = helper.getReadableDatabase();
db.beginTransaction();
try
{
String selectQuery = "SELECT * FROM "+ DatabaseHelper.TABLE_NAME;
Cursor cursor = db.rawQuery(selectQuery,null);
if(cursor.getCount() >0)
{
while (cursor.moveToNext()) {
// Read columns data
int id = cursor.getInt(cursor.getColumnIndex("id"));
String user_name= cursor.getString(cursor.getColumnIndex("username"));
String email= cursor.getString(cursor.getColumnIndex("email"));
String phone_no = cursor.getString(cursor.getColumnIndex("phone_no"));
String imei_no = cursor.getString(cursor.getColumnIndex("imei_no"));
String dev_model = cursor.getString(cursor.getColumnIndex("dev_model"));
// dara rows
TableRow row = new TableRow(context);
row.setLayoutParams(new TableLayout.LayoutParams(TableLayout.LayoutParams.MATCH_PARENT,
TableLayout.LayoutParams.WRAP_CONTENT));
String[] colText={id+"",user_name,email,phone_no,imei_no,dev_model};
for(String text:colText) {
TextView tv = new TextView(this);
tv.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.WRAP_CONTENT,
TableRow.LayoutParams.WRAP_CONTENT));
tv.setGravity(Gravity.CENTER);
tv.setTextSize(16);
tv.setPadding(5, 5, 5, 5);
tv.setText(text);
row.addView(tv);
}
tableLayout.addView(row);
}
}
db.setTransactionSuccessful();
}
catch (SQLiteException e)
{
e.printStackTrace();
}
finally
{
db.endTransaction();
// End the transaction.
db.close();
// Close database
}
}
}

Remove table.removeView(row); from the loop, if not you will get only one row at the end of the loop as it removes the previous row when a new row is added
for (int i=0; i<details.length();i++){
TableRow row = (TableRow)findViewById(R.id.tableRow1);
try {
((TextView)row.findViewById(R.id.admin_usr_id)).setText(details.getString("id"));
((TextView)row.findViewById(R.id.admin_usr_email)).setText(details.getString("email"));
((TextView)row.findViewById(R.id.admin_Uname)).setText(details.getString("name"));
((TextView)row.findViewById(R.id.admin_usr_phone)).setText(details.getString("phone_no"));
((TextView)row.findViewById(R.id.admin_usr_imeiNo)).setText(details.getString("imei_no"));
((TextView)row.findViewById(R.id.admin_usr_dev_model)).setText(details.getString("dev_model"));
table.addView(row);
} catch (JSONException e) {
e.printStackTrace();
}
}

Hi try this method i have just updated a method of your code, You can replace with your own method by.
Valiable isAdmin is true when admin get detail and false when user.
public JSONObject showDetail(String usr, boolean isAdmin)
{
sqLiteDatabase = this.getReadableDatabase();
String query = "";
if (isAdmin)
query = "SELECT * FROM registrations";
else
query ="SELECT * FROM registrations where username='"+usr+"'" ;//"select * from registrations where username = p";
Cursor cursor = sqLiteDatabase.rawQuery(query,null);
JSONObject data = new JSONObject();
if (cursor.moveToFirst()){
do {
int columnsQty = cursor.getColumnCount();
Log.d("###count-->", String.valueOf(columnsQty));
for (int idx=0; idx<columnsQty; ++idx) {
try {
data.put(cursor.getColumnName(idx),cursor.getString(idx));
} catch (JSONException e) {
e.printStackTrace();
}
}
}while (cursor.moveToNext());
}
cursor.close();
Log.d("###Data Value",data.toString());
return data;
}
It may help you and Let me know if any query you have.

How to insert selected image in a SqlLite database ?

