Question

最终，我想点击ListView中的一个项目（最终是一个回收者列表视图）并让它将一个id传输到下一个活动，以便从db中进行检索。

我有一个ListView，由CursorAdapter（子类）提供。当我在CursorAdapter.bindView（）中设置断点时，传入的View的类型为TwoItemListItem，所以我无法在RecipeListItem上设置id，我相信我需要做的就是通过ListView将信息传递给下一个活动.setOnItemClickListener（）。

在源活动中，我获取列表视图并设置适配器：

        RecipeCursorAdapter adapter = new RecipeCursorAdapter(this, cur);

        ListView listView = (ListView) findViewById(R.id.recipe_list_list);
        listView.setAdapter(adapter);

RecipeCursorAdapter：

public class RecipeCursorAdapter extends CursorAdapter {
    protected LayoutInflater cursorInflator;

    public RecipeCursorAdapter(Context context, Cursor cursor){
        super(context, cursor, 0);
        this.cursorInflator = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    // The newView method is used to inflate a new view and return it,
    // you don't bind any data to the view at this point.
    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent){
        return this.cursorInflator.inflate(R.layout.activity_recipe_list_item, parent, false);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor){
        // Find fields to populate in inflated template
        TextView tvTitle = (TextView) view.findViewById(R.id.recipeListItemTitle);
        TextView tvSubtitle = (TextView) view.findViewById(R.id.recipeListItemSubtitle);

        // Extract properties from cursor
        String name = cursor.getString(cursor.getColumnIndexOrThrow("name"));
        String description = cursor.getString(cursor.getColumnIndexOrThrow("description"));

        // Populate fields with extracted properties
        tvTitle.setText(name);
        tvSubtitle.setText(description);
    }
}

activity_recip_list_item.xml：

<?xml version="1.0" encoding="utf-8"?>
<TwoLineListItem xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:minHeight="?attr/listPreferredItemHeight"
    android:mode="twoLine"
    android:orientation="horizontal"
    tools:context="com.smadacm.reciperepo.RecipeListItem" >
    <TextView
        android:id="@+id/recipeListItemTitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge" />
    <TextView
        android:id="@+id/recipeListItemSubtitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="10dp"
        android:layout_below="@id/recipeListItemTitle"
        android:layout_alignStart="@id/recipeListItemTitle"
        android:textColor="@color/colorListSecondary"
        android:textAppearance="?android:attr/textAppearanceListItemSecondary" />
</TwoLineListItem>

RecipeListItem：

public class RecipeListItem extends AppCompatActivity {
    protected int itemId;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recipe_list_item);
    }

    public void setItemId(int id){
        this.itemId = id;
    }
    public int getItemId(){
        return this.itemId;
    }
}

Answer 1

我能够绊倒一些功能性的东西。我不知道这是否正确，我可以接受纠正。

在我的主要活动中，我添加了一个听众：

        RecipeCursorAdapter adapter = new RecipeCursorAdapter(this, cur);

        ListView listView = (ListView) findViewById(R.id.recipe_list_list);
        listView.setAdapter(adapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                int ii = 0; // A line on which I can set a breakpoint
            }
        });

我添加了一个新类来扩展LinearLayout。这主要是调用超类，但也添加了设置和检索任意数据的方法：

public class RecipeListItem extends LinearLayout {
    protected int recipeId;

    public RecipeListItem(Context context) {
        super(context, (AttributeSet)null, 0, 0);
    }

    public RecipeListItem(Context context, AttributeSet attrs) {
        super(context, attrs, 0, 0);
    }

    public RecipeListItem(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr, 0);
    }

    public RecipeListItem(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public void setRecipeId(int id){
        this.recipeId = id;
    }
    public int getRecipeId(){
        return this.recipeId;
    }
}

我使用LinearLayout子类来定义列表项：

<com.smadacm.reciperepo.widget.RecipeListItem xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    tools:context="com.smadacm.reciperepo.RecipeListItem" >
    <TextView
        android:id="@+id/recipeListItemTitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge" />
    <TextView
        android:id="@+id/recipeListItemSubtitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="10dp"
        android:layout_below="@id/recipeListItemTitle"
        android:layout_alignStart="@id/recipeListItemTitle"
        android:textColor="@color/colorListSecondary"
        android:textAppearance="?android:attr/textAppearanceListItemSecondary" />
</com.smadacm.reciperepo.widget.RecipeListItem>

最后，在我的CursorAdapter中，我按项设置id：

@Override
public void bindView(View viewRaw, Context context, Cursor cursor){
    RecipeListItem view = (RecipeListItem) viewRaw;
    // Find fields to populate in inflated template
    TextView tvTitle = (TextView) view.findViewById(R.id.recipeListItemTitle);
    TextView tvSubtitle = (TextView) view.findViewById(R.id.recipeListItemSubtitle);

    // Extract properties from cursor
    String name = cursor.getString(cursor.getColumnIndexOrThrow("name"));
    String description = cursor.getString(cursor.getColumnIndexOrThrow("description"));
    int id = cursor.getInt(cursor.getColumnIndexOrThrow("_id"));

    // Populate fields with extracted properties
    tvTitle.setText(name);
    tvSubtitle.setText(description);

    view.setRecipeId(id);
}

将数据存储在列表项

1 个答案: