我遇到了CheckBox问题。那么两个问题。
我的应用程序有一个ListView的联系人姓名（从android内置联系人列表中检索）和复选框。此外，用户可以在列表中多选名称
我在一个班级里有2个班级
1. public class ContactsList
2。public class MyCustomAdapter
以下是我的代码： ContactsList.java - 更新我的代码
公共类ContactsList扩展了ListActivity { static ArrayList friendsList = new ArrayList（）;
ListView list;
private ContactsList[] friends;
private ArrayAdapter<ContactsList> listAdapter;
final Context context = this;
Cursor cursor;
String[] buddiesList =
{"Kanak Priya",
"Joanne Liew",
"Michelle Lam",
"Teo Kin Hua",
"Melissa Haiting",
"David Yeo",
"Natasha Akhbar",
"Gillian Gan",
"Sonia",
"Ms Long",
"Joan Tang",
"Stephanie",
"Nur Ashiqin"
};
BuddyDBAdapter buddyDB = new BuddyDBAdapter(this);
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
//setListAdapter(new MyCustomAdapter(ContactsList.this, R.layout.contacts_list, buddiesList));
setContentView(R.layout.contacts_list);
setListAdapter(new ArrayAdapter<String>(this, R.layout.contacts_list, buddiesList));
ListView list = (ListView) findViewById(android.R.id.list);
//ListView list = getListView();
list.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id)
{
ContactsList friends = listAdapter.getItem(position);
friends.**toggleChecked**();
ContactsListViewHolder viewHolder = (ContactsListViewHolder) view.getTag();
viewHolder.**getCheckBox**().setChecked(friends.**isChecked**());
Cursor cursor = null;
cursor = (Cursor) parent.getItemAtPosition(position);
Intent intent = new Intent(ContactsList.this, Create_Events.class);
intent.putExtra("name", cursor.getString(cursor.getColumnIndex(buddyDB.KEY_NAME)));
startActivity(intent);
}
});
ContactsList[] arrContacts = friendsList.toArray(new ContactsList[0]);
Uri allContacts = Uri.parse("content://contacts/people");
Cursor c = managedQuery(allContacts, null, null, null, null);
String[] columns = new String[] {ContactsContract.Contacts.DISPLAY_NAME};
int[] views = new int[] {R.id.contactName};
startManagingCursor(c);
SimpleCursorAdapter friendsAdapter = new SimpleCursorAdapter(this, R.layout.contacts_list, c, columns, views);
this.setListAdapter(friendsAdapter);
}
private static class ContactsName
{
private String name = "";
private boolean checked = false;
public ContactsName(String name)
{
this.name = name;
}
public String getName()
{
return name;
}
public boolean isChecked()
{
return checked;
}
public void setChecked(boolean checked)
{
this.checked = checked;
}
public String toString()
{
return name;
}
public void toggleChecked()
{
checked = !checked;
}
}
private static class ContactsListViewHolder
{
private CheckBox nameCheck;
private TextView contactName;
public ContactsListViewHolder(TextView contactName, CheckBox nameCheck)
{
this.nameCheck = nameCheck;
this.contactName = contactName;
}
public CheckBox getNameCheck()
{
return nameCheck;
}
public TextView getContactName()
{
return contactName;
}
}
private static class ContactsCustomAdapter extends ArrayAdapter<ContactsList>
{
private LayoutInflater inflater;
public ContactsCustomAdapter(Context context, List<ContactsList> friendsList)
{
**super(context, R.layout.contacts_list, R.id.contactName, R.id.contactCheckbox, friendsList);**
inflater = LayoutInflater.from(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent)
{
ContactsList friends = (ContactsList) this.getItem(position);
CheckBox nameCheck;
TextView contactName;
