我写了一些代