Android填充列表视图和从数据库填充的文本过滤器
我花了三天多的时间思考这个问题。我想创建一个从数据库填充的listview。这里的问题可能是如何将ArrayList转换为字符串[]。结果是ArrayList,SearchQueries是字符串数组Android填充列表视图和从数据库填充的文本过滤器,android,arrays,listview,text,filter,Android,Arrays,Listview,Text,Filter,我花了三天多的时间思考这个问题。我想创建一个从数据库填充的listview。这里的问题可能是如何将ArrayList转换为字符串[]。结果是ArrayList,SearchQueries是字符串数组 public class SearchActivity extends ListActivity { EditText search_box; ListView customList; private ArrayList<String> results = new ArrayLis
public class SearchActivity extends ListActivity {
EditText search_box;
ListView customList;
private ArrayList<String> results = new ArrayList<String>();
private String tableName = DatabaseHandler.TABLE_SEARCH;
private SQLiteDatabase newDB;
ArrayList<String> searched_list;
String[] SearchQueries;
@SuppressWarnings("unchecked")
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.page_search);
DatabaseHandler dbHelper = new DatabaseHandler(this.getApplicationContext());
newDB = dbHelper.getWritableDatabase();
Cursor c = newDB.rawQuery("SELECT skeys FROM " +
tableName, null);
if (c != null ) {
if (c.moveToFirst()) {
do {
String skeys = c.getString(c.getColumnIndex("skeys"));
results.add(skeys);
}while (c.moveToNext());
}
}
SearchQueries = (String[]) results.toArray();
Collections.shuffle(Arrays.asList(results));
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
getApplicationContext(), R.layout.listviews_search, SearchQueries);
customList.setAdapter(adapter);
customList.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getApplicationContext(), ((TextView) view).getText(), Toast.LENGTH_SHORT).show();
}
});
search_box.setVisibility(View.VISIBLE);
searched_list = new ArrayList<String>();
search_box.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
int length = search_box.getText().length();
searched_list.clear();
for (int i = 0; i < SearchQueries.length; i++) {
if (length <= SearchQueries.length) {
if (search_box.getText().toString().equalsIgnoreCase((String)SearchQueries[i]
.subSequence(0, length))) {
searched_list.add(SearchQueries[i].toString());
}
}
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
getApplicationContext(),
R.layout.listviews_search, searched_list);
customList.setAdapter(adapter);
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
}
公共类SearchActivity扩展了ListActivity{
编辑文本搜索框;
列表视图自定义列表;
private ArrayList results=new ArrayList();
私有字符串tableName=DatabaseHandler.TABLE\u搜索;
私有sqlitedatabasenewdb;
ArrayList搜索列表;
字符串[]搜索查询;
@抑制警告(“未选中”)
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.page\u搜索);
DatabaseHandler dbHelper=新的DatabaseHandler(this.getApplicationContext());
newDB=dbHelper.getWritableDatabase();
游标c=newDB.rawQuery(“从中选择SKEY”+
tableName,null);
如果(c!=null){
if(c.moveToFirst()){
做{
字符串skeys=c.getString(c.getColumnIndex(“skeys”);
结果:添加(skeys);
}而(c.moveToNext());
}
}
SearchQueries=(字符串[])results.toArray();
Collections.shuffle(Arrays.asList(results));
ArrayAdapter适配器=新的ArrayAdapter(
getApplicationContext(),R.layout.listviews\u搜索,搜索查询);
setAdapter(适配器);
setOnItemClickListener(新的OnItemClickListener(){
@凌驾
public void onItemClick(AdapterView父对象、视图、整型位置、长id){
Toast.makeText(getApplicationContext(),((TextView)视图).getText(),Toast.LENGTH_SHORT.show();
}
});
搜索框.设置可见性(视图.可见);
搜索的列表=新的ArrayList();
search_box.addTextChangedListener(新的TextWatcher(){
@凌驾
public void onTextChanged(字符序列、int start、int before、int count){
int length=search_box.getText().length();
已搜索的_list.clear();
for(int i=0;i if(length将ArrayList[]转换为字符串数组非常简单
String[] searchedQueries = new String[stock_list.size()];
stockArr = stock_list.toArray(stockArr);
for(String s : stockArr)
System.out.println(s);
为什么不使用SimpleCorsorAdapter而不是ArrayAdapter呢?然后可以在SQL中使用WHERE子句来搜索列表。这是一种非常常用的技术。一行
String[]searchedQueries=stock\u list.toArray(新字符串[stock\u list.size()]);
String[] searchedQueries = new String[stock_list.size()];
stockArr = stock_list.toArray(stockArr);
for(String s : stockArr)
System.out.println(s);