Internal Storage in Mobile Application Development.pptx

Internal Storage in Mobile Application Development

1. Internal Storage in Android Dr. Gowthami V

2. Creating an application that can write data to a file and store it in internal storage and read data from the file and display it on the main activity using TextView . Saving and loading data on the internal storage is private for an application that can not be accessed by other applications. When the app is uninstalled the data stored in the internal by that app is removed. To read and write in the android internal storage we have two methods

3. OpenFileOutput (): used for creating and saving a file. This method returns a FileOutputStream instance. Syntax:   OpenFileOutput (String filename,int mode) Parameters:   mode:   Context.MODE_PRIVATE : If the file exists then it is overridden else a new file is created.  Context.MODE_APPEND : if the file exists then the data is appended at the end of the file. Returns:   FileOutputStream  object 

4. OpenFileInput (): Used to read data from a file, this returns an FileInputStream instance. Syntax:   OpenFileInput ( String filename) Returns: FileInputStream object 

5. Example to implement this project using the Java language.

6. Step by Step Step 1: Create a New Project To create a new project in Android Studio please refer to  How to Create/Start a New Project in Android Studio .

7. Step 2: Working with the activity_main.xml file The  activity_main.xml  file has the following widgets  One  EditText  for accepting user input Two Buttons one for reading data and the other for writing One TextView to display the content of the file

8. Step 3: Working with the MainActivity.java file The file will be creating is DemoFile.txt. this can be found in  Device File Explorer > data > data > application_package > files