Recepty, články, nápady, programování. Dříve dum-zahrada, finance, internet a know-how.okhelp.cz Pro lepší výsledky hledání používejte i diakritiku.

Preferences settings save open read write application Android example

Android app setup preferences, settings, open, read, write, onStop(), onPause(), getSharedPreferences(), SharedPreferences.Editor getInt(), getBoolean(), getString() , putInt(), putString(), putBoolean() example source code.

import android.content.SharedPreferences;

public class MainClass extends Activity {
  public static final String PREFERENCES_NAME = "MyPrefsFile";
  String myNewString;
  int myNewInt;
  Boolean myNewBool;

    public void onCreate(Bundle savedInstanceState) {
        // read old settings if exist
      SharedPreferences settings = getSharedPreferences(PREFERENCES_NAME, 0);
     String sDefault = "Hello!";
      String sStringFromPrefFile = settings.getString("myString", sDefault); // new text  or default Hello!
      int nDefaultIndex = 2; //
      int nIndexFromPrefFile = settings.getInt("myInt", nDefaultIndex); // 4 or default 2
      Boolean bDefault = false;
      Boolean bFromPrefFile = settings.getBoolean("silentMode", bDefault); // true or default false
        // new settings will saved in onStop or onPause
        myNewString = "new text";
        myNewInt = 4;
        myNewBool = true;

    protected void onPause() {
        Toast.makeText(getApplicationContext(), "onPause "
        		, Toast.LENGTH_SHORT).show();

    protected void onStop() {
    /**save settings*/	
    public void savePreferences(){
    	try {
    		SharedPreferences settings = getSharedPreferences(PREFERENCES_NAME, 0);
    		SharedPreferences.Editor editor = settings.edit();
    		editor.putString("myString", myNewString);
     		editor.putInt("nMyInt", myNewInt);
    		editor.putBoolean("silentMode", myNewBool); // 
    	} catch (Exception e) {
    		// TODO Auto-generated catch block

396LW NO topic_id


Další témata ....(Topics)


RadioButton RadioGroup Java Android example | radiobutton-radiogroup-android-example

RadioButton RadioGroup Android example source code for Android developer
Example for *.xml files

       <RadioGroup android:id="@+id/idRadio_group"

            <RadioButton android:id="@+id/idRadio_1"
            <RadioButton android:id="@+id/idRadio_2"
            <RadioButton android:id="@+id/idRadio_3"


Example for *.java files

// import
import android.widget.RadioGroup;
// get handle of RadioGroup
RadioGroup  mRadioGroup = (RadioGroup) findViewById(R.id.idRadio_group);

// which RadioButton is selected for example in some function body
         int nUnits = 10; // decimetry
    	 int nIdRadio = mRadioGroup.getCheckedRadioButtonId();
    			if(nIdRadio == R.id.idRadio_1) nUnits = 1; // metr
    			else if(nIdRadio == R.id.idRadio_2) nUnits = 10; // decimetr
    			else if(nIdRadio == R.id.idRadio_3) nUnits = 100; // cm
    			else if(nIdRadio == R.id.idRadio_4) nUnits = 1000; // mm

// listener for RadioGroup Java Android example
                new RadioGroup.OnCheckedChangeListener() {
                    public void onCheckedChanged(RadioGroup group,
                            int checkedId) {
                        Log.v("Selected", "New radio item selected: " + checkedId);


ACRA allows your Android application to send Crash Reports | acra-allows-your-android-application-to-send-crash-reports

ACRA allows your Android application to send Crash Reports to various destinations:

a Google Docs spreadsheet (default and original behavior)
an email
your own server-side HTTP POST script
any other possible destination by implementing your own report sender

ACRA wiki and download page of project library

How to install mount SD card for Eclipse Android Emulator | how-install-sd-card-on-android-eclipse-emulator

If you want download some *.apk file from internet and try on your emulator you get error than you have to install SD card. You have to closing Android emulator.
Mount Android emulator SD card instruction

  1. In Eclipse go in menu Window - Android SDK and Avg Manager

  2. Select Virtual devices

  3. Select AVD Name where you need install SD card

  4. Click on Edit button

  5. In open dialog go to SD card - Size: and write 500

  6. Press button Edit AVD

  7. Run AVD emulator

Image how install SD card on Android emulator in Eclipse.