Android笔记（二十） Activity中的跳转和值传递

2022-08-02 09:50:35

我们知道，一个APP是由若干个Activity组成的，那么各个Acitivity中肯定需要进行跳转以及传递数值以保证App的运行，现总结一下多个Activity之间的跳转和值传递。

显式Intent跳转

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity">

        </activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.os.Bundle;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

</LinearLayout>

从代码中可以看出，我们在一个Activity中，使用startActivity()传入一个Intent对象来实现Activity之间的跳转。

运行结果:

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

隐式Intent跳转

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity">

            <intent-filter>

                <action android:name="maintosecond" />

                <category android:name="android.intent.category.DEFAULT" />

            </intent-filter>

        </activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent("maintosecond");

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.os.Bundle;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

</LinearLayout>

         隐式Intent是在intent中指定激活组件的条件，程序会自动寻找最匹配的组件，然后进行跳转

         运行结果：

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

简单的传值

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity">

        </activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    Intent intent;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                intent = new Intent(MainActivity.this, SecondActivity.class);

                String str = ((EditText)findViewById(R.id.ed_input)).getText().toString();

                intent.putExtra("data",str);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.os.Bundle;

import android.util.Log;

import android.widget.TextView;

import org.w3c.dom.Text;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    TextView textView;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        String str = getIntent().getStringExtra("data");

        ((TextView)findViewById(R.id.tv_text_show)).setText(str);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

</LinearLayout>

运行结果：

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

通过代码可以看出，MainActivity使用putExtra(xx,yy)方法将yy传递给SecondActivity，而SecondActivity通过getStringExtra(xx)来接受传递过来的值

传入多个值

方法一：继续使用Intent

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity"></activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                intent.putExtra("string","hello world");

                intent.putExtra("int",104);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.widget.TextView;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        Intent intent = getIntent();

        int i = intent.getIntExtra("int",555);

        String str = intent.getStringExtra("string");

        ((TextView) findViewById(R.id.tv_text_show)).setText(i + "");

        ((TextView) findViewById(R.id.tv_text_2)).setText(str);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

    <TextView

        android:id="@+id/tv_text_2"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:textColor="#00ff00"

        android:textSize="90sp"/>

</LinearLayout>

方法二：使用Bundle

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity"></activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                Bundle b = new Bundle();

                b.putInt("int", 105);

                b.putString("string", "hello world");

                intent.putExtras(b);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.widget.TextView;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        Intent intent = getIntent();

        Bundle b = intent.getExtras();

        String str = b.getString("string");

        int i = b.getInt("int");

        ((TextView) findViewById(R.id.tv_text_show)).setText(i + "");

        ((TextView) findViewById(R.id.tv_text_2)).setText(str);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

    <TextView

        android:id="@+id/tv_text_2"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:textColor="#00ff00"

        android:textSize="90sp"/>

</LinearLayout>

运行结果：

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

         从代码可以看出，传入多个值可以直接在intent中put各种数据，也可以将数据打包成一个Bundle，然后将Bundle传入到新的Activity，新Activity接收到Bundle之后，可以从Bundle中get到打包的数据。

传入一个对象

方法一：Serializable方式

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity"></activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                Person person = new Person();

                person.setAge(20);

                person.setName("张三");

                intent.putExtra("person", person);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.widget.TextView;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        Intent intent = getIntent();

        Person person = (Person) intent.getSerializableExtra("person");

        String name = person.getName();

        int age = person.getAge();

        ((TextView) findViewById(R.id.tv_text_show)).setText(age + "");

        ((TextView) findViewById(R.id.tv_text_2)).setText(name);

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

    <TextView

        android:id="@+id/tv_text_2"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:textColor="#00ff00"

        android:textSize="90sp"/>

</LinearLayout>

Person.java

package cn.lixyz.activitymanager;

import java.io.Serializable;

/**

 * Created by LGB on 2015/8/28.

 */

public class Person implements Serializable {

    public Person() {

    }

    private String name;

    private int age;

    public String getName() {

        return name;

    }

    public int getAge() {

        return age;

    }

    public void setName(String name) {

        this.name = name;

    }

    public void setAge(int age) {

        this.age = age;

    }

}

运行结果：

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

方法二：Parcelable方式

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity"></activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                Person person = new Person();

                person.setAge(20);

                person.setName("张三");

                person.setHeight(180);

                Person person2 = new Person();

                person2.setAge(10);

                person2.setName("李四");

                person2.setHeight(178);

                intent.putExtra("person", person);

                intent.putExtra("person2",person2);

                startActivity(intent);

            }

        });

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.widget.TextView;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        Intent intent = getIntent();

        Person person = intent.getParcelableExtra("person");

        String name = person.getName();

        int age = person.getAge();

        int height = person.getHeight();

        Person person2 = intent.getParcelableExtra("person2");

