Develop Reference

How do I create a button dynamically based on user input?

I am trying to make an app where the user types in text and presses enter and a button is dynamically placed on a different activity with its text set as what the user inputs. I am not sure how to do this, I was thinking of saving the user input in a sharedPreference but I am not sure where to go from there.
package com.example.opisa;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class AddGoalsActivity extends AppCompatActivity {
// Create object of SharedPreferences.
SharedPreferences sharedPref= getSharedPreferences("mypref", 0);
//now get Editor
SharedPreferences.Editor editor= sharedPref.edit();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_goals);
}
public void addGoalText(View view) {
EditText name = (EditText) findViewById(R.id.editText1);
TextView mText = (TextView) findViewById(R.id.textView);
if (name.getText().toString().isEmpty()) {
mText.setText("Didnt type anything");
} else {
mText.setText(name.getText().toString());
}
}
//put your value
editor.putString("goals", name);
//commits your edits
editor.commit();
}
After the user types in what he wants,I would like the mText to be the value of text on a button that dynamically appears on a different activity.

In Your First Activity Write
public class AddGoalsActivity extends AppCompatActivity {
// Create object of SharedPreferences.
SharedPreferences setValue ;
//now get Editor
SharedPreferences.Editor valueEditor;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_goals);
setValue = getSharedPreferences("key",Context.MODE_PRIVATE);
}
public void addGoalText() {
valueEditor = setValue.edit();
EditText name = (EditText) findViewById(R.id.editText1);
TextView mText = (TextView) findViewById(R.id.textView);
if (name.getText().toString().isEmpty()) {
mText.setText("Didnt type anything");
valueEditor.putString("key","Didn't type");
} else {
mText.setText(name.getText().toString());
valueEditor.putString("key", String.valueOf(name.getText()));
}
valueEditor.apply();
}
}
If you are calling addGoalText somewhere , if not use onchangelistener
In Your Second Activity in which you have button
public class SecondActivity extends AppCompatActivity {
SharedPreferences setValue ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);// your layout
setValue = getSharedPreferences("key",Context.MODE_PRIVATE);
Button your_button =findViewById(R.id.buttonId);//write your own ID
String S = setValue.getString("key","defaultValue");
your_button.setText(S);
}
}

button click to different activity depending upon cases

i have static page for no internet connection....this i have to use in two actvity....the static page for no internet connection has tap to retry button...
on that tap to retry button i have to go different activity
scenerio:---------
1.when im splash activity(no internet) ---> it should load homeactvivity
2.when im contact us activity(no internet) ---> it should load contact us activity
need help how to do it???
i have got suggestion like Use some flag like isFromSplash of Boolean type which will be true when nav from splash and false when contact us...
how should i implement??????
binding.btnTaptoretry.setOnClickListener {
if (this.isDeviceOnlineStatus(this)){
if (isFromSplash==true) { //this is red `isFromSplash`
val intent = Intent(this, HomeActivity::class.java)
startActivity(intent)
finish()
}
else{
val intent = Intent(this, AboutUsActivity::class.java)
startActivity(intent)
finish()
}
}
}

Splash Activity.Java
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import static com.saqib.app2.RetryActivity.SOURCE;
import static com.saqib.app2.RetryActivity.SPLASH;
public class SplashActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(!Utils.isInternetConnection(this)){
Intent intent = new Intent(SplashActivity.this, RetryActivity.class);
intent.putExtra(SOURCE, SPLASH);
startActivity(intent);
finish();
return;
}
setContentView(R.layout.activity_main);
}
}
Contact activity.java
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import static com.saqib.app2.RetryActivity.CONTACT;
import static com.saqib.app2.RetryActivity.SOURCE;
import static com.saqib.app2.RetryActivity.SPLASH;
public class ContactActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(!Utils.isInternetConnection(this)){
Intent intent = new Intent(ContactActivity.this, RetryActivity.class);
intent.putExtra(SOURCE, CONTACT);
startActivity(intent);
finish();
return;
}
setContentView(R.layout.activity_contact);
}
}
Utils.Java
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
public class Utils {
public static boolean isInternetConnection(Context context){
ConnectivityManager cm =(ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
boolean isConnected = activeNetwork != null &&
activeNetwork.isConnectedOrConnecting();
return isConnected;
}
}
RetryActivity.java (for retry to go to specified activity)
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Switch;
public class RetryActivity extends AppCompatActivity {
public static final String SPLASH = "SPLASH";
public static final String CONTACT = "CONTACT";
public static final String SOURCE = "SOURCE";
Button btnRetry;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_retry);
Intent intent = getIntent();
final String source = intent.getExtras().getString(SOURCE);
btnRetry = findViewById(R.id.btnRetry);
btnRetry.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if(Utils.isInternetConnection(RetryActivity.this)) {
switch (source) {
case SPLASH:
startActivity(new Intent(RetryActivity.this, SplashActivity.class));
finish();
break;
case CONTACT:
startActivity(new Intent(RetryActivity.this, ContactActivity.class));
finish();
break;
}
}
}
});
}
}
Used Intent to send data and receive either it comes from splash or contact.
Intent intent = getIntent();
final String source = intent.getExtras().getString(SOURCE);
This is the magic from where get the history. From where it came.

