使用StringBuilder格式化多个EditText，而不是多次复制代码

Question

I am attempting an Email Application.

I have a stringbuilder method that is able to highlight and underline text in an EditText when the user goes to the next EditText , like in the screenshot below:

The problem is, to do the above, I have had to copy and paste the code numerous times to do this. This is the code:

edittext.setOnFocusChangeListener(new OnFocusChangeListener() {

        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (hasFocus) {
                v.setBackgroundColor(Color.WHITE);
                ((EditText) v).setTextColor(Color.BLACK);
            } else {

            /* Below highlights the email addresses after the user has entered them and moved on*/
            SpannableStringBuilder emailFormat = new SpannableStringBuilder();
            String emailFormatted = edittext.getText().toString();
            SpannableString formattedString= new SpannableString(emailFormatted); 
            formattedString.setSpan(new BackgroundColorSpan(Color.rgb(238,233,233)), 0, emailFormatted.length(), 0);
            formattedString.setSpan(new UnderlineSpan(), 0, emailFormatted.length(), 0);

            emailFormat.append(formattedString);

            edittext.setText(emailFormat, BufferType.SPANNABLE);

            }

        }
    });

I repeat the code four times as shown below (by renaming edittext as edittext2 and edittext3 and so on).

edittext2.setOnFocusChangeListener(new OnFocusChangeListener() {

        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (hasFocus) {
                v.setBackgroundColor(Color.WHITE);
                ((EditText) v).setTextColor(Color.BLACK);
            } else {

            /* Below highlights the email addresses after the user has entered them and moved on*/
            SpannableStringBuilder emailFormat = new SpannableStringBuilder();
            String emailFormatted = edittext2.getText().toString();
            SpannableString formattedString= new SpannableString(emailFormatted); 
            formattedString.setSpan(new BackgroundColorSpan(Color.rgb(238,233,233)), 0, emailFormatted.length(), 0);
            formattedString.setSpan(new UnderlineSpan(), 0, emailFormatted.length(), 0);


            emailFormat.append(formattedString);

            edittext2.setText(emailFormat, BufferType.SPANNABLE);

            }

        }
    });

The edittexts are declared in the onCreate method as shown below:

edittext = (EditText) findViewById(R.id.editText1);   // From
edittext2 = (EditText) findViewById(R.id.editText2);  // To
edittext3 = (EditText) findViewById(R.id.editText3); //  cc
edittext4 = (EditText) findViewById(R.id.editText4); //  bcc

How could I do this with less code, by reading in all the EditText in one block of code?

SOLUTION:

As suggested by @Commonwares, I created a new class Foo that implements OnFocusChangeListener :

class Foo implements OnFocusChangeListener{

    @Override
    public void onFocusChange(View v, boolean hasFocus) {
        // TODO Auto-generated method stub
        v = (EditText) v;
        if (hasFocus) {
            v.setBackgroundColor(Color.WHITE);
            ((EditText) v).setTextColor(Color.BLACK);
        } else {

            /* Below highlights the email addresses after the user has entered them and moved on*/
            SpannableStringBuilder emailFormat = new SpannableStringBuilder();
            String emailFormatted = ((EditText) v).getText().toString();
            SpannableString formattedString= new SpannableString(emailFormatted); 
            formattedString.setSpan(new BackgroundColorSpan(Color.rgb(238,233,233)), 0, emailFormatted.length(), 0);
            formattedString.setSpan(new UnderlineSpan(), 0, emailFormatted.length(), 0);

            emailFormat.append(formattedString);

            ((EditText) v).setText(emailFormat, BufferType.SPANNABLE);

        }

    }

} 

Then I can implement it in the onCreate method like this:

Foo test = new Foo();

edittext.setOnFocusChangeListener(test);
edittext2.setOnFocusChangeListener(test);
edittext3.setOnFocusChangeListener(test);
edittext4.setOnFocusChangeListener(test);

Answer 1

How could I do this with less code

Use one listener inner class rather than four.

Each time you do new OnFocusChangeListener() you are creating a separate class with separate code. Instead, create one such class ( class Foo implements OnFocusChangeListener ) with one onFocusChange() method. The widget that you need to work with is passed in as the View v parameter to onFocusChange() -- just cast that to be an EditText .