How can I read a text file from the SD card in Android?

In your layout you'll need something to display the text. A TextView is the obvious choice. So you'll have something like this:

<TextView     android:id="@+id/text_view"     android:layout_width="fill_parent"     android:layout_height="fill_parent"/>

And your code will look like this:

//Find the directory for the SD Card using the API//*Don't* hardcode "/sdcard"File sdcard = Environment.getExternalStorageDirectory();//Get the text fileFile file = new File(sdcard,"file.txt");//Read text from fileStringBuilder text = new StringBuilder();try {    BufferedReader br = new BufferedReader(new FileReader(file));    String line;    while ((line = br.readLine()) != null) {        text.append(line);        text.append('\n');    }    br.close();}catch (IOException e) {    //You'll need to add proper error handling here}//Find the view by its idTextView tv = (TextView)findViewById(R.id.text_view);//Set the texttv.setText(text);

This could go in the onCreate() method of your Activity, or somewhere else depending on just what it is you want to do.

In response to

Don't hardcode /sdcard/

Sometimes we HAVE TO hardcode it as in some phone models the API method returns the internal phone memory.

Known types: HTC One X and Samsung S3.

Environment.getExternalStorageDirectory().getAbsolutePath() gives a different path - Android

You should have READ_EXTERNAL_STORAGE permission for reading sdcard.Add permission in manifest.xml

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

From android 6.0 or higher, your app must ask user to grant the dangerous permissions at runtime. Please refer this linkPermissions overview

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {    if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, 0);    }}