因为我是在写监听网络的时候,不经意想起多级Activity是否可以数据传递(当然再此之前我一般都只是进行A-B的数据传递),因是临时想起,所以包名,XMl名,VIew id并不是很规范。
- Activity 传值基础
- 传递方式
- Intent
- Intent + Bundle
- 通用方式
- 多级Activity传递数据
- 效果
- 使用方式
Activity 传值基础
Activity之间传值的场景比较多见,也是入门的基础,在此重做记录
回头看,俩种方式的区别
-
Intent旨在数据传递
,bundle旨在存取数据
,当然intent也提供一部分数据的存取,但比起bundle就显得不专业,不灵活的多 Intent适合传递简单数据,bundle适合传递对象数据
intent传值内部代码也是使用了bundle
传递方式
Intent
其实intent可以传递很多类型的值
,提前知悉
我比较喜欢这种方式,因为懒,可以少写几行代码...
传递
Intent intent = new Intent(this, BActivity.class);
intent.putExtra("name","大帅哥");
startActivity(intent);
接收
Intent intent = getIntent();
String name = intent .getStringExtra("name")
Intent + Bundle
传递
Intent intent= new Intent(MainActivity.this,BActivity.class);
Bundle b=new Bundle();
b.putString("name","大帅哥");
b.putInt("age",21);
intent.putExtras(b);
startActivity(intent);
接收
Intent intent = getIntent();
Bundle data = intent.getExtras();
String name = data.getString("name");
Int age = data.getInt("age");
通用方式
传递 - (我是直接用的Intent,主要图方便
)
Intent sendIntent = new Intent();
sendIntent.putExtra("key",1);
startActivity(sendIntent);
需要注意:
sendIntent.putExtra("key", 可随意传各种类型数据,内部会自动转类型);
传递对象、实体类时记得进行序列化
接收
Intent方式
Intent receiveIntent = getIntent();
int key = receiveIntent.getIntExtra("key", 0);
接收数据Api
intent.get类型Extra("key")
intent.get类型Extra("key",需要提供一个默认值)
示例
获取Int传值
获取String传值
Bundle 方式
Intent receiveIntent = getIntent();
Bundle extras = receiveIntent.getExtras();
int key = extras.getInt("key");
可直接get对应类型,省得后面转类型
多级Activity传递数据
仅作为一种场景进行记录
效果
执行流程
运行结果
使用方式
Tip:
-
AndroidMainfest
注册Activity
<activity android:name=".SecoundActivity"/>
<activity android:name=".ThirdActivity"/>
- 代码中的
NetState
不用处理 -
Xml
中的隐藏View
不用处理
MainActivity(一级)
package com.example.dow.receiverdemo;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private TextView mState;
private TextView mBtn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// mState = (TextView) findViewById(R.id.net_state);
mBtn = (TextView) findViewById(R.id.mBtn_first);
mBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//传递数据
Intent intent=new Intent(MainActivity.this,SecoundActivity.class);
Bundle bundle = new Bundle();
bundle.putString("data","First数据传递");
intent.putExtras(bundle);
Log.e("tag","被点击");
startActivity(intent);
}
});
}
}
SecoundActivity(二级)
package com.example.dow.receiverdemo;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.TextView;
/**
* Created by YongLiu on 2017/5/24.
*/
public class SecoundActivity extends AppCompatActivity {
private TextView mBtn;
private String data;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_secound);
//获取intent传递数据
Intent intent = getIntent();
Bundle bundle = intent.getExtras();
data = (String) bundle.get("data");
Log.e("tag","MainFirst传输过来的数据===="+ data);
mBtn = (TextView) findViewById(R.id.mBtn_secound);
mBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//继续传递数据
Intent intent=new Intent(SecoundActivity.this,ThirdActivity.class);
Bundle bundle = new Bundle();
bundle.putString("data",data);
intent.putExtras(bundle);
startActivity(intent);
}
});
}
}
ThirdActivity(三级)
package com.example.dow.receiverdemo;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
/**
* Created by YongLiu on 2017/5/25.
*/
public class ThirdActivity extends AppCompatActivity {
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_third);
//获取数据
Intent intent = getIntent();
Bundle bundle = intent.getExtras();
String data = (String) bundle.get("data");
Log.e("tag","Secound传输过来的数据===="+data);
}
}
activity_main
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.dow.receiverdemo.MainActivity">
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/net_state"
android:visibility="gone"
android:layout_height="wrap_content"
android:text="隐藏的网络状态" />
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/mBtn_first"
android:layout_height="wrap_content"
android:text="事件多级传递" />
</LinearLayout>
activity_secound
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/net_state_secound"
android:visibility="gone"
android:layout_height="wrap_content"
android:text="隐藏的网络状态" />
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/mBtn_secound"
android:layout_height="wrap_content"
android:text="Secound事件多级传递" />
</LinearLayout>
activity_third
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/net_state_three"
android:visibility="gone"
android:layout_height="wrap_content"
android:text="隐藏的网络状态" />
<TextView
android:layout_width="match_parent"
android:gravity="center"
android:padding="5dp"
android:id="@+id/mBtn_three"
android:layout_height="wrap_content"
android:text="Third事件多级传递" />
</LinearLayout>