需求是，在EditText中輸入數字，而且數字範圍在0到100。貼出程式碼如下：

        edit.addTextChangedListener(new TextWatcher(){
            int l=0;////////記錄字串被刪除字元之前，字串的長度
            int location=0;//記錄游標的位置

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

                l=s.length();
                location=edit.getSelectionStart();
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                // TODO Auto-generated method stub
                Pattern p = Pattern.compile("^(100|[1-9]\\d|\\d)$"
 
);

                Matcher m =p.matcher(s.toString());
                if(m.find() || ("").equals(s.toString())){
                    System.out.print("OK!");
                }else{
                    System.out.print("False!");
                    Toast.makeText(context, "請輸入正確的數值", Toast.LENGTH_SHORT).show();
                }
            }

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

            }});

xml中新增

android:inputType="number"