我根据developer.android.com /.
的教程制作了标签视图现在我已经从http://www.devx.com/wireless/Article/40842/0/page/1学习了数据库使用教程。
当我尝试结合使用DBAdapter和标签视图时，我最终会出现错误
Uncaught handler: thread main exiting due to uncaught exception.
我对android编程很新，所以任何建议都值得赞赏。我已经尝试过搜索多个线程了。
01-09 19:52:50.941: D/ddm-heap(228): Got feature list request
01-09 19:52:51.590: D/AndroidRuntime(228): Shutting down VM
01-09 19:52:51.590: W/dalvikvm(228): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
01-09 19:52:51.590: E/AndroidRuntime(228): Uncaught handler: thread main exiting due to uncaught exception
01-09 19:52:51.630: E/AndroidRuntime(228): java.lang.NullPointerException
01-09 19:52:51.630: E/AndroidRuntime(228): at android.widget.TabWidget.dispatchDraw(TabWidget.java:206)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.View.draw(View.java:6538)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.widget.FrameLayout.draw(FrameLayout.java:352)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1531)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.View.draw(View.java:6538)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.widget.FrameLayout.draw(FrameLayout.java:352)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1531)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.drawChild(ViewGroup.java:1529)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1258)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.View.draw(View.java:6538)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.widget.FrameLayout.draw(FrameLayout.java:352)
01-09 19:52:51.630: E/AndroidRuntime(228): at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1830)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewRoot.draw(ViewRoot.java:1349)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewRoot.performTraversals(ViewRoot.java:1114)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.view.ViewRoot.handleMessage(ViewRoot.java:1633)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.os.Handler.dispatchMessage(Handler.java:99)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.os.Looper.loop(Looper.java:123)
01-09 19:52:51.630: E/AndroidRuntime(228): at android.app.ActivityThread.main(ActivityThread.java:4363)
01-09 19:52:51.630: E/AndroidRuntime(228): at java.lang.reflect.Method.invokeNative(Native Method)
01-09 19:52:51.630: E/AndroidRuntime(228): at java.lang.reflect.Method.invoke(Method.java:521)
01-09 19:52:51.630: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
01-09 19:52:51.630: E/AndroidRuntime(228): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
01-09 19:52:51.630: E/AndroidRuntime(228): at dalvik.system.NativeStart.main(Native Method)
01-09 19:52:51.670: I/dalvikvm(228): threadid=7: reacting to signal 3
01-09 19:52:51.670: E/dalvikvm(228): Unable to open stack trace file '/data/anr/traces.txt': Permission denied
这是我的活动，包括三个标签。
import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.widget.TabHost;
public class Manager2012Activity extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Resources res = getResources(); // Resource object to get Drawables
TabHost tabHost = getTabHost(); // The activity TabHost
TabHost.TabSpec spec; // Resusable TabSpec for each tab
Intent intent; // Reusable Intent for each tab
// Create an Intent to launch an Activity for the tab (to be reused)
intent = new Intent().setClass(this, TeamActivity.class);
// Initialize a TabSpec for each tab and add it to the TabHost
spec = tabHost.newTabSpec("team").setIndicator("team",
res.getDrawable(R.drawable.ic_tab_team))
.setContent(intent);
tabHost.addTab(spec);
// Do the same for the other tabs
intent = new Intent().setClass(this, leagueActivity.class);
spec = tabHost.newTabSpec("league").setIndicator("league",
res.getDrawable(R.drawable.ic_tab_league))
.setContent(intent);
tabHost.addTab(spec);
intent = new Intent().setClass(this, ContinueActivity.class);
spec = tabHost.newTabSpec("continue").setIndicator("continue",
res.getDrawable(R.drawable.ic_tab_continue))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(2);
}
}
这是DBAdapter。
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter
{
public static final String KEY_ROWID = "_id";
public static final String KEY_DAY = "päivä";
public static final String KEY_MONTH = "kuukausi";
public static final String KEY_YEAR = "vuosi";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "manager";
private static final String DATABASE_TABLE = "game_date";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE =
"create table game_date (_id integer primary key autoincrement, "
+ "päivä text not null, kuukausi text not null, "
+ "vuosi text not null);";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS game_date");
onCreate(db);
}
}
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a title into the database---
public long insertTitle(String päivä, String kuukausi, String vuosi)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_DAY, päivä);
initialValues.put(KEY_MONTH, kuukausi);
initialValues.put(KEY_YEAR, vuosi);
return db.insert(DATABASE_TABLE, null, initialValues);
}
//---deletes a particular title---
public boolean deleteTitle(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID +
"=" + rowId, null) > 0;
}
//---retrieves all the titles---
public Cursor getAllTitles()
{
return db.query(DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_DAY,
KEY_MONTH,
KEY_YEAR},
null,
null,
null,
null,
null);
}
//---retrieves a particular title---
public Cursor getTitle(long rowId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_DAY,
KEY_MONTH,
KEY_YEAR
},
KEY_ROWID + "=" + rowId,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---updates a title---
public boolean updateTitle(long rowId, String päivä,
String kuukausi, String vuosi)
{
ContentValues args = new ContentValues();
args.put(KEY_DAY, päivä);
args.put(KEY_MONTH, kuukausi);
args.put(KEY_YEAR, vuosi);
return db.update(DATABASE_TABLE, args,
KEY_ROWID + "=" + rowId, null) > 0;
}
}
这是在数据库中插入数据并检索它的选项卡。
import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.widget.Toast;
public class ContinueActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DBAdapter db = new DBAdapter(this);
db.open();
long id;
id = db.insertTitle(
"1",
"1",
"2012");
id = db.insertTitle(
"15",
"2",
"2013");
db.close();
db.open();
Cursor c = db.getTitle(2);
if (c.moveToFirst())
DisplayTitle(c);
else
Toast.makeText(this, "No title found",
Toast.LENGTH_LONG).show();
db.close();
}
public void DisplayTitle(Cursor c)
{
Toast.makeText(this,
"id: " + c.getString(0) + "\n" +
"DAY: " + c.getString(1) + "\n" +
"MONTH: " + c.getString(2) + "\n" +
"YEAR: " + c.getString(3),
Toast.LENGTH_LONG).show();
}
}
答案 0 :(得分：0)
感谢您的提示thinksteep！
我设法通过编辑标签的布局xml文件来实现它。