Tutorial

Android Persist Data Using Shared Preferences

Most of the projects need to persist different data in order to use it in a way or another. So in this tutorial I will show you how to persist your data using Shared Preferences in Android. First you have to know that in Android, if you need to store data you have 4 options to achieve this:

, ,
Snippets, Tutorial

Android: Open the Calculator from Android using Intent

If you make an application and you need to open the calculator that comes with Android you can use the code bellow, but be careful because some Android phones might not have the Calculator installed or the name of the package and class might differ. 1. When you make the new project call your main

, ,
Snippets, Tutorial

Android Vibrate on Click

If you want to make the phone to vibrate when you click on a button from your application: 1. You have to declare in your AndroidManifest.xml the permission: <uses-permission android:name=”android.permission.VIBRATE”/> 2. Now go to the class you want to put the vibration and in onCreate put this code: final Vibrator vibe = (Vibrator) yourActivity.this.getSystemService(Context.VIBRATOR_SERVICE); //replace

, ,
Snippets, Tutorial

Android EditText text changes Listener

If you want “listen” to the text changes from an EditText you have to use the TextWatcher. Bellow I will show you an example of TextWatcher: //first, we create an EditText EditText answer = new EditText(this); //second, we create the TextWatcher TextWatcher textWatcher = new TextWatcher() { @Override public void beforeTextChanged(CharSequence charSequence, int i, int

, ,
Tutorial

Detect when Done key is pressed

If you want to detect when a key from soft keyboard is pressed, like Done key, you can use the following code: mEditText = (EditText)findViewById(R.id.edit); mEditText.setOnEditorActionListener(new TextView.OnEditorActionListener() { @Override public boolean onEditorAction(TextView v, int actionId, KeyEvent event) { //verifies what key is pressed, in our case verifies if the DONE key is pressed if (actionId

, ,
Solutions, Tutorial

Android SSL self signed certificate pass by

This is not my work, I have just found the solution some time ago on the internetUsing the class below you can pass by the ssl certificate error that Android may throw when you are trying to connect to a self signed certified server:First the EasySSLSocketFactory class : import java.io.IOException; import java.net.Socket; import java.net.UnknownHostException; import java.security.KeyManagementException; import

, ,
Solutions, Tutorial

Android SQLite Ignore Case from Database

If you want to select data from Database and you want to ignore the case of letters you should use COLLATE NOCASE in your query: “SELECT * FROM  myDataBaseName WHERE some_column= some_value COLLATE NOCASE” It’s not exactly an android issue but you might need some day in your android projects, so I hope it helps

, , ,
Solutions, Tutorial

Run Android Lint from command line

Not many of us use android Lint tool to scan the projects for possible performance or best practices tips. Eclipse has the Lint tool included into adt plugin so Eclipse users can take advantages of this. Ok but what about developers that use intellij IDEA or other IDE for android projects? The answer is simple,

, ,
Tutorial

Android PreferenceActivity & SharedPreferences tutorial

I will start with an example. Let’s assume that we want the user to change the date format of your application. For this you must have a class that extends PreferenceActivity, but first you have to create an XML file like this: 1. Make a directory in res called “xml” 2. In the xml directory

, , ,
Scroll to Top