如何将String从2个活动传递到一个活动？

Question

I have two activitys with lists.

One for tablet's and one for regular density phones. When an item in the list is clicked it launches the same activity for either activity with list's.

The problem is when an item is clicked i have getter and setter class that gets the URL for a particular item and passes it to the launching activity like this...

    private String URL = null;
try{
        URL = com.fttech.AbstractFeedsActivity.feed_url;

    }
    catch(IllegalArgumentException e){
        e.printStackTrace();
        URL = com.fttech.ItemsActivity.url;

    }

As you see what i tried to do is try and catch. So if the first one isnt found then the second one will be retrieved.

But it doesnt seem to work.

It returns null each time.

For what i have describe what is the best way to implement this? Is my way logic? Or is there a better way.

Thanks

Answer 1

Try this,

     private String URL = null;
     try{
            URL = com.fttech.AbstractFeedsActivity.feed_url;
            if(TextUtils.isEmpty(URL)){
                 URL = com.fttech.ItemsActivity.url;
                 // Pass this URL   
            }
            else{
              // If its not empty then it will pass the first URL
          }
        }
        catch(IllegalArgumentException e){
            e.printStackTrace();
        }

Answer 2

无需将String传递给2个活动，如果您只想将字符串传递给一个或任意多个活动，只需将它们放在SharedPreferences中或在静态类中声明一个变量，然后在需要时进行设置/获取即可。

Answer 3

Passing values from one Activity to another:

Intent intent = new Intent(context, CalledActivity.class);
intent.putExtra(key, value);
startActivity(intent);

If you want some data back from called Activity then you can use startActivityForResult() as:

Intent intent = new Intent(context, CalledActivity.class);
intent.putExtra(key, value);
startActivityForResult(intent, requestCode);

In called activity you can set data as:

setResult(RESULT_OK, intent);

Note: Here you set the value in intent and pass it to setResult().

On returning back to calling Activity you can get data by overriding:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(resultCode == RESULT_OK){
        //Get data from Intent "data" and do your task here....
    }
}

Note: You can pass primitive data type values thru Intent and if you want to pass other types then you have to use Bundle like this.

Bundle data = new Bundle();
data.putIntArray(key, value);

//same way you can set other values....... //Now set this Bundle value to Intent as you do for primitive type....

Intent intent = new Intent(context, CalledActivity.class);
intent.putExtra(data);
startActivity(intent);

Receiving data in Activity:

//For primitive values:

DataType var_name = getIntent().getExtras().get(key);

//For Bundle values:

Bundle var_name = getIntent().getExtras().getBundle(key);