Takes multiples attempts to close dialog box - java

I am trying to display a dialog based on the number of clicks that have occurred. I have two little issues with it which I will explain below:
So I clear the data on my app so that the number of clicks starts on 0. Basically what I am trying to do is that when I access the class below, if the number of clicks = 4, 8 or 12, then output the relevant message associated to them in my if else statements. If it doesn't equal any of those numbers then for every 4 clicks (16, 20, 24 ,28 etc) display the default message of 'You are rewarded with a video.
So starting from fresh on zero clicks, when I navigate to this page I notice for each click (1,2,3,4 etc) it displays the default dialog message which is not what I require. I want it to display the messages for 4, 8, 12 which have their own specific messages and then there after (16, 20, 24, 28 etc) should display the general message.
What I have also noticed is that if I come out of the page by selecting the back button and then access the page again, every time the dialog appears it takes me many taps on the ok button for the dialog to close. Initially before I went back from the page it only took me one tap to close the dialog but when I re-enter the page then it takes many taps and I am not sure why.
How can these 2 issues be fixed?
Code below:
import java.util.Random;
public class Content extends AppCompatActivity {
Button backButton;
Button selectAnotherButton;
TextView clickCountText;
int getClickCountInt;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_content);
final SharedPreferencesManager prefManager = SharedPreferencesManager.getInstance(Content.this);
clickCountText = findViewById(R.id.click_count);
clickCountText.setText(Integer.toString(prefManager.getClicks()));
getClickCountInt = Integer.parseInt(clickCountText.getText().toString());
backButton = findViewById(R.id.button_back);
selectAnotherButton = findViewById(R.id.button_select_another);
setContent();
selectAnotherButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
clickCountText.setText(Integer.toString(prefManager.increaseClickCount()));
if (getClickCountInt == 4){
ShowRewardDialog("You are rewarded with a the yellow smiley face in the homepage");
} else if (getClickCountInt == 8) {
ShowRewardDialog("You are rewarded with a the green smiley face in the homepage");
} else if (getClickCountInt == 12) {
ShowRewardDialog("You are rewarded with a the red smiley face in the homepage");
} else {
for(int i = 0; i <= getClickCountInt; i+=4) {
ShowRewardDialog("You are rewarded with a video\"");
}
}
setContent();
}
});
backButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
finish();
}
});
}
private void ShowRewardDialog(String message) {
final Dialog dialog = new Dialog(Content.this);
dialog.setContentView(R.layout.custom_dialog);
SpannableString title = new SpannableString("YOU GAINED A REWARD");
title.setSpan(new ForegroundColorSpan(Content.this.getResources().getColor(R.color.purple))
, 0, title.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
// set the custom dialog components - text, image and button
TextView text = dialog.findViewById(R.id.dialog_text);
dialog.setTitle(title);
text.setText(message);
Button dialogButton = dialog.findViewById(R.id.dialog_button_OK);
// if button is clicked, close the custom dialog
dialogButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
dialog.show();
}
}
UPDATE
Ok to make it easier I will say what is the current problem and how I want it to work.
I have disabled the else statement for now in the Content class where it displays a generic message in the dialog box.
Ok so I have created a class for my Shared Preferences and I can get an instance of it from both the MainActivity class (this is my homepage) and Content class (this is second page).
Lets say the click counts starts on 0 (and I display this as a text) and I am on the homepage. When I select the jokes button from the homepage, I will navigate to the second page and the count starts at 1. If I select 'Select Another' button which is displayed in second page, then the count goes to 2 (as I can see by the text displayed), click again then three and click again it will go to 4 and the dialog box for count 4 is displayed. This works for when I go to 8 and 12 as well.
When I select the 'Back' button to go from second page to front page, I can see the count remains the same as the count displayed in the second page. E.g if count was set to 8 on page 2 and I click back, the homepage displays the count of 8 as well when I view the text.
