Question

I’m new in android world..

I want in my application to send an email once the user enter some sequence of numbers.. For example, if the user enter “*1234” and other numbers then he presses a button. After that directly the number will be sent using an email address

Answer 1

Don’t mind the haters on StackOverflow…here’s a super simple way to do it…use the android:onClick attribute for all of your buttons so they’d each look something like this in the layout XML (except with different tag/text):

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:onClick="checkSequence"
    android:tag="0"
    android:text="0"/>

Then define this method and these fields in your Activity:

private final String FIRST_DIGIT = "*";
private final String SECOND_DIGIT = "1";
private final String THIRD_DIGIT = "2";
private final String FOURTH_DIGIT = "3";
private int counter = 0;

public void checkSequence(View button){

    String input = button.getTag().toString();

    switch (counter){
        case 0:
            if (input.equals(FIRST_DIGIT)){
                counter++;
            }
            break;
        case 1:
            if (input.equals(SECOND_DIGIT)){
                counter++;
            }else{
                //reset the counter b/c they've screwed up the sequence
                counter = 0;
            }
            break;
        case 2:
            if (input.equals(THIRD_DIGIT)){
                counter++;
            }else{
                counter = 0;
            }
            break;
        case 3:
            if (input.equals(FOURTH_DIGIT)){
                //here you know that they've finished the sequence, so send the email
                sendEmail();
                counter = 0;
            }
            break;
    }
}

And then search StackOverflow/google for how to send an email using an Intent, and you’ll be able to write the sendEmail() method.