从表中的数据featching麻烦 [英] trouble in featching data from tables
本文介绍了从表中的数据featching麻烦的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
当用户添加专辑它显示了的ListView
。假设你选择lovesong专辑用户写
歌曲名称和标题并保存到歌曲表(songid,ALBUMID,SONGNAME,SONGTITLE)。
用于获取歌曲表首歌我用
公开的ArrayList<&ALLDATA GT; getMyData(长ID)
{
ArrayList的<&ALLDATA GT; ArrayList的=新的ArrayList<&ALLDATA GT;();
光标C = db.query(DATABASE_TABLE_SONG,新的String [] {KEY_SONG_ID,KEY_ALBUM_ID,KEY_SONG_NAME,KEY_SONG_TITEL},KEY_ALBUM_ID +=+ ID,NULL,NULL,NULL,NULL);
ALLDATA myDatas; 而(c.moveToNext())
{
myDatas =新ALLDATA();
myDatas.song_id = c.getLong(c.getColumnIndex(KEY_SONG_ID));
myDatas.album_id = c.getInt(c.getColumnIndex(KEY_ALBUM_ID));
myDatas.song_name = c.getString(c.getColumnIndex(KEY_SONG_NAME))修剪()。
myDatas.song_title = c.getString(c.getColumnIndex(KEY_SONG_TITEL))修剪()。 arrayList.add(myDatas);
}
c.close();
返回数组列表;
}公共无效的onClick(视图v)
{
ALLDATA数据=新ALLDATA();
AlbumDAO albumDAO =新AlbumDAO(SongActivity.this);
albumDAO.open();
ArrayList的<&ALLDATA GT; MYDATA = albumDAO.getMyData(ALBUMID);
数据= mydata.get(ALBUMID);
Log.v(data.getAlbum_id(),data.getAlbum_id()+); albumDAO.close();
}
});
/////////////////// logcat的//////////////////////
18 02-06:07:37.948:ERROR / AndroidRuntime(27144):未捕获的处理程序:螺纹主力退出,由于未捕获的异常
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):java.lang.IndexOutOfBoundsException:无效的位置1,大小为0
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在java.util.ArrayList.get(ArrayList.java:341)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在krishna.ActionClass.SongActivity $ 2.onClick(SongActivity.java:79)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.View.performClick(View.java:2364)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.View.onTouchEvent(View.java:4179)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.widget.TextView.onTouchEvent(TextView.java:6541)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.View.dispatchTouchEvent(View.java:3709)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.app.Activity.dispatchTouchEvent(Activity.java:2061)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在com.android.internal.policy.impl.PhoneWindow $ DecorView.dispatchTouchEvent(PhoneWindow.java:1643)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.view.ViewRoot.handleMessage(ViewRoot.java:1691)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.os.Handler.dispatchMessage(Handler.java:99)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.os.Looper.loop(Looper.java:123)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在android.app.ActivityThread.main(ActivityThread.java:4363)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在java.lang.reflect.Method.invokeNative(本机方法)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在java.lang.reflect.Method.invoke(Method.java:521)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:860)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
02-06 18:07:38.069:ERROR / AndroidRuntime(27144):在dalvik.system.NativeStart.main(本机方法)
解决方案
您的数据库似乎返回0行,试试你的包裹while循环中,如果(c.moveToFirst()),因此
如果(c.moveToFirst())
{
而(c.moveToNext())
{
myDatas =新ALLDATA();
myDatas.song_id = c.getLong(c.getColumnIndex(KEY_SONG_ID));
myDatas.album_id = c.getInt(c.getColumnIndex(KEY_ALBUM_ID));
myDatas.song_name = c.getString(c.getColumnIndex(KEY_SONG_NAME))修剪()。
myDatas.song_title = c.getString(c.getColumnIndex(KEY_SONG_TITEL))修剪()。
arrayList.add(myDatas);
}
}
When user add album it show in ListView
. suppose you select lovesong album that user write
song name and title and save to song table(songid,albumid,songname,songtitle).
for getting song from song table i use
public ArrayList<Alldata> getMyData(long id)
{
ArrayList<Alldata> arrayList=new ArrayList<Alldata>();
Cursor c=db.query(DATABASE_TABLE_SONG, new String[]{KEY_SONG_ID,KEY_ALBUM_ID,KEY_SONG_NAME,KEY_SONG_TITEL}, KEY_ALBUM_ID+"="+id, null,null,null,null);
Alldata myDatas;
while(c.moveToNext())
{
myDatas=new Alldata();
myDatas.song_id=c.getLong(c.getColumnIndex(KEY_SONG_ID));
myDatas.album_id=c.getInt(c.getColumnIndex(KEY_ALBUM_ID));
myDatas.song_name=c.getString(c.getColumnIndex(KEY_SONG_NAME)).trim();
myDatas.song_title=c.getString(c.getColumnIndex(KEY_SONG_TITEL)).trim();
arrayList.add(myDatas);
}
c.close();
return arrayList;
}
public void onClick(View v)
{
Alldata data=new Alldata();
AlbumDAO albumDAO=new AlbumDAO(SongActivity.this);
albumDAO.open();
ArrayList<Alldata> mydata=albumDAO.getMyData(albumid);
data=mydata.get(albumid);
Log.v("data.getAlbum_id()",data.getAlbum_id()+"");
albumDAO.close();
}
});
/////////////////// LOGCAT //////////////////////
02-06 18:07:37.948: ERROR/AndroidRuntime(27144): Uncaught handler: thread main exiting due to uncaught exception
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): java.lang.IndexOutOfBoundsException: Invalid location 1, size is 0
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at java.util.ArrayList.get(ArrayList.java:341)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at krishna.ActionClass.SongActivity$2.onClick(SongActivity.java:79)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.View.performClick(View.java:2364)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.View.onTouchEvent(View.java:4179)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.widget.TextView.onTouchEvent(TextView.java:6541)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.View.dispatchTouchEvent(View.java:3709)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.app.Activity.dispatchTouchEvent(Activity.java:2061)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.view.ViewRoot.handleMessage(ViewRoot.java:1691)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.os.Handler.dispatchMessage(Handler.java:99)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.os.Looper.loop(Looper.java:123)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at android.app.ActivityThread.main(ActivityThread.java:4363)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at java.lang.reflect.Method.invokeNative(Native Method)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at java.lang.reflect.Method.invoke(Method.java:521)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
02-06 18:07:38.069: ERROR/AndroidRuntime(27144): at dalvik.system.NativeStart.main(Native Method)
解决方案
Your database seems to be returning 0 rows, try wrapping your while loop in if(c.moveToFirst()) so
if(c.moveToFirst())
{
while(c.moveToNext())
{
myDatas=new Alldata();
myDatas.song_id=c.getLong(c.getColumnIndex(KEY_SONG_ID));
myDatas.album_id=c.getInt(c.getColumnIndex(KEY_ALBUM_ID));
myDatas.song_name=c.getString(c.getColumnIndex(KEY_SONG_NAME)).trim();
myDatas.song_title=c.getString(c.getColumnIndex(KEY_SONG_TITEL)).trim();
arrayList.add(myDatas);
}
}
这篇关于从表中的数据featching麻烦的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
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