Use this code
class MainActivity : AppCompatActivity(){
lateinit var button : Button
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
button = findViewById(R.id.button1)
button.setOnClickListener(listener)
}
val listener= View.OnClickListener { view ->
when (view.getId()) {
if(view.getid == R.id.button1)-> {
// Do some work here
}
}
}
}

Shared Preference not holding session (Android K)

I am having a project which uses Shared Preferences for Session Management. Everything is fine with the code but what really annoying is that the app is holding the session in Android Lollipop and above but unfortunately it is not holding the same for Android Kitkat and below. The session is lost whenever the app is closed and you have to lo in again. Following are the codes, I am using:
Session.java
package com.saptak.disputesession;
import android.content.Context;
import android.content.SharedPreferences;
import java.util.HashMap;
/**
* Created by Saptak Das on 27-02-2017.
*/
public class Session {
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
Context context;
public static String KEY_FNAME="namef";
public static String KEY_LNAME="namel";
public static String IS_LOGIN;
public Session(Context context) {
this.context = context;
sharedPreferences=context.getSharedPreferences("userdetails",0);
editor=sharedPreferences.edit();
}
public void CreateLoginSession(String fname,String lname)
{
editor.putString(KEY_FNAME,fname);
editor.putString(KEY_LNAME,lname);
editor.putString(IS_LOGIN,"logged");
editor.commit();
}
public HashMap<String,String> getdetails()
{
HashMap<String,String> details=new HashMap<>();
details.put(KEY_FNAME,sharedPreferences.getString(KEY_FNAME,null));
details.put(KEY_LNAME,sharedPreferences.getString(KEY_LNAME,null));
return details;
}
public boolean loginstatus()
{
if(sharedPreferences.getString(IS_LOGIN,"unlogged").equals("logged"))
{
return true;
}
else
{
return false;
}
}
public void logoutac()
{
editor.clear();
editor.commit();
}
}
Login.java
package com.saptak.disputesession;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
/**
* Created by Saptak Das on 27-02-2017.
*/
public class Login extends Activity {
Button login;
EditText first,last;
Session session;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout);
session=new Session(getApplicationContext());
login=(Button)findViewById(R.id.log);
first=(EditText)findViewById(R.id.fname);
last=(EditText)findViewById(R.id.lname);
login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
session.CreateLoginSession(first.getText().toString(),last.getText().toString());
startActivity(new Intent(getApplicationContext(), MainActivity.class));
finish();
}
});
}
}
MainActivity.java
package com.saptak.disputesession;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.HashMap;
public class MainActivity extends AppCompatActivity {
Session session;
Boolean flag;
TextView tf,tl;
Button logout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
session=new Session(getApplicationContext());
tf=(TextView)findViewById(R.id.xfname);
tl=(TextView)findViewById(R.id.xlname);
logout=(Button)findViewById(R.id.xlogout);
flag=session.loginstatus();
if(flag==false)
{
startActivity(new Intent(getApplicationContext(),Login.class));
finish();
}
HashMap<String,String> details=session.getdetails();
tf.setText(details.get(Session.KEY_FNAME));
tl.setText(details.get(Session.KEY_LNAME));
logout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
session.logoutac();
startActivity(new Intent(getApplicationContext(),Login.class));
finish();
}
});
}
}
This problem is getting on my nerves now as the app is perfectly coded, please help me out. Thanks in advance!
Update:
Please note, the problem is not about deleting the session, its completely opposite. The session is logging itself out everytime i am closing the app. and this problem is only in case of Android Kitkat and below, works fine for Android Lollipop and above

SharedPreferences allow you to save and retrieve data in the form of key,value pair.
Mistake
public static String IS_LOGIN="logged"; // Init here
FYI
Session are useful when you want to store user data globally through
out the application.
Rectify your method
public void CreateLoginSession(String fname,String lname)
{
editor.remove(KEY_FNAME); //Remove at first
editor.remove(KEY_LNAME);
editor.remove(IS_LOGIN);
editor.putString(KEY_FNAME,fname);
editor.putString(KEY_LNAME,lname);
editor.putString(IS_LOGIN,"logged");
editor.commit();
}

Android: Settings "onResume"?

