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Unable to use boolean values in IF statements

I have a database that is being checked using a Cursor. This database compares the data in the database to the user entered username and password. If they match data in the database a boolean is returned true. I can use a toast to output the boolean which correctly outputs as true or false if the input data does or does not match.
However, i am trying to use the boolean to move to the next activity. If the boolean is true the next intent is started. This does not work for some reason and I cant seem to work out why. Any help would be great. Thanks!
public Button btnLogin, btnSignup;
public EditText UsernameInput, PasswordInput;
public DatabaseHelper db;
public static String passUser, passPass, passFirst, passSecond;
public int count;
public Boolean matchingUser = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Align page and remove notification bar
getWindow().setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
// Define everything
btnLogin = findViewById(R.id.btnLogin);
btnSignup = findViewById(R.id.btnSignup);
UsernameInput = findViewById(R.id.UsernameInput);
PasswordInput = findViewById(R.id.PasswordInput);
db = new DatabaseHelper(this);
// validation button
btnLogin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
validateLogin(UsernameInput.getText().toString(), PasswordInput.getText().toString());
}
});
btnSignup.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
CreateUser();
}
});
}
// Validation code
public void validateLogin(String userName, String userPassword)
{
if (userName.equals("")|| userPassword.equals(""))
{
Toast.makeText(getApplicationContext(),"Fields are empty",Toast.LENGTH_SHORT).show();
}
else
{
// CHECKING USER LOGIN DETAILS
Cursor cursor = db.CompareUserData();
for (count = 0; count<=cursor.getCount();count++)
{
if (cursor.moveToPosition(count))
{
if (UsernameInput.getText().toString().equals(cursor.getString(0))&&PasswordInput.getText().toString().equals(cursor.getString(1)))
{
matchingUser = true;
}
}
Toast.makeText(this, "boolean : "+ matchingUser, Toast.LENGTH_SHORT).show();
if (matchingUser = true)
{
passUser = cursor.getString(0);
passPass = cursor.getString(1);
passFirst = cursor.getString(2);
passSecond = cursor.getString(3);
getUser();
getPass();
getFirst();
getSecond();
Toast.makeText(getApplicationContext(), "Successfully logged in", Toast.LENGTH_SHORT).show();
LoginValidation();
}
if (matchingUser = false)
{
Toast.makeText(getApplicationContext(),"Incorrect Username",Toast.LENGTH_SHORT).show();
}}
}
}
private void LoginValidation()
{
// Changing activity code
startActivity(new Intent(MainActivity.this,Login_Biometrics.class));
}
private void CreateUser()
{
// Changing activity code
startActivity(new Intent(MainActivity.this,createUser.class));
}
public static String getUser ()
{
return passUser;
}
public static String getPass ()
{
return passPass;
}
public static String getFirst ()
{
return passFirst;
}
public static String getSecond ()
{
return passSecond;
}

It wont work with one = equal sign just do:
if(matchingUser) {
// if true do something
} else {
// if false do something
}
In your case:
if (matchingUser) {
passUser = cursor.getString(0);
passPass = cursor.getString(1);
passFirst = cursor.getString(2);
passSecond = cursor.getString(3);
getUser();
getPass();
getFirst();
getSecond();
Toast.makeText(getApplicationContext(), "Successfully logged in",Toast.LENGTH_SHORT).show();
LoginValidation();
} else {
Toast.makeText(getApplicationContext(),"Incorrect Username",Toast.LENGTH_SHORT).show();
}

You have to understand some basics:
Assignment operator =
Is used to assign value to some variable.
Logical operator ==
Is used to make some logical comparison.
So instead of doing this:
if (matchingUser = true)
{
...
Do this
if (matchingUser == true)
{
...
Apply this for every condition checking in your code.