This seems all well and good. However lets start again from 0. If I click on the jokes button then I am on 1, I select 'Select Another' button twice so the count is on 3 and then click back button. Count is currently on 3 when I view the homepage. If I click on the jokes button again then the count is on 4 which is correct, however the dialog for if count equals to 4 does not appear. However if I click on the 'Select Another' button 3 more times then it will display the dialog for 4. So it seems like the dialog will only appear for 4 if the 'Select Another' button is clicked four in a row, rather than how I want it which is if the total number of clicks count equals 4 then show the dialog.
What will I need to do to fix this?
Below is the code:
SharedPreferencesManager class:
public class SharedPreferencesManager{
private static final String APP_PREFS = "AppPrefsFile";
private static final String NUMBER_OF_CLICKS = "numberOfClicks";
private SharedPreferences sharedPrefs;
private static SharedPreferencesManager instance;
private SharedPreferencesManager(Context context) {
sharedPrefs = context.getApplicationContext().getSharedPreferences(APP_PREFS, MODE_PRIVATE);
}
public static synchronized SharedPreferencesManager getInstance(Context context){
if(instance == null)
instance = new SharedPreferencesManager(context);
return instance;
}
public int increaseClickCount() {
int clickCount = sharedPrefs.getInt(NUMBER_OF_CLICKS, 0);
clickCount++;
SharedPreferences.Editor editor = sharedPrefs.edit();
editor.putInt(NUMBER_OF_CLICKS, clickCount);
editor.apply();
return clickCount;
}
public int getClicks(){
return sharedPrefs.getInt(NUMBER_OF_CLICKS, 0);
}
}
MainActivity class (page 1)
public class MainActivity extends AppCompatActivity {
SharedPreferencesManager prefManager = SharedPreferencesManager.getInstance(this);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button jokesButton = findViewById(R.id.button_jokes);;
jokesButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
prefManager.increaseClickCount();
openContentPage("jokes");
}
});
TextView clickCountText = findViewById(R.id.click_count);
clickCountText.setText(Integer.toString(prefManager.increaseClickCount()));
}
private void openContentPage(String v) {
Intent intentContentPage = new Intent(MainActivity.this, Content.class);
intentContentPage.putExtra("keyPage", v);
startActivity(intentContentPage);
}
}
Content class (page 2):
public class Content extends AppCompatActivity {
Button backButton;
Button selectAnotherButton;
TextView clickCountText;
int getClickCountInt;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_content);
final SharedPreferencesManager prefManager = SharedPreferencesManager.getInstance(Content.this);
clickCountText = findViewById(R.id.click_count);
clickCountText.setText(Integer.toString(prefManager.getClicks()));
getClickCountInt = Integer.parseInt(clickCountText.getText().toString());
backButton = findViewById(R.id.button_back);
selectAnotherButton = findViewById(R.id.button_select_another);
setContent();
selectAnotherButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
getClickCountInt++;
clickCountText.setText(Integer.toString(prefManager.increaseClickCount()));
if (getClickCountInt == 4){
ShowRewardDialog("You are rewarded with a the yellow smiley face in the homepage");
} else if (getClickCountInt == 8) {
ShowRewardDialog("You are rewarded with a the green smiley face in the homepage");
} else if (getClickCountInt == 12) {
ShowRewardDialog("You are rewarded with a the red smiley face in the homepage");
} //else {
//for(int i = 0; i <= getClickCountInt; i+=4) {
//ShowRewardDialog("You are rewarded with a video\"");
//}
//}
}
});
backButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
finish();
}
});
}
private void ShowRewardDialog(String message) {
final Dialog dialog = new Dialog(Content.this);
dialog.setContentView(R.layout.custom_dialog);
SpannableString title = new SpannableString("YOU GAINED A REWARD");
title.setSpan(new ForegroundColorSpan(Content.this.getResources().getColor(R.color.purple))
, 0, title.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
// set the custom dialog components - text, image and button
TextView text = dialog.findViewById(R.id.dialog_text);
dialog.setTitle(title);
text.setText(message);
Button dialogButton = dialog.findViewById(R.id.dialog_button_OK);
// if button is clicked, close the custom dialog
dialogButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
dialog.show();
}
}