if(convertView == null)
{
convertView = inflater.inflate(R.layout.contacts_list, null);
contactName = (TextView) convertView.findViewById(R.id.contactName);
nameCheck = (CheckBox) convertView.findViewById(R.id.contactCheckbox);
convertView.setTag(new ContactsListViewHolder(contactName, nameCheck));
nameCheck.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
CheckBox cb = (CheckBox) v;
ContactsList friends = (ContactsList) cb.getTag();
friends.**setChecked**(cb.isChecked());
if(cb.isChecked())
{
friendsList.add(friends.**name**);
}
else
{
friendsList.remove(friends.**name**);
}
}
});
}
else
{
ContactsListViewHolder viewHolder = (ContactsListViewHolder) convertView.getTag();
nameCheck = viewHolder.**getCheckBox**();
contactName = viewHolder.**getTexView**();
}
}
}
@Override
public void onListItemClick(ListView l, View v, int position, long id)
{
buddyDB.open();
long name_id;
super.onListItemClick(l, v, position, id);
Cursor cursor = null;
cursor = (Cursor) l.getItemAtPosition(position);
Intent intent = new Intent(ContactsList.this, Create_Events.class);
intent.putExtra("name", cursor.getString(cursor.getColumnIndex(buddyDB.KEY_NAME)));
startActivity(intent);
ListView list = getListView();
list.setChoiceMode(2);
list.setTextFilterEnabled(true);
l.setItemChecked(position, l.isItemChecked(position));
Cursor c = ((SimpleCursorAdapter)l.getAdapter()).getCursor();
c.moveToPosition(position);
TextView contactName = (TextView) v.findViewById(R.id.contactName);
String NameValue = contactName.getText().toString();
name_id = buddyDB.insertNames(NameValue);
Toast.makeText(getBaseContext(),
"Selected: " + buddiesList[position], Toast.LENGTH_SHORT).show();
buddyDB.close();
}
}
注意
我大胆的代码意味着那些是我得到的错误。它要求isChecked(), toggleChecked(), setChecked() and getCheckBox()的创建方法。
要求为name创建字段类型或常量类型，但我已经创建了它
private static class ContactsName
{
private String name = "";
我不确定我编码错误的地方。我需要能够将名称插入数据库表，我想确保当我检查名称时，不应检查其他名称。有人可以帮帮我吗？ 谢谢！ =）
答案 0 :(得分：0)
以下以Planet名称为例，只需将字符串更改为联系人姓名：
public class PlanetsActivity extends Activity {
static ArrayList<String> FavList = new ArrayList<String>();
private ListView mainListView ;
private Planet[] planets ;
private ArrayAdapter<Planet> listAdapter ;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main2);
// Find the ListView resource.
mainListView = (ListView) findViewById( R.id.mainListView );
// When item is tapped, toggle checked properties of CheckBox and Planet.
mainListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick( AdapterView<?> parent, View item,
int position, long id) {
Planet planet = listAdapter.getItem( position );
planet.toggleChecked();
PlanetViewHolder viewHolder = (PlanetViewHolder) item.getTag();
viewHolder.getCheckBox().setChecked( planet.isChecked() );
}
});
// Create and populate planets.
planets = (Planet[]) getLastNonConfigurationInstance() ;
if ( planets == null ) {
planets = new Planet[] {
new Planet("Mercury"), new Planet("Venus"), new Planet("Earth"),
new Planet("Mars"), new Planet("Jupiter"), new Planet("Saturn"),
new Planet("Uranus"), new Planet("Neptune"), new Planet("Ceres"),
new Planet("Pluto"), new Planet("Haumea"), new Planet("Makemake"),
new Planet("Eris")
};
}
ArrayList<Planet> planetList = new ArrayList<Planet>();
planetList.addAll( Arrays.asList(planets) );
// Set our custom array adapter as the ListView's adapter.
