我的SharedPreferences值由于某种原因未通过

Question

So I've created three classes :

1) Splash Screen Class 2) Intro Class 3) Main Activity Class

My intention is, after the splash screen, if the app has been launched for the first time, it is supposed to show the intro activity which works fine.

In intro activity, I have added terms and conditions checkbox which will start the app only if it is checked which also works fine.

The issue is, Splash Screen - Each time the app is launched, my app will check if it is the first time or if it isn't the first time, then it will check if the user has agreed to the terms and if both are passed, start the main activity.

I'm using SharedPreferences for this but it isn't working as I expected it to, so need your help!

Here's the code for SplashActivity

public class SplashActivity extends AppCompatActivity {

    private static final int SPLASH_DELAY = 200;

    private final Handler mHandler   = new Handler();
    private final Launcher mLauncher = new Launcher();

    @Override
    protected void onStart() {
        super.onStart();

        mHandler.postDelayed(mLauncher, SPLASH_DELAY);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
       // setContentView(R.layout.activity_splash);
    }

    @Override
    protected void onStop() {
        mHandler.removeCallbacks(mLauncher);
        super.onStop();
    }

    private void launch() {
        if (!isFinishing()) {

            SharedPreferences settings=getSharedPreferences("prefs",0);
            boolean firstRun=settings.getBoolean("firstRun",false);

            if(!firstRun)
            {
                SharedPreferences.Editor editor=settings.edit();
                editor.putBoolean("firstRun",true).apply();
                editor.commit();
                Intent i=new Intent(SplashActivity.this, IntroActivity.class);
                overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
                startActivity(i);
                finish();
            }
            else
            {
                SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
                String name=preferences.getString("Policy","Disagreed");
                if(!name.equals("Agreed"))
                {
                    Intent a=new Intent(SplashActivity.this, MainActivity.class);
                    overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
                    startActivity(a);
                    finish();
                } else
                {
                    Intent i=new Intent(SplashActivity.this, IntroActivity.class);
                    overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
                    startActivity(i);
                    finish();
                }

            }
        }

    }

    private class Launcher implements Runnable {
        @Override
        public void run() {
            launch();
        }
    }
}

IntroActivity :

public class IntroActivity extends MaterialIntroActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        enableLastSlideAlphaExitTransition(true);

        getBackButtonTranslationWrapper()
                .setEnterTranslation(new IViewTranslation() {
                    @Override
                    public void translate(View view, @FloatRange(from = 0, to = 1.0) float percentage) {
                        view.setAlpha(percentage);
                    }
                });

        addSlide(new SlideFragmentBuilder()
                        .backgroundColor(R.color.myWindowBackground)
                        .buttonsColor(R.color.myAccentColor)
                        .image(R.mipmap.ic_splash_screen)
                        .title("Organize your time with us")
                        .description("Would you try?")
                        .build(),
                new MessageButtonBehaviour(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        showMessage("We provide solutions to make you love your work");
                    }
                }, "Work with love"));

        addSlide(new SlideFragmentBuilder()
                .backgroundColor(R.color.myWindowBackground)
                .buttonsColor(R.color.myAccentColor)
                .title("Want more?")
                .description("Go on")
                .build());

        addSlide(new CustomSlide());

    }

    @Override
    public void onFinish() {
        Intent a=new Intent(IntroActivity.this, MainActivity.class);
        overridePendingTransition(R.anim.fade_in, R.anim.fade_out);
        startActivity(a);
        finish();
    }
}

CustomSlide Fragment (Privacy Policy checkbox fragment)

public class CustomSlide extends SlideFragment {
    private CheckBox checkBox;
    private SharedPreferences prefs;
    private SharedPreferences.Editor editor;
    private String terms;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        final View view = inflater.inflate(R.layout.fragment_custom_slide, container, false);

        prefs = getActivity().getPreferences(Context.MODE_PRIVATE);
        editor = prefs.edit();
        terms = prefs.getString("Policy", "Disagreed");

        checkBox = (CheckBox) view.findViewById(R.id.checkBox);
        return view;
    }

    @Override
    public int backgroundColor() {
        return R.color.myWindowBackground;
    }

    @Override
    public int buttonsColor() {
        return R.color.myAccentColor;
    }

    @Override
    public boolean canMoveFurther() {

        editor.putString("Policy", "Agreed");
        editor.commit();

        return checkBox.isChecked();
    }

    @Override
    public String cantMoveFurtherErrorMessage() {

        editor.putString("Policy", "Disagreed");
        editor.commit();

        return getString(R.string.error);
    }
}

MainActivity has nothing passed on and just starts.

Thank you, looking forward for some help.

