android - 如何链接填充 ListView 中每个联系人的复选框？

Question

这个问题一直困扰着我。我有一个 ListView ，其中包含:

ImageView/contactName/TextView/CheckBox

ListView 中的 contactName 是通过从 SimpleCursorAdapter 读取手机上的联系人来填充的。所有 for 元素都会在应用程序运行时显示，但我遇到的问题是将复选框连接到列表中的相应项目。

通过一些研究，我发现我必须使用 getView() 将复选框与列表中的项目链接起来，但通过实践，我似乎无法让它正常工作.此外，我试过的所有示例都没有真正解释如何应用 getView()。我一直在使用的最完整的示例来自这里:

http://androidcocktail.blogspot.com/2012/04/adding-checkboxes-to-custom-listview-in.html

不同之处在于，这会读取我的联系人 ListView 并将其填充到 ListView 中:

private void populateContactList() {
    // Build adapter with contact entries
    Cursor cursor = getContacts();
    String[] fields = new String[] {
            ContactsContract.Data.DISPLAY_NAME       
    };

    SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.contact_entry, cursor,
            fields, new int[] {R.id.contactEntryText});    
    lv.setAdapter(adapter);        
} // END POPULATECONTACTLIST


private Cursor getContacts()
{ 
    // Run query
    Uri uri = ContactsContract.Contacts.CONTENT_URI;
    String[] projection = new String[] {
            ContactsContract.Contacts._ID,
            ContactsContract.Contacts.DISPLAY_NAME
    };
    String selection = ContactsContract.Contacts.IN_VISIBLE_GROUP + " = '" +
            (chkboxAllVisible ? "0" : "1") + "'";
    String[] selectionArgs = null;
    String sortOrder = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC";

    return managedQuery(uri, projection, selection, selectionArgs, sortOrder);
} // END GETCONTACTS 

如何将每个复选框链接到 ListView 中相应的联系人项目？

Answer 1

好的，我已经为您创建了一个测试项目，如果您遇到任何问题，请尝试理解代码，然后问我，我会尽力帮助您...

这是我创建的 Activity 函数。

super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ArrayList<String> elements = new ArrayList<String>();
for (int i = 0; i < 10; i++) {
    elements.add("elements " + i);
}

CheckBox master_cb = new CheckBox(getApplicationContext());
master_cb.setText("Check All");
//HERE IS THE LIST VIEW WHICH I HAVE CREATED IN MY XML FILE.
ListView lv = (ListView) findViewById(R.id.listView1);
//HERE I AM CREATING CUSTOM ADAPTER OBJECT.
my_custom_adapter adapter = new my_custom_adapter(this, android.R.layout.simple_list_item_1, elements);
lv.addHeaderView(master_cb);
lv.setAdapter(adapter);
master_cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
        Intent my_intent = new Intent("master_check_change");
        my_intent.putExtra("check_value", isChecked);
        sendBroadcast(my_intent);
    }
});

这是我的自定义适配器。

public class my_custom_adapter extends ArrayAdapter<String> {
    private Context context                     = null;
    ArrayList<String>  elements                 = null;
    private ArrayList<Boolean> itemChecked      = null;

    public my_custom_adapter(Context context, int type, ArrayList<String>  elements)
    {
        super(context, type, elements);
        this.elements =  elements;
        this.context = context;
        itemChecked = new ArrayList<Boolean>();
        BroadcastReceiver receiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                if (intent.getAction().equals("master_check_change")) {
                    boolean check_value = intent.getBooleanExtra("check_value", false);
                    set_checked(check_value);
                    notifyDataSetChanged();
                }
            }
        };
        context.registerReceiver(receiver, new IntentFilter("master_check_change"));
        set_checked(false);
    }

    // AS EVERY TIME LISTVIEW INFLATE YOUR VIEWS WHEN YOU MOVE THEM SO YOU NEED TO SAVE ALL OF YOUR CHECKBOX STATES IN SOME ARRAYLIST OTHERWISE IT WILL SET ANY DEFAULT VALUE.
    private void set_checked(boolean is_checked)
    {
        for (int i=0; i < elements.size(); i++) {
            itemChecked.add(i, is_checked);
        }
    }

    //THIS IS SIMPLY A CLASS VIEW WILL HOLD DIFFERENT VIEWS OF YOUR ROW.
    static class ViewHolder
    {
        public TextView tv;
        public CheckBox cb;
        public ImageView iv;
    }

    @Override
    public View getView (final int position, View convertView, ViewGroup parent)
    {
        View rowView = convertView;
        ViewHolder holder = null;

        if (rowView == null) {
            LayoutInflater inflater = (LayoutInflater)context.getSystemService(
                                               Context.LAYOUT_INFLATER_SERVICE);
            // HERE I AM INFLATING LISTVIEW LAYOUT.
            rowView = inflater.inflate(R.layout.inflated_layout, null, false);
            holder = new ViewHolder();
            holder.cb = (CheckBox) rowView.findViewById(R.id.checkBox1);
            holder.tv = (TextView) rowView.findViewById(R.id.textView1);
            holder.iv = (ImageView) rowView.findViewById(R.id.imageView1);
            rowView.setTag(holder);

        } else {
            holder = (ViewHolder) rowView.getTag();
        }

        if (holder != null) {
            holder.tv.setText(elements.get(position));

            holder.cb.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                @Override
                public void onCheckedChanged(CompoundButton buttonView,
                                             boolean isChecked) {
                    itemChecked.set(position, isChecked);
                }
            });

            if(position < itemChecked.size()) {
                holder.cb.setChecked(itemChecked.get(position));
            }
        }
        return rowView;
    }
}

main.xml 文件是这样的:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >


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

    </ListView>

</RelativeLayout>

inflated_layout 代码是:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <CheckBox
        android:id="@+id/checkBox1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="17dp" />




    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_toLeftOf="@+id/checkBox1"
        android:layout_toRightOf="@+id/imageView1"
        android:singleLine="true"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />


    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:src="@drawable/ic_launcher" />

</RelativeLayout>

如果你想使用字符串数组而不是数组列表，那么替换

    String[] elements = new String[10];
    for (int i = 0; i < 10; i++) {
        elements[i] = "elements " + i;
    }

//在您的自定义适配器构造函数中

public my_custom_adapter(Context context, int type, String[]  elements)

还有一些相应的变化