java - 如何使用按钮将字符串值从一个 Activity 传递到两个不同的 Activity ？

Question

我想通过单击按钮将从 EditText 获得的值传递给两个 Activity 。我设法将值传递给一个 Activity ，将其显示在 TextView 中，我想对另一个 Activity 执行相同的操作，但我不确定 switch case 是否是正确的使用方法，因为只有一个按钮。

这是第一个 Activity 的代码:

public class ProfInfo1 extends Activity {

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.profinfo1);


    final EditText et0 = (EditText) findViewById (R.id.et_name);
    final EditText et1 = (EditText) findViewById (R.id.et_age);
    final EditText et2 = (EditText) findViewById (R.id.et_height);
    final EditText et3 = (EditText) findViewById (R.id.et_weight);

    Button back = (Button) findViewById(R.id.btn_back1);
    back.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {
        Intent a = new Intent(ProfInfo1.this, WelcomeActivity.class);
        startActivity(a);
    }

    });

    Button next = (Button) findViewById(R.id.btn_next1);
    next.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        Intent intent=new Intent(ProfInfo1.this, ViewProf1.class);
        intent.putExtra("name", et0.getText().toString());
        intent.putExtra("age", et1.getText().toString());
        intent.putExtra("height", et2.getText().toString());
        intent.putExtra("weight", et3.getText().toString());
        startActivity(intent);
    }
});


}   
}

这是显示值的第二个 Activity :

public class ViewProf1 extends Activity {
EditText age, height, weight;
String a, h, w;
Float age1, height1, weight1;
float bmi, cal;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.profinfo1view);

    TextView nameView = (TextView) findViewById (R.id.view_name);
    nameView.setText("Hello " + getIntent().getExtras().getString("name") + ",");
    TextView ageView = (TextView) findViewById (R.id.view_age);
    ageView.setText("Age: " + getIntent().getExtras().getString("age"));
    TextView heightView = (TextView) findViewById (R.id.view_height);
    heightView.setText("Your current height is " + getIntent().getExtras().getString("height") + " m.");
    TextView weightView = (TextView) findViewById (R.id.view_weight);
    weightView.setText("Your current weight is " + getIntent().getExtras().getString("weight") + " kg.");

    a = getIntent().getExtras().getString("age");
    h = getIntent().getExtras().getString("height");
    w = getIntent().getExtras().getString("weight");

    age1 = Float.valueOf(a).floatValue();
    height1 = Float.valueOf(h).floatValue();
    weight1 = Float.valueOf(w).floatValue();

    //bmi calculation
    bmi = (float) (weight1/Math.pow(height1, 2));
    TextView showresult = (TextView) findViewById (R.id.view_bmi);
    showresult.setText("Your BMI is " + Float.valueOf(bmi) + ".");

    //cal intake calculation
    cal = (float) (((655 + (9.6 * weight1) + (1.8 * height1) - (4.7 * age1)) * 1.2) - 550);
    TextView showcal = (TextView) findViewById (R.id.view_cal);
    showcal.setText("Your ideal daily calories intake is " + Float.valueOf(cal) + ".");

    //next button
    Button next2 = (Button) findViewById (R.id.btn_next2);
    next2.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {
        Intent a = new Intent(ViewProf1.this, FoodDiary.class);
        startActivity(a);
    }

    });

    //back button
    Button back2 = (Button) findViewById (R.id.btn_back2);
    back2.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {
        Intent a = new Intent(ViewProf1.this, ProfInfo1.class);
        startActivity(a);
    }

    });


}

第三个 Activity :

public class CompareWeight extends Activity {

EditText weight;
String w;
Float weight1;

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

    TextView weightView = (TextView) findViewById (R.id.test);
    weightView.setText("Your previous weight is " + getIntent().getExtras().getString("weight") + " kg.");

    w = getIntent().getExtras().getString("weight");

    weight1 = Float.valueOf(w).floatValue();
}
}

我只想将权重值传递给第三个 Activity 。

Answer 1

您一次只能将值传递给一个 Activity 。但是如果您想将权重值传递给第三个 Activity ，那么您可以在第一个 Activity 中设置它的值并在第三个 Activity 中检索它。 所以基本上我的意思是

1. 借助 putExtra 将您想要传递的值放入 SecondActivity。
2. 设置sharedPreference 变量。
3. startActivity( Intent );