Android button / new mainactivity 按鈕開新視窗/主視窗

MainActivity.java

 public void button_02(View view)

{
    Intent intent = new Intent();
    intent.setClass(this, MainActivity02.class);
    startActivity(intent);
    //startActivity(new Intent(this, MainActivity2.class));
}

AndroidManifest.xml

<intent-filter>
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>