android EditText 限制输入大小写，大写转小写

在写登录验证的时候，需要将用户输入的大写字符转化为小写。看了下API，只有InputFilter.AllCaps是将EditText 的小写英文字符转化为大写。好吧。依赖AllCaps在写个类似的InputFilter吧。基本上Copy AllCaps的代码，只改了两行。大家看代码吧

import android.text.InputFilter;

import android.text.SpannableString;

import android.text.Spanned;

import android.text.TextUtils;

//与InputFilter.AllCaps相反

public class LowInputFilter implements InputFilter {

@Override

public CharSequence filter(CharSequence source, int start, int end,

Spanned dest, int dstart, int dend) {

for (int i = start; i < end; i++) {

if (Character.isUpperCase(source.charAt(i))) {

char[] v = new char[end - start];

TextUtils.getChars(source, start, end, v, 0);

String s = new String(v).toLowerCase();

if (source instanceof Spanned) {

SpannableString sp = new SpannableString(s);

TextUtils.copySpansFrom((Spanned) source, start, end, null,

sp, 0);

return sp;

} else {

return s;

}

}

}

return null; // keep original

}

}

android EditText 限制输入大小写，大写转小写