I'm working on a Android App and the layout and all the "android" specific stuff made a friend of my. I only was responsible for the "app" itself.
Nevertheless,
I would like to change some settings, e.g. change the server the stats produced by the app, should be transfered.
Here is the Settings.java:
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.Date;
public class Settings extends Activity {
private Context mContext;
private SharedPreferences mPrefs;
private SharedPreferences.Editor mPrefEditor;
private EditText textName, textIP;
private RadioButton rdOnline, rdOffline;
private RadioGroup rdGroup;
private Button butSpeichern;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext = this;
setContentView(R.layout.activity_settings);
mPrefs = PreferenceManager.getDefaultSharedPreferences(mContext);
mPrefEditor = mPrefs.edit();
textName = (EditText) findViewById(R.id.txtBenutzer);
textIP = (EditText) findViewById(R.id.txtIP);
rdOffline = (RadioButton) findViewById(R.id.rdOffline);
rdOnline = (RadioButton) findViewById(R.id.rdOnline);
rdGroup = (RadioGroup) findViewById(R.id.radioDB);
butSpeichern = (Button) findViewById(R.id.btnSpeichern);
butSpeichern.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
saveSettings();
}
});
//Online default an
rdOnline.setChecked(true);
rdOffline.setChecked(false);
loadSettings();
//ggf. Lan
System.out.println("online");
if(automatischLAN()){
setLan();
}
}
private void saveSettings()
{
mPrefEditor.putBoolean("onlineDB", rdOnline.isChecked());
mPrefEditor.putString("benutzer", textName.getText().toString());
mPrefEditor.putString("ip", textIP.getText().toString());
mPrefEditor.apply();
finish();
}
private void loadSettings() {
textName.setText(mPrefs.getString("benutzer", ""));
textIP.setText(mPrefs.getString("ip", "192.168.0.50"));
rdOnline.setChecked(mPrefs.getBoolean("onlineDB", true));
rdOffline.setChecked(!mPrefs.getBoolean("onlineDB", true));
}
public boolean automatischLAN(){
Calendar cal = new GregorianCalendar();
Date currenttimen = new Date();
cal.setTime(currenttimen);
int freitag = cal.get(Calendar.DAY_OF_WEEK);
int STUNDE = 0;
STUNDE = cal.get(Calendar.HOUR_OF_DAY);
System.out.println(STUNDE);
if(freitag == Calendar.FRIDAY && STUNDE>11 && STUNDE< 14 ) {
System.out.println("lan");
return false;
}
else {
System.out.println("online");
return true;
}
}
public void onBackPressed()
{
saveSettings();
super.onBackPressed();
}
public void setLan(){
rdOnline.setChecked(false);
rdOffline.setChecked(true);
System.out.println("sollte lan sein");
mPrefEditor.putBoolean("onlineDB", rdOnline.isChecked());
}
}
I'm afraid my setLan() method isn't working as the values are not stored in the prefs...
What is the easieast way to check prefs and chance them on each start of the app?
Thanks for your help

You have to commit the changes in the SharedPreference.Editor variable. Replace your function above with the given one
public void setLan(){
rdOnline.setChecked(false);
rdOffline.setChecked(true);
System.out.println("sollte lan sein");
mPrefEditor.putBoolean("onlineDB", rdOnline.isChecked());
mPrefEditor.apply();
}

How do I get android preferences to work?

