EditText 动态获取输入字数,限制长度

//问题最大字数
private int num = 30;

etQuestion.addTextChangedListener(new TextWatcher() {private CharSequence temp;private int selectionStart;private int selectionEnd;@Overridepublic void beforeTextChanged(CharSequence s, int start, int count, int after) {}@Overridepublic void onTextChanged(CharSequence s, int start, int before, int count) {temp = s;}@Overridepublic void afterTextChanged(Editable s) {int number = num - s.length();tvQuestionNumber.setText(number+"");selectionStart = etQuestion.getSelectionStart();selectionEnd = etQuestion.getSelectionEnd();//删除多余输入的字（不会显示出来）if (temp.length() > num) {s.delete(selectionStart - 1, selectionEnd);etQuestion.setText(s);}//设置光标在最后etQuestion.setSelection(s.length());}});