Question

我使用bindView()方法是自定义CursorAdapter实现，以动态地将文本视图添加到列表中。

每个列表项都由list_item布局表示，其中包含来自Android Flowlayout的flow_layout布局

<!--List Item Layout-->
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:background="#FFFFFF">

    <!--Flow Layout-->
    <org.apmem.tools.layouts.FlowLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="@dimen/view_padding"
        android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:id="@+id/hash_tag_layout"
        >
    </org.apmem.tools.layouts.FlowLayout>

</LinearLayout>

每个flow_layout实例添加到list item的文本视图数反映了游标中返回的行值数。

public void bindView(View view, Context context, Cursor cursor) {

    // Flow layout wraps new views around the screen.
    FlowLayout flowLayout = (FlowLayout) view.findViewById(R.id.flow_Layout);

    // getRowValues() puts row values from cursor into an array list.
    ArrayList<> rowValues = getRowValues(cursor);

    // A new text view is created and inserted into Flow layout
    // for each value in rowValues 
    TextView tv;
    for value in rowValues {
        tv = = new TextView(ctx);
        tv.setText(value);
        flowLayout.addView(tv); 
    }

}

要重新迭代，我希望每个flow_layout实例的每个list_item内的文本视图数量反映光标返回的行值的数量。

但是，每次重新滚动列表项时，该特定项目中的文本视图数量会翻倍，而另外，绑定数据有时会在光标位置和列表项位置之间进行对称反映。我认为问题与旧文本视图的回收有关。

如何防止新文本视图堆叠到旧文本视图上？是否可以覆盖特定子视图的自定义游标适配器中的视图回收，并在它们离开屏幕时强制进行垃圾回收？

以下是自定义游标适配器

的完整实现

public class DatabaseAdapter extends CursorAdapter {

        Context ctx;

        public DatabaseAdapter(Context context, Cursor cursor, int flags) {

            super(context, cursor, 0);
            ctx = context;
        }

        public View newView(Context context, Cursor cursor, ViewGroup parent) {

            View v = LayoutInflater.from(context).inflate(R.layout.list_item, parent, false);
            return v;
        }

        public void bindView(View view, Context context, Cursor cursor) {

            // Flow layout wraps new views around the screen.
            FlowLayout flowLayout = (FlowLayout) view.findViewById(R.id.flow_Layout);

            // getRowValues() puts row values from cursor into an array list.
            ArrayList<> rowValues = getRowValues(cursor);

            // A new text view is created and inserted into Flow layout
            // for each value in rowValues array list
            TextView tv;
            for value in rowValues {
                tv = = new TextView(ctx);
                tv.setText(value);
                flowLayout.addView(tv); 
            }
        }
}

Answer 1

if(flowLayout.getChildCount() > 0)
        flowLayout.removeAllViews();

动态添加视图在光标适配器堆叠在彼此之上

1 个答案: