在开发应用的时候，经常会限制用户输入的字数，比如发表评论或者其它什么的，下面来个简单的demo
EditText et_content;
//定义一个文本输入框<br>TextView tv_num;// 用来显示剩余字数<br>int num = 10;//限制的最大字数 <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>
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下面为EditText文本框添加监听
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);//设置光标在最后
}
}
});
