Ir al contenido principal

Android - First Step III

Get Preferences

The method help to store information we want to store even after our app has stopped, and return a SharedPreferences object.

SharedPreferences pref = getPreferences(MODE_PRIVATE);

The parameter MODE_PRIVATE means that only our app can access to the store information.


GET/SET values

Use the methods: 

pref.getString("key",default_value)
pre.setString("key", value)

Sleep the interface  

It is not recommended to use this command, because all the interface will be frozen until the established time pass.

 SystemClock.sleep(time_in_ms);
        // SystemClock.sleep(2000); // Never do this!
        // Any long-running method will slow down
        // the whole look and feel of Android and
        // make your app very unresponsive and sluggish 
Other option is use  postDelayed method, that execute a Runnable method after a specified time

private TextView mTextView;

@Override
    public void onClick(View arg0) {
               
        Runnable adder = new Runnable () {
            @Override
            public void run() {
               
                int clickCount = 20 + mPrefs.getInt("clicked", 0);
                mPrefs.edit().putInt("clicked", clickCount).putBoolean("user", true).commit();
               
                mTextView.setTextColor(0xff00ff00);
                mTextView.setText("Click!" + clickCount);
               
            }
        };
       
        // Run the adder code in 2000 milliseconds time
        // i.e. 2 seconds
        mTextView.postDelayed(adder, 2000);
       
    }
 

Comentarios

Publicar un comentario

Entradas populares de este blog

Python create package

Create a root folder Create a sub-folder "example_pkg" that contains the funtionallity packaging_tutorial/ example_pkg/ __init__.py In the root folder create the following structure  packaging_tutorial/ example_pkg/ __init__.py tests/ setup.py LICENSE README.md in the setup.py contains the configuration of the packages your package is found by find_packages() import setuptools with open ( "README.md" , "r" ) as fh : long_description = fh . read () setuptools . setup ( name = "example-pkg-YOUR-USERNAME-HERE" , # Replace with your own username version = "0.0.1" , author = "Example Author" , author_email = "author@example.com" , description = "A small example package" , long_description = long_description , long_description_content_type = "text/markdown" , url = "https://github.com/pypa/sam...
Publicar un comentario
Leer más

Rails - Basic Steps III

pValidations Validations are a type of ActiveRecord Validations are defined in our models Implement Validations Go to   root_app/app/models Open files  *.rb for each model Mandatory field validates_presence_of   :field Ex:   validates_presence_of    :title Classes The basic syntax is class MyClass        @global_variable                def my_method              @method_variable        end end Create an instance myInstance = MyClass.new Invoke a mehod mc.my_method class() method returns the type of the object In Ruby, last character of method define the behavior If ends with a question -> return a boolean value If ends with an exclamation -> change the state of the object Getter / Setter method def global_variable       return @global_variable end ...
Publicar un comentario
Leer más

Android - Basic Steps (Service)

Service Run in the main thread of the hosting application Android can kill the Service if need the resources Purpose Supporting inter-application method execution Performing background processing Start a Service Call Context.startService(Intent intent)\ To call from a Fragment use getActivity().getApplicationContext().startService( intentService); Executing the service After call startService(...)  In the Service is executed the method onStartCommand(...) If the method returns the constant START_NOT_STICKY then Android will not restart the service automatically if the the process is killedp Foreground To execute the service foreground call the method startForeground() Use this if the user is aware of the process Bind to a Service Call the method Context.bindService( Intent service ServiceConnection con int flags ) Send Toast from the Service On the method onStartCommand receive the message   ...
Publicar un comentario
Leer más