The first problem with your algorithm is that you're not adding the current clicks to your click count.
Inside the onClick of selectAnotherButton.setOnClickListener you should add a getClickCountInt++ (and dont forget to update clickCountText with this new value).
Also, on your onCreate you should get the value for getClickCountInt from SharedPreferences, and then use it to set the value on clickCountText, not the other way around.
This answear shows how to read/store data in SharedPreferences.

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Plus/Minus button with a counter but counter does not work properly

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This is the adapter class where the ImageButtons and TextView listeners are implemented
#NonNull
#Override
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Snackbar.make(view,"Cannot have < 0 QTY",Snackbar.LENGTH_SHORT).setAction("RETRY", new View.OnClickListener() {
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}[![enter image description here][1]][1]
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(Note***) I tried checking the counter using getter and setter to check whether it worked and it did so I have no idea why when pressing "+" after "-" it wouldn't just +1 from the value after "-" button.
try putting
int count = Integer.parseInt(model.getQuantity());
inside onClick for plusbutton onclicklistener

Reset Button to default background

I know that was already asked but it is outdated:
I have 2 buttons that represent 2 choices and if one is selected the background color gets changed to yellow. But if i want to change the choice i need to somehow reset the button:
I already try to set it back but some old design comes out. Can you provide me the id of the modern button style? And show me how to implement it?
int myChoice;
if (view == findViewById(R.id.choice1)){
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Use Tags with getBackground(). This will assure you are always setting back to original.
Add following in beginning of function
if (v.getTag() == null)
v.setTag(v.getBackground());
Then instead of setBackgroundResource, use
v.setBackground(v.getTag());
Starting from here, you can store the default color of the button into a Drawable and grab the selection color (Yellow in your case) into anther Drawable, then toggle background colors of buttons with these Drawable variables
please check below demo
public class MainActivity extends AppCompatActivity {
private Drawable mDefaultButtonColor;
private Drawable mSelectedButtonColor;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button btn1 = findViewById(R.id.btn1);
final Button btn2 = findViewById(R.id.btn2);
mDefaultButtonColor = (btn1.getBackground());
mSelectedButtonColor = ContextCompat.getDrawable(this, R.color.buttonSelected);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
toggleButton(btn1, true);
toggleButton(btn2, false);
}
});
btn2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
toggleButton(btn1, false);
toggleButton(btn2, true);
}
});
}
private void toggleButton(Button button, boolean isSelected) {
button.setBackground(isSelected ? mSelectedButtonColor : mDefaultButtonColor);
}
}

NullPointerException setting onClickEvent for dynamic button [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
I have a function which creates a button, which has an onClick event to bring up a custom dialog which just shows some information from the functions parameters. The dialog has two buttons on it as well, one to close the dialog, and one to add information to a file.
When I try to set onClick events for those buttons, the app crashes, and the error I get is a NullPointerException which says that I am trying to invoke a virtual method on a null object reference.
If I comment out the part where I set the onClickEventListener code for both buttons, then the dialog appears as normal, with the buttons on it.
Note: context is a variable declared in the class. It is simply Context context = this
Code is below:
public void addButton(String text, int id, String areas, String details, String notes) {
Button button = new Button(this);
final String title = "Add "+text;
final String dName = text;
final String dAreas = areas;
final String dDetails = details;
final String dNotes = notes;
button.setText(text);
button.setTextColor(ContextCompat.getColor(context, R.color.buttonText));
button.setTextSize(32);
button.setId(id);
if (isEven(id+1)) {
button.setBackgroundResource(R.drawable.buttonshapeother);
} else {
button.setBackgroundResource(R.drawable.buttonshape);
}
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// Make custom dialog
final Dialog dialog = new Dialog(context);
Button add = (Button) dialog.findViewById(R.id.btnAddExer);
Button cancel = (Button) dialog.findViewById(R.id.btnCancel);
dialog.setContentView(R.layout.popup_exercise);
dialog.setTitle(title);
// Set the custom components now
TextView tName = (TextView) dialog.findViewById(R.id.lblNameData);
TextView tAreas = (TextView) dialog.findViewById(R.id.lblAreaData);
TextView tDetails = (TextView) dialog.findViewById(R.id.lblDetailsData);
TextView tNotes = (TextView) dialog.findViewById(R.id.lblNotesData);
tName.setText(dName);
tAreas.setText(dAreas);
tDetails.setText(dDetails);
tNotes.setText(dNotes);
// Add functions to buttons
add.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (addExercise(dName, dAreas, dDetails, dNotes)) { // Add exercise to user's workout
Toast.makeText(context, "Exercise was added to your workout", Toast.LENGTH_LONG).show();
dialog.dismiss(); // Close dialog
} else {
Toast.makeText(context, "There was an error adding your exercise", Toast.LENGTH_LONG).show();
}
}
});
cancel.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
dialog.dismiss(); // Close dialog
}
});
dialog.show(); // Actually show the dialog
}
});
LinearLayout lay = (LinearLayout) findViewById(R.id.innerLay);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
lay.addView(button, params);
}
public boolean isEven(int num) {
if ((num&1) == 0) {
return true;
} else {
return false;
}
}
Because you are trying to find button view before setting the layout to it. So try like this:
final Dialog dialog = new Dialog(context);
dialog.setContentView(R.layout.popup_exercise);
dialog.setTitle(title);
Button add = (Button) dialog.findViewById(R.id.btnAddExer);
Button cancel = (Button) dialog.findViewById(R.id.btnCancel);

How should I return to a previous dialog from another one?