Expression calculator with square root in android

I want to calculate square root by inputing string. I try to use Math.sqrt(string) but it doesn't work. Do you have any idea how to calculate this?
I really have no idea how to use it with this library.
public class MainActivity extends ActionBarActivity {
// IDs of all the numeric buttons
private int[] numericButtons = {R.id.btnZero, R.id.btnOne, R.id.btnTwo, R.id.btnThree, R.id.btnFour, R.id.btnFive, R.id.btnSix, R.id.btnSeven, R.id.btnEight, R.id.btnNine};
// IDs of all the operator buttons
private int[] operatorButtons = {R.id.btnAdd, R.id.btnSubtract, R.id.btnMultiply, R.id.btnDivide,R.id.buttonSqr,R.id.tan,R.id.cos,
R.id.sin,R.id.open_bracket,R.id.close_bracket};
// TextView used to display the output
private EditText txtScreen;
// Represent whether the lastly pressed key is numeric or not
private boolean lastNumeric=true;
// Represent that current state is in error or not
private boolean stateError;
// If true, do not allow to add another DOT
private boolean lastDot;
private boolean firstTime = true;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Find the TextView
this.txtScreen = (EditText) findViewById(R.id.txtScreen);
// Find and set OnClickListener to numeric buttons
setNumericOnClickListener();
// Find and set OnClickListener to operator buttons, equal button and decimal point button
setOperatorOnClickListener();
}
//Find and set OnClickListener to numeric buttons.
private void setNumericOnClickListener() {
// Create a common OnClickListener
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View v) {
// Just append/set the text of clicked button
Button button = (Button) v;
if (stateError) {
// If current state is Error, replace the error message
txtScreen.setText(button.getText());
stateError = false;
} else {
// If not, already there is a valid expression so append to it
txtScreen.append(button.getText());
}
// Set the flag
lastNumeric = true;
firstTime = true;
}
};
// Assign the listener to all the numeric buttons
for (int id : numericButtons) {
findViewById(id).setOnClickListener(listener);
}
}
//Find and set OnClickListener to operator buttons, equal button and decimal point button.
private void setOperatorOnClickListener() {
// Create a common OnClickListener for operators
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View v) {
// If the current state is Error do not append the operator
// If the last input is number only, append the operator
if (lastNumeric && !stateError) {
Button button = (Button) v;
txtScreen.append(button.getText());
Log.d("dsfds",txtScreen.getText().toString());
lastNumeric = false;
lastDot = false; // Reset the DOT flag
firstTime = true;
}
}
};
// Assign the listener to all the operator buttons
for (int id : operatorButtons) {
findViewById(id).setOnClickListener(listener);
}
// Decimal point
findViewById(R.id.btnDot).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (lastNumeric && !stateError && !lastDot) {
txtScreen.append(".");
lastNumeric = false;
lastDot = true;
//firstTime = false;
}
}
});
//delete
findViewById(R.id.btndel).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (txtScreen.getText().toString().length() > 1) {
//remove string
String screen_new = txtScreen.getText().toString().substring(0, txtScreen.getText().toString().length() - 1);
txtScreen.setText(screen_new);
} else {
txtScreen.setText("");
}
lastNumeric = false;
stateError = false;
lastDot = false;
//firstTime = false;
}
});
// Clear button
findViewById(R.id.btnClear).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
txtScreen.setText(""); // Clear the screen
// Reset all the states and flags
lastNumeric = false;
stateError = false;
lastDot = false;
//firstTime = false;
}
});
// Equal button
findViewById(R.id.btnEqual).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onEqual();
}
});
}
//Logic to calculate the solution
private void onEqual() {
// If the current state is error, nothing to do.
// If the last input is a number only, solution can be found.
//if (lastNumeric && !stateError) {
if ((firstTime || lastNumeric) && !stateError){
// Read the expression
String txt = txtScreen.getText().toString();
Log.d( txt, "error");
txt = txt.replaceAll("x", "*").replaceAll("÷", "/");
// Create an Expression (A class from exp4j library)
Expression expression = new ExpressionBuilder(txt).build();
try {
// Calculate the result and display
double result = expression.evaluate();
txtScreen.setText(Double.toString(result));
lastDot = true; // Result contains a dot
} catch (ArithmeticException ex) {
// Display an error message
txtScreen.setText("Error");
stateError = true;
lastNumeric = false;
}
}
}
}

