Multiplying an entered number in android

Question

I am working on an android app and need some help with a calculation code. A user is required to enter a value 1-5000000 into a text field (EditText), a button (calculate) is pressed, when this happens the entered number needs to be multiplied by 10% and the answer displayed on screen in a text field (EditText). Below is the code i am working on:

    public void operation(){
    if(optr.equals("*")){
        amt = Integer.parseInt(num.getText().toString());
        amt = num * 10%;
        num1.setText(Integer.toString(amt));
    }

you do not specify if you expect an integer or floating point result... — Jim, Dec 03 '15 at 14:20

score 2 · Accepted Answer · answered Dec 03 '15 at 14:04

2

Try this:

int amt = Integer.parseInt(num.getText().toString());
int result = amt/10;

Btw, you are trying to multiply your EditText and not its value in your code.

answered Dec 03 '15 at 14:04

longwalker

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Kelevandos · Answer 2 · 2015-12-03T14:13:08.123

2

Use the below code:

public void operation(){
    if(optr.equals("*")){ // what is the optr?
        amt = Integer.parseInt(num.getText().toString());
        amt *= 10%; //You must use the value here, not the EditText
        num1.setText(String.valueOf(amt));
    }
}

edited Dec 03 '15 at 14:13

answered Dec 03 '15 at 14:08

Kelevandos

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score 0 · Answer 3 · edited Dec 03 '15 at 14:07

0

Try this; % is not a percent operator in programming context.

public void operation(){
if(optr.equals("*")){
    amt = Integer.parseInt(num.getText().toString());
    amt = num / 10;
    num1.setText(Integer.toString(amt));
}
}

edited Dec 03 '15 at 14:07

Phantômaxx

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answered Dec 03 '15 at 14:06

Sameer Khan

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Thank you all for the comments. – Pooveshin Dec 03 '15 at 14:16

score 0 · Answer 4 · edited May 23 '17 at 12:16

0

You need to add a text change listener like in the answer here: android edittext onchange listener

you can also use RXJava and RXbinding to create an observable that emits the value of the edittext whenever it is changed

EDIT: nevermind didnt notice you were running this from a method

edited May 23 '17 at 12:16

Community

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answered Dec 03 '15 at 14:15

Will Evers

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score 0 · Answer 5 · answered Dec 03 '15 at 14:19

In Java you can not multiply directly with 10% to get the 10% of any number.

Changes have been made in your code by commenting your line. considering float as input.

public void operation(){
    if(optr.equals("*")){
        //amt = Integer.parseInt(num.getText().toString());
        // amt = num * 10%;
        amt = Float.parseFloat(num.getText().toString());
        amt = num/10;
        num1.setText(amt+"");

        //num1.setText(Integer.toString(amt));
    }
}

Multiplying an entered number in android

5 Answers5