Calling system applications in Android

In my previous posts I have used reading contacts through API calls, however there is an easy method for doing standard tasks by calling system’s pre installed apps. In this post I am going to cover the details of how we can call the system apps through intents.

We are going to create a spinner control for providing the user some options and hit a submit button.

Here’s main.xml which defines the UI.

 <?xml version="1.0" encoding="utf-8"?>  
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
        android:orientation="vertical"  
        android:layout_width="fill_parent"  
        android:layout_height="fill_parent"  
     >  
   <Spinner  
       android:id="@+id/spinner1"  
       android:layout_width="match_parent"  
       android:layout_height="wrap_content"  
       android:entries="@array/application_array"  
       android:prompt="@string/app_prompt" />  
   <Button  
       android:id="@+id/btnSubmit"  
       android:layout_width="wrap_content"  
       android:layout_height="wrap_content"  
       android:text="Submit"  
       android:onClick="btnSubmitOnClick"/>  
 </LinearLayout>  

Spinner control requires a string array (application_array) for it’s entries which is defined in strings.xml.

 <?xml version="1.0" encoding="utf-8"?>  
 <resources>  
   <string name="app_name">callingsystemapps</string>  
   <string name="app_prompt">Choose a application</string>  
   <string-array name="application_array">  
     <item>Browser</item>  
     <item>Dialler</item>  
     <item>Map</item>  
     <item>Contacts</item>  
   </string-array>  
 </resources>  

In main.xml we have also have defined onClick method btnSubmitOnClick which is defined in MyActivity.java

   public void btnSubmitOnClick (View v)  
   {  
     Spinner spinner1 = (Spinner) findViewById(R.id.spinner1);  
     if (spinner1.getSelectedItem().toString().equals("Browser")){  
       Intent i = new  
           Intent(android.content.Intent.ACTION_VIEW,  
           Uri.parse("http://www.google.com"));  
       startActivity(i);  
     }  
     else if (spinner1.getSelectedItem().toString().equals("Dialler")){  
       Intent i = new  
           Intent(android.content.Intent.ACTION_DIAL);  
       startActivity(i);  
     }  
     else if (spinner1.getSelectedItem().toString().equals("Map")) {  
         Intent i = new  
             Intent(android.content.Intent.ACTION_VIEW,  
             Uri.parse("geo:37.827500,-122.481670"));  
         startActivity(i);  
     }  
     else if (spinner1.getSelectedItem().toString().equals("Contacts")) {  
       Intent i = new  
           Intent(android.content.Intent.ACTION_PICK);  
       i.setType(ContactsContract.CommonDataKinds.Phone.CONTENT_TYPE);  
       startActivity(i);  
     }  

Only difference between the four is the passing intent which is as below:

ACTION_VIEW
ACTION_DIAL
ACTION_PICK

Along with that we are passing parameters depending upon intent type. After that it’s just calling startActivity on the intent.

Try running the example and you shall get like this.