Android Program Development: (2) use Intent-2.4 use Intent 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] view plaincopy <? 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. In the res/layout folder, create the secondactivity. xml file. [Java] view plaincopy <? 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] view plaincopypublic 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. The code in AndroidManifest. xml. [Java] view plaincopy <? 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. The code in PassDataActivity.
 
 
[Java] view plaincopyprint? Public class PassingDataActivity extends Activity {
/** Called when the activity is first created .*/
@ Override
Public void onCreate (Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. main );
}

Public void onClick (View view ){
Intent I = new
Intent ("net. learn2develop. PassingDataSecondActivity ");
 
// --- Use putExtra () to add new key/value pairs ---
I. putExtra ("str1", "This is a string ");
I. putExtra ("age1", 25 );
 
// --- Use a Bundle object to add new key/values
// Pairs ---
Bundle extras = new Bundle ();
Extras. putString ("str2", "This is another string ");
Extras. putInt ("age2", 35 );
 
// --- Attach the Bundle object to the Intent object ---
I. putExtras (extras );
 
// --- Start the activity to get a result back ---
StartActivityForResult (I, 1 );
}

Public void onActivityResult (int requestCode,
Int resultCode, Intent data)
{
// --- Check if the request code is 1 ---
If (requestCode = 1 ){
 
// --- If the result is OK ---
If (resultCode = RESULT_ OK ){
 
// --- Get the result using getIntExtra ()---
Toast. makeText (this, Integer. toString (
Data. getIntExtra ("age3", 0 )),
Toast. LENGTH_SHORT). show ();
 
// --- Get the result using getData ()---
Toast. makeText (this, data. getData (). toString (),
Toast. LENGTH_SHORT). show ();
}
}
}
 
}
Public class PassingDataActivity extends Activity {
/** Called when the activity is first created .*/
@ Override
Public void onCreate (Bundle savedInstanceState ){
Super. onCreate (savedInstanceState );
SetContentView (R. layout. main );
}

Public void onClick (View view ){
Intent I = new
Intent ("net. learn2develop. PassingDataSecondActivity ");
 
// --- Use putExtra () to add new key/value pairs ---
I. putExtra ("str1", "This is a string ");
I. putExtra ("age1", 25 );
 
// --- Use a Bundle object to add new key/values
// Pairs ---
Bundle extras = new Bundle ();
Extras. putString ("str2", "This is another string ");
Extras. putInt ("age2", 35 );
 
// --- Attach the Bundle object to the Intent object ---
I. putExtras (extras );
 
// --- Start the activity to get a result back ---
StartActivityForResult (I, 1 );
}

Public void onActivityResult (int requestCode,
Int resultCode, Intent data)
{
// --- Check if the request code is 1 ---
If (requestCode = 1 ){
 
// --- If the result is OK ---
If (resultCode = RESULT_ OK ){
 
// --- Get the result using getIntExtra ()---
Toast. makeText (this, Integer. toString (
Data. getIntExtra ("age3", 0 )),
Toast. LENGTH_SHORT). show ();
 
// --- Get the result using getData ()---
Toast. makeText (this, data. getData (). toString (),
Toast. LENGTH_SHORT). show ();
}
}
}
 
}
7. debug by F11.
 
 
 
 
:
 
The program is started for the first time:
 

Jump to SecondActivity:

Return PassDataActivity:

Written by manoel