如何在Android应用程序中存储数据

Question

I have some codes here that user can set a value using EditText in my layout. When user set number in text input and clicks on "set" button, value of EditText input, transmitted to a TextView . This is some image of that.

Here is my XML:

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Text"
        android:textSize="25sp"
        android:id="@+id/textview" />
    <EditText
        android:id="@+id/edittext"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:inputType="number"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Set"
        android:id="@+id/set" />

And java codes:

textview= (TextView)findViewById(R.id.textview);
edittext= (EditText) findViewById(R.id.edittext);
set = (Button) rootView.findViewById(R.id.set);

set.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        textview.setText(edittext.getText().toString());
    }
});

Now I want to keep value of "textview" after restarting app or device, it's matter to save all my data in internal storage.

Answer 1

You can use SharedPreferences to store simple data like that. If you need to save bigger amounts, use a database.

Answer 2

first Sqlite databse

Senad SharedPreferences

Third internet storage(SdCarc)

Answer 3

使用SharedPreferences并获取进一步的帮助来看看这个

Answer 4

Check this link if you need to know more about SharedPreferences Helper Class

http://developer.android.com/guide/topics/data/data-storage.html#pref

Answer 5

For saving of that kind of the information for you is quite nice to use SharedPreferences . This is quite easy and fast way to manage data.

To write :

SharedPreferences preferences = getSharedPreferences("prefData", Context.MODE_WORLD_WRITEABLE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("fristRow",userid.getText().toString());
editor.putString("secondRow",password.getText().toString());
editor.apply();

To Read :

SharedPreferences preferences = getSharedPreferences("prefData", Context.MODE_PRIVATE);
String Astatus = preferences.getString("fristRow", "");

Answer 6

You can use SharedPreferences for this purpose

set.setOnClickListener(new View.OnClickListener() {
                    public void onClick(View v) {
                        textview.setText(edittext.getText().toString());
                        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
                        Editor prefsEditor = prefs.edit();
                        prefsEditor.putString("text_value", edittext.getText().toString());
                        prefsEditor.commit();
                    }
                });

Inorder to read the value

SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
String textValue = prefs.getString("text_value", "");

Answer 7

To store some simple data, you can use SharedPreferences

  SharedPreferences sp = getSharedPreferences(PRE_NAME, 0);//get the preference object
  SharedPreferences.Editor editor = sp.edit();
  editor.putString("key_here", value_here);//store some value(key-->value)
  editor.commit();//commit the changes

and you can use sp.getXXXX() to get the data stored:

   SharedPreferences sp= getSharedPreferences(PREFS_NAME, 0);
   String storedValue = sp.getString("your_key", default_value);

If you want some data stored in structure, you can use SQL Lite.

Please refer to Storage Options for more details.