CODEWITHSUNDEEP
androidonclickandroid-edittextonclicklistener
mr nooby noob
mr nooby noob

Reputation: 2253

How to display values on edit text when the user presses a button?

I am trying to make a calculator app that displays everything the user clicks on the edit text screen, however, when the user clicks a button, the edit text screen still remains blank. I have put some print statements to see what happens and this is what I have found out:

The print statement in updateEditText() is always blank, even if the user clicks a button, yet the print statement in getValuesPressed() successfully prints out where buttons were clicked.

I do not understand what I'm doing wrong.

Here is what I have:

    void updateEditText(){
    EditText et = (EditText) findViewById(R.id.editText);
    System.out.println("THE VALUE PRESSED IS: " + getValuesPressed());
    et.setText(getValuesPressed());//problem here
}

//return and concat the buttons that were clicked
String getValuesPressed(){

    for(int i = 0; i < buttonList.length; i++){

        final int j = i;
        buttonList[i].setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                System.out.println("THE BUTTON WAS PRESSED: " + buttonList[j].getText());
                switch(j){

                    case 0://CLEAR
                        textOnScreen = "0";
                        break;

                    case 5://SQRT
                        solveEquation();
                        //CASE: IF IT IS NEG U CANT TAKE THE SQRT!!!!
                        textOnScreen = String.valueOf(Math.sqrt(Double.parseDouble(textOnScreen)));
                        break;

                    case 18: //NEGATIVE
                        if(textOnScreen.charAt(textOnScreen.length() - 1) != '-')
                            textOnScreen = textOnScreen + "-";
                        else
                            textOnScreen = textOnScreen.substring(0, textOnScreen.length() - 1);
                        break;

                    case 19: //BACKSPACE
                        if(textOnScreen.length() == 1)
                            textOnScreen = "0";
                        else
                            textOnScreen = textOnScreen.substring(0, textOnScreen.length() - 1);
                        break;

                    case 20: //SOLVE
                        solveEquation();
                        break;

                    default://concat all of the other buttons pressed
                        textOnScreen = textOnScreen + buttonList[j].getText();
                        break;
                }
            }
        });
    }
    return textOnScreen;
}

Upvotes: 1

Views: 1142

Answers (2)

Fabian
Fabian

Reputation: 237

Your whole code doesn't really make sense to me. The first thing you should do is to add an onClickListener to all your buttons. This listener could look something like this:

@Override
        public void onClick(View v) {

            System.out.println("THE BUTTON WAS PRESSED: " + ((Button)v).getText();
            switch(v.getId()){

                case R.id.<ID of this Button>://CLEAR
                    et.setText("0");
                    break;

                case R.id.<ID of this Button>://SQRT
                    solveEquation();
                    //CASE: IF IT IS NEG U CANT TAKE THE SQRT!!!!
                    et.setText(String.valueOf(Math.sqrt(Double.parseDouble(textOnScreen))));
                    break;

                case R.id.<ID of this Button>: //NEGATIVE
                    if(et.getText().charAt(et.getText().length() - 1) != '-')
                        et.setText(et.getText + "-");
                    else
                        et.setText(et.getText().toString().substring(0, et.getText().length() - 1));
                    break;

                case R.id.<ID of this Button>: //BACKSPACE
                    if(et.getText().length() == 1)
                        et.setText("0");
                    else
                        et.setText(et.getText().toString()substring(0, et.getText().length() - 1));
                    break;

                case R.id.<ID of this Button>: //SOLVE
                    solveEquation();
                    break;
            }
        }

Upvotes: 1

Elyakim Levi
Elyakim Levi

Reputation: 370

You are not supposed to set the OnClickListener more than once for each button. Change the String getValuesPressed() function to void setButtonClickEvents().

Also, you don't need the updateEditText() function. Instead of concatenating the textOnScreen, concatenate the EditText directly:

case 0://CLEAR
    et.setText("0");
    break;

case 5://SQRT
    solveEquation();
    //CASE: IF IT IS NEG U CANT TAKE THE SQRT!!!!
    et.setText(String.valueOf(Math.sqrt(Double.parseDouble(et.getText().toString())));
    break;

and so on.

Upvotes: 2

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