I've got an inputDialog, which allows for some text inputs. On clicking save, the inputDialog checks if the entered text is already available (to prevent double entries). If this is the case, a new AlertDialog is created, simply stating "The value you entered already exists", with just an "Ok" button to dismiss this AlertDialog. This all works.
I would like to have the inputDialog pop back up again, after dismissing the AlertDialog, with the values that were entered by the user before still in the editText fields.
I'm not expecting any problems on getting those values back in the editText fields (Store them in a variable on clicking save, if the double entry error occurs, set those variables on the editText's. If I'm doing this in a stupid way, please let me know).
I am however having trouble with getting the first (inputDialog) dialog to come back. The code you see below is the code for my inputDialog fragment (The code is simplified, so if something seems to be missing, it probably is. Let me know, so I can add it back in.)
So, to repeat myself: How can I return to the previous dialog after dismissing the second one?
StuffManagerInputDialogFragment.java:
public class StuffManagerInputDialogFragment extends DialogFragment {
EditText nameInputField;
EditText tagInputField;
DBHandler dbHandler;
StuffManagerFragment f = new StuffManagerFragment();
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
LayoutInflater inflater = getActivity().getLayoutInflater();
final View v_iew = inflater.inflate(R.layout.fragment_inputdialog, null);
nameInputField = (EditText) v_iew.findViewById(R.id.inputdialogname);
tagInputField = (EditText) v_iew.findViewById(R.id.inputdialogtag);
dbHandler = new DBHandler(getActivity(), null, null, 1);
final MainActivity ma = (MainActivity) getActivity();
final AlertDialog.Builder newLinkDialog = new AlertDialog.Builder(getActivity());
newLinkDialog.setView(v_iew)
.setTitle("New Link")
.setPositiveButton("Save", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
String nameInputFieldText = nameInputField.getText().toString();
String tagInputFieldText = tagInputField.getText().toString();
ArrayList<String> nameArray = dbHandler.nameArrayMethod();
ArrayList<String> tagArray = dbHandler.tagArrayMethod();
NavigationView navigationView = (NavigationView) getActivity().findViewById(R.id.nav_view);
Menu menu = navigationView.getMenu();
if (nameArray.contains(nameInputFieldText) || tagArray.contains(tagInputFieldText)) {
if (nameArray.contains(nameInputFieldText) && tagArray.contains(tagInputFieldText)) {
AlertDialog.Builder errorBoth = new AlertDialog.Builder(getActivity())
.setTitle("Error")
.setMessage("The name and tag you entered are already in use.")
.setIcon(R.drawable.ic_error_black)
.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
//Return to previous dialog here
}
});
errorBoth.show();
}
} else {
dbHandler.addLink(nameInputFieldText, tagInputFieldText);
nameArray = dbHandler.nameArrayMethod();
int nameArraySize = (nameArray.size() - 1);
MenuItem item = menu.add(R.id.group1, nameArraySize, 1, nameArray.get(nameArraySize));
Toast.makeText(getContext(), "'" + nameInputFieldText + " - " + tagInputFieldText + "' link saved.", Toast.LENGTH_SHORT).show();
ma.addSMVFFragments();
f.hideDeleteAllButton = false;
getActivity().invalidateOptionsMenu();
}
}
})
.setNegativeButton("Cancel", null);
return newLinkDialog.create();
}
}
A better solution is to have a dialog fragment for your input layout, and that dialog fragment would display an AlertDialog on OK if the text validation fails. The input dialog fragment would not dismiss in this case, it will remain in the background so when you dismiss the alert dialog to tell the user the input is invalid, you return to the input dialog as it was.
To prevent the dialog fragment from dismissing on OK you would override onStart and get a reference to the OK button and set the listener there, like this:
#Override
public void onStart() {
super.onStart();
AlertDialog alertDialog = (AlertDialog) getDialog();
if (alertDialog != null) {
mOKButton = alertDialog.getButton(AlertDialog.BUTTON_POSITIVE);
mOkButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (field OK) {
// save data
dismiss();
} else {
// show error dialog
}
}
});
}
}

