menuitem.getmenuinfo（）对于动态创建的视图返回null

Question

I have a ScrollView with an embedded RelativeLayout with an embedded LinearLayout .

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent">

    <RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"
        android:paddingLeft="16dp" android:paddingRight="16dp" android:id="@+id/relativeLayout">

        <LinearLayout
            android:orientation="vertical"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" android:layout_below="@+id/Today"
            android:layout_alignParentLeft="true" android:id="@+id/linearLayoutToday"
            android:animateLayoutChanges="true">
        </LinearLayout>

    </RelativeLayout>

</ScrollView>

I want to add a context menu for CheckBox objects, which are added dynamically as shown below.

private void addItem() {
    CheckBox ch = new CheckBox(this);
    ch.setText("Test");
    registerForContextMenu(ch);
    linearLayoutToday.addView(ch);
}

The issue occurs in the onContextItemSelected method, as the value returned from item.getMenuInfo() is always null.

@Override
public boolean onContextItemSelected(MenuItem item) {
    AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
    System.out.println(info.targetView);
    return true;
}

Does anyone know how to resolve this issue?

Answer 1

This problem was caused because to add a context menu to all children, you simply add a context menu to the parent. However, this is only supported with other views (eg ListView), not layouts.