        String name2 = person2.getName();

        int age2 = person2.getAge();

        int height2 = person2.getHeight();

        if (age2 > age) {

            ((TextView) findViewById(R.id.tv_text_show)).setText(age2 + "");

            ((TextView) findViewById(R.id.tv_text_2)).setText(name2);

            ((TextView) findViewById(R.id.tv_text_3)).setText(height2 + "");

        }else{

            ((TextView) findViewById(R.id.tv_text_show)).setText(age + "");

            ((TextView) findViewById(R.id.tv_text_2)).setText(name);

            ((TextView) findViewById(R.id.tv_text_3)).setText(height + "");

        }

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

    <TextView

        android:id="@+id/tv_text_2"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:textColor="#00ff00"

        android:textSize="90sp"/>

</LinearLayout>

Person.java

package cn.lixyz.activitymanager;

import android.os.Parcel;

import android.os.Parcelable;

import java.io.Serializable;

/**

 * Created by LGB on 2015/8/28.

 */

public class Person implements Parcelable {

    private String name;

    private int height;

    private int age;

    public static final Creator<Person> CREATOR = new Creator<Person>() {

        @Override

        public Person createFromParcel(Parcel in) {
 Person person = new Person();

            person.name = in.readString();

            person.age = in.readInt();

            person.height = in.readInt();

            return person;

        }

        @Override

        public Person[] newArray(int size) {

            return new Person[size];

        }

    };

    public String getName() {

        return name;

    }

    public int getAge() {

        return age;

    }

    public void setName(String name) {

        this.name = name;

    }

    public void setAge(int age) {

        this.age = age;

    }

    public int getHeight() {

        return height;

    }

    public void setHeight(int height) {

        this.height = height;

    }

    @Override

    public int describeContents() {

        return 0;

    }

    @Override

    public void writeToParcel(Parcel dest, int flags) {

        dest.writeString(name);

        dest.writeInt(age);

        dest.writeInt(height);

    }

}

运行结果

Android笔记（二十） Activity中的跳转和值传递Android笔记（二十） Activity中的跳转和值传递

注意Person.java中红色代码的部分

Activity中的数据回传

在Activity的跳转中，我们往往需要在关闭这个Activity之后向上一个Activity回传数据，但使用startActivity无法达到这个要求，Android提供了startActivityForResult方法来帮我们完成这一需求。

AndroidManiFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="cn.lixyz.activitymanager">

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme">

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity android:name=".SecondActivity"></activity>

    </application>

</manifest>

MainActivity.java

package cn.lixyz.activitymanager;

import android.content.Intent;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.Menu;

import android.view.MenuItem;

import android.view.View;

import android.widget.EditText;

import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        findViewById(R.id.bt_submit).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent(MainActivity.this, SecondActivity.class);

                startActivityForResult(intent, 1);

            }

        });

    }

    @Override

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {

        super.onActivityResult(requestCode, resultCode, data);

        switch (requestCode) {

            case 1:

                if (resultCode == RESULT_OK) {

                    String str = data.getStringExtra("string");

                    ((TextView) findViewById(R.id.tv_text_show2)).setText(str);

                }

        }

    }

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:orientation="vertical">

    <EditText

        android:id="@+id/ed_input"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:hint="请输入您想要传递的值"/>

    <Button

        android:id="@+id/bt_submit"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="提交"

        />

    <TextView

        android:id="@+id/tv_text_show2"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:textColor="#00ee00"

        android:textSize="30sp"/>

</LinearLayout>

SecondActivity.java

package cn.lixyz.activitymanager;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

/**

 * Created by LGB on 2015/8/27.

 */

public class SecondActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_second);

        findViewById(R.id.bt_cloBack).setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                Intent intent = new Intent();

                intent.putExtra("string", "hello world");

                setResult(RESULT_OK, intent);

                finish();

            }

        });

    }

}

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <TextView

        android:id="@+id/tv_text_show"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="默认文字"

        android:textColor="#00ff00"

        android:textSize="90sp" />

    <Button

        android:id="@+id/bt_cloBack"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="关闭并返回"/>

</LinearLayout>

运行结果：

Android笔记（二十） Activity中的跳转和值传递

Android笔记（二十） Activity中的跳转和值传递

Android笔记（二十） Activity中的跳转和值传递

从代码中可以看出

1. 我们使用startActivityForResult(intent, 1)来启动了SecondActivity，其中1是一个请求码，可以是任意数字，只要是唯一值即可

2. 我们在SecondActivity中构建了一个用来传递主句的Intent，然后调用了setResult()方法，该方法专门用于向上一个活动返回数据，该方法的第一个参数是向上一个活动返回处理结果，第二个参数是返回的数据

3. 由于我们是使用startActivityForResult来启动的第二个Activity，那么在第二个Activity销毁之后会调用上一个活动的onActivityResult()方法，所以我们重写该方法用来得到返回的数据

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