Intent跳转的设置和Bundle的使用

//从ActivityA跳转至ActivityB

//跳转需在AndroidManfest.xml设置权限，

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.gradetest">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".ActivityA">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />15 
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".ActivityB" >
        </activity>
    </application>

</manifest>

ActivityA 写法

package com.example.gradetest; 
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends ActivityA {
    private Button button;
    Intent intent;
    Bundle bundle;

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

    public void initView(){
        button=(Button)findViewById(R.id.b1);       
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                intent= new Intent(ActivityA.this,ActivityB.class);

               /* bundle=new Bundle();
                bundle.putString("data","data from ActivityA");
                intent.putExtras(bundle);*/
                   //可以用bundle携带数据 ，取消注释即可                  

                startActivity(intent);
            }
        });

       

package com.example.gradetest;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
/**
 * Created by Administrator on 2018/1/10.
 */
public class Activity2 extends Activity {
    private Button button2;
    private Bundle bundle;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        initView2();
    }
    public void initView2(){
        button2=(Button)findViewById(R.id.b2);
        button2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                bundle=getIntent().getExtras();
                String text=bundle.getString("data");
                //获取bundle传过来的数据 
                button2.setText(text);
            }
        });
    }
}