Check if an application is installed

[Eli Zuckerman]

How can I check if an app was installed on a device before trying to access it from another app? Is there any sort of checkApplicationManager method I can call?
Thank you.

[Monu Tripathi]

PackageManager is the class that you can use to get a list of all the installed packages.
Check this snippet out: it does the same

Maybe that can help.

[Monu Tripathi]

Alternatively, you can also create an Intent object with appropriate Component info and then check if the Intent is callable or not using the following function:

private boolean isCallable(Intent intent) {
	    List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent, 
	        PackageManager.MATCH_DEFAULT_ONLY);
	    return list.size() > 0;
}

[Eli Zuckerman]

Thanks. I'll try this out today

[martijn van gils]

Hi guys

I'm having the same problem as Eli,

but due to my lack of programming knowledge i don't know how to use it. If i want to check for the zxing Barcode scanner.

I tried some code but it doesn't really do anything.

public void callQrScan()
	{
	Intent intent1 = new Intent("com.google.zxing.client.android.SCAN");	
    
	if(isCallable(intent1)== true){
    	
    
    
    Context context = getApplicationContext();
	CharSequence text = "Scan Niet Gelukt";
	int duration = Toast.LENGTH_SHORT;

	Toast toast = Toast.makeText(context, text, duration);
	toast.show();
    }
    else{
    	Context context = getApplicationContext();
    	CharSequence text = "Scan Niet Gelukt";
    	int duration = Toast.LENGTH_SHORT;

    	Toast toast = Toast.makeText(context, text, duration);
    	toast.show();
    }
		
    
	Button tempbutton = (Button)findViewById(R.id.Button03);
	
	tempbutton.setOnClickListener(new OnClickListener()
	{
		public void onClick(final View v)
	{
				callQrScan();
	}
	});
    
	}
	
	private boolean isCallable(Intent intent1) {  
        		List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent1,   
            PackageManager.MATCH_DEFAULT_ONLY);  
        if(list.size() > 0)
        		return true ;  
        else
        	return false;
        
	}

i the toasts will be replaced with a popup that points the user to the market if the scanner is not allready installed.

thank you for your help beforehand.

[martijn van gils]

thanks guys with this code i finally got it to work.
just needed to keep hacking away at it :P

thanks anyway