安卓开发Activity:间的数据传递

实现效果

新建Android项目，实现页面的简单布局
activity_main.xml页面的布局

activity_main.xml页面的代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:src="@mipmap/ic_launcher" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <ImageView
            android:layout_width="50dp"
            android:layout_height="50dp"
            android:src="@mipmap/ic_launcher" />

        <EditText
            android:id="@ id/edit_name"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="请输入用户名" />
    </LinearLayout>

    <LinearLayout
        android:layout_marginTop="10dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <ImageView
            android:layout_width="50dp"
            android:layout_height="50dp"
            android:src="@mipmap/ic_launcher" />

        <EditText
            android:id="@ id/edit_pwd"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="请输入密码" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="horizontal">

        <TextView
            android:layout_marginTop="15dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="性  别"
            android:textSize="20sp" />

        <RadioGroup
            android:layout_marginTop="15dp"
            android:id="@ id/radio_group"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <RadioButton
                android:id="@ id/man"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="男"
                android:checked="true" />
            <RadioButton
                android:id="@ id/woman"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="女"
                />
        </RadioGroup>
    </LinearLayout>

    <Button
        android:id="@ id/btn_res"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="注册"/>

</LinearLayout>

编写MainActivity的代码

package com.example.datatranfer;

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.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {


    private EditText username;
    private EditText password;
    private RadioGroup radioGroup;
    private Button button;

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

        initView();
        initClickListener();
    }


    private void initView() {
        username = findViewById(R.id.edit_name);
        password = findViewById(R.id.edit_pwd);
        radioGroup = findViewById(R.id.radio_group);
        button = findViewById(R.id.btn_res);
    }

    private void initClickListener() {
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String verifyName = "";
                String verifyPwd = "";
                String sex = "";
                Intent it = new Intent(MainActivity.this, HomeActivity.class);
                verifyName = username.getText().toString();
                verifyPwd = password.getText().toString();

                //遍历RadioGroup找出被选中的单选按钮
                for (int i = 0; i < radioGroup.getChildCount(); i  ) {
                    RadioButton rb = (RadioButton) radioGroup.getChildAt(i);
                    if (rb.isChecked()) {
                        sex = rb.getText().toString();
                        break;
                    }
                }

                // 新建Bundle对象，把数据写入
                Bundle bundle = new Bundle();
                bundle.putCharSequence("verifyName", verifyName);
                bundle.putCharSequence("verifyPwd", verifyPwd);
                bundle.putCharSequence("sex", sex);

                it.putExtras(bundle);
                startActivity(it);
                // 关闭第一个Activity
                finish();
            }
        });
    }
}

新建HomeActivity类，实现数据传递回显

package com.example.datatranfer;

import androidx.appcompat.app.AppCompatActivity;

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

public class HomeActivity extends AppCompatActivity {

    private TextView text;
    private String username;
    private String password;
    private String sex;

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

        text = findViewById(R.id.textShow);

        // 获得intent对象，并且使用Bundle里面的数据
        Intent it = getIntent();
        Bundle bundle = it.getExtras();

        // 按键值的方式取出Bundle中的数据
        username = bundle.getCharSequence("verifyName").toString();
        password = bundle.getCharSequence("verifyPwd").toString();
        sex = bundle.getCharSequence("sex").toString();
        text.setText("欢迎"   username   "进入,"   "密码为："   password   ",性别为："   sex);
    }
}

编写HomeActivity类的视图activity_home.xml
activity_home.xml页面的代码

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

    <TextView
        android:id="@ id/textShow"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

这篇好文章是转载于：编程之路