First convert your String into a number using a DecimalFormat object and it's parse function then compute your square root.
DecimalFormat df=new DecimalFormat();
sq=java.lang.Math.sqrt(df.parse(myString).doubleValue());

How to calculate reaction time?

I have developed an app that has two buttons (left and right) and a Textview that will pop up on the screen.Each button has it's corresponding word.
The user has to click the button that corresponds to TextView's word as quickly as possible when it shows. I want to calculate it's reaction time on clicking the button.
Below is my code.
public class Place_to_go_1 extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_place_to_go_1);
placeone = Global_variables.getFirst_choice_label();
placetwo = Global_variables.getSecond_choice_label();
p_one = (TextView)findViewById(R.id.p_one);
p_two = (TextView)findViewById(R.id.p_two);
btnleft = (ImageButton)findViewById(R.id.btnleft);
btnright = (ImageButton)findViewById(R.id.btnright);
next = (ImageButton)findViewById(R.id.Next);
lblmaintext = (TextView)findViewById(R.id.lblmaintext);
lblprompt = (TextView)findViewById(R.id.lblprompt);
lblreact = (TextView)findViewById(R.id.lblreact);
imgmain = (ImageView)findViewById(R.id.imgmain);
//prac = (ImageView) findViewById(R.id.prac);
Intent intent = getIntent();
final String randomId = intent.getStringExtra("Info_id");
//============ validate image if not empty
setImage_onLaunch();
//==== populate left and right choices===
populate_headers(placeone, placetwo);
//==== populate attributes=====
populate_attributes();
//============== instruction ======
setInstruction();
//=============media
wrong_press = MediaPlayer.create(this, R.raw.wrong_press);
react_fast = MediaPlayer.create(this, R.raw.react_faster);
//=== left button click trigger
btnleft.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String position = "H";
if (tanan[counter].equals(p_one.getText().toString())) {
lblprompt.setVisibility(View.INVISIBLE);
HashMap<String,String> queryValues = new HashMap<String, String>();
queryValues.put("Info_id",randomId);
queryValues.put("Choice",p_one.getText().toString());
queryValues.put("Reaction_time",String.valueOf(elapsedTime));
queryValues.put("Position",position);
queryValues.put("Main",main);
queryValues.put("Error",error);
mydb.insertTest(queryValues);
counter++;
if (counter < tanan.length) {
btnleft.setEnabled(false);
btnright.setEnabled(false);
timeStamp = System.currentTimeMillis();
//Toast.makeText(Place_to_go_1.this, ""+timeStamp, Toast.LENGTH_SHORT).show();
getreactionTime(p_one.getText().toString(), String.valueOf((((timeStamp) / 1000.0) - ((timeRun) / 1000.0))));
setIntervalTime();
} else {
//======end sa data
postEnd();
}
} else {
// Toast.makeText(Place_to_go_1.this, "Wrong pressed", Toast.LENGTH_SHORT).show();
//wrong_press.start();
wrong_click_audio();
error = "1";
lblprompt.setVisibility(View.VISIBLE);
}
}
});
//==== right button click trigger
btnright.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String position = "A";
if (tanan[counter].equals(p_two.getText().toString())) {
lblprompt.setVisibility(View.INVISIBLE);
HashMap<String,String> queryValues = new HashMap<String, String>();
queryValues.put("Info_id",randomId);
queryValues.put("Choice",p_two.getText().toString());
queryValues.put("Reaction_time", String.valueOf(elapsedTime));
queryValues.put("Position",position);
queryValues.put("Main",main);
queryValues.put("Error",error);
mydb.insertTest(queryValues);
counter++;
if (counter < tanan.length) {
