/**
* 描述 ：金额输入过滤器，限制小数点后输入位数
* 默认限制小数点2位
* 默认第一位输入小数点时，转换为0.
* 如果起始位置为0,且第二位跟的不是".",则无法后续输入
* Created by Dashingl on 2019/10/26 15:30.
*/
public class MoneyValueFilter extends DigitsKeyListener {
public MoneyValueFilter() {
super(false, true);
}
// 默认2位有效数字
private int digits = 2;
public MoneyValueFilter setDigits(int d) {
digits = d;
return this;
}
@Override
public CharSequence filter(CharSequence source, int start, int end,
Spanned dest, int dstart, int dend) {
CharSequence out = super.filter(source, start, end, dest, dstart, dend);
// if changed, replace the source
if (out != null) {
source = out;
start = 0;
end = out.length();
}
int len = end - start;
// if deleting, source is empty
// and deleting can't break anything
if (len == 0) {
return source;
}
//以点开始的时候，自动在前面添加0
if (source.toString().equals(".") && dstart == 0) {
return "0.";
}
//如果起始位置为0,且第二位跟的不是".",则无法后续输入
if (!source.toString().equals(".") && dest.toString().equals("0")) {
return "";
}
int dlen = dest.length();
// Find the position of the decimal .
for (int i = 0; i < dstart; i++) {
if (dest.charAt(i) == '.') {
// being here means, that a number has
// been inserted after the dot
// check if the amount of digits is right
return (dlen - (i + 1) + len > digits) ?
"" :
new SpannableStringBuilder(source, start, end);
}
}
for (int i = start; i < end; ++i) {
if (source.charAt(i) == '.') {
// being here means, dot has been inserted
// check if the amount of digits is right
if ((dlen - dend) + (end - (i + 1)) > digits)
return "";
else
break; // return new SpannableStringBuilder(source, start, end);
}
}
// if the dot is after the inserted part,
// nothing can break
return new SpannableStringBuilder(source, start, end);
}
}