My code is not inserting image in database. How can I insert selected image in the database, and also retrieve it ? I'm following this tutorial:
http://vimaltuts.com/android-tutorial-for-beginners/android-sqlite-database-example
What modifications the code below requires to insert selected image in database ?
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
public class AddEditCountry extends Activity {
private long rowID;
private EditText nameEt;
private EditText capEt;
private EditText codeEt;
private EditText Donedate;
private EditText Notes;
private EditText Person;
private ImageView imageView1;
Bitmap yourSelectedImage;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.add_country);
nameEt = (EditText) findViewById(R.id.Address);
capEt = (EditText) findViewById(R.id.Stage);
codeEt = (EditText) findViewById(R.id.Dueby);
Donedate = (EditText) findViewById(R.id.Donedate);
Notes = (EditText) findViewById(R.id.Notes);
Person = (EditText) findViewById(R.id.Person);
imageView1 = (ImageView) findViewById(R.id.imageView1);
Button Browse = (Button) findViewById(R.id.Browse);
Browse.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, 0);
}
});
Bundle extras = getIntent().getExtras();
if (extras != null)
{
rowID = extras.getLong("row_id");
nameEt.setText(extras.getString("name"));
capEt.setText(extras.getString("cap"));
codeEt.setText(extras.getString("code"));
Donedate.setText(extras.getString("Location"));
Notes.setText(extras.getString("Notes"));
Person.setText(extras.getString("Person"));
}
Button saveButton =(Button) findViewById(R.id.saveBtn);
saveButton.setOnClickListener(new OnClickListener() {
public void onClick(View v)
{
if (nameEt.getText().length() != 0)
{
AsyncTask<Object, Object, Object> saveContactTask =
new AsyncTask<Object, Object, Object>()
{
#Override
protected Object doInBackground(Object... params)
{
saveContact();
return null;
}
#Override
protected void onPostExecute(Object result)
{
finish();
}
};
saveContactTask.execute((Object[]) null);
}
else
{
AlertDialog.Builder alert = new
AlertDialog.Builder(AddEditCountry.this);
alert.setTitle(R.string.errorTitle);
alert.setMessage(R.string.errorMessage);
alert.setPositiveButton(R.string.errorButton, null);
alert.show();
}
}
});
}
private void saveContact()
{
// ByteArrayOutputStream outStr = new ByteArrayOutputStream();
// yourSelectedImage.compress(CompressFormat.PNG, 100, outStr);
// byte[] blob = outStr.toByteArray();
DatabaseConnector dbConnector = new DatabaseConnector(this);
if (getIntent().getExtras() == null)
{
dbConnector.insertContact(nameEt.getText().toString(),
capEt.getText().toString(),
codeEt.getText().toString(),
Donedate.getText().toString(),
Notes.getText().toString(),
Person.getText().toString()
//,blob
);
}
else
{
dbConnector.updateContact(rowID,
nameEt.getText().toString(),
capEt.getText().toString(),
codeEt.getText().toString(),
Donedate.getText().toString(),
Notes.getText().toString(),
Person.getText().toString()
//, blob
);
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent
imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
switch(requestCode) {
case 0:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage,
filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex); // file path
of selected image
cursor.close();
// Convert file path into bitmap image using below
line.
yourSelectedImage = BitmapFactory.decodeFile(filePath);
// put bitmapimage in your imageview
imageView1.setImageBitmap(yourSelectedImage);
}
}
}
}
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class DatabaseConnector {
private static final String DB_NAME = "WorldCountries";
private SQLiteDatabase database;
private DatabaseOpenHelper dbOpenHelper;
public DatabaseConnector(Context context) {
dbOpenHelper = new DatabaseOpenHelper(context, DB_NAME, null, 1);
}
public void open() throws SQLException
{
//open database in reading/writing mode
database = dbOpenHelper.getWritableDatabase();
}
public void close()
{
if (database != null)
database.close();
}
public void insertContact(String name, String cap, String code, String
LocationEd, String Notes, String Person)
///,byte[] blob)
{
ContentValues newCon = new ContentValues();
newCon.put("name", name);
newCon.put("cap", cap);
newCon.put("code", code);
newCon.put("Location",LocationEd);
newCon.put("Notes",Notes);
newCon.put("Person",Person);
// newCon.put("Image", blob);
open();
database.insert("country", null, newCon);
close();
}
public void updateContact(long id, String name, String
cap,String code,String LocationEd, String Notes, String Person)
//,byte[] blob)
{
ContentValues editCon = new ContentValues();
editCon.put("name", name);
editCon.put("cap", cap);
editCon.put("code", code);
editCon.put("Location", LocationEd);
editCon.put("Notes", Notes);
editCon.put("Person", Person);
// editCon.put("Image", blob);
open();
database.update("country", editCon, "_id=" + id, null);
close();
}
public Cursor getAllContacts()
{
return database.query("country", new String[] {"_id",
"name"},
null, null, null, null, "name");
}
public Cursor getOneContact(long id)
{
return database.query("country", null, "_id=" + id, null,
null, null, null);
}
public void deleteContact(long id)
{
open();
database.delete("country", "_id=" + id, null);
close();
}
}
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseOpenHelper extends SQLiteOpenHelper {