Sorry about this guys. This must be like the third question I've had to ask about this project alone. =(
What i want to be able to do is toggle the visibility of a radio button using a check box in a preferences activity.
There are no errors in my code and both activities run fine, but there is no change in visibility when the check box is checked or unchecked.
Here is my Activity with the radiobuttons
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioButton;
import com.medialets.android.analytics.MMAnalyticsManager;
public class Temperature extends Activity {
MMAnalyticsManager mManager;
private EditText text;
public void onStart(Bundle savedInstanceState){
super.onStart();
getPrefs();
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.temperature);
text = (EditText)findViewById(R.id.EditText01);
mManager = MMAnalyticsManager.sharedInstance(this);
mManager.start("codeHere", "1.0",
false);
}
#Override
public void onPause() {
super.onPause();
mManager.pause();
}
#Override
public void onResume() {
super.onResume();
mManager.resume();
}
#Override
public void onDestroy() {
super.onDestroy();
mManager.stop();
}
public void myClickHandler(View view){
switch (view.getId()) {
case R.id.Button01:
RadioButton celsiustokelvinButton = (RadioButton) findViewById (R.id.RadioButton05);
RadioButton celsiustofarenheitButton = (RadioButton) findViewById(R.id.RadioButton01);
RadioButton farenheittocelsiusButton = (RadioButton) findViewById(R.id.RadioButton02);
RadioButton farenheittokelvinButton = (RadioButton) findViewById(R.id.RadioButton06);
RadioButton kelvintocelsiusButton = (RadioButton) findViewById (R.id.RadioButton03);
RadioButton kelvintofarenheitButton=(RadioButton) findViewById (R.id.RadioButton04);
float inputValue = Float.parseFloat(text.getText().toString());
if (celsiustofarenheitButton.isChecked()) {
text.setText(String
.valueOf(convertCelsiusToFarenheit(inputValue)));
} if (farenheittocelsiusButton.isChecked()) {
text.setText(String
.valueOf(convertFarenheitToCelsius(inputValue)));
} if (celsiustokelvinButton.isChecked()) {
text.setText(String
.valueOf(convertCelsiusToKelvin(inputValue)));
} if (farenheittokelvinButton.isChecked()) {
text.setText(String
.valueOf(convertFarenheitToKelvin(inputValue)));
} if (kelvintocelsiusButton.isChecked()) {
text.setText(String
.valueOf(convertKelvinToCelsius(inputValue)));
} if (kelvintofarenheitButton.isChecked()) {
text.setText(String
.valueOf(convertKelvinToFarenheit(inputValue)));
}
break;
}}
private float convertFarenheitToCelsius(float fahrenheit){
return ((fahrenheit - 32) * 5 / 9);
}
private float convertCelsiusToFarenheit(float celsius){
return ((celsius * 9) / 5) + 32;
}
private double convertCelsiusToKelvin(float celsius){
return celsius + 273.15;
}
private double convertFarenheitToKelvin(float farenheit){
return ((farenheit-32)/(1.8));
}
private double convertKelvinToCelsius(float kelvin){
return kelvin-273.1;
}
private double convertKelvinToFarenheit(float kelvin){
return kelvin*1.8-459.67;
}
boolean CheckboxPreference;
private void getPrefs() {
// Get the xml/preferences.xml preferences
SharedPreferences prefs = PreferenceManager
.getDefaultSharedPreferences(getBaseContext());
CheckboxPreference = prefs.getBoolean("checkboxPref", true);
}
}
And here is my Preferences Activity
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.Preference.OnPreferenceClickListener;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.RadioButton;
import android.widget.Toast;
import android.widget.CompoundButton.OnCheckedChangeListener;
public class Preferences extends PreferenceActivity {
private RadioButton btn01;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.preferences);
btn01 = (RadioButton)findViewById(R.id.RadioButton01);
Preference customPref = (Preference) findPreference("customPref");
customPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){
public boolean onPreferenceClick(Preference preference) {
Toast.makeText(getBaseContext(),"The Custom Preference Has Been Clicked",Toast.LENGTH_LONG).show();
SharedPreferences customSharedPreference = getSharedPreferences("myCutomSharedPrefs", Activity.MODE_PRIVATE);
SharedPreferences.Editor editor = customSharedPreference.edit();
editor.putString("myCustomPref","The preference has been clicked");
editor.commit();
CheckBox();
return true;
}
private void CheckBox() {
final CheckBox ThisCheckBox = (CheckBox) findViewById (R.id.checkboxPref);
ThisCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener(){
#Override
public void onCheckedChanged(CompoundButton compoundButton,boolean test) {
if (ThisCheckBox.isChecked()){
btn01.setVisibility(View.VISIBLE);
} else {
btn01.setVisibility(View.GONE);
}
}
});
};
});
}}
Sorry there is other stuff in there as well such as an analytics plug in
Anyone have any idea as to why this just isn't working
(Just a side note. When looking at the logcat, clicking the checkbox returned no results)
EDIT: OK i've just ammended my code as suggested but i'm afraid that the preferences still do not affect anything. Anybody have any ideas?? =(

It's not working because for visiblity the values you should use are (reference):
0 = VISIBLE
4 = INVISIBLE
8 = GONE