跳转与数据回传的实现

activity_main.xml

MainActivity.java

package com.example.chuanzhi;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.time.Instant;

public class MainActivity extends AppCompatActivity {
    private EditText et_name;
    private EditText et_yuwen;
    private EditText et_shuxue;
    private EditText et_yingyu;
    private EditText et_wuli;
    private EditText et_Java;
    private TextView hj1;
    private Button bt;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_name = (EditText) findViewById(R.id.et_name);
        et_yuwen = (EditText) findViewById(R.id.et_yuwen);
        et_shuxue = (EditText) findViewById(R.id.et_shuxue);
        et_yingyu = (EditText) findViewById(R.id.et_yingyu);
        et_wuli = (EditText) findViewById(R.id.et_wuli);
        et_Java = (EditText) findViewById(R.id.et_java);
        bt = (Button) findViewById(R.id.bt_zc);
        bt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                passDate();
            }
        });
    }

    private void passDate() {
        Intent intent = new Intent(this,Display.class);
        intent.putExtra("姓名", et_name.getText().toString().trim());
        intent.putExtra("语文", et_yuwen.getText().toString().trim());
        intent.putExtra("数学", et_shuxue.getText().toString().trim());
        intent.putExtra("英语", et_yingyu.getText().toString().trim());
        intent.putExtra("物理", et_wuli.getText().toString().trim());
        intent.putExtra("Java", et_Java.getText().toString().trim());
        //startActivity(intent);

       startActivityForResult(intent,1);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
         if(requestCode==1){
             if(resultCode==1){
                 String gts=data.getStringExtra("Java");
                 TextView  gts1=(TextView) findViewById(R.id.hj);
                 gts1.setText(gts);
             }
         }
    }

    public void hc(View view){
      hj1=(TextView) findViewById(R.id.hj1);
     double s1=Double.parseDouble(et_yuwen.getText().toString().trim());
     double s2=Double.parseDouble(et_shuxue.getText().toString().trim());
     double s3=Double.parseDouble(et_yingyu.getText().toString().trim());
     double s4=Double.parseDouble(et_wuli.getText().toString().trim());
     double s5=Double.parseDouble(et_Java.getText().toString().trim());
     double sumavg=(s1+s2+s3+s4+s5)/5;
     hj1.setText(""+sumavg);
    }
}

activity_display.xml

Display.java

package com.example.chuanzhi;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

public class Display extends AppCompatActivity {
    private TextView name;
    private TextView yuwen;
    private TextView shuxue;
    private TextView yingyu;
    private TextView wuli;
    private TextView Java;
    private TextView qz;
    String nm1;
    String yuwen1;
    String shuxue1;
    String yingyu1;
    String wuli1;
    String Java1;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_display);
        name=(TextView) findViewById(R.id.tv_name);
        yuwen=(TextView) findViewById(R.id.tv_yuwen);
        shuxue=(TextView) findViewById(R.id.tv_shuxue);
        yingyu=(TextView) findViewById(R.id.tv_yingyu);
        wuli=(TextView) findViewById(R.id.tv_wuli);
        Java=(TextView) findViewById(R.id.tv_java);


        Intent i=getIntent();
         nm1=i.getStringExtra("姓名");
        yuwen1=i.getStringExtra("语文");
        shuxue1=i.getStringExtra("数学");
        yingyu1=i.getStringExtra("英语");
        wuli1=i.getStringExtra("物理");
        Java1=i.getStringExtra("Java");

        name.setText("姓名："+nm1);
        yuwen.setText("语文："+yuwen1);
        shuxue.setText("数学："+shuxue1);
        yingyu.setText("英语："+yingyu1);
        wuli.setText("物理："+wuli1);
        Java.setText("Java："+Java1);

    }
    public void rt(View view){
        qz=(TextView) findViewById(R.id.tv_qz);
        String gts=qz.getText().toString();
        Intent is=new Intent();
        is.putExtra("Java",gts);
        setResult(1,is);
        finish();
    }
    public void qz(View view){
       yuwen=(TextView) findViewById(R.id.tv_yuwen);
        shuxue=(TextView) findViewById(R.id.tv_shuxue);
        yingyu=(TextView) findViewById(R.id.tv_yingyu);
        wuli=(TextView) findViewById(R.id.tv_wuli);
        Java=(TextView) findViewById(R.id.tv_java);
        qz=(TextView) findViewById(R.id.tv_qz);


       double yw1=Double.parseDouble(yuwen1);
        double sx1=Double.parseDouble(shuxue1);
        double yy1=Double.parseDouble(yingyu1);
        double wl1=Double.parseDouble(wuli1);
        double ja1=Double.parseDouble(Java1);

        Double avg=(yw1+sx1+yy1+wl1+ja1)/5;
        qz.setText("平均成绩："+(""+avg));
//          Double avg=(yw1)/5;
//          qz.setText(""+avg);

//        String yw=yuwen.getText().toString();
//        qz.setText(yw);

    }
}