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POI'm not understanding the following code
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  1. POI'm not understanding the following code
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    copied!<p>I have to understand this code to create my own app(almost based on this function):</p> <pre><code>public static String[][] ReadFilePerLine(Context context, String nom) { int i = 0; try { FileInputStream fIn = context.openFileInput(nom); InputStreamReader ipsr = new InputStreamReader(fIn); BufferedReader b = new BufferedReader(ipsr); i = getLineNumber(context, nom); String[][] s = new String[2][i/2]; i = 0; String ligne; int j = 0; while ((ligne = b.readLine()) != null) { if (i % 2 == 0) s[0][j] = ligne; else { s[1][j] = ligne; j++; } i++; } fIn.close(); ipsr.close(); return s; } catch (Exception e) {} </code></pre> <p>I'm not understanding why the using of a 2D array? and with two rows ?(String[][] s = new String[2][i/2];) here is the data that it will be stored in the file:</p> <pre><code>data = date + " : " + y + "L/100KM"+ " " + value1 + "L "+ value2 + "KM\n"; </code></pre> <p>Necessary functions:</p> <pre><code> public void updatelv(Activity activity) { SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context); String fileName = getResources().getString(R.string.fileName); fileDir = "" + preferences.getString("login", "") + "."+ preferences.getString("marque", "") + "."; s = myIO.ReadFilePerLine(getApplicationContext(), fileDir+fileName); ListView L = (ListView) findViewById(R.id.lv); L.setAdapter(new ArrayAdapter&lt;String&gt;(this, R.layout.list_item, s[0])); for (int i = 0; i&lt; s[0].length; i++) { Log.d("Saves",s[0][i]); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.histo); context = getApplicationContext(); activity = this; final SharedPreferences preferences = PreferenceManager .getDefaultSharedPreferences(context); String fileName = getResources().getString(R.string.fileName); fileDir = "" + preferences.getString("login", "") + "."+ preferences.getString("marque", "") + "."; s = myIO.ReadFilePerLine(getApplicationContext(), fileDir + fileName); updatelv(this); ListView L = (ListView) findViewById(R.id.lv); L.setTextFilterEnabled(true); L.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView&lt;?&gt; parent, View view, int position, long id) { // When clicked, show a toast with the TextView text String tmp = s[1][position]; if (tmp == null) tmp = "Aucun fichier trouvé!"; Toast.makeText(getApplicationContext(), tmp, Toast.LENGTH_SHORT) .show(); } }); </code></pre> <p>ReadFilePerLine function:</p> <pre><code>public static String[][] ReadFilePerLine(Context context, String nom) { int i = 0; try { FileInputStream fIn = context.openFileInput(nom); InputStreamReader ipsr = new InputStreamReader(fIn); BufferedReader b = new BufferedReader(ipsr); i = getLineNumber(context, nom); String[][] s = new String[2][i/2]; i = 0; String ligne; int j = 0; while ((ligne = b.readLine()) != null) { if (i % 2 == 0) s[0][j] = ligne; else { s[1][j] = ligne; j++; } i++; } fIn.close(); ipsr.close(); return s; } catch (Exception e) { } </code></pre> <p>Thank you for you help.</p>
 

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