EditText 小数 长度限制

定义filter

public class DecimalInputFilter implements InputFilter {
    private final int mDecimalLength;

    public DecimalInputFilter(int decimalLength) {
        if (decimalLength < 0) {
            throw new IllegalArgumentException("decimalLength must >= 0");
        }
        mDecimalLength = decimalLength;
    }

    @Override
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
        String sourceString = source.toString();
        if (TextUtils.isEmpty(sourceString)) {
            return sourceString;
        }
        CharSequence result = source;
        String destString = dest.toString();
        if (destString.contains(".")) {
            int dotIndex = destString.indexOf(".");
            if (dstart > dotIndex) { // 新输入的内容在小数部分
                int availableDecimalLength = dotIndex + mDecimalLength + 1 - dest.length();
                if (availableDecimalLength > 0) {
                    result = source.subSequence(start, start + availableDecimalLength);
                } else {
                    result = "";
                }
            }
        }
        return result;
    }
}

使用filter

editText.setFilters(new InputFilter[]{new DecimalInputFilter(2)});