意向活动切换为随机活动

Question

iam trying to switch from say activity 1 to activity 2 when a button is clicked. and ive got how to do that. what i cant figure out is how to get it so 50% of the time it goes to activity 2 and the other 50% to activity 3. iam sorry i know its a very obvious question. iam new to this so could you please explain a little and also similar effects like switching to completely randomn out of say 5 different specified activites. thanks in advance ... intent code below. please explain using my code if possible.

 yes.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            Intent yes1=new Intent(MainActivity.this,Question2.class);
            startActivity(yes1);

Answer 1

Off the top of my head, so it might not compile completely :-) but the idea is sound

List<Class<? extends Activity>> activities = new ArrayList<Class<? extends Activity>>();
activities.add(Question.class);
activities.add(Question2.class);

Random generator = new Random();
Class<? extends Activity> randomActivity = activities.get(generator.nextInt(activities.size()));

Intent intent = new Intent(this, randomActivity);
startActivity(intent);

Answer 2

You could just use Random class to decide which will be your next intent. Please, take this code snippet as an example.-

Intent newIntent = null;
Random rand = new Random();

int index = rand.nextInt(4);
switch (index) {
    case 0:
        newIntent = new Intent(this, Question1.class);
    break;
    case 1:
        newIntent = new Intent(this, Question2.class);
    break;
    case 2:
        newIntent = new Intent(this, Question3.class);
    break;
    case 3:
        newIntent = new Intent(this, Question4.class);
    break;
}

startActivity(newIntent);

Answer 3

Try this:

yes.setOnClickListener(new View.OnClickListener() {

   @Override
   public void onClick(View arg0) {
       double rand = Math.random();
       if(rand < 0.5){
           Intent yes1 = new Intent(MainActivity.this, Question2.class);
           startActivity(yes1);
       } else {
           Intent yes2 = new Intent(MainActivity.this, Question3.class);
           startActivity(yes2);
       }
   }
});

Similar for random switching between 5 different activities. You could probably optimize it so you're not just if branching between all your different options if you have so many different activities.

Answer 4

You could set up a String Array of the class names like

String[] classes = new String[3];
classes[0] = Activity1;
classes[1] = Activity2;
classes[2] = Activity3;

Then use a Random number to pick between them and on click do something like

 @Override
    public void onClick(View arg0) {
        // TODO Auto-generated method stub
        Random r = new Random();
        int number = r.nextInt(4);
        String curClass = classes[number);
        Intent yes1=new Intent(MainActivity.this,Class.forName(curClass));
        startActivity(yes1);