你可以试试下面的代码:

Intent myIntent = new Intent();
FirstActivity.this.SecondActivity(myIntent);

你可以试试下面的代码:

Intent myIntent = new Intent();
FirstActivity.this.SecondActivity(myIntent);

你的按钮xml:

 <Button
    android:id="@+id/btn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="jump to activity b"
    />

Mainactivity.java:

 Button btn=findViewVyId(R.id.btn);
btn.setOnClickListener(btnclick);
btnclick.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
               Intent intent=new Intent();
                intent.setClass(Mainactivity.this,b.class);
                startActivity(intent);
    }
});

    Intent in = new Intent(getApplicationContext(),SecondaryScreen.class);    
    startActivity(in);

    This is an explicit intent to start secondscreen activity.

 imageView.setOnClickListener(v -> {
// your code here
        });

以马内利,

我认为额外的信息应该放在启动活动之前，否则数据将不可用，如果你在NextActivity的onCreate方法中访问它。

Intent myIntent = new Intent(CurrentActivity.this, NextActivity.class);

myIntent.putExtra("key", value);

CurrentActivity.this.startActivity(myIntent);