我现在正在编写一个应用程序，需要在数据库中准备一些数据，我尝试了这个问题的方法
Ship an application with a database
事实证明你无法在android 2.3中复制数据库。
所以我设置了一个启动画面，并希望在那里运行一些数据初始化。
我尝试过Thread和Asyctask，但仍然遇到这个奇怪的问题，我的insert_data方法不断出现异常
它让我发疯，请帮忙
Splash.java
public class Splash extends Activity {
private ChannelDB mDB;
private TextView loading;
private String channelS_TABLE;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
new SetDB().execute();
}
private class SetDB extends AsyncTask<String, String, String> {
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
try {
Log.d("Splash","table check not running yet");
if (tabIsExist(channelS_TABLE) != true ){
Log.d("Splash","table check complete and not exist");
mDB.Reset();
Log.d("Splash","database reset");
some data insert
));
}else{
synchronized(this){
Log.i("Splash", "the table is there");
wait(3000);}
Intent i = new Intent();
i.setClassName("com.appkon.hdtvs",
"com.appkon.hdtvs.HDtvs");
finish();
startActivity(i);
}
}catch (Exception e) {
Log.i("Splash", "setDB exception");
Intent i = new Intent();
i.setClassName("com.appkon.hdtvs",
"com.appkon.hdtvs.HDtvs");
finish();
startActivity(i);
}
return null;
}
protected void onPreExecute(String load) {
}
protected void onPostExecute(String finish) {
Intent i = new Intent();
i.setClassName("com.appkon.hdtvs",
"com.appkon.hdtvs.HDtvs");
finish();
startActivity(i);
}
}
public boolean tabIsExist(String tableName){
boolean result = false;
if(tableName == null){
return false;
}
Cursor cursor= ChannelDB.check();
startManagingCursor(cursor);
try {
if(cursor.moveToNext()){
int count = cursor.getInt(0);
if(count>0){
result = true;
}
}
} catch (Exception e) {
Log.e(this.toString(),"error:"+e.toString());
Intent intent = new Intent(this,HDtvs.class);
startActivity(intent);
this.finish();
Log.d("Splash","tabIsExist Exception");
}
return result;
}
}
错误追踪
12-05 07:52:20.542: INFO/System.out(575): debugger has settled (1460)
12-05 07:52:21.442: DEBUG/dalvikvm(575): GC freed 679 objects / 53552 bytes in 135ms
12-05 07:52:21.932: DEBUG/Splash(575): table check not running yet
12-05 07:52:21.932: DEBUG/Splash(575): table check complete and not exist
12-05 07:52:21.932: INFO/Splash(575): setDB exception
12-05 07:52:21.982: INFO/ActivityManager(51): Starting activity: Intent { cmp=com.appkon.hdtvs/.HDtvs }
12-05 07:52:22.482: WARN/ActivityManager(51): Duplicate finish request for HistoryRecord{44d4aa10 com.appkon.hdtvs/.Splash}
12-05 07:52:22.502: INFO/ActivityManager(51): Starting activity: Intent { cmp=com.appkon.hdtvs/.HDtvs }
对于Bindal来说很棒的解决方案，但我仍有问题，我定义了一个方法来在我的数据库助手类中添加条目并使用它将数据插入数据库，但它似乎无法正常工作
这是我在databasehelper类中定义的方法
public void createchannelEntry(ChannelPoster channel) {
openDB();
ByteArrayOutputStream out = new ByteArrayOutputStream();
channel.getPoster().compress(Bitmap.CompressFormat.PNG, 100, out);
ContentValues cv = new ContentValues();
cv.put(KEY_POSTER, out.toByteArray());
cv.put(KEY_CHANNEL, channel.getChannel());
cv.put(KEY_PATH, channel.getPath());
cv.put(KEY_DBLINK, channel.getDBlink());
mDb.insert(channelS_TABLE, null, cv);
closeDB();
}
这是我插入数据的方式
Bitmap sherlock = BitmapFactory.decodeResource(getResources(), R.drawable.sherlock);
mDB.createchannelEntry(new ChannelPoster(aa, "aa" ,"ll" ,"ha" ));
我有一个用于保存条目的JavaBean
public class ChannelPoster {
private Bitmap poster;
private String channel;
private String path;
private String dblink;
public ChannelPoster(Bitmap pi, String c, String p, String d) {
poster = pi;
channel = c;
path = p;
dblink = d;
}
public Bitmap getPoster() { return poster; }
public String getChannel() { return channel; }
public String getPath() { return path; }
public String getDBlink() { return dblink; }
}
现在我在这里添加Logcat记录
这是我的代码
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
try {
createDataBase();
} catch (Exception e) {
Intent intent = new Intent(this,HDtvs.class);
startActivity(intent);
this.finish();
Log.d("Splash","createDataBaseException");
}
}
public void createDataBase() throws Exception
{
boolean dbExist = checkDataBase();
if (dbExist){
Intent intent = new Intent(this,HDtvs.class);
startActivity(intent);
this.finish();
Log.d("Splash","table exist");
}
else
{
try{
mDB.Reset();
Log.d("Splash","database reset");
Bitmap bigbang1 = BitmapFactory.decodeResource(getResources(), R.drawable.bigbang1);
mDB.createchannelEntry(new ChannelPoster(bigbang1, "生活大爆炸（第一季）" ,"http://appkon.com/hdtvs/channel/bigbang1.xml" ,"http://movie.douban.com/subject/5372374/" ));
}catch (Exception e){
Log.d("splash","data insert exception");
Intent intent = new Intent(this,HDtvs.class);
startActivity(intent);
this.finish();
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each
* time you open the application.
*
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase()
{
SQLiteDatabase checkDB = null;
try
{
String myPath = "data/data/com.appkon.hdtvs/databases/" + "channelDB";
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
}catch (Exception e){
Log.d("Splash","database does't exist yet.");
}
if (checkDB != null){
checkDB.close();
return true;
}
else
return false;
}
}
这是我的logcat记录
> 12-05 08:35:14.222: INFO/System.out(824): debugger has settled (1435)
> 12-05 08:35:15.032: DEBUG/dalvikvm(824): GC freed 621 objects / 51304
> bytes in 98ms 12-05 08:35:15.373: ERROR/Database(824):
> sqlite3_open_v2("data/data/com.appkon.hdtvs/databases/channelDB",
> &handle, 2, NULL) failed 12-05 08:35:15.382: DEBUG/Splash(824):
> database does't exist yet. 12-05 08:35:15.382: DEBUG/splash(824): data
> insert exception 12-05 08:35:15.402: INFO/ActivityManager(51):
> Starting activity: Intent { cmp=com.appkon.hdtvs/.HDtvs } 12-05
> 08:35:16.753: INFO/ActivityManager(51): Displayed activity
> com.appkon.hdtvs/.HDtvs: 1298 ms (total 6152 ms)
答案 0 :(得分：3)
public void createDataBase() throws Exception
{
boolean dbExist = checkDataBase();
if (dbExist){
System.out.println("Database Exist");
}
else
{
this.getReadableDatabase();
try{
}catch (Exception e){
throw new Error(e.getMessage());
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each
* time you open the application.
*
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase()
{
SQLiteDatabase checkDB = null;
try
{
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
}catch (Exception e){
System.out.println("database does't exist yet.");
}
if (checkDB != null){
checkDB.close();
System.out.println("My db is:- " + checkDB.isOpen());
return true;
}
else
return false;
}