Develop Reference

Question about CheckBox in Java in Android Studio

I am creating a project in Android Studio, in which there is a small home screen with a button. When a user clicks this button on the home screen, the application must go to another screen, which contains several checkboxes.
However, I am having two problems:
The code accesses the main page. But when you click on a button to go to another page, the application leaves the screen instead of going to another page. I already put the name of the method that is on another page, which I want you to execute, in the onclick attribute but it still doesn't work.
I would like that after a user clicks on a button that is on the home screen, opens a screen that contains several checkboxes (this screen is already made). Each check box contains a value. When a user clicks on a checkbox, I created a variable that adds up.
When the user clicks on the checkboxes the user wants, and after the user clicks the send button, the sum of the checkbox values ​​will appear in a textView.
This is the checkbox code:
int result = 0;
private CheckBox blue;
private CheckBox red;
private CheckBox yellow;
private CheckBox green;
private CheckBox black;
private CheckBox white;
private CheckBox orange;
private CheckBox purple;
private CheckBox gray;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.id.interfacegraphicalname);
blue = findViewById(R.id.blue);
red = findViewById(R.id.red);
yellow = findViewById(R.id.yellow);
green = findViewById(R.id.green);
black = findViewById(R.id.black);
white = findViewById(R.id.white);
orange = findViewById(R.id.orange);
purple = findViewById(R.id.purple);
gray = findViewById(R.id.gray);
testFinalResult(result);
}
public void check() {
if (blue.isChecked()) {
result += 30;
} else if (red.isChecked()) {
result += 30;
} else if (green.isChecked()) {
result += 30;
} else ig (yellow.isChecked()) {
result += 20;
} else if (black.isChecked()) {
result += 20;
} else if (white.isChecked()) {
result +=20;
} else if (orange.isChecked()) {
result += 10;
} else if (purple.isChecked()) {
result += 10;
} else if (gray.isChecked()) {
result +=10;
}
int testResult = check();
public void finalTestResult(int testResult) {
if (testResult <= 60) {
finalResultText.setText("low value");
} else if (testResult <= 120) {
finalResultText.setText("medium value");
} else if (testResult<= 180) {
finalResultText.setText("high value");
}
}
}
But as the code contains one more error that when you click a button on the home screen, the application is not going to the next screen for some reason, I would like to show you all the code (which is too much big to insert here on Stack OverFlow) for you to check out what is going wrong, that I'm not able to run the code normally at all, ok?
Please, could you check?
I've been working on this project for a long time, and I'm not getting the code to run normally on the smartphone.
The code link is:
https://github.com/AvaianoFC1/OficialTestProject

/Checked out your code on github here is my initial findings
hopefully it will help you resolve your issue in your Calc.java class you need to setcontentview to entries layout instead of referring back to main layout*/
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// setContentView(R.layout.activity_main);
setContentView(R.layout.entries);
you are referring back to main activity layout which only has the layout for one button, so your button is working but its taking you back to activity main - you need to display entries layout and get all your values from that layout and then move ahead accordingly
another error from my inital lookup that i noticed is this
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#android:color/holo_blue_bright"
android:onClick="sendMessage2"
android:text="OPEN PAGE 2"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.647"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.237" />
android:onClick="sendMessage2" -> you are calling the sendMessage2 function which you have not defined you need to call the openPage2 function
also you do not need the openPage1 and openPage2 in your main activity class
Let me know if this helps you these are the few errors that are flatout - also i would recommend adding a snackbar or a toast message on button click before implementing the functionality just to make sure thats its working as intended

100 Buttons and only 1 Active

I have one activity and here i have 100 buttons, i want that when i press Button 1 then press another Button the Button 1 should get unpressed.
i know i can make this with
if(Button1.isPressed()) {
Button2.setPressed(false);
Button3.setPressed(false);
Button4.setPressed(false);
Button5.setPressed(false);
Button6.setPressed(false);
Button7.setPressed(false);
Button8.setPressed(false);
......................... }
else { do nothing }
.... BUT!
it's too much code
Coders will kill me or will just laugh on me.
any ideas?
maybe there is a way to unpress the all buttons from the activity?

Not the prettiest solution ever, but you could make an OnClickListener like this:
View.OnClickListener listener = new View.OnClickListener() {
public void onClick(View v) {
ViewGroup parent = (ViewGroup) v.getParent();
for (int i = 0; i < parent.getChildCount(); i++) {
View current = parent.getChildAt(i);
if (current != v && current instanceof Button) {
((Button) current).setPressed(false);
}
}
((Button) v).setPressed(true);
}
}
and attach it to all of your buttons.
Then, whenever a button is clicked, it will iterate over all views that are in the same layout (or actually, view group) as the clicked button, and, for any of those views that are buttons except for the clicked button, it will call setPressed(false).
Note that this only works out of the box if all the buttons are in the same layout. If they are in nested layouts, you will have to adapt it a little.
Off topic: What do you need 100 buttons for? That's a lot of buttons. You may want to redesign your user interface

Ok so instead of looping through all the buttons on over and over again when one button is pressed, you can just store a variable which stores the button number of the button that was last pressed. Now, when the second button is pressed, disable the button that was pressed earlier, you get its index from the saved variable, enable the button that was pressed and store its index in the variable.
Heres an example pseudo code to give you and idea:
int buttonLastPressed = 0;
void onButtonClick(Button buttonPressed){
if(buttonLastPressed != 0){
disableButton(buttonLastPressed);
enableButton(buttonPressed);
buttonLastPressed = buttonPressed.getIndex()
}
}
Saves you from looping through each and every button to disable it.

