Getting started with Android (11): Use the Intents link Activities links to transmit data

In addition to the ability to return data results from an Activity, it is also very common to transmit data to an Activity.

1. Create a project named PassData.

2. Code in main. xml.

[Java] <? Xml version = "1.0" encoding = "UTF-8"?>
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: orientation = "vertical">
 
<Button
Android: id = "@ + id/btn_SecondActivity"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: onClick = "onClick"
Android: text = "Click to go to Second Activity"/>
 
</LinearLayout>
<? Xml version = "1.0" encoding = "UTF-8"?>
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: orientation = "vertical">

<Button
Android: id = "@ + id/btn_SecondActivity"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: onClick = "onClick"
Android: text = "Click to go to Second Activity"/>

</LinearLayout> 3. Create the secondactivity. xml file in the res/layout folder.

[Java] <? Xml version = "1.0" encoding = "UTF-8"?>
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: orientation = "vertical">
 
<TextView
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: text = "Welcome to Second Activity"/>
 
<Button
Android: id = "@ + id/btn_MainActivity"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: onClick = "onClick"
Android: text = "Click to return to main activity"/>
 
</LinearLayout>
<? Xml version = "1.0" encoding = "UTF-8"?>
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: layout_width = "fill_parent"
Android: layout_height = "fill_parent"
Android: orientation = "vertical">

<TextView
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: text = "Welcome to Second Activity"/>

<Button
Android: id = "@ + id/btn_MainActivity"
Android: layout_width = "fill_parent"
Android: layout_height = "wrap_content"
Android: onClick = "onClick"
Android: text = "Click to return to main activity"/>

</LinearLayout> 4. Create an Activity subclass: SecondActivity. java.

[Java] package net. horsttnann. PassingData;
 
Import net. horsttnann. PassingData. R;
Import android. app. Activity;
Import android. content. Intent;
Import android.net. Uri;
Import android. OS. Bundle;
Import android. view. View;
Import android. widget. Toast;
 
Public class SecondActivity extends Activity {
@ Override
Public void onCreate (Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. secondactivity );
 
// --- Get the data passed in using getStringExtra ()---
Toast. makeText (this, getIntent (). getStringExtra ("str1 "),
Toast. LENGTH_SHORT). show ();
 
// --- Get the data passed in using getIntExtra ()---
Toast. makeText (this,
Integer. toString (getIntent (). getIntExtra ("age1", 0 )),
Toast. LENGTH_SHORT). show ();
 
// --- Get the Bundle object passed in ---
Bundle bundle = getIntent (). getExtras ();
 
// --- Get the data using the getString ()---
Toast. makeText (this, bundle. getString ("str2"), Toast. LENGTH_SHORT)
. Show ();
 
// --- Get the data using the getInt () method ---
Toast. makeText (this, Integer. toString (bundle. getInt ("age2 ")),
Toast. LENGTH_SHORT). show ();
}
 
Public void onClick (View view ){
// --- Use an Intent object to return data ---
Intent I = new Intent ();
 
// --- Use the putExtra () method to return some
// Value ---
I. putExtra ("age3", 45 );
 
// --- Use the setData () method to return some value ---
I. setData (Uri. parse ("Something passed back to main activity "));
 
// --- Set the result with OK and the Intent object ---
SetResult (RESULT_ OK, I );
 
// --- Destroy the current activity ---
Finish ();
}
}
Package net. horsttnann. PassingData;

Import net. horsttnann. PassingData. R;
Import android. app. Activity;
Import android. content. Intent;
Import android.net. Uri;
Import android. OS. Bundle;
Import android. view. View;
Import android. widget. Toast;

Public class SecondActivity extends Activity {
@ Override
Public void onCreate (Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. secondactivity );

// --- Get the data passed in using getStringExtra ()---
Toast. makeText (this, getIntent (). getStringExtra ("str1 "),
Toast. LENGTH_SHORT). show ();

// --- Get the data passed in using getIntExtra ()---
Toast. makeText (this,
Integer. toString (getIntent (). getIntExtra ("age1", 0 )),
Toast. LENGTH_SHORT). show ();

// --- Get the Bundle object passed in ---
Bundle bundle = getIntent (). getExtras ();

// --- Get the data using the getString ()---
Toast. makeText (this, bundle. getString ("str2"), Toast. LENGTH_SHORT)
. Show ();

// --- Get the data using the getInt () method ---
Toast. makeText (this, Integer. toString (bundle. getInt ("age2 ")),
Toast. LENGTH_SHORT). show ();
}

Public void onClick (View view ){
// --- Use an Intent object to return data ---
Intent I = new Intent ();

// --- Use the putExtra () method to return some
// Value ---
I. putExtra ("age3", 45 );

// --- Use the setData () method to return some value ---
I. setData (Uri. parse ("Something passed back to main activity "));

// --- Set the result with OK and the Intent object ---
SetResult (RESULT_ OK, I );

// --- Destroy the current activity ---
Finish ();
}
} 5. Code in AndroidManifest. xml.

[Java] <? Xml version = "1.0" encoding = "UTF-8"?>
<Manifest xmlns: android = "http://schemas.android.com/apk/res/android"
Package = "net. horsttnann. PassingData"
Android: versionCode = "1"
Android: versionName = "1.0" type = "codeph" text = "/codeph">
 
<Uses-sdk android: minSdkVersion = "10"/>
 
<Application
Android: icon = "@ drawable/ic_launcher"
Android: label = "@ string/app_name">
<Activity
Android: name = ". PassingDataActivity"
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 = "net. horsttnann. PassingData. SecondActivity"
Android: label = "Second Activity">
<Intent-filter>
<Action android: name = "net. horsttnann. PassingDataSecondActivity"/>
 
<Category android: name = "android. intent. category. DEFAULT"/>
</Intent-filter>
</Activity>
</Application>
 
</Manifest>
<? Xml version = "1.0" encoding = "UTF-8"?>
<Manifest xmlns: android = "http://schemas.android.com/apk/res/android"
Package = "net. horsttnann. PassingData"
Android: versionCode = "1"
Android: versionName = "1.0" type = "codeph" text = "/codeph">

<Uses-sdk android: minSdkVersion = "10"/>

<Application
Android: icon = "@ drawable/ic_launcher"
Android: label = "@ string/app_name">
<Activity
Android: name = ". PassingDataActivity"
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 = "net. horsttnann. PassingData. SecondActivity"
Android: label = "Second Activity">
<Intent-filter>
<Action android: name = "net. horsttnann. PassingDataSecondActivity"/>

<Category android: name = "android. intent. category. DEFAULT"/>
</Intent-filter>
</Activity>
</Application>

</Manifest> 6. Code in PassDataActivity.

7. debug by F11.

 

:

The program is started for the first time:


Jump to SecondActivity:

Return PassDataActivity:




From the column of horsttnann