java - 将评级栏的值传递给下一个 Activity/Intent

Question

问题:我无法将评分栏中的评分值/数据传递给另一个 Intent 。它只显示这个而不是评级栏中的值/数据。

Rating: MainActivity@79b604

我认为错误是它没有正确地从评级栏中获取值或者它没有正确传递值。这是我的代码:

MainActivity.java

public class MainActivity extends AppCompatActivity {
    String rating_float = "0.0";
    private TextView txtRatingValue;

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

    RatingBar ratingBar = (RatingBar) findViewById(R.id.ratingBar);

    ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {
        @Override
        public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {
            rating_float = String.valueOf(rating);
        }
    });
}

public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    Context context = getApplicationContext();
    CharSequence text = "";

    Intent intent_rating = new Intent(this, SecondActivity.class);
    intent_rating.putExtra("rating_float", toString());
    startActivity(intent_rating);

    return super.onOptionsItemSelected(item);
}}

SecondActivity.java

public class SecondActivity extends AppCompatActivity {
private TextView Msg;
String PassedValue = null;

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

    PassedValue = getIntent().getStringExtra("rating_float");
    Msg = (TextView) findViewById(R.id.Msg);
    Msg.setText("Dimension: 479\nFormat: JPEG\nSize: 360x360\nRating: " + PassedValue);
}

问题:

1. 我是否以正确的方式获取评分栏的值？
2. 如何将评分栏中的值/数据传递到下一个 Activity/Intent 以及如何从 SecondActivity.java 中获取它？

Answer 1

那是因为您将 MainActivity.toString() 的结果传递给您的第二个 Activity

代替

intent_rating.putExtra("rating_float", toString());

你大概应该写

intent_rating.putExtra("rating_float", this.rating_float);