Android studio实现页面信息的交互，将第一个页面的内容传给第二个页面接受显示，再返回信息给第一个页面进行接收显示

MainActivity5.java

package com.example.myapplication_one;

import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity5 extends AppCompatActivity implements View.OnClickListener {
    
    
    private EditText editText1;
    private EditText editText2;
    private Button button1, button2;
    ImageView imageView1,imageView2;
    TextView textView1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
    
    
        super.onCreate(savedInstanceState);
        //用于加载页面布局   R.layout.名称
        setContentView(R.layout.layout5);
        init();
        button1.setOnClickListener(this);
        button2.setOnClickListener(this);
    }

    private void init() {
    
    
        button1 = findViewById(R.id.button1);
        button2 = findViewById(R.id.button2);
        editText1 = findViewById(R.id.editText1);
        editText2 = findViewById(R.id.editText2);
        imageView1 = findViewById(R.id.imageView1);
        imageView2 = findViewById(R.id.imageView2);
        textView1 = findViewById(R.id.textView1);
    }

    public void onClick(View view) {
    
    
        switch (view.getId()) {
    
    
            case R.id.button1:
                //点击button1时的操作
                //context:上下文，text：显示的文本的信息，duration：显示时间
                String name1 = editText1.getText().toString();
                String name2 = editText2.getText().toString();

                /*
                 * Intent:意图，显式启动  ————  隐式启动
                * Intent intent = new Intent(PackageContext,cls);
                 * PackageContext :上下文
                 * cls：想要启动的目标活动
                 */
                //显式启动Intent
                //Intent intent = new Intent(MainActivity3.this,MainActivity4.class);
                //startActivity(intent);
                if(name1.equals("admin")  && name2.equals("123")){
    
    
                    imageView1.setImageResource(R.drawable.ic_launcher_background);
                    Intent intent = new Intent(MainActivity5.this,MainActivity4.class);
                    intent.putExtra("UserName", name1);//键值对
                    intent.putExtra("Password" ,name2);
                    //startActivity(intent);
                    startActivityForResult(intent,1001);//1001表示请求码
                }else{
    
    
                    Toast.makeText(MainActivity5.this, "你输入的用户信息不正确", Toast.LENGTH_LONG).show();
                    editText1.setText("");
                    editText2.setText("");
                }
                break;
            case R.id.button2:
                Toast.makeText(MainActivity5.this, "点击button按钮2", Toast.LENGTH_LONG).show();
                imageView2.setImageResource(R.drawable.ic_launcher_background);
                AlertDialog.Builder dialog = new AlertDialog.Builder(MainActivity5.this);
                dialog.setTitle("Dialog");
                dialog.setMessage("是否进行注册");
                dialog.setPositiveButton("确定", new DialogInterface.OnClickListener() {
    
    
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
    
    
                        finish();
                    }
                });//积极的按钮
                dialog.setNegativeButton("取消", new DialogInterface.OnClickListener() {
    
    
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
    
    
                        finish();
                    }
                });//消极的按钮
                dialog.show();
                break;
            default:
                break;
        }
    }
    //onActivityResult()方法，作用接受第二活动传递的数据
    //int requestCode:请求码，startActivityForResult(intent,1001);
    //int resultCode：结果码， setResult(1002,intent);
    //Intent data ：第二个页面封装的数据，setResult(1002,intent);
    protected void onActivityResult(int requestCode,int resultCode,Intent data){
    
    
        super.onActivityResult(requestCode,resultCode,data);
        switch (requestCode){
    
    
            case 1001:
                if(resultCode==1002){
    
    
                    String info = data.getStringExtra("info");
                    textView1.setText(info);
                }
                break;
        }
    }
}

layout5

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="24dp"
        android:text="@string/User" />
    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/textView1"
        android:layout_toRightOf="@id/textView1"
        android:hint="请输入用户名"
        android:maxLines="2"
        android:ems="10">
        <requestFocus/>
    </EditText>
    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/textView1"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="27dp"
        android:text="@string/Password" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/textView2"
        android:layout_toRightOf="@id/textView2"
        android:ems="10"
        android:hint="请输入密码"
        android:inputType="textPassword" />

    <Button
        android:id="@+id/button1"
        android:layout_width="233dp"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText2"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="88dp"
        android:layout_marginTop="46dp"
        android:layout_marginRight="89dp"
        android:textAllCaps="true"
        android:text="登录" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="50dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="88dp"
        android:layout_marginTop="270dp"
        android:layout_marginRight="89dp"
        android:background="#ff0000"
        android:gravity="center"
        android:text="TextView"
        android:textColor="#00ff00"
        android:textSize="35sp" />

    <Button
        android:id="@+id/button2"
        android:layout_width="233dp"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText2"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_marginLeft="88dp"
        android:layout_marginTop="100dp"
        android:layout_marginRight="89dp"
        android:textAllCaps="true"
        android:text="注册" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="138dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="68dp"
        android:layout_marginTop="350dp"
        app:srcCompat="@mipmap/f1" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="wrap_content"
        android:layout_height="92dp"
        android:layout_marginLeft="228dp"
        android:layout_marginTop="350dp"
        app:srcCompat="@mipmap/f2" />

</RelativeLayout>

MainActivity4.java

package com.example.myapplication_one;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity4 extends AppCompatActivity {
    
    

    TextView textView1,textView2;
    Button button1;
    EditText editText1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
    
    
        super.onCreate(savedInstanceState);
        //用于加载页面布局   R.layout.名称
        setContentView(R.layout.layout4);
        init();
        Intent intent = getIntent();//getIntent();获取当前intent对象
        String userName = intent.getStringExtra("UserName");
        String password = intent.getStringExtra("Password");
        textView1.setText(userName+password);
        textView2.setText(userName+password);
        button1.setOnClickListener(new View.OnClickListener() {
    
    
            @Override
            public void onClick(View view) {
    
    
                Intent intent = new Intent();
                //使用Intent对象封装数据
                intent.putExtra("info",editText1.getText().toString());
                //将数据返回到第一个页面
                setResult(1002,intent);
                finish();//关闭当前的Activity（关闭第二个页面，回到第一个页面）
            }
        });
    }

    private void init(){
    
    
        textView1 = (TextView) findViewById(R.id.textView2);
        textView2 = (TextView) findViewById(R.id.textView3);
        button1 = (Button) findViewById(R.id.button1);
        editText1 = (EditText) findViewById(R.id.editText1);
    }
}

layout4

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="48dp"
        android:background="#00ff00"
        android:gravity="center"
        android:text="第二个活动"
        android:textColor="@color/purple_200"
        android:textSize="25dp" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="70dp"
        android:layout_weight="1"
        android:text="Username" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="120dp"
        android:layout_marginTop="40dp"
        android:layout_weight="1"
        android:ems="10" />

    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="120dp"
        android:layout_weight="1"
        android:text="Password" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPassword"
        android:layout_marginLeft="120dp"
        android:layout_marginTop="100dp"/>

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="160dp"
        android:text="返回数据" />
</RelativeLayout>