Determining if an Activity exists on the current device?

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攒了一身酷
攒了一身酷 2020-11-29 06:28

Is there a way to check and see if an Activity exists on your device? If I have a youtube video link I want to specify it open in the YouTube PlayerActivity. However, I don\

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  • 2020-11-29 06:58

    Here's how I check if an Activity is available on the device:

            Intent intent = new Intent(Intent.ACTION_CALL);
            intent.setData(Uri.parse("tell//:" + phoneNumber));
    
            PackageManager manager = context.getPackageManager();
            List<ResolveInfo> activities = manager.queryIntentActivities(
                    intent, 0);
            if (!manager.hasSystemFeature(
                    PackageManager.FEATURE_TELEPHONY) || activities == null || activities
                    .size() < 1) {
                Toast.makeText(
                        context,
                        "Sorry, there were no apps that worked with that request.",
                        Toast.LENGTH_SHORT).show();
            } else {
                context.startActivity(intent);
            }
    
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  • 2020-11-29 07:00

    I don't think I can catch the runtime exception

    Actually, this works:

    try {
        startActivity(new Intent(..));
    } catch (ActivityNotFoundException e) {
        Toast.makeText(this, "Not installed.", LENGTH_SHORT).show();
    }
    
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  • 2020-11-29 07:03

    I ended up doing:

            Intent intent = new Intent();
            intent.setClassName( "com.google.android.gsf", "com.google.android.gsf.login.AccountIntroActivity" );
    
            if(getContext().getPackageManager().resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY) != null) {
                getContext().startActivity( intent );
            } else {
                getContext().startActivity(new Intent(Settings.ACTION_ADD_ACCOUNT));
            }
    

    This ensures that the google-specific Add Account intent exists, and if not, falls back on the general more general ACTION_ADD_ACCOUNTS.

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  • 2020-11-29 07:15

    You could create an Intent object with necessary component info and then check if the intent is callable or not.I stumbled upon this snippet here on SO, don't have the link to the actual thread.

    private boolean isCallable(Intent intent) {
            List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent, 
                PackageManager.MATCH_DEFAULT_ONLY);
            return list.size() > 0;
    }
    
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  • 2020-11-29 07:20

    This is the simplest way to do this:

    boolean activityExists = intent.resolveActivityInfo(getPackageManager(), 0) != null;
    

    It is also the one recommended by Google:

    To first verify that an app exists to receive the intent, call resolveActivity() on your Intent object. If the result is non-null, there is at least one app that can handle the intent and it's safe to call startActivity(). If the result is null, you should not use the intent and, if possible, you should disable the feature that invokes the intent.

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