如何在列表视图中显示项目的文本Android Studio

Question

I'm having a lot of trouble figuring this out. What I want to do is display a different description depending on which item I click from a list view. Let's say I choose the third recipe on the list. It should switch to another activity and show the description for that recipe only and not any other recipe. I have the descriptions in the strings folder.

In my code, it has a listener and an intent to open the other activity. When I run the app, once I click on the item on the list, it closes. Before, I did not use a listener, but a method and have an onClick for the textview and image view in the xml. That would switch the activity, but would not show any description.

public class MainActivity extends AppCompatActivity {                                           
private RecipesDataSource ds;                                                               
private ListView recipesListView;                                                           

@Override                                                                                   
protected void onCreate(Bundle savedInstanceState) {                                        
    super.onCreate(savedInstanceState);                                                     
    setContentView(R.layout.activity_main);                                                 
    ds = new RecipesDataSource();                                                           
    recipesListView = (ListView)findViewById(R.id.listView1);                               
    recipesListView.setAdapter(new RecipesDataSourceAdapter(this,ds));                      
    recipesListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {          
        @Override                                                                           
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {  
            Intent i = new Intent(MainActivity.this, RecipesInfoActivity.class);            
            i.putExtra("recipe_desc", position);                                            
            startActivity(i);                                                               
        }                                                                                   
    });                                                                                     
}                                                                                           

}                                           

Here is the second activity where I want the description to appear. It has a text view for holding the text.

public class RecipesInfoActivity extends AppCompatActivity {
TextView recipeInfo;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_recipes_info);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });

    recipeInfo = (TextView)findViewById(R.id.recipeInfoTextView);
    Intent i = getIntent();
    String pos = i.getStringExtra("recipe_desc");
    recipeInfo.setText(writeDesc(pos));
}

public int writeDesc(String pos)
{
    int position = Integer.parseInt(pos);
    int desc = 0;
    if(position==0)
    {
        desc = R.string.description1;
    }
    else if(position==1)
    {
        desc = R.string.description2;
    }
    else if(position==2)
    {
        desc = R.string.description3;
    }
    else if(position==3)
    {
        desc = R.string.description4;
    }
    else if(position==4)
    {
        desc = R.string.description5;
    }
    else if(position==5)
    {
        desc = R.string.description6;
    }
    else if(position==6)
    {
        desc = R.string.description7;
    }
    return desc;
}

}                                                    

The method writeDesc() returns the description depending on the position that putExtra() passes from the MainActivity . The variables are ints because I'm using an ArrayList with Integers.

Please don't give me complicated code since I'm new to Android Studio. If you have a solution to offer, please make as simple as possible.

Summary of what I need help with:

-Writes a description on a second activity depending on which item is clicked from a listview. Ex: If I click on a recipe for chicken, it will show the recipe for chicken(I have these descriptions as strings, so you don't need to worry about that.)

-Should I use the listener or a separate method that is called when the item is clicked from the listview(uses android:onClick="whatevermethodnamehere" in xml instead of how it is now in the main activity with a listener). Listener, for some reason, does not switch to the next activity and crashes, but the onClick does not crash and switches, but no description is shown.

Answer 1

Why not have the writeDesc method return a STRING of the description instead of an integer. Looks to me like you are just returning int values...

Answer 2

Since you have already figured out the difficult part ie using ItemClickListener , I believe you just need some direction, so here it is.

Based upon position, put different text in your intent.putExtra

eg instead of i.putExtra("recipe_desc", position); use this i.putExtra("key","recipe_desc");

Now it is upto you how you wish to do it. I have 2 flavors as quick suggestions Flavor1: Make a mapper class that maps recipe_desc with proper descriptions. eg if you receive "chicken" in your recipe_desc , then this mapper class contain chicken receipe mapped to it. In activitB , simply use switch-case for get the correct value

Flavor2: instead of using mapper class in activityB, directly put the description into your intent.extra based upon position. Now just display whatever you get from intent. So in flavor2 your switch-case moves to activityA