btnleft.setEnabled(false);
btnright.setEnabled(false);
timeStamp = System.currentTimeMillis();
//Toast.makeText(Place_to_go_1.this, ""+timeStamp, Toast.LENGTH_SHORT).show();
getreactionTime(p_two.getText().toString(), String.valueOf((((timeStamp) / 1000.0) - ((timeRun) / 1000.0))));
setIntervalTime();
} else {
//======end sa data
postEnd();
}
} else {
// Toast.makeText(Place_to_go_1.this, "Wrong pressed", Toast.LENGTH_SHORT).show();
// wrong_press.start();
wrong_click_audio();
error = "1";
lblprompt.setVisibility(View.VISIBLE);
}
}
});
// ==== next button for the next activity (Place to go 2)
next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = getIntent();
String randomId = intent.getStringExtra("Info_id");
//============= launch activity 2 for place to go
if (instruct == true) {
next.setVisibility(View.INVISIBLE);
// prac.setVisibility(View.VISIBLE);
CountDownTimer();
} else {
//Toast.makeText(getApplication(),"Saved Successfully.",Toast.LENGTH_SHORT).show();
Intent i = new Intent(getApplicationContext(), Place_to_go_2.class);
i.putExtra("Info_id", randomId);
startActivity(i);
}
}
});
}
public void interval(){
if(counter < tanan.length){
lblmaintext.setVisibility(View.VISIBLE);
timeRun = System.currentTimeMillis();
btnleft.setEnabled(true);
btnright.setEnabled(true);
lblmaintext.setText(tanan[counter]);
setImage();
imgmain.setVisibility(View.VISIBLE);
react = true;
reacFaster();
}else{
//======end sa data
Toast.makeText(Place_to_go_1.this, "End data", Toast.LENGTH_SHORT).show();
lblmaintext.setVisibility(View.VISIBLE);
lblmaintext.setText("Ok for now");
}
}
public void setIntervalTime(){
react = false;
lblreact.setVisibility(View.INVISIBLE);
reactFaster_timer.cancel();
lblmaintext.setVisibility(View.INVISIBLE);
lblreact.setVisibility(View.INVISIBLE);
imgmain.setVisibility(View.INVISIBLE);
timer = new CountDownTimer(Global_variables.interval_time_before_choices_will_show,Global_variables.interval_time_before_choices_will_show) {
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
interval();
}
}.start();
}
int counter_countdown = 0;
int drawwable_amber = R.drawable.amber;
String arr[] = {"Ready...","Set...","Start."};
public void CountDownTimer(){
btnleft.setVisibility(View.INVISIBLE);
btnright.setVisibility(View.INVISIBLE);
lblmaintext.setBackgroundResource(0);
timer = new CountDownTimer(4000,1000) {
#Override
public void onTick(long millisUntilFinished) {
lblmaintext.setTextSize(35);
lblmaintext.setText(arr[counter_countdown]);
counter_countdown++;
}
#Override
public void onFinish() {
btnleft.setVisibility(View.VISIBLE);
btnright.setVisibility(View.VISIBLE);
lblmaintext.setBackgroundResource(drawwable_amber);
// lblmaintext.setText(tanan[counter]);
//setImage();
val_first_launch();
timeRun = System.currentTimeMillis();
react = true;
reacFaster();
}
}.start();
}
public void reacFaster(){
reactFaster_timer = new CountDownTimer(Global_variables.reaction_time_first_param,Global_variables.reaction_time_second_param) {
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
if(react == true){
//Toast.makeText(Place_to_go_1.this, "please react faster", Toast.LENGTH_SHORT).show();
react_fast.start();
lblreact.setVisibility(View.VISIBLE);
}
}
}.start();
}
public void populate_headers(String one,String two){
//== this methos sets headers as random==//
headers = new ArrayList<String>();
headers.add(one);
headers.add(two);
Collections.shuffle(headers);
p_one.setText(headers.get(0));
p_two.setText(headers.get(1));
}
public void populate_attributes(){
