（优化）Android EditText限制输入整数和小数的位数的方法示例

最近刚做安卓，一些小笔记。
参考网上的案例，修复了小bug。

使用方法：

editText.addTextChangedListener(new DecimalInputTextWatcher(weight, 3, 2));
//限制输入位数：整数3位，小数点后2位

源码

/**
 * EditText 限制输入整数和小数 的位数
 * 默认 整数位无限制，小数位 最多2位
 */
class DecimalInputTextWatcher implements TextWatcher {

    private static final int DEFAULT_DECIMAL_DIGITS = 2;//默认 小数的位数  2 位

    private EditText editText;
    private int decimalDigits;// 小数的位数
    private int integerDigits;// 整数的位数

    public DecimalInputTextWatcher(EditText editText) {
        this.editText = editText;
        this.decimalDigits = DEFAULT_DECIMAL_DIGITS;
    }

    public DecimalInputTextWatcher(EditText editText, int decimalDigits) {
        this.editText = editText;
        if (decimalDigits <= 0)
            throw new RuntimeException("decimalDigits must > 0");
        this.decimalDigits = decimalDigits;
    }

    public DecimalInputTextWatcher(EditText editText, int integerDigits, int decimalDigits) {
        this.editText = editText;
        if (integerDigits <= 0)
            throw new RuntimeException("integerDigits must > 0");
        if (decimalDigits <= 0)
            throw new RuntimeException("decimalDigits must > 0");
        this.decimalDigits = decimalDigits;
        this.integerDigits = integerDigits;
    }

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

    }

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

    }

    @Override
    public void afterTextChanged(Editable editable) {
        String s = editable.toString();
        editText.removeTextChangedListener(this);


        if (s.contains(".")) {
            if (integerDigits > 0) {
                editText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(integerDigits + decimalDigits + 1)});
            }
            String s0 = "";
            String s1 = "";
            String [] texts = s.split("\\.");
            int currentInt = 0;
                    int currentDemical = 0;
            if (texts.length > 1) {
                currentInt = texts[0].length();
                currentDemical = texts[1].length();
                s0 = texts[0];
                s1 = texts[1];
            } else if (texts.length > 0) {
                if (s.startsWith(".")) {
                    currentDemical = texts[0].length();
                    s1 = texts[0];
                } else {
                    currentInt = texts[0].length();
                    s0 = texts[0];
                }
            } else {

            }
            s1 = s1.substring(0, Math.min(decimalDigits, currentDemical));
            s0 = s0.substring(0, Math.min(integerDigits, currentInt));
            if (!s0.isEmpty() || !s1.isEmpty()) {
                s = s0 + "." + s1;
            }

            editable.replace(0, editable.length(), s.trim());//不输入超出位数的数字
        } else {
            if (integerDigits > 0) {
                editText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(integerDigits + 1)});
                if (s.length() > integerDigits) {
                    s = s.substring(0, integerDigits);
                    editable.replace(0, editable.length(), s.trim());
                }
            }

        }
        if (s.trim().equals(".")) {//小数点开头，小数点前补0
            s = "0" + s;
            editable.replace(0, editable.length(), s.trim());
        }
        if (s.startsWith("0") && s.trim().length() > 1) {//多个0开头，只输入一个0
            if (!s.substring(1, 2).equals(".")) {
                editable.replace(0, editable.length(), "0");
            }
        }
        editText.addTextChangedListener(this);
    }
}