Android Money Input with fixed decimal

问题:

How do you create an edittext entry that formats input in money format only? When the user enters 5, I want the input to look like "$0.05" and when they then enter 3, the input should now look like "$0.53" and finally they enter 6 and the input should look like "$5.36".

回答1:

ninjasense's complete solution basically works, but it has some issues:

1. Every time the data of the field is altered in the "onTextChanged" handler, cursor position resets to index 0 on the field, which is a bit annoying to happen when typing in monetary values.
2. It uses floats for formatting monetary values, which can backfire.

For the first problem I don't have solution yet, for the second one code like this works:

    @Override
    public void onTextChanged(CharSequence s, int start,
            int before, int count) {
        if(!s.toString().matches("^\\$(\\d{1,3}(\\,\\d{3})*|(\\d+))(\\.\\d{2})?$"))
        {
            String userInput= ""+s.toString().replaceAll("[^\\d]", "");
            StringBuilder cashAmountBuilder = new StringBuilder(userInput);

            while (cashAmountBuilder.length() > 3 && cashAmountBuilder.charAt(0) == '0') {
                cashAmountBuilder.deleteCharAt(0);
            }
            while (cashAmountBuilder.length() < 3) {
                cashAmountBuilder.insert(0, '0');
            }
            cashAmountBuilder.insert(cashAmountBuilder.length()-2, '.');
            cashAmountBuilder.insert(0, '$');

            cashAmountEdit.setText(cashAmountBuilder.toString());
        }

    }

回答2:

Building off Zds.

For keeping the cursor positioned at the end of the field use this.

cashAmountEdit.setTextKeepState(cashAmountBuilder.toString());
Selection.setSelection(cashAmountEdit.getText(), cashAmountBuilder.toString().length());

回答3:

You can use a TextWatcher to do that kind of thing.

Extend TextWatcher: http://d.android.com/reference/android/text/TextWatcher.html

public class MyTextWatcher implements TextWatcher {

    public void afterTextChanged(Editable arg0) { 

    }

    public void beforeTextChanged(CharSequence s, int start, int count, int after) { 

    }

    public void onTextChanged(CharSequence s, int start, int before, int count) {

    }

}

Then add it to your editText with

myEditText.addTextChangedListener(new MyTextWatcher());

回答4:

I found the TextWatcher to be a bit cumbersome. Instead, you can set the key listener:

setKeyListener(new CalculatorKeyListener());
// Must be called after setKeyListener(), otherwise is overridden
setRawInputType(Configuration.KEYBOARD_12KEY);

And then create a KeyListener which extends NumberKeyListener:

class CalculatorKeyListener extends NumberKeyListener {
    @Override
    public int getInputType() {
        return InputType.TYPE_CLASS_NUMBER;
    }

    @Override
    public boolean onKeyDown(View view, Editable content, int keyCode, KeyEvent event) {
        if (keyCode >= KeyEvent.KEYCODE_0 && keyCode <= KeyEvent.KEYCODE_9) {
            digitPressed(keyCode - KeyEvent.KEYCODE_0);
        } else if (keyCode == KeyEvent.KEYCODE_DEL) {                                         
            deletePressed();
        }
        return true;
    }

    @Override
    protected char[] getAcceptedChars() {
        return new char[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
    }
}

You then need to display the characters correctly, but that's not difficult; just keep track of cents, and then divide or multiply by 10, and use a NumberFormat to get the formatting correct.

回答5:

Heres my complete solution:

                tvValue.setRawInputType(Configuration.KEYBOARD_12KEY);

            tvValue.addTextChangedListener(new TextWatcher(){


                @Override
                public void afterTextChanged(Editable arg0) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void beforeTextChanged(CharSequence s, int start,
                        int count, int after) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void onTextChanged(CharSequence s, int start,
                        int before, int count) {
                    // TODO Auto-generated method stub

                    // here i converted to string
                    if(!s.toString().matches("^\\$(\\d{1,3}(\\,\\d{3})*|(\\d+))(\\.\\d{2})?$"))
                    {
                        String userInput= ""+s.toString().replaceAll("[^\\d]", "");
                        Float in=Float.parseFloat(userInput);
                        float percen = in/100;
                        tvValue.setText("$"+percen);
                    }

                }

            });

回答6:

I did this but without decimal and with dot for miles, check the code and add the functionality to support decimals.

    MyEditText.addTextChangedListener(new TextWatcher() 
        {
            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count){
                if(s.toString().length() > 0){
                    MyEditText.removeTextChangedListener(this);                 
                    String numbers = removeCharacters(s.toString());
                    int money = 0;
                    try{
                        money = Integer.parseInt(numbers);
                    }
                    catch(Exception ex){
                        money = 0;
                    }

                    MyEditText.setText(getMoney(money));
                    //Set cursor on correct position
                    int selection = start;
                    if(count > 0){
                        selection++;
                        if(MyEditText.getText().toString().length() == 2 || MyEditText.getText().toString().length() == 6 || MyEditText.getText().toString().length() == 10){
                            selection++;
                        }                           
                    }
                    else{
                        if(MyEditText.getText().toString().length() == 4 || MyEditText.getText().toString().length() == 8){
                            selection--;
                        }
                    }

                    if(selection > MyEditText.getText().toString().length()){
                        selection = MyEditText.getText().toString().length();
                    }                       

                    MyEditText.setSelection(selection);
                    MyEditText.addTextChangedListener(this);
                }
                if(s.toString().length() == 1 && count < 1 && start == 1){
                    MyEditText.removeTextChangedListener(this);
                    MyEditText.setText("");
                    MyEditText.addTextChangedListener(this);
                }

            }           

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after){

            }           

            @Override
            public void afterTextChanged(Editable s) 
            {

            }

        });



    public String removeCharacters(String money){       

    int i=0;
    while (i<money.length())
    {
        Character c = money.charAt(i);          
            if (Character.isDigit(c) && c != '.')
            {               
                i++;
            }
            else
            {               
                money = money.replace(c.toString(), "");                
            }
    }

    return money;
}


public String getMoney(int value){
    String money = "$";
    NumberFormat numberFormatter;       
    numberFormatter = NumberFormat.getNumberInstance(Locale.GERMAN);        
    money += numberFormatter.format(value);

    return money;
}

回答7:

This answer is based on Zds' answer (which in turn was based on ninjasense's answer), but this should resolve the cursor position issue:

if(!text.matches("^\\$(\\d{1,2})(\\.\\d{2})?$")) {
    int originalCursorPosition = view.getSelectionStart();
    int cursorOffset = 0;

    boolean cursorAtEnd = originalCursorPosition == text.length();

    String userInput= ""+text.replaceAll("[^\\d]", "");
    StringBuilder cashAmountBuilder = new StringBuilder(userInput);

    while (cashAmountBuilder.length() > 3 && cashAmountBuilder.charAt(0) == '0')           {  
        cashAmountBuilder.deleteCharAt(0);
        cursorOffset--;
    }
    while (cashAmountBuilder.length() < 3) {
        cashAmountBuilder.insert(0, '0');
        cursorOffset++;
    }
    cashAmountBuilder.insert(cashAmountBuilder.length() - 2, '.');
    cashAmountBuilder.insert(0, '$');

    view.setText(cashAmountBuilder.toString());
    view.setSelection(cursorAtEnd ? view.getText().length() : originalCursorPosition + cursorOffset);
}

Notes:

• The following is in a TextWatcher.onTextChanged
• I'm using a different regex than other answers, which keeps the price to < $100
• 'view' is the editText, 'text' is the string contents
• this has worked for me using an EditText with a maxLength of 6 (i.e. $00.00)