public DatabaseOpenHelper(Context context, String name,
CursorFactory factory, int version) {
super(context, name, factory, version);
}
#Override
public void onCreate(SQLiteDatabase db) {
String createQuery = "CREATE TABLE country (_id integer primary key
autoincrement,name text,cap text,code text,Location double,Notes text,Person
text,blob BLOB);";
db.execSQL(createQuery);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
import java.io.ByteArrayInputStream;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class ViewCountry extends Activity {
private long rowID;
private TextView nameTv;
private TextView capTv;
private TextView codeTv;
private TextView Locationlb;
private TextView Noteslb;
private TextView Personlb;
byte[] byteImage2 = null;
private ImageView imageView2;
Bitmap yourSelectedImage;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.view_country);
setUpViews();
Bundle extras = getIntent().getExtras();
rowID = extras.getLong(CountryList.ROW_ID);
}
private void setUpViews() {
nameTv = (TextView) findViewById(R.id.nameText);
capTv = (TextView) findViewById(R.id.capText);
codeTv = (TextView) findViewById(R.id.codeText);
Locationlb = (TextView) findViewById(R.id.Location_lbl);
Noteslb = (TextView) findViewById(R.id.Notes_lbl);
Personlb = (TextView) findViewById(R.id.Person_lbl);
imageView2= (ImageView) findViewById(R.id.imageView2);
Button Browse2 = (Button) findViewById(R.id.Browse2);
Browse2.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, 0);
}
});
}
#Override
protected void onResume()
{
super.onResume();
new LoadContacts().execute(rowID);
}
private class LoadContacts extends AsyncTask<Long, Object, Cursor>
{
DatabaseConnector dbConnector = new DatabaseConnector(ViewCountry.this);
#Override
protected Cursor doInBackground(Long... params)
{
dbConnector.open();
return dbConnector.getOneContact(params[0]);
}
#Override
protected void onPostExecute(Cursor result)
{
super.onPostExecute(result);
result.moveToFirst();
// get the column index for each data item
int nameIndex = result.getColumnIndex("name");
int capIndex = result.getColumnIndex("cap");
int codeIndex = result.getColumnIndex("code");
int LocationIndex = result.getColumnIndex("Location");
int NotesIndex = result.getColumnIndex("Notes");
int PersonIndex = result.getColumnIndex("Person");
// byte[] blob = result.getBlob("image");
// byte[] data = result.getBlob(result.getColumnIndex("image"));
// byte[] blob result.getColumnIndex(MyBaseColumn.MyTable.ImageField));
nameTv.setText(result.getString(nameIndex));
capTv.setText(result.getString(capIndex));
codeTv.setText(result.getString(codeIndex));
Locationlb.setText(result.getString(LocationIndex));
Noteslb.setText(result.getString(NotesIndex));
Personlb.setText(result.getString(PersonIndex));
// ByteArrayInputStream input = new ByteArrayInputStream(byteImage2);
// Bitmap bit = BitmapFactory.decodeStream(input);
// imageView2.setImageBitmap(bit);
// imageView2.setImageURI(byteImage2);
imageView2.setImageBitmap(yourSelectedImage);
result.close();
dbConnector.close();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu)
{
super.onCreateOptionsMenu(menu);
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.view_country_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item)
{
switch (item.getItemId())
{
case R.id.editItem:
Intent addEditContact =
new Intent(this, AddEditCountry.class);
addEditContact.putExtra(CountryList.ROW_ID, rowID);
addEditContact.putExtra("name", nameTv.getText());
addEditContact.putExtra("cap", capTv.getText());
addEditContact.putExtra("code", codeTv.getText());
addEditContact.putExtra("Location", Locationlb.getText());
addEditContact.putExtra("Notes", Noteslb.getText());
addEditContact.putExtra("Person", Personlb.getText());
// addEditContact.putExtra("blob", yourSelectedImage);
startActivity(addEditContact);
return true;
case R.id.deleteItem:
deleteContact();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
private void deleteContact()
{
AlertDialog.Builder alert = new AlertDialog.Builder(ViewCountry.this);
alert.setTitle(R.string.confirmTitle);
alert.setMessage(R.string.confirmMessage);
alert.setPositiveButton(R.string.delete_btn,
new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int button)
{
final DatabaseConnector dbConnector =
new DatabaseConnector(ViewCountry.this);
AsyncTask<Long, Object, Object> deleteTask =
new AsyncTask<Long, Object, Object>()
{
#Override
protected Object doInBackground(Long... params)
{
dbConnector.deleteContact(params[0]);
return null;
}
#Override
protected void onPostExecute(Object result)
{
finish();
}
};
deleteTask.execute(new Long[] { rowID });
}
}
);
alert.setNegativeButton(R.string.cancel_btn, null).show();
}
protected void onActivityResult(int requestCode, int resultCode, Intent
imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
switch(requestCode) {
case 0:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(selectedImage,
filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String filePath = cursor.getString(columnIndex); // file path
of selected image
cursor.close();
// Convert file path into bitmap image using below
line.
yourSelectedImage = BitmapFactory.decodeFile(filePath);
// put bitmapimage in your imageview
imageView2.setImageBitmap(yourSelectedImage);
}
}
}
}

