使用上下文菜单在自定义列表视图中突出显示所选项目?

highlighting selected item in custom list view using context menu?

我一直在尝试在此列表视图上设置我的背景颜色,并且在遵循多个教程后它没有出现,但没有显示任何错误。

我得到的是在值文件夹中名为 colors 的 xml 文件:

<resources>
    <drawable name="red_colour">#6D0E0E</drawable>
</resources>

链接到可绘制文件夹中的 xml:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
    android:state_pressed="true"
    android:state_activated="true"
    android:drawable="@drawable/red_colour">
</item>

</selector>

我试过放置以下代码 android:background:@id"colourhighlight.xml" 根据各种教程几乎无处不在,但没有运气?

有什么建议吗?请帮忙...

我有一个带上下文菜单的主 class:

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

        // The contacts from the contacts content provider is stored in this cursor
        mMatrixCursor = new MatrixCursor(new String[] { "_id","name","photo","details"} );

        // Adapter to set data in the listview
        mAdapter = new SimpleCursorAdapter(getBaseContext(),
                R.layout.lv_layout,
                null,
                new String[] { "name","photo","details"},
                new int[] { R.id.tv_name,R.id.iv_photo,R.id.tv_details}, 0);

        // Getting reference to listview
        final ListView lstContacts = (ListView) findViewById(R.id.lst_contacts);

        // Setting the adapter to listview
        lstContacts.setAdapter(mAdapter);

        // Creating an AsyncTask object to retrieve and load listview with contacts
        ListViewContactsLoader listViewContactsLoader = new ListViewContactsLoader();

        // Starting the AsyncTask process to retrieve and load listview with contacts
        listViewContactsLoader.execute();

        //Selecting and highlighting the elements in the listview
        lstContacts.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                view.setActivated(true);
            }
        });

        //Creating the context menu and the options for it
        listview = (ListView) findViewById(R.id.lst_contacts);
        listview.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE_MODAL);
        listview.setMultiChoiceModeListener(new AbsListView.MultiChoiceModeListener() {
            @Override
            public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) {
                count = count+1;
                mode.setTitle(count + " Contacts Selected");


            }

            @Override
            public boolean onCreateActionMode(ActionMode mode, Menu menu) {

                MenuInflater inflater = mode.getMenuInflater();
                inflater.inflate(R.menu.contact_context_menu, menu);

                return true;
            }

            @Override
            public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            @Override
            public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                switch(item.getItemId()){
                    case R.id.delete_id:
                        Toast.makeText(getBaseContext(), count + " Contacts Deselected", Toast.LENGTH_SHORT).show();
                        count = 0;
                        mode.finish();
                        return true;
                        //break;
                    default:
                       return false; //break;
                }

                //return false;
            }

            @Override
            public void onDestroyActionMode(ActionMode mode) {

            }
        });

    }

lv_layout.xml

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

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/iv_photo"
        android:maxHeight="80dp"
        android:maxWidth="80dp"
        android:adjustViewBounds="true"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:id="@+id/tv_name"
        android:layout_alignParentTop="true"
        android:layout_toRightOf="@+id/iv_photo"
        android:layout_toEndOf="@+id/iv_photo" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceSmall"
        android:id="@+id/tv_details"
        android:layout_below="@+id/tv_name"
        android:layout_toRightOf="@+id/iv_photo"
        android:layout_toEndOf="@+id/iv_photo" />
</RelativeLayout>

主要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" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context="com.example.ankhit.saveme.UserContacts"
    android:background="@drawable/colourhighlight"
    >

    <ListView
        android:id="@+id/lst_contacts"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/button"
        />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/instructions"
        android:id="@+id/button"
        android:onClick="showInstructions"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true" />

</RelativeLayout>
@Override
public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) 
{
    try 
    {
        final int checkedCount = listView.getCheckedItemCount();
        mode.setTitle(""+checkedCount);

        if (checked)
        {
            adapter.setNewSelection(position, checked);                    
        }
        else 
        {
            adapter.removeSelection(position);                 
        }
        adapter.notifyDataSetChanged();
    }
    catch (Exception e) 
    {
        e.printStackTrace();
    }
}

在您的适配器中添加这些方法class

private HashMap<Integer, Boolean> mSelection = new HashMap<Integer, Boolean>();
public void setNewSelection(int position, boolean value) 
{
    mSelection.put(position, value);
}

public boolean isPositionChecked(int position) 
{
    Boolean result = mSelection.get(position);
    return result == null ? false : result;
}

public Set<Integer> getCurrentCheckedPosition() {
    return mSelection.keySet();
}

public void removeSelection(int position) {
    mSelection.remove(position);
}

public void clearSelection() {
    mSelection = new HashMap<Integer, Boolean>();
}

在适配器的 getView() 方法中调用此方法它可以正常工作

convertView.setBackgroundColor(mContext.getResources().getColor(android.R.color.transparent));
if (mSelection.get(position) != null) 
{
    convertView.setBackgroundColor(mContext.getResources().getColor(R.color.message_selector_holo_blue));
                }

如果要完全突出显示所选行,请更改转换视图的背景颜色

lstContacts.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            view.setBackgroundColor(mContext.getResources().getColor(android.R.color.transparent));


        }
    });