attributes = new ArrayList<String>();
for(int h =0;h < 5;h++){
attributes.add(placeone);
attributes.add(placetwo);
}
Collections.shuffle(attributes);
tanan = new String[attributes.size()];
for(int k = 0; k < tanan.length;k++ ){
tanan[k] = attributes.get(k);
}
}
public void postEnd(){
instruct = false;
lblprompt.setVisibility(View.INVISIBLE);
btnright.setVisibility(View.INVISIBLE);
btnleft.setVisibility(View.INVISIBLE);
next.setVisibility(View.VISIBLE);
lblmaintext.setBackgroundResource(0);
lblmaintext.setTextSize(20);
p_one.setVisibility(View.INVISIBLE);
p_two.setVisibility(View.INVISIBLE);
imgmain.setVisibility(View.INVISIBLE);
reactFaster_timer.cancel();
lblreact.setVisibility(View.INVISIBLE);
lblmaintext.setText("Well done!\nNext, is the main task. It is exactly the same as before but this time words will appear on the screen that might distract you. \nPlease respond as quickly as you can.\n Press Next to begin");
}
//=========== validate if image is enabled/ disble if not set
public void setImage_onLaunch(){
if(Global_variables.getFirst_choice_image().equals("") || Global_variables.getSecond_choice_image().equals("")){
disbaleImage();
}else{
}
}
public void setImage(){
/* if(tanan[counter].equals(p_one.getText().toString())){
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getFirst_choice_image()));
}else{
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getSecond_choice_image()));
}*/
if(placeone.equals(tanan[counter])){
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getFirst_choice_image()));
}else{
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getSecond_choice_image()));
}
}
public void val_first_launch(){
if(Global_variables.getFirst_choice_image().equals("") || Global_variables.getSecond_choice_image().equals("")){
lblmaintext.setVisibility(View.VISIBLE);
lblmaintext.setText(tanan[counter]);
}else{
imgmain.setVisibility(View.VISIBLE);
if(placeone.equals(tanan[counter])){
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getFirst_choice_image()));
}else{
imgmain.setImageBitmap(BitmapFactory.decodeFile(Global_variables.getSecond_choice_image()));
}
}
}
public void disbaleImage(){
imgmain.setBackgroundResource(0);
imgmain.setVisibility(View.GONE);
}
#Override
public void onBackPressed() {
super.onBackPressed();
startActivity(new Intent(getApplication(), MainActivity.class));
finish();
}
public String getreactionTime(String domain, String time){
// Toast.makeText(Place_to_go_1.this, time, Toast.LENGTH_SHORT).show();
//== get reaction time to every activity
Global_variables.set_timeStamps(domain, time);
return domain;
}
//===== prompt instruction====
public void setInstruction(){
btnleft.setVisibility(View.INVISIBLE);
btnright.setVisibility(View.INVISIBLE);
lblmaintext.setBackgroundResource(0);
lblmaintext.setTextSize(20);
lblmaintext.setText("Instruction:\n\nIf " + p_one.getText().toString() + " appears, press arrow left.\n If " + p_two.getText().toString() +
" appears, press arrow right.\n\nRespond as quickly as you can.");
next.setVisibility(View.VISIBLE);
}
//===== prompt instruction====
public void wrong_click_audio(){
wrong_press.start();
}
//=============end class====================
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Checks the orientation of the screen
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
// Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
} else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
//Toast.makeText(this, "portrait", Toast.LENGTH_SHORT).show();
}
}
}

