Intent i = new Intent(firstactivity.this, secondactivity.class);
startActivity(i);

Button button = findViewById(R.id.button);
    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent(SplashActivity.this,HomeActivity.class);
            startActivity(intent);
        }
    });

当用户点击按钮时，直接在XML中，就像这样:

<Button
         android:id="@+id/button"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="TextButton"
         android:onClick="buttonClickFunction"/>

使用属性android:onClick我们声明方法名必须出现在父活动上。所以我必须在我们的活动中创建这个方法，像这样:

public void buttonClickFunction(View v)
{
            Intent intent = new Intent(getApplicationContext(), Your_Next_Activity.class);
            startActivity(intent);
}

在发送活动中尝试以下代码

   //EXTRA_MESSAGE is our key and it's value is 'packagename.MESSAGE'
    public static final String EXTRA_MESSAGE = "packageName.MESSAGE";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
       ....

        //Here we declare our send button
        Button sendButton = (Button) findViewById(R.id.send_button);
        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //declare our intent object which takes two parameters, the context and the new activity name

                // the name of the receiving activity is declared in the Intent Constructor
                Intent intent = new Intent(getApplicationContext(), NameOfReceivingActivity.class);

                String sendMessage = "hello world"
                //put the text inside the intent and send it to another Activity
                intent.putExtra(EXTRA_MESSAGE, sendMessage);
                //start the activity
                startActivity(intent);

            }

从接收活动尝试以下代码:

   protected void onCreate(Bundle savedInstanceState) {
 //use the getIntent()method to receive the data from another activity
 Intent intent = getIntent();

//extract the string, with the getStringExtra method
String message = intent.getStringExtra(NewActivityName.EXTRA_MESSAGE);

然后将以下代码添加到AndroidManifest.xml文件中

  android:name="packagename.NameOfTheReceivingActivity"
  android:label="Title of the Activity"
  android:parentActivityName="packagename.NameOfSendingActivity"

一个老问题，但如果目标是切换显示的页面，我只有一个活动，当我想切换页面时调用setContentView()(通常是响应用户单击按钮)。这允许我简单地从一个页面的内容调用到另一个页面。没有意图疯狂的额外包裹捆绑和任何试图来回传递数据。

我像往常一样在分辨率/布局中做了一堆页面，但没有为每个页面做一个活动。只需使用setContentView()来根据需要切换它们。

所以我的一个和唯一的onCreate()有:

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    LayoutInflater layoutInflater = getLayoutInflater();

    final View mainPage = layoutInflater.inflate(R.layout.activity_main, null);
    setContentView (mainPage);
    Button openMenuButton = findViewById(R.id.openMenuButton);

    final View menuPage = layoutInflatter.inflate(R.layout.menu_page, null);
    Button someMenuButton = menuPage.findViewById(R.id.someMenuButton);

    openMenuButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            setContentView(menuPage);
        }
    });

    someMenuButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            do-something-interesting;
            setContentView(mainPage);
        }
    }
}

如果你想要返回按钮在退出应用程序之前返回内部页面，只需包装setContentView()将页面保存在一个小的页面堆栈中，并在onBackPressed()处理程序中弹出这些页面。

像下面这样在xml中放置按钮小部件

<Button
    android:id="@+id/button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Button"
/>

在此之后，初始化和处理点击监听器在活动如下..

在Activity On Create方法中:

Button button =(Button) findViewById(R.id.button); 
button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
       Intent intent = new 
            Intent(CurrentActivity.this,DesiredActivity.class);
            startActivity(intent);
    }
});