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Android中EditText的輸入字數限製

在開發應用的時候,經常會限製用戶輸入的字數,比如發表評論或者其它什麼的,下麵來個簡單的demo

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EditText et_content;//定義一個文本輸入框<br>TextView tv_num;// 用來顯示剩餘字數<br>int num = 10;//限製的最大字數 <br>
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et_content = (EditText) findViewById(R.id.et_content);<br>tv_num = (TextView) findViewById(R.id.tv_num); <br>tv_num.setText("10");<br>

下麵為EditText文本框添加監聽

et_content.addTextChangedListener(new TextWatcher() {
            private CharSequence temp;
            private int selectionStart;
            private int selectionEnd;

            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                temp = s;
                System.out.println("s="+s);
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {
            }

            @Override
            public void afterTextChanged(Editable s) {
                int number = num - s.length();
                tv_num.setText("" + number);
                selectionStart = et_content.getSelectionStart();
                selectionEnd = et_content.getSelectionEnd();
                //System.out.println("start="+selectionStart+",end="+selectionEnd);
                if (temp.length() > num) {
                    s.delete(selectionStart - 1, selectionEnd);
                    int tempSelection = selectionStart;
                    et_content.setText(s);
                    et_content.setSelection(tempSelection);//設置光標在最後
                }
            }
        });


最後更新:2017-04-04 07:03:41

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