Define id of button 1 to 100
When press button occurs save it's id in some member variable like previous_pressed
Before updating a previous_pressed value find and unpress previous pressed button like this
Button previous_pressed_button = (Button) findViewById(previous_pressed);
Now you have the previous pressed button, So upress it or whatever.

swithcing to next textview

Ok im making app and it have 15 button's and 6 textview's.I want when I press first button to change value of first textview(value is "") to something (number one for example).But problem is when i press second button if first textview is already set to some value to set set second textview to second value.
If you need something else ask in comments (sorry for bad English)
here is what I was doing(this is under onclick)when i press second button
if(textview1.equals("1")){
textview2.setText("2");}
else if (textview1.equals("")){
textview1.setText("2");
}

It sounds like you wish to show last 6 buttons pressed.
Store all pressed buttons in a List (i.e. LinkedList) of size 6. Initially, it will be empty.
Then whenever any button is pressed do two things:
1) add it to the List and delete old elements if size exceeds six.
2) set button values from List.
Second step can be achieved like this:
// all TextViews should be in a list
private List<TextView> textViews;
// declare as field
private List<String> memoryQueue = new ArrayList<String>();
public void update() {
//set fields for the pressed buttons
for (int i=0; i<6 && i<memoryQueue.size(); i++) {
String text = memoryQueue.get(i);
textViews.get(i).setText(text);
}
// set empty fields
for (int i = memoryQueue.size(); i<6; i++) {
textViews.get(i).setText("");
}
}
This code snippet assumes that you store your TextViews in a List.
And Easiest way to keep track of last six button:
public void buttonPressed(Button button) {
//get text based on your button
String text = button.getText();
if (memoryQueue.contains(text)) {
return;
}
memoryQueue.add(text);
if (memoryQueue.size() > 6) {
memoryQueue.remove(0);
}
}

Since you're concerned with the text inside of your text view, you should be using the object's getText method:
if( textview1.getText().equals("1") ){ // Edited
textview2.setText("2");
} else if (textview1.getText().equals("")){ //Edited
textview1.setText("2");
}

At first, you have to get the String text from TextView using getText() method then you can compare that String with another String. Now, change your condition as follows...
if(textview1.getText().toString().equals("1")){
textview2.setText("2");}
else if (textview1.getText().toString().equals("")){
textview1.setText("2");
}

Dynamic Buttons with two functionalities ANDROID

I have dynamic buttons that are created by a variable that can change.I want that these buttons have two functions. I did one option but I don't know how to implement the other option.
the first time I click the button I call a function that do something and the second time that I click the same button I would like to do another action. And I want to repeat this running with all the dynamic buttons created.
My code is:
LinearLayout buttonsLayout = (LinearLayout)findViewById(R.id.linearlayoutUp);
for(int i=0;i<drawView.getNumeroMallas();i++){
Button buttonMalla = new Button(this);
buttonMalla.setText("Malla "+(i+1));
buttonMalla.setId(i+1);
final int index = i;
buttonMalla.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Malla malla = drawView.getMalla(index);
drawView.paintMallaSelected(malla);
}
}
});
buttonsLayout.addView(buttonMalla);
}
}

EDIT - Very important:
I readed your code again, you could use the getTag/setTag to remember the last state of the button (i missed the for part, sorry!)
for(int i=0;i<drawView.getNumeroMallas();i++){
Button buttonMalla = new Button(this);
buttonMalla.setText("Malla "+(i+1));
buttonMalla.setId(i+1);
buttonMaila.setTag(Boolean.FALSE);
Then in setOnClickListener
if (((Boolean)v.getTag()) == Boolean.TRUE)
{
// Do first action
v.setTag(Boolean.FALSE);
}
else
{
// Do second action
v.setTag(Boolean.TRUE);
}
An idea could be to use a variable to know which was the last action.
A boolean variable
private boolean action = false;
If action is false do the first thing and set it to true. If it's true do the second action and set it to false.
It should go out any method (global of the class)
Something like
private boolean action;
buttonMalla.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
if (action == true)
{
// Do first action
}
else
{
// Do second action
}
action = !action;
Malla malla = drawView.getMalla(index);
drawView.paintMallaSelected(malla);
}
}
});
Anyway if it does something of important you should manage better the button (example button action is not based on a boolean variable but in a specific state.) time ago i builded a "select all" and "unselect all" function in an app and i checked if the user have unselect manually something to let the button act again like a "select".. I hope i gave to you an idea.
Anyway the boolean variable is the most immediate way to do it.

How to check if a button is clicked or not?

I have a Activity in android that has 4 buttons.
The first 3 buttons fetches a json data from a weather API for 1 day, next 5 days and next 10 days respectively.
I have a 4th button placed at the bottom of the screen, which takes user to second activity.
I want to restrict the entry of user to second Activity if no button from top 3 is clicked.
If the data is fetched, I mean any one of the top 3 buttons have been clicked, allow him to go to second activity on 4th button click else show a message.
How can i check on click of 4th button if any of the top 3 buttons have been clicked before?
Thanks

Put a boolean field in your activity, name it clicked and set it to false on the onCreate method of your first activity, then in the onClick method of your 3 buttons, set it to true,
and in the onClick method of your 4th button check it, if it's true go startActivity, else launch a Toast

You can make the 4th button look disable in "OnCreate" with the function "setEnabled"(may be wrong),
and then just set "setOnClickListener" for the 4th button when you click any of the others.
ps.
Can provide code example if needed.

Why don't you use if statement? You can keep the clicked count data under the first three buttons. Like this;
import java.util.stream.*;
int[] btnMemory = new int[4];
button1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
btnMemory[0] = 1;
// your code
}
});
after, you can check it with if statement under 4th button;
button4.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
int sum = IntStream.of(btnMemory).sum();
if(sum >= 3)
// your code
}
});