android java calling button from XML without getting NULL

I'm looking to call a few buttons but seem to be getting a NULL when trying to findbyviewid. When I activate this activity, it crashes.
//CREATE INSTANCE OF GLOBAL - QUESTIONS/ANSWERS
Global global = Global.getInstance();
//CURRENT QUESTION
static int QQ = 0;
//CORRECT ANSWER COUNT
static int correctAnswers = 0;
//CREATE VARIABLE FOR TEXTVIEW/QUESTION
TextView textQuestion = (TextView) findViewById(R.id.textQuestion);
//CREATE VARIABLES FOR BUTTONS/ANSWERS
Button buttonOne = (Button) findViewById(R.id.answerOne);
Button buttonTwo = (Button) findViewById(R.id.answerTwo);
Button buttonThree = (Button) findViewById(R.id.answerThree);
Button buttonFour = (Button) findViewById(R.id.answerFour);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_practice_questions);
setButtons();
buttonOne.setOnClickListener(this);
buttonTwo.setOnClickListener(this);
buttonThree.setOnClickListener(this);
buttonFour.setOnClickListener(this);
}
public void setButtons()
{
//SET QUESTION STRING TO TEXTVIEW
textQuestion.setText(global.getQ(QQ));
//SET ANSWER STRINGS TO BUTTONS' TEXT
buttonOne.setText(global.getA(QQ, 0));
buttonTwo.setText(global.getA(QQ, 1));
buttonThree.setText(global.getA(QQ, 2));
buttonFour.setText(global.getA(QQ, 3));
}
#Override
public void onClick(View v)
{
switch(v.getId())
{
case R.id.answerOne:
checkAnswer(0, buttonOne);
break;
case R.id.answerTwo:
checkAnswer(1, buttonTwo);
break;
case R.id.answerThree:
checkAnswer(2, buttonThree);
break;
case R.id.answerFour:
checkAnswer(3, buttonFour);
break;
default:
break;
}
}
public void checkAnswer(int a, Button b){
//IF AN INCORRECT ANSWER WAS CHOSEN, MAKE THE BACKGROUND RED
if(!global.getS(QQ, a))
{
b.setBackgroundColor(Color.RED);
}
else
{
//INCREMENT THE CORRECT ANSWER COUNTER
correctAnswers++;
}
//SET BACKGROUND OF CORRECT BUTTON TO GREEN
if(global.getS(QQ, 0))
{
buttonOne.setBackgroundColor(Color.GREEN);
}
else if(global.getS(QQ, 1))
{
buttonTwo.setBackgroundColor(Color.GREEN);
}
else if(global.getS(QQ, 2))
{
buttonThree.setBackgroundColor(Color.GREEN);
}
else if(global.getS(QQ, 3))
{
buttonFour.setBackgroundColor(Color.GREEN);
}
else
{
//IF NO ANSWER IS CORRECT, SET ALL TO BLUE
buttonOne.setBackgroundColor(Color.BLUE);
buttonTwo.setBackgroundColor(Color.BLUE);
buttonThree.setBackgroundColor(Color.BLUE);
buttonFour.setBackgroundColor(Color.BLUE);
}
//MOVE TO NEXT QUESTION
}
I have 4 buttons in the XML file and want to be able to set the text to them, as well as run a listener for the set of buttons (answers to a question). When one of the buttons is clicked, it should determine if it's the correct answer by pulling the status (true/false) and highlighting it red if it's incorrect. It then highlights the correct answer green.
At least, some of this is in theory and I'm trying to test it out, but I can't start the activity without crashing.
I'm not 100% sure but I think you can't do the findViewById at the instance constructions. You need to those inside onCreate() (after you called setContentView)
Just how i said in comment, you should initialize it in OnCreate method, cause you set view layout for activity here. And before you do it, all findViewById returns null.
So, here your code:
Button buttonOne;
Button buttonTwo;
Button buttonThree;
Button buttonFour;
TextView textQuestion;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_practice_questions);
buttonOne = (Button) findViewById(R.id.answerOne);
buttonTwo = (Button) findViewById(R.id.answerTwo);
buttonThree = (Button) findViewById(R.id.answerThree);
buttonFour = (Button) findViewById(R.id.answerFour);
textQuestion = (TextView) findViewById(R.id.textQuestion);
[...]
}

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