Do not put images into database. Keep the file on the filesystem (SD card or internal storage) and put reference to it into database. But do not put images directly.

There's no need to put a binary blob in a database. The primary goal of a database is to be queried, ie it organizes data so that it's fast to locate it later. An image is a sequence of bytes, and you won't be able to filter your query based on it, so simply store the image in the filesystem, and maybe adopt a convention that it will be named after the row's ID.

listview items disappearing

So.. my listview items are disappearing after they're scrolled off the screen. They're there, you scoll down, back up, and they're gone. After rotation they reappear, but I have no idea why this is happening.
package com.teslaprime.prirt;
import android.app.Activity;
import android.os.Bundle;
import android.content.Intent;
import android.content.Context;
import android.content.ContentValues;
import android.view.View;
import android.view.ViewGroup;
import android.view.LayoutInflater;
import android.widget.CheckBox;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.TextView;
import android.widget.ListView;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.Cursor;
import java.util.ArrayList;
import java.util.List;
import java.util.Date;
public class TaskList extends Activity {
List<Task> tasks = new ArrayList<Task>();
TaskAdapter adapter = null;
SQLiteDatabase db = null;
public void populateList(){
adapter = new TaskAdapter();
adapter.clear();
Cursor cur = db.query("tasks",null,null,null,null,null,"timestamp");
cur.moveToFirst();
int anchor = 0;
while (cur.isAfterLast() == false) {
if (cur.getInt(cur.getColumnIndex("completed")) == 1) {
Task task = new Task(cur.getString(cur.getColumnIndex("name")),cur.getString(cur.getColumnIndex("type")));
task.id = cur.getInt(cur.getColumnIndex("id"));
task.completed = 1;
adapter.add(task);
anchor = anchor+1;
}
cur.moveToNext();
}
cur.moveToFirst();
while (cur.isAfterLast() == false) {
if (cur.getInt(cur.getColumnIndex("completed")) == 0) {
Task task = new Task(cur.getString(cur.getColumnIndex("name")),cur.getString(cur.getColumnIndex("type")));
task.id = cur.getInt(cur.getColumnIndex("id"));
adapter.add(task);
}
cur.moveToNext();
}
cur.close();
for (int i = tasks.size(); i <= 8; i++) {
adapter.add(new Task());
}
ListView list = (ListView) findViewById(R.id.tasks);
list.setAdapter(adapter);
list.setSelection(anchor);
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Intent setupProcess = new Intent (TaskList.this, SetupWelcome.class);
boolean first = checkDatabase() ? true : false;
db = openOrCreateDatabase("priRT.db",
SQLiteDatabase.CREATE_IF_NECESSARY,null);
db.setVersion(1);
db.setLockingEnabled(true);
db.execSQL("create table if not exists tasks ("
+ "id integer primary key autoincrement,"
+ "name text,"
+ "time integer,"
+ "completed integer,"
+ "timestamp integer,"
+ "spacer integer,"
+ "type text);");
db.execSQL("create table if not exists schedule ("
+ "id integer primary key autoincrement,"
+ "hours_free integer);");
if (first) { startActivityForResult(setupProcess,0); }