Edit: My app shows the IntroSlider the first time I launch, but closing it without the checking the "Agree" checkbox in Privacy Policy (CustomSlide Fragment) and re-launching it directly shows Main Activity which defeats the purpose of having an agree button. Like the app should only show the main activity once the user has clicked on agree button.

Answer 1

For easier code control i will create 2 static method for get/put boolean on SharedPreferences for check if user Agreed/Disagreed:

for put boolean:

public static void Put_boolean(String key, boolean value, Context context) {
    SharedPreferences sharedPreferences =  context.getSharedPreferences("prefname", 0);
    SharedPreferences.Editor editor = sharedPreferences.edit();
    editor.putBoolean(key, value);
    editor.apply();
}

for get boolean:

public static boolean Get_boolean(String key, boolean defvak, Context context) {
    SharedPreferences sharedPreferences =  context.getSharedPreferences("prefname", 0);
    return sharedPreferences.getBoolean(key, defvak);
}

now we can save true value when user is agreed and false if user Disagreed, simply when your user Agreed/Disagreed call:

YourActivity.Put_boolean("isAgreed", true, context); //when Agreed
YourActivity.Put_boolean("isAgreed", false, context); //when Disagreed

when you want to check if user Agreed/Disagreed use:

final boolean checkifAgreed = YourActivity.Get_boolean("isAgreed", false, context);
if(checkifAgreed){
            //user is Agreed
        }else{
            //user is Disagreed
        }

i used static methods, so i can Get/Put SharedPreferences values from any activity using the same methods, hope this help you

Answer 2

You may or may not want to use it, but I made a Singleton service which handles my Shared preferences for me.

import android.content.Context;
import android.content.SharedPreferences;
import android.support.annotation.NonNull;

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;

public class SharedPreferencesService {
    private static final String DEBUG = "SharedPreferencesService";
    private static final String sharedPreferencesFileName = "SharedPrefsDB";
    private static SharedPreferencesService ourInstance = null;
    private SharedPreferences sharedPreferences;
    private SharedPreferences.Editor editor;
    private ExecutorService executorService;
    private HashMap<String, String> data = new HashMap<>();

    private SharedPreferencesService(Context context) {
        sharedPreferences = context.getSharedPreferences(sharedPreferencesFileName, Context.MODE_PRIVATE);
        editor = sharedPreferences.edit();
        executorService = Executors.newSingleThreadExecutor(new NamedThreadFactory());
        //Add data from file to RAM:
        Map<String, ?> entries = sharedPreferences.getAll();
        for (String key : entries.keySet()) {
            data.put(key, entries.get(key).toString());
        }
    }

    public static SharedPreferencesService getInstance(Context context) {
        if (ourInstance == null) {
            ourInstance = new SharedPreferencesService(context.getApplicationContext());
        }
        return ourInstance;
    }

    public void writeToPreferences(String key, String value) {
        executorService.execute(() -> editor.putString(key, value).commit());
        data.put(key, value);
        //Log.d(DEBUG,"Added "+key + " bytes:"+value.length() + " To prefs.");
    }

    public String getPreferenceSafe(String key) throws NoSuchPreferenceException {
        try {
            if (data.get(key) == null)
                throw new NoSuchPreferenceException("Token does not exist in RAM");
            return data.get(key);
        } catch (Exception e) {
            throw new NoSuchPreferenceException(key);
        }
    }

    public String getPreference(String key) {
        return data.get(key);
    }

    public void clearPreference(String key) {
        editor.putString(key, null).commit();
    }

    private class NamedThreadFactory implements ThreadFactory {
        @Override
        public Thread newThread(@NonNull Runnable r) {
            Thread thread = new Thread(r, "sp-db");
            thread.setDaemon(true);
            thread.setPriority(Thread.NORM_PRIORITY);
            return thread;
        }
    }

    public class NoSuchPreferenceException extends Exception {
        public NoSuchPreferenceException(String message) {
            super(message);
        }
    }
}

It adds data to the SharedPreferences file when you call writeToPreferences("key","value") but also adds it to a RAM held field in the class...so it is quick to get.

Answer 3

For easier implementation, you can use PowerPrefernce

https://github.com/AliAsadi/Android-Power-Preference

Save data

PowerPreference.getDefaultFile().put("isAgreed",true);

Get Data

PowerPreference.getDefaultFile().getBoolean("isAgreed");

Answer 4

Try change this line, in customslide fragment

prefs = getActivity().getPreferences(Context.MODE_PRIVATE);

to be

prefs = getActivity().getSharedPreferences("prefs", MODE_PRIVATE);

also use

editor.apply();

when you want to save your new data in preference. Hope it helps