Here a simple logic to calculate reaction time is to create a variable which hold a time when a question is popped up to user and the time when a user show a click reaction to question and calculate the time difference between these two action.
long timeWhenQuestionShowed = System.currentTimeMillis();
long timeWhenUserReacted = System.currentTimeMillis();
long reactionTime = timeWhenQuestionShowed - timeWhenUserReacted;

This should help:
Try using onTouch instead of onClick.
long timeBefor=0;
long timeReaction=0;
btnleft.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN: // when pressed
timeBefore=System.currentTimeMillis();
break;
case MotionEvent.ACTION_UP: // when released
timeReaction=System.currentTimeMillis() - timeBefore; // calculate difference
break;
}
}
timeReaction is your desired value.

The idea is to calculate the difference between 2 points in time. I will write 2 examples of calculating time difference in Java / measuring reaction time in Java:
System.nanoTime() or System.currentTimeMillis()
Differences are discussed here: Time measuring overhead in Java
long endTimeNanoSec = 0;
long startTimeNanoSec = System.nanoTime();
myWorkThatNeedsTiming(); // wait for user button press here
endTimeNanoSec = System.nanoTime();
long totalWorkTimeNanos = endTimeNanoSec - startTimeNanoSec;
Java StopWatch
JavaDoc: StopWatch
Stopwatch stopwatch = Stopwatch.createStarted();
myWorkThatNeedsTiming(); // wait for user button press here
stopwatch.stop();
long totalWorkTimeMillis = stopwatch.elapsedMillis();

Using setError for edit text input validation Android

I'm checking for invalid input to a group of edit texts in an alert dialog, by checking for null input and calling setError. But in my current implementation the dialog still closes even though there has been invalid input.
A boolean check has been added to each edit text to prevent the dialog from being dismissed if any of the edit texts set the boolean to false like this:
else if(TextUtils.isEmpty(strColour)) {
colourText.setError("Please enter a value");
entriesValid = false;
`
But the dialog is still dismissed despite the invalid input.
My question, whats the error here that allows the dialog to close on invalid input?
I set a break point on this line, if(entriesValid) to check if the condition is triggered but it doesn't break here meaning that the check is be skipped.
This is the complete custom dialog class:
public class MyMessageDialog {
public interface MyMessageDialogListener {
public void onClosed(String ship, String scientist, String email, String volume, String color);
}
#SuppressLint("NewApi")
public static AlertDialog displayMessage(Context context, String title, String message, final MyMessageDialogListener listener){
AlertDialog.Builder builder = new AlertDialog.Builder(context);
LayoutInflater inflater = LayoutInflater.from(context);
builder.setTitle(title);
builder.setMessage(message);
final View layoutView = inflater.inflate(R.layout.custom_view, null);
builder.setView(layoutView);
builder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
boolean entriesValid = true;
// get the edit text values here and pass them back via the listener
if(listener != null)
{
EditText shipText = (EditText)layoutView.findViewById(R.id.shipNameEditText);
EditText scientistNameText = (EditText)layoutView.findViewById(R.id.scientistEditText);
EditText scientistEmailText = (EditText)layoutView.findViewById(R.id.emailEditText);
EditText volumeText = (EditText)layoutView.findViewById(R.id.volumeEditText);
EditText colourText = (EditText)layoutView.findViewById(R.id.colourEditText);
listener.onClosed(shipText.getText().toString(),
scientistNameText.getText().toString(),
scientistEmailText.getText().toString(),
volumeText.getText().toString(),
colourText.getText().toString());
String strShipName = shipText.getText().toString();
String strScientistName = scientistNameText.getText().toString();
String strScientistEmail = scientistEmailText.getText().toString();
String strVolume = volumeText.getText().toString();
String strColour = colourText.getText().toString();
if(TextUtils.isEmpty(strShipName)) {
shipText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strShipName)) {
shipText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strScientistName)) {
scientistNameText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strScientistEmail)) {
scientistEmailText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strVolume)) {
volumeText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strColour)) {
colourText.setError("Please enter a value");
entriesValid = false;
}
}
if(entriesValid)
dialog.dismiss();
}
});
builder.show();
return builder.create();
}
}

