在ListView中使用带有文本和图像的MatrixCursor和SimpleCursorAdapter

Question

我有一个问题,使用MatrixCursor填充我的ListView:

private void fillData() {
    String[] menuCols = new String[] { "icon", "item", "price" };
    int[] to = new int[] { R.id.icon, R.id.item, R.id.price };

    MatrixCursor menuCursor = new MatrixCursor(menuCols);
    startManagingCursor(menuCursor);

    menuCursor.addRow(new Object[] { R.drawable.chicken_sandwich, "Chicken Sandwich", "$3.99" });

    SimpleCursorAdapter menuItems = new SimpleCursorAdapter(
            this, R.layout.menu_row, menuCursor, menuCols, to);

    setListAdapter(menuItems);
}

构造SimpleCursorAdapter崩溃的原因.即使我尝试删除图标,应用程序仍然崩溃.这是我的menu_row.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    xmlns:android="http://schemas.android.com/apk/res/android">
    <ImageView 
        android:id="@+id/icon"
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content">
    </ImageView>
    <TextView 
        android:id="@+id/item" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content">
    </TextView>
    <TextView 
        android:id="@+id/price" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content">
    </TextView>
</LinearLayout>

编辑:这是崩溃时的调用堆栈:

Thread [<3> main] (Suspended (exception RuntimeException))  
    ActivityThread.performLaunchActivity(ActivityThread$ActivityRecord, Intent) line: 2481  
    ActivityThread.handleLaunchActivity(ActivityThread$ActivityRecord, Intent) line: 2497   
    ActivityThread.access$2200(ActivityThread, ActivityThread$ActivityRecord, Intent) line: 119 
    ActivityThread$H.handleMessage(Message) line: 1848  
    ActivityThread$H(Handler).dispatchMessage(Message) line: 99 
    Looper.loop() line: 123 
    ActivityThread.main(String[]) line: 4338    
    Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]  
    Method.invoke(Object, Object...) line: 521  
    ZygoteInit$MethodAndArgsCaller.run() line: 860  
    ZygoteInit.main(String[]) line: 618 
    NativeStart.main(String[]) line: not available [native method]  

解:

我发现了问题,解决方案在我的答案中.

Answer 1

让我们来讨论使用Eclipse调试Java的经验.

在调试器中运行应用程序,我遇到了RuntimeException崩溃.单击调用堆栈中的顶部元素给了我变量列表,我在其中看到了我的异常e.

特定错误是InvalidArgument,因为我的MatrixCursor没有_id列.添加标记为_id的列可以解决问题,现在一切正常.

感谢您让我再次查看调试器!熟悉并熟悉您的工具!