文件的储存

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1.Activity_main.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout    android:id="@+id/activity_main"    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.sh.filepersistentcetest.MainActivity">    <EditText        android:id="@+id/edit"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="type something here"        /></LinearLayout>

2.MainActivity.java

  public class MainActivity extends AppCompatActivity {    private EditText edit;//    private String data="how are you";    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        edit = (EditText)findViewById(R.id.edit);        String inputText = load();        if (!TextUtils.isEmpty(inputText))        {            edit.setText(inputText);            edit.setSelection(inputText.length());            Toast.makeText(this, "restoring sucessed", Toast.LENGTH_SHORT).show();        }    }    public String load()    {        FileInputStream in =null;        BufferedReader reader =null;        StringBuilder content = new StringBuilder();        try        {           in =openFileInput("inputText");           reader =   new BufferedReader(new InputStreamReader(in));           String line="";           while ((line=reader.readLine()) != null )           {               content.append(line);           }        }        catch (IOException e)        {            e.printStackTrace();        }        finally {              if (reader !=null)              {                  try                  { reader.close();}                  catch (IOException e)                  {e.printStackTrace();}              }        }        Toast.makeText(this,content.toString() , Toast.LENGTH_SHORT).show();        return content.toString();    }    @Override    protected void onDestroy() {        super.onDestroy();        String inputText = edit.getText().toString();        save(inputText);    }    public  void  save(String inputText)    {        BufferedWriter writer =null;        try {            //以追加的方式打开文件输出流            FileOutputStream out = openFileOutput("inputText", MODE_PRIVATE);            writer = new BufferedWriter(new OutputStreamWriter(out));            writer.write(inputText);        } catch (Exception e) {            e.printStackTrace();        }        finally {            try{                if (writer !=null)                {writer.close();                }            }            catch (IOException e)            {                e.printStackTrace();            }                }    }}

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