Instead of checking listener to be null, add a try catch block. I have not tried this code. But my idea is to remove listener block with try catch and set the boolean flag accordingly. That way it becomes simple.
#SuppressLint("NewApi")
public static AlertDialog displayMessage(Context context, String title, String message, final MyMessageDialogListener listener){
AlertDialog.Builder builder = new AlertDialog.Builder(context);
LayoutInflater inflater = LayoutInflater.from(context);
builder.setTitle(title);
builder.setMessage(message);
final View layoutView = inflater.inflate(R.layout.custom_view, null);
builder.setView(layoutView);
builder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
boolean entriesValid = true;
// get the edit text values here and pass them back via the listener
try
{
EditText shipText = (EditText)layoutView.findViewById(R.id.shipNameEditText);
EditText scientistNameText = (EditText)layoutView.findViewById(R.id.scientistEditText);
EditText scientistEmailText = (EditText)layoutView.findViewById(R.id.emailEditText);
EditText volumeText = (EditText)layoutView.findViewById(R.id.volumeEditText);
EditText colourText = (EditText)layoutView.findViewById(R.id.colourEditText);
String strShipName = shipText.getText().toString();
String strScientistName = scientistNameText.getText().toString();
String strScientistEmail = scientistEmailText.getText().toString();
String strVolume = volumeText.getText().toString();
String strColour = colourText.getText().toString();
if(TextUtils.isEmpty(strShipName)) {
shipText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strShipName)) {
shipText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strScientistName)) {
scientistNameText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strScientistEmail)) {
scientistEmailText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strVolume)) {
volumeText.setError("Please enter a value");
entriesValid = false;
}
else if(TextUtils.isEmpty(strColour)) {
colourText.setError("Please enter a value");
entriesValid = false;
}
}
catch(Exception e)
{
entriesValid = false;
}
if(entriesValid)
dialog.dismiss();
}
});
builder.show();
return builder.create();
}
update - New solution - Tried and worked for me
public class Help_DialogScreen extends Dialog implements OnClickListener{
Context context;
public Help_DialogScreen(Context context) {
super(context);
// TODO Auto-generated constructor stub
this.context=context;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.help_homescreen);
EditText tvGoToAddExpense = (EditText)findViewById(R.id.txtGoToAddExpense);
Button btnTestCLick = (Button)findViewById(R.id.btnTestClick);
btnTestCLick.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(context, "Click fired", Toast.LENGTH_SHORT).show();
// I have used Toast to show that on click of button, dialog is not getting dismissed. You can add your code and do your logic here.
}
});
}
#Override
public void onClick(DialogInterface dialog, int which) {
dismiss();
}
}
In the code where you should show the dialog, add this code
Help_DialogScreen cdd=new Help_DialogScreen(CURRENTACTIVITY.this);
cdd.show();

dont go to next activity unless the entire box is fill

I made an app for my use for calculating a string of values appear in an another activity. My app has 3 editTexts and one button. If we press button calculate with the input in edit text and calculated values will displayed in a second activity. I made it successfully but my problem is if the user is leave any of the boxes empty and press the button, the system will Force Close. To avoid this I made editText in graphical layout pre entered with a hint. But if the user accidentally presses button after editing the editText again system shows a Force Close.
I tried many if else methods but it does not work. Some one show me a correct way to check all editText boxes.
public class Screen1 extends Activity {
public static StringBuilder EXTRA_MESSAGE=null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.screen1);
Button bu1= (Button)findViewById(R.id.bu);
bu1.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View message)
{ int f1,f3,f4;
String vis;
EditText t1=(EditText)findViewById(R.id.a);
EditText t3=(EditText)findViewById(R.id.c);
EditText t4=(EditText)findViewById(R.id.d);
String e1=t1.getText().toString();
String e3= t3.getText().toString();
String e4= t4.getText().toString();
f1 =Integer.parseInt(e1);
f4=Integer.parseInt(e4);
f3=Integer.parseInt(e3);
StringBuilder sb = new StringBuilder();
for( float i= (float)0.1;i<=5;i=i+(float) .1)
{
sb.append(String.format("%.1f", i)+" mcg = "+(f1*60*i*f4)/(f3*1000)+"\n");
}
vis=sb.toString();
Intent intent = new Intent(message.getContext(),Screen2.class);
intent.putExtra("EXTRA_MESSAGE",vis);
startActivity(intent);
}
});
}
}

