Creating Intent using an ArrayList

Question

So I have an ArrayList, and I would like to create intent and switch activities using this piece of code (in ListAdapter class):

for (int i = 0; i <= activityList.size(); i++){

    if (position == i){
        Intent intent = new Intent(context, (activityList.get(i).getName()).class);
        context.startActivity(intent);
    }
}

I am getting an 'identifier expected' error around .class.

I do have a working piece of code, that does what I want, but I have to specify the class (which isn't what I want) here:

if (position == 0) {
    Intent intent = new Intent(context, NextActivity.class);
    context.startActivity(intent);
}

Not exactly sure why the 1st piece of code isn't working. Any help would be greatly appreciated.

1) i dont think you need = sign in the <= list.size(). 2) what is activityList? I know its a List... but a List of what? Strings? Because that will not work.... becuase thens it "nextactivity".class — letsCode, Jul 24 '18 at 18:45
uhhhh....yeah. because NextActivity isn't a String.... its a filename. — letsCode, Jul 24 '18 at 18:56
Ah, not sure why I didn't think about that. Thanks, gonna change some things up then — Slavic the Slavic, Jul 24 '18 at 19:03

score 1 · Accepted Answer · answered Jul 24 '18 at 18:58

you need to pass Class type as Intent's second parameter, where you are using

Intent intent = new Intent(context, (activityList.get(i).getName()).class);

in this type of case you would need List<Class> like

List<Class> activityList = Arrays.asList(ActivityA.class, ActivityB.class, ActivityC.class);

the use it like this:

Intent intent = new Intent(context, activityList.get(i));

I'd suggest to change your List<String> to List<Class>.

score 0 · Answer 2 · answered Jul 24 '18 at 19:20

0

The simplest way to this job is to convert your String to class. Here is a code to do that-

for (int i = 0; i <= activityList.size(); i++){
    if (position == i){
        String activity = "YourPackageName."+arrayList.get(i).getName();
        Intent intent = null;

        try {
            intent = new Intent(context, Class.forName(activity));
        } 
        catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        context.startActivity(intent);
    }
}

The model should return the class name without class keyword. Eg:-Main2Activity

answered Jul 24 '18 at 19:20

Raj

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I tried that, but its giving me this error 'Attempt to invoke virtual method 'boolean android.content.Intent.migrateExtraStreamToClipData()' on a null object reference' – Slavic the Slavic Jul 24 '18 at 19:34
Plz send the model and what type of data are you adding in array list @SlavictheSlavic – Raj Jul 24 '18 at 19:36
I'm just sending an array list of 4 strings to my ListAdapter. Also I had to change your 'arrayList' to 'activityList', I believe that's what you meant. – Slavic the Slavic Jul 24 '18 at 19:42
Your array list must be of type object. Also can you mention the strings that you are passing to the list ? – Raj Jul 24 '18 at 19:44
Ah, alright. I'm just passing ("one", "two", "three", "four") simple test strings – Slavic the Slavic Jul 24 '18 at 19:47
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/176674/discussion-between-raj-and-slavic-the-slavic). – Raj Jul 24 '18 at 19:47

Creating Intent using an ArrayList

2 Answers2