How to create a one-time welcome screen using Android preferences?

问题

I'd like to create a screen that only shows once after the application starts. Afterward, then it will only show the main screen. The way I implemented this was just to check the preferences and set the current layout based on a flag. Are there any draw backs to implementing it this way? Is there a better way?

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //Here is the main layout
        setContentView(R.layout.main);      

        mPrefs = PreferenceManager.getDefaultSharedPreferences(this);

        // second argument is the default to use if the preference can't be found
        Boolean welcomeScreenShown = mPrefs.getBoolean(welcomeScreenShownPref, false);

        if (!welcomeScreenShown) {
            //Here I set the one-time layout
            setContentView(R.layout.popup_message);             
            SharedPreferences.Editor editor = mPrefs.edit();
            editor.putBoolean(welcomeScreenShownPref, true);
            editor.commit(); // Very important to save the preference
        }
    }

回答1:

Try with Application version code. Below is an example code that I have used;

    SharedPreferences sharedPreferences = getSharedPreferences("version", 0);
    int savedVersionCode = sharedPreferences.getInt("VersionCode", 0);

    int appVershionCode = 0;

    try {
        appVershionCode = getPackageManager().getPackageInfo(getPackageName(), 0).versionCode;

    } catch (NameNotFoundException nnfe) {
        Log.w(TAG, "$ Exception caz of appVershionCode : " + nnfe);
    }   

    if(savedVersionCode == appVershionCode){
        Log.d(TAG, "$$ savedVersionCode == appVershionCode");
    }else{
        Log.d(TAG, "$$ savedVersionCode != appVershionCode");

        SharedPreferences.Editor sharedPreferencesEditor = sharedPreferences.edit();
        sharedPreferencesEditor.putInt("VersionCode", appVershionCode);
        sharedPreferencesEditor.commit();

        Builder alertDialogBuilder = new Builder(this);
        alertDialogBuilder.setTitle("Version");
        alertDialogBuilder.setMessage("This is one time show dialog box ");

        alertDialogBuilder.setNeutralButton("Close", new OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int which) {
                Log.d(TAG, "$$ onClick");

            }
        });

        alertDialogBuilder.show();
    }

回答2:

Instead of shared preference you can use below code also i have used this many times it will work perfectly it shows only one time when application start first time

public class SplashActivity extends Activity {
protected boolean _isActive = true;
protected int _splashTime = 3000; //SplashActivity will be visible for 2s
final String TAG = "SplashActivity";


public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.splash_activity);



    //a separate thread to manage splash screen
    final Thread splashThread = new Thread() {

        public void run() {

            try {
                int wait = 0;

                while (_isActive && (_splashTime > wait)) { //will show only on the first time
                    sleep(100);

                    if (_isActive) {
                        wait += 100;
                    }
                }
            } catch (InterruptedException e) {
                Log.d(TAG, e.getMessage());

            } finally {
                startActivity(new Intent(SplashActivity.this, MainActivityAbs.class));
                finish();
            }
        }
    };
    splashThread.start();
}

//if a user clicks on a back btnOrder, do not show splash screen

public boolean onTouchEvent(MotionEvent event) {
    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        _isActive = false;
    }
    return true;
}

来源：https://stackoverflow.com/questions/12398767/how-to-create-a-one-time-welcome-screen-using-android-preferences