Using [TextUtils][1] check isEmpty() text inside your onClick:
#Override
public void onCreate(Bundle savedInstanceState){
EditText t1=(EditText)findViewById(R.id.a);
EditText t3=(EditText)findViewById(R.id.c);
EditText t4=(EditText)findViewById(R.id.d);
Button bu1 = (Button) findViewById(R.id.bu);
bu1.setOnClickListener(this);
}
#Override
public void onClick(View message){
boolean foundEmpty = false;
if(TextUtils.isEmpty(t1.getText())) {
foundEmpty = true;
t1.setError("Please Enter a value");
}
if(TextUtils.isEmpty(t2.getText()){
foundEmpty = true;
t2.setError("Please Enter a value");
}
if(TextUtils.isEmpty(t3.getText()){
foundEmpty = true;
t3.setError("Please enter a value");
}
if(!foundEmpty){
/* none of your text fields are empty */
int f1, f3, f4;
f1 =Integer.parseInt(e1);
f4=Integer.parseInt(e4);
f3=Integer.parseInt(e3);
final StringBuilder sb = new StringBuilder();
for( float i= (float)0.1;i<=5;i=i+(float) .1) {
sb.append(String.format("%.1f", i)+
" mcg = "+
(f1*60*i*f4)/(f3*1000)+"\n");
}
final String vis = sb.toString();
Intent intent = new Intent(message.getContext(), Screen2.class);
intent.putExtra("EXTRA_MESSAGE", vis);
startActivity(intent);
}
}

From what I gather from your question, you're getting an error when bu1 is clicked, and at least one of the EditTexts is empty. This is because you're calling Integer.parseInt() on an empty String. The following code will check if the boxes are empty, and show a Toast if any are. It will also show a Toast if the user enters anything that's not a valid number:
public class Screen1 extends Activity
{
private static final String EXTRA_MESSAGE = "extra_msg";
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.screen1);
final EditText t1 = (EditText)findViewById(R.id.a);
final EditText t3 = (EditText)findViewById(R.id.c);
final EditText t4 = (EditText)findViewById(R.id.d);
Button bu1 = (Button)findViewById(R.id.bu);
bu1.setOnClickListener(new View.OnClickListener()
{
public void onClick(View message)
{
int f1,f3,f4;
String e1 = t1.getText().toString();
String e3 = t3.getText().toString();
String e4 = t4.getText().toString();
if (e1.equals("") || e3.equals("") || e4.equals(""))
{
Toast.makeText(Screen1.this, "Please enter all numbers.", Toast.LENGTH_SHORT).show();
return;
}
try
{
f1 = Integer.parseInt(e1);
f4 = Integer.parseInt(e4);
f3 = Integer.parseInt(e3);
StringBuilder sb = new StringBuilder();
for (float i = 0.1f; i <= 5; i = i + .1f)
{
sb.append(String.format("%.1f", i) + " mcg = " + (f1 * 60 * i * f4) / (f3 * 1000) + "\n");
}
Intent intent = new Intent(Screen1.this, Screen2.class);
intent.putExtra(EXTRA_MESSAGE, sb.toString());
startActivity(intent);
}
catch (NumberFormatException e)
{
Toast.makeText(Screen1.this, "Invalid numbers.", Toast.LENGTH_SHORT).show();
}
}
}
);
}
}