listAdapter = new PlanetArrayAdapter(this, planetList);
mainListView.setAdapter( listAdapter );
}
/** Holds planet data. */
private static class Planet {
private String name = "" ;
private boolean checked = false ;
public Planet( String name ) {
this.name = name ;
}
public String getName() {
return name;
}
public boolean isChecked() {
return checked;
}
public void setChecked(boolean checked) {
this.checked = checked;
}
public String toString() {
return name ;
}
public void toggleChecked() {
checked = !checked ;
}
}
/** Holds child views for one row. */
private static class PlanetViewHolder {
private CheckBox checkBox ;
private TextView textView ;
public PlanetViewHolder( TextView textView, CheckBox checkBox ) {
this.checkBox = checkBox ;
this.textView = textView ;
}
public CheckBox getCheckBox() {
return checkBox;
}
public TextView getTextView() {
return textView;
}
}
/** Custom adapter for displaying an array of Planet objects. */
private static class PlanetArrayAdapter extends ArrayAdapter<Planet> {
private LayoutInflater inflater;
public PlanetArrayAdapter( Context context, List<Planet> planetList ) {
super( context, R.layout.simplerow, R.id.rowTextView, planetList );
// Cache the LayoutInflate to avoid asking for a new one each time.
inflater = LayoutInflater.from(context) ;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// Planet to display
Planet planet = (Planet) this.getItem( position );
// The child views in each row.
CheckBox checkBox ;
TextView textView ;
// Create a new row view
if ( convertView == null ) {
convertView = inflater.inflate(R.layout.simplerow, null);
// Find the child views.
textView = (TextView) convertView.findViewById( R.id.rowTextView );
checkBox = (CheckBox) convertView.findViewById( R.id.CheckBox01 );
// Optimization: Tag the row with it's child views, so we don't have to
// call findViewById() later when we reuse the row.
convertView.setTag( new PlanetViewHolder(textView,checkBox) );
// If CheckBox is toggled, update the planet it is tagged with.
checkBox.setOnClickListener( new View.OnClickListener() {
public void onClick(View v) {
CheckBox cb = (CheckBox) v ;
Planet planet = (Planet) cb.getTag();
planet.setChecked( cb.isChecked() );
if (cb.isChecked()){
FavList.add(planet.name);
}
else{
FavList.remove(planet.name);
}
}
});
}
// Reuse existing row view
else {
// Because we use a ViewHolder, we avoid having to call findViewById().
PlanetViewHolder viewHolder = (PlanetViewHolder) convertView.getTag();
checkBox = viewHolder.getCheckBox() ;
textView = viewHolder.getTextView() ;
}
// Tag the CheckBox with the Planet it is displaying, so that we can
// access the planet in onClick() when the CheckBox is toggled.
checkBox.setTag( planet );
// Display planet data
checkBox.setChecked( planet.isChecked() );
textView.setText( planet.getName() );
return convertView;
}
}
public Object onRetainNonConfigurationInstance() {
return planets ;
}
public void comments (View view) {
Intent myintent = new Intent (getApplicationContext(), DB.class);
myintent.putExtra("name", FavList);
startActivity(myintent);
}
}
DB.class看起来像：
public class DB extends ListActivity {
private final String SAMPLE_DB_NAME = "myFriendsDb";
private final String SAMPLE_TABLE_NAME = "friend";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ArrayList<String> NumList = getIntent().getStringArrayListExtra("name");
ArrayList<String> results = new ArrayList<String>();
SQLiteDatabase sampleDB = null;
try {
sampleDB = this.openOrCreateDatabase(SAMPLE_DB_NAME, MODE_PRIVATE, null);
sampleDB.execSQL("CREATE TABLE IF NOT EXISTS " +
SAMPLE_TABLE_NAME +
" (FirstName VARCHAR);");
for(String str: NumList){
sampleDB.execSQL("INSERT INTO " +
SAMPLE_TABLE_NAME +
" ( FirstName ) Values ('"+str+"');");
}
Cursor c = sampleDB.rawQuery("SELECT FirstName FROM " +
SAMPLE_TABLE_NAME +
" where FirstName > 10 LIMIT 5", null);
if (c != null ) {
if (c.moveToFirst()) {
do {
String firstName = c.getString(c.getColumnIndex("FirstName"));
results.add("" + firstName);
}while (c.moveToNext());
}
}
this.setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,results));
} catch (SQLiteException se ) {
Log.e(getClass().getSimpleName(), "Could not create or Open the database");
} finally {
if (sampleDB != null)
sampleDB.execSQL("DELETE FROM " + SAMPLE_TABLE_NAME);
sampleDB.close();
}
}
}