如何更新android textview的文本

Question

I am creating a quiz game in android using java, Its first activity contains a TextView that represents the points earned ,displays the value stored in SharedPreference variable, This value is increasing if the user moves to another activities or playing game,But the textview in first activity still displays the initial value (It displays the final value only if i restart application), How can I solve this issue without using startActivityforresult

First activity code

                int mode4 = Activity.MODE_PRIVATE;
                SharedPreferences data = getSharedPreferences("data", mode4);
                Integer coins = data.getInt("coins", 0);
                String coinsString = coins.toString();
                TextView coinView = (TextView) findViewById(R.id.coins);
                coinView.setText(coinsString);

Final activity code

public void a_click(View ClickedButton)
{
    int mode=Activity.MODE_PRIVATE;
    SharedPreferences my=getSharedPreferences("alpha",mode);
    String z=my.getString("correct","data_loss");

    SharedPreferences data=getSharedPreferences("data",mode);
    Integer coins=data.getInt("coins", 0);
    if(z.compareTo("1")==0)
    {
        int mode66=Activity.MODE_PRIVATE;
        SharedPreferences my66=getSharedPreferences("session",mode66);
        int zedd=my66.getInt("qnum", 1);
        int coinsP=0;
        if(zedd==1)
        {
            coinsP=coins+5;
        }
        if(zedd==2)
        {
            coinsP=coins+5;
        }
        if(zedd==3)
        {
            coinsP=coins+10;
        }
        if(zedd==4)
        {
            coinsP=coins+15;
        }
        if(zedd==5)
        {
            coinsP=coins+20;
        }
        if(zedd==6)
        {
            coinsP=coins+25;
        }

        qnum++;
        mugu(qnum);
        SharedPreferences dataP=getSharedPreferences("data",mode);
        SharedPreferences.Editor e2=dataP.edit();
        e2.putInt("coins", coinsP);
        e2.commit();
    }

Answer 1

Override the resume method and set text in textview there as show below.

@Override
public void onResume() {
    super.onResume();  // Always call the superclass method first
   textView.setText("YourText");
}

Answer 2

Calling startActivityforresult() is not a solution as it is not for this. What you should do is simply update your UI in onResume() which will be called whenver your Activity goes to foreground (ie when user gets back from other activities)

@Override
public void onResume() {
   super.onResume();

   textView.setText(hiscore);
}

Answer 3

 public class MainProjectActivity extends Activity {
    /** Called when the activity is first created. */
   TextView displayScores;
    static int Score = 0;
   @Override
  protected void onResume(){
    super.onResume();
    // update your data here
        spSettings = getSharedPreferences(KEY,"VALUE");
        displayScores.setText(spSettings.getString("YOUR KEY",     
        "YOURVALUE")); 

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

        //Display Scores
        displayScores = (TextView)findViewById(R.id.scoreDisplay);
        displayScores.setText("Your Score : "+ Score);

        //Play Game button activity
        Button gameButton = (Button)findViewById(R.id.PlayButton);
        gameButton.setOnClickListener(new OnClickListener() {

            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent play = new Intent(getApplicationContext(), com.sample.game.PlayScreen.class);
                startActivity(play);
            }
        });

Answer 4

put this code in your mainactivity

Timer().scheduleAtFixedRate(new TimerTask() {
       public void run() {
                runOnUiThread(new Runnable() {
            public void run() {
                int mode = Activity.MODE_PRIVATE;
                SharedPreferences data = getSharedPreferences("data", mode);
                Integer coins = data.getInt("coins", 0);
                String coinsString = coins.toString();
                TextView coinView = (TextView) findViewById(R.id.coins);
                coinView.setText(coinsString);
            }
        });
        }
    }, 0, 500);

this code will update your textview for every 0.5 seconds

Answer 5

As you are storing the data in Shared Preference so you can add listener for your preferences, as follows.

   //Here you can register for changes in preference object
   preferences.registerOnSharedPreferenceChangeListener(listener);

Listener implementation will be as follows

SharedPreferences.OnSharedPreferenceChangeListener listener = new SharedPreferences.OnSharedPreferenceChangeListener() {
        public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
            // Implementation
            tv.setText(prefs.getString(key, "defalut"));
        }
    };