EditText 总结

1. 统计输入字数

 EditText content;//定义一个文本输入框
 TextView hasnum;// 用来显示剩余字数
 int num = 140;//限制的最大字数　　
        content = (EditText) findViewById(R.id.et_content);
 hasnumTV = (TextView) findViewById(R.id.tv_num);
 hasnumTV.setText(num+"");

 //下面为EditText文本框添加监听

 content.addTextChangedListener(new TextWatcher() {
  private CharSequence temp;
  private int selectionStart;
  private int selectionEnd;private int num = 140;
  public void beforeTextChanged(CharSequence s, int start, int count, int after) {
  }

  public void onTextChanged(CharSequence s, int start, int before, int count) {
   temp = s;
  }

  public void afterTextChanged(Editable s) {
   int number = num - s.length();
   hasnumTV.setText("" + number);
   selectionStart = content.getSelectionStart();
   selectionEnd = content.getSelectionEnd();
   if (temp.length() > num) {
    s.delete(selectionStart - 1, selectionEnd);
    int tempSelection = selectionEnd;
    content.setText(s);
    content.setSelection(tempSelection);//设置光标在最后
   }
  }
 });

避免一进入一个页面, EditText默认就会自动获取焦点。

      解决之道：在EditText的父级控件中找一个，设置成

          android:focusable="true" 
          android:focusableInTouchMode="true"

      这样，就把EditText默认的行为截断了！

3. 禁止复制和粘贴

setLongClickable(false);