Android - 在onCreate中更新ListView不起作用

Question

我有以下代码：

public class MainActivity extends Activity {
    private ListView list;
    private static final String path = Environment.getExternalStorageDirectory().getPath() + File.separator + "BOE";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        list = (ListView) findViewById(R.id.listView1);
        String books[] = {"Mercedes", "Skoda", "Volkswagen", "Audi", "Citroen", "plik"};
        BookArrayAdapter bma = new BookArrayAdapter(this, books);
        bma.setNotifyOnChange(true);
        list.setAdapter(bma);
        if (!new File(path).exists()) {
            new File(path).mkdirs();
        }
        for (int i=0; i<books.length; i++) {
            View v = list.getAdapter().getView(i, null, null);
            String name = ((TextView)v.findViewById(R.id.row_text)).getText() + "";
            for (File f:new File(path).listFiles()) {
                if (f.isFile()) {
                    Button b = (Button) v.findViewById(R.id.row_button);
                    if (name.equals(f.getName().substring(0, f.getName().length()-4))) {
                        b.setText("Open");
                    } else {
                        b.setText("Download");
                    }
                    bma.notifyDataSetInvalidated();
                    bma.notifyDataSetChanged();
                    Log.d("AC", b.getText().toString());
                }
            }
        }
    }

    public class BookArrayAdapter extends ArrayAdapter<String> {
        private final Context context;
        private final String[] values;

        public BookArrayAdapter(Context context, String[] values) {
            super(context, R.layout.row, values);
            this.context = context;
            this.values = values;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            final View rowView = inflater.inflate(R.layout.row, parent, false);
            final TextView textView = (TextView) rowView.findViewById(R.id.row_text);
            textView.setText(values[position]);
            rowView.findViewById(R.id.row_button).setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (((Button)v).getText().toString().equals("Open")) {
                        //open
                    } else {
                        //Download
                    }
                }
            });
            return rowView;
        }
    }
}

我在onCreate中的for循环中遇到了问题。此日志显示正确的下载/打开文本，取决于文件系统中的文件。但是此列表视图的图形表示不会改变。这是我的layout.xml：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="${relativePackage}.${activityClass}" >

    <ListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true" >
    </ListView>

    <RelativeLayout
        android:id="@+id/main_linear_blackout"
        android:layout_width="match_parent"
        android:visibility="invisible"
        android:layout_height="match_parent"
        android:background="#CC000000" >

        <ProgressBar
            android:id="@+id/main_progress_startup"
            style="?android:attr/progressBarStyleLarge"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true" />

    </RelativeLayout>

</RelativeLayout>

和我的row.xml：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/row"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_toLeftOf="@+id/row_button"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/row_text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <ProgressBar
            android:id="@+id/row_progress"
            style="@android:style/Widget.ProgressBar.Horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:visibility="invisible" />
    </LinearLayout>

    <Button
        android:id="@+id/row_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true" />

    <TextView
        android:id="@+id/row_percentage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/row_button"
        android:layout_alignBottom="@+id/row_button"
        android:layout_alignLeft="@+id/row_button"
        android:layout_alignRight="@+id/row_button"
        android:layout_alignTop="@+id/row_button"
        android:gravity="center"
        android:textAlignment="center"
        android:textSize="20sp"
        android:visibility="invisible" />

</RelativeLayout>

如何更新？有什么问题？

修改

我将编辑单行移动到我的适配器类上的getView（...）覆盖方法。我真的不知道为什么我的第一个想法是错的，但现在它有效。