How to put Extras to different activity?

问题

For example, i have 3 activities.. I also use Tab host with separate activity when switch tab widget.

1) FoodTypeListActivity.class:there is a list of food type i.e. Breakfast, Dinner, Lunch..

2) MainTabActivity.class : Tabhost which has 3 tab widget

3) FoodListActivity.class : this activity is one of tab widget

I have a headlabel in layout of MainTabActivity.class which will show type of food as Textview from the previous activity(FoodTypeListActivity.class)

The problem is; i want to send the name of type of food from (FoodTypeListActivity.class) to set as headlabel in (MainTabActivity.class) and send id of food type (FoodTypeListActivity.class) to (FoodListActivity.class)

How do i implement putExtra to send data to different activity in on ListItem click of FoodTypeListActivity.class

Now i have the the following code in FoodTypeListActivity.class

lv.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view,int position, long id) {


              if(position==0){
                Intent i = new Intent(FoodTypeListActivity.this, MainTabActivity.class);  

                i.putExtra("foodTypeID", 3);
                i.putExtra("foodTypeName", "Breakfast");
                startActivity(i);

              } 

            }
          });

Thanks you

回答1:

You should just use shared preference.

In your listview click use this to put the values in shared preference.

  SharedPreferences items = getSharedPreferences("my_food_data", 0);
  SharedPreferences.Editor editor = settings.edit();
  editor.putInt("foodTypeID", 3);
  editor.putString("foodTypeName", "Breakfast"); 
  editor.commit(); //VERY important

Now to pull the data out in ANY activity use..

   SharedPreferences items = getSharedPreferences("my_food_data", 0);
   int foodId = settings.getInt("foodTypeId", 0);
   String foodTitle = items.getString("foodTypeName", "No Name"); //the default value of of "no name will be used if nothing is in the preference file.

I think this works well for what you are trying to do.

回答2:

That looks exactly correct. Now on your receiving activity just use the following code to retrieve your value.

    int foodTypeId = getIntent().getIntExtra("foodTypeID", -1);
    String foodTypeName= getIntent().getStringExtra("foodTypeName");

The -1 is the default value if there is not value with the given key. That default value should never actually be needed unless you forget to pass in a value using the given key.

来源：https://stackoverflow.com/questions/8782765/how-to-put-extras-to-different-activity