android - 如何从 contextMenu 访问 ListItem 位置

Question

我正在从事一个包含冰淇淋口味列表的项目。当您长按一种口味时，您会看到一个上下文菜单，其中包含一些选项:图片、成分、价格等。如果长按巧克力并选择图片，您应该会看到一张巧克力冰淇淋的图片...如果您对 Vanilla 做同样的操作，您会看到 Vanilla 冰淇淋。

问题来了。您在上下文菜单中所做的选择与您长按的原始 flavor 相关。我需要能够访问 flavor 数组中 flavor 的位置。 -- 在 OnListItemClicked() 方法中，我的口味数组的位置是可访问的，但是……OnContextItemSelect() 方法只知道它自己的选择项(图片、成分、价格)。

您可以看到我已经创建了一个 listPosition 变量，但我已经意识到这只有在使用 OnListItemClicked() 快速单击 flavor 而不是使用 OnContextItemSelect() 长按时才有效。

ApplyMenuChoice() 是可以找到问题代码的地方。

如果能得到帮助，我将不胜感激，谢谢:)

菜单演示.java

public class MenuDemo extends ListActivity {
    
    TextView selection;
    TextView displayText;
    String[] flavorItems;
    String[] colors;
    ImageView myImage;
    int currentMenu;
    int listPosition = 0;
    
    int[] ItemImageSource  = {R.drawable.vanilla,R.drawable.chocolate,R.drawable.strawberry};

    private final String TAG = "Main Activity";
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        selection=(TextView)findViewById(R.id.selection);
        displayText=(TextView)findViewById(R.id.displayText);
        myImage=(ImageView)findViewById(R.id.myImage);
        flavorItems = getResources().getStringArray(R.array.flavors);
        colors = getResources().getStringArray(R.array.colors);
        
        
        
        setListAdapter(new ArrayAdapter<String>(this, R.layout.flavor_menu_style, flavorItems));
        registerForContextMenu(getListView());
        displayText.setText("Welcome! Click and hold flavor to learn more about it.");
    }
    
    public void onListItemClick(ListView parent, View v,int position, long id) 
    {   
        
        if (currentMenu == 1){selection.setText(colors[position]);}
        else {selection.setText(flavorItems[position]);}
        
        String strI = Integer.toString(position);
        displayText.setText("teeesst" + strI);
        
        listPosition = position;
        Log.i(TAG,"!!!!!!!!!!!!!!");
    }
    
    @Override
    public void onCreateContextMenu(ContextMenu menu, View v,ContextMenu.ContextMenuInfo menuInfo) 
    {
        super.onCreateContextMenu(menu, v, menuInfo);
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.activity_menu_demo, menu);
    }
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu) 
    {       
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.activity_new, menu);
        
        
        return true;    
    }
    
    @Override
    public boolean onOptionsItemSelected(MenuItem item) { //item is the menu item chosen
        
        boolean ret = applyOptionMenuChoice(item);
        if ( ret == false)
            ret = super.onOptionsItemSelected(item);
        
        return ret;
            
    }
    
    
    @Override
    public boolean onContextItemSelected(MenuItem item) 
    {
        boolean ret = applyMenuChoice(item);
        if ( ret == false)
            ret = super.onContextItemSelected(item);
        
        return ret;
    }
    
     
    private boolean applyMenuChoice(MenuItem item) {
        switch (item.getItemId()) 
        {
        case R.id.picture:

        //this would work if listPosition was linked to the flavors array position
            myImage.setImageResource(ItemImageSource[listPosition]);

            return(true);
            
        case R.id.ingredients:
            
            String [] ingredients;
            ingredients = new String [3];
            
            ingredients[0] = "VANILLA -- these are the ingredients VANILLA";
            ingredients[1] = "CHOCOLATE -- these are the ingredients";
            ingredients[2] = "STRAWBERRY -- these are the ingredients";
            
            displayText.setText(ingredients[listPosition]);
            
            return(true);
            
        case R.id.order:
            //I will add stuff here later
            return(true);
        
        case R.id.price:
            //I will add stuff here later
            return(true);
        
            
        
        }

        return(false);
        
    }
    
    private boolean applyOptionMenuChoice(MenuItem item) {
        switch (item.getItemId()) 
        {
        case R.id.color_menu:
            setListAdapter(new ArrayAdapter<String>(this, R.layout.color_menu_style, colors));
            currentMenu = 1;
            return(true);
            
        case R.id.flavor_menu:
            
            setListAdapter(new ArrayAdapter<String>(this, R.layout.flavor_menu_style, flavorItems));
            currentMenu = 2;
            return(true);
        
        }

        return(false);
        
    }
    
    
}

Answer 1

您可以通过MenuItem

获取您长按的列表项的位置

    @Override
    public boolean onContextItemSelected(MenuItem item) {
         AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
         int listPosition = info.position;
         //pass this to your applyMenuChoice method. ice cream nom nom nom
    }