Android 在游标数据中添加值
我正在开发一个应用程序,我需要把我的闹钟时间放在这样的列表视图中Android 在游标数据中添加值,android,database,listview,Android,Database,Listview,我正在开发一个应用程序,我需要把我的闹钟时间放在这样的列表视图中 12:45 13:11 我的问题是,我知道为什么会这样 我只有一个这样的科尔曼 45 十一, 我想从数据库中获取所有行,而不仅仅是一个列项,如何从数据库中获取所有行?有什么简单的解决办法吗 包装radiofm.arabel import android.content.ContentValues; import android.content.Context; import android.database.Cursor;
- 12:45
- 13:11
- 45
- 十一,
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String TAG = "DatabaseHelper";
private static final String TABLE_NAME = "people_table";
private static final String COL1 = "_id";
private static final String COL2 = "Hour";
private static final String COL3 = "Symbol";
private static final String COL4 = "Minutes";
public DatabaseHelper(Context context) {
super(context, TABLE_NAME, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
String createTable = "CREATE TABLE " + TABLE_NAME + " (" +
COL1 + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
COL2 + " TEXT, " +
COL3 + " TEXT, " +
COL4 + " TEXT " +
");";
db.execSQL(createTable);
}
@Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
db.execSQL("DROP IF TABLE EXISTS " + TABLE_NAME);
onCreate(db);
}
public boolean addData(String item1,String item2,String item3) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL2, item1);
contentValues.put(COL3, item2);
contentValues.put(COL4, item3);
Log.d(TAG, "addData: Adding " + item1 + " to " + TABLE_NAME);
long result = db.insert(TABLE_NAME, null, contentValues);
//if date as inserted incorrectly it will return -1
if (result == -1) {
return false;
} else {
return true;
}
}
public Cursor getListContents(){
SQLiteDatabase db = this.getWritableDatabase();
Cursor data = db.rawQuery("SELECT Hour, Symbol, Minutes FROM " + TABLE_NAME, null);
return data;
}
}
大宗报价
package radiofm.arabel;
导入android.content.Intent;
导入android.database.Cursor;
导入android.os.Bundle;
导入android.support.design.widget.FloatingActionButton;
导入android.support.design.widget.Snackbar;
导入android.support.v7.app.AppActivity;
导入android.support.v7.widget.Toolbar;
导入android.view.view;
导入android.widget.ArrayAdapter;
导入android.widget.Button;
导入android.widget.ListAdapter;
导入android.widget.ListView;
导入android.widget.Toast;
导入java.util.ArrayList;
公共类添加报警扩展了AppCompatActivity{
ListView listalarm;
数据库助手myDB;
按钮1;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity\u add\u alarm);
Toolbar Toolbar=(Toolbar)findViewById(R.id.Toolbar);
设置支持操作栏(工具栏);
listalarm=(ListView)findViewById(R.id.listalarm);
myDB=新数据库助手(此);
button1=(按钮)findViewById(R.id.addalarm);
button1.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图){
Intent Intent=新意图(view.getContext(),Alarm.class);
view.getContext().startActivity(Intent);}
});
//从数据库填充ArrayList,然后查看它
ArrayList theList=新的ArrayList();
游标数据=myDB.getListContents();
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
add(data.getString(2));
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
}
}
}
您可能错过了数据库中的Hour
列:
更改:
if(data.getCount() == 0){
Toast.makeText(this, "There are no contents in this list!",Toast.LENGTH_LONG).show();
}else{
while(data.moveToNext()){
theList.add(data.getString(2));
ListAdapter listAdapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,theList);
listalarm.setAdapter(listAdapter);
}
}
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
add(data.getString(2));
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
}
致:
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
添加(data.getString(0)+:“+data.getString(2));
}
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
您可能错过了数据库中的Hour
列:
更改:
if(data.getCount() == 0){
Toast.makeText(this, "There are no contents in this list!",Toast.LENGTH_LONG).show();
}else{
while(data.moveToNext()){
theList.add(data.getString(2));
ListAdapter listAdapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,theList);
listalarm.setAdapter(listAdapter);
}
}
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
add(data.getString(2));
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
}
致:
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
添加(data.getString(0)+:“+data.getString(2));
}
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
这里是从列索引2中获取数据并将其放入列表中。本栏显示的是会议记录如果你也想要小时,你必须从光标
中获取时间。记住,计算机只做你让它做的事情
或者,您可以使用光标或适配器。您很可能需要自己创建一个自定义适配器类,以便从游标获取值并正确显示它们
这里是从列索引2中获取数据并将其放入列表中。本栏显示的是会议记录如果你也想要小时,你必须从光标
中获取时间。记住,计算机只做你让它做的事情
或者,您可以使用光标或适配器。您很可能需要自己创建一个自定义适配器类,以便从游标中获取值并正确显示它们。尝试这样从游标中获取值并相应地使用
String col1_value=data.getString(data.getColumnIndex(COL1));
String col2_value=data.getString(data.getColumnIndex(COL2));
String col3_value=data.getString(data.getColumnIndex(COL3));
并在添加列表中的所有值后通知您的适配器,如下所示
Cursor data = myDB.getListContents();
if(data.getCount() == 0){
Toast.makeText(this, "There are no contents in this list!",Toast.LENGTH_LONG).show();
}else{
while(data.moveToNext()){
theList.add(data.getString(data.getColumnIndex(COL2)));
}
ListAdapter listAdapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,theList);
listalarm.setAdapter(listAdapter);
}
cursordata=myDB.getListContents();
if(data.getCount()==0){
Toast.makeText(这是“此列表中没有内容!”,Toast.LENGTH_LONG.show();
}否则{
while(data.moveToNext()){
add(data.getString(data.getColumnIndex(COL2));
}
ListAdapter ListAdapter=new ArrayAdapter(这是android.R.layout.simple\u list\u item\u 1,theList);
listalarm.setAdapter(listAdapter);
}
尝试这样从游标中提取,并相应地使用
String col1_value=data.getString(data.getColumnIndex(COL1));
String col2_value=data.getString(data.getColumnIndex(COL2));
String col3_value=data.getString(data.getColumnIndex(COL3));
并在添加列表中的所有值后通知您的适配器,如下所示
Cursor data = myDB.getListContents();
if(data.getCount() == 0){
Toast.makeText(this, "There are no contents in this list!",Toast.LENGTH_LONG).show();
}else{
while(data.moveToNext()){
theList.add(data.getString(data.getColumnIndex(COL2)));
}
ListAdapter listAdapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,theList);
listalarm.setAdapter(listAdapter);
}
Curso