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If you have saved data in Shared Preferences then you simply need use setText() on text view.

public class MainActivity extends AppCompatActivity {

    //your global variables here

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        TextView textView = findViewById(R.id.text_view);
        //some more textView  or other views initialization here

        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
        //get saved value from SharedPreferences
        String saveText = sharedPreferences.getString("PREFERENCE_KEY", defaultValue);
        //some more saved value in similar manner

        //set saved value on TextView
        textView.setText(saveText);
    }
}

As onCreate() method will execute on every launch of app so as textView.setText(saveText).

Now for the very first install of app,there is no data will be saved in SharedPreferences so sharedPreferences.getString() will use defaultValue you have provied.

If you just want to show some sample data on TextView on each startup, then you can android:text="sample_data_value" in your layout xml file as follow-

<TextView
    .......
    android_text="sample_data_value"/>

Happy Coding !

I have this app i’m experimenting on. wherein the user will input data, saves it onto sharedpreferences and displays it. I already manage to do those three. except when relaunching the app. the details that should still be displayed on Textview disappears. is there a way for it not to disappear after relaunching?
saved and displayed before relaunching the app
after relaunching the app

Ps. I’m a beginner on android studio