populateList();
Button add = (Button) findViewById(R.id.addTask);
add.setOnClickListener(onAdd);
}
public View.OnClickListener closeTaskListener = new View.OnClickListener(){
public void onClick(View v){
int pos = (Integer) (v.getTag());
Task task = adapter.getItem(pos);
ContentValues values = new ContentValues();
if (task.completed == 1){
values.put("completed", 0);
task.completed = 0;
} else {
values.put("completed", 1);
task.completed = 1;
}
Long time = new Date().getTime();
values.put("timestamp", time);
db.update("tasks", values, "id='"+task.id+"'", null);
populateList();
}
};
private boolean checkDatabase() {
SQLiteDatabase checkDB = null;
try {
checkDB = SQLiteDatabase.openDatabase(
"/data/data/com.teslaprime.prirt/databases/priRT.db", null,
SQLiteDatabase.OPEN_READONLY);
checkDB.close();
} catch (SQLiteException e) {}
return checkDB == null ? true : false;
}
private View.OnClickListener onAdd = new View.OnClickListener() {
public void onClick(View view) {
Intent addTask = new Intent (view.getContext(), TaskEntry.class);
startActivityForResult(addTask, 2);
}
};
protected void onActivityResult(int req, int res, Intent data) {
if (req == 0 && res == RESULT_OK) {
Intent setup = new Intent (TaskList.this, SetupWizard.class);
startActivityForResult(setup, 1);
}
if (req == 2 && res == RESULT_OK) {
Task task = new Task(data.getStringExtra("name"),data.getStringExtra("type"));
adapter.add(task);
ContentValues values = new ContentValues();
values.put("name", data.getStringExtra("name"));
values.put("type", data.getStringExtra("type"));
values.put("completed", 0);
values.put("spacer", 0);
db.insert("tasks", null, values);
Cursor cur = db.query("tasks", null, null, null, null, null, null);
cur.moveToLast();
task.id = cur.getInt(cur.getColumnIndex("id"));
cur.close();
populateList();
}
}
class TaskAdapter extends ArrayAdapter<Task> {
TaskAdapter() {super(TaskList.this,R.layout.task,tasks);}
private List<Task> taskList;
private Context context;
public View getView(int pos, View convertView, ViewGroup parent) {
View task = convertView;
if (convertView == null) {
LayoutInflater inflater = getLayoutInflater();
task = inflater.inflate(R.layout.task,null);
}
if (tasks.get(pos).spacer == 0) {
TextView taskName = (TextView) task.findViewById(R.id.name);
TextView taskType = (TextView) task.findViewById(R.id.type);
taskName.setText(tasks.get(pos).name);
taskType.setText(tasks.get(pos).type);
Task taskList = adapter.getItem(pos);
CheckBox closeTask = (CheckBox) task.findViewById(R.id.closeTask);
if (taskList.completed == 0) {
closeTask.setChecked(false);
} else {
closeTask.setChecked(true);
}
closeTask.setTag(pos);
closeTask.setOnClickListener(closeTaskListener);
} else {
CheckBox closeTask = (CheckBox) task.findViewById(R.id.closeTask);
task.setVisibility(View.GONE);
task.setFocusable(false);
task.setClickable(false);
}
return task;
}
}
}

It may be happening because of the background color of surface in which list appears. Try setting the background color to white in linerlayout and text view coolr black then scroll the through the list view again.