点击back键，报错textview的输入字符串
public class MainActivity extends ActionBarActivity {
EditText editText ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editText = (EditText) findViewById(R.id.et);
String inputtext =Loader();
if (!TextUtils.isEmpty(inputtext)) {
editText.setText(inputtext);
editText.setSelection(inputtext.length());
Toast.makeText(MainActivity.this, "restoring secceeded ....", Toast.LENGTH_SHORT).show();
}
}
//向保存的文件读取其字符串
private String Loader() {
// TODO Auto-generated method stub
FileInputStream inputStream= null;
BufferedReader reader= null;
//StringBuilder是一个类，可以用来处理字符串
StringBuilder context = new StringBuilder();
try {
inputStream = openFileInput("data");
reader = new BufferedReader(new InputStreamReader(inputStream));
String line = "";
while ((line = reader.readLine()) != null) {
//如果不为空的话，追加字符串
context.append(line);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
//释放资源，无论是否异常都是执行
try {
if (reader != null) {
reader.close();
}
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return context.toString();
}
//在退出时候保存edittext的内容
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
String outputtext = editText.getText().toString();
save(outputtext);
}
//实现的步骤
private void save(String inputtext) {
// TODO Auto-generated method stub
FileOutputStream outputStream = null;
BufferedWriter bWriter = null;
try {
outputStream = openFileOutput("data", Context.MODE_PRIVATE);
bWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
bWriter.write(inputtext);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
try {
if (bWriter != null) {
bWriter.close();
}
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
标题写错了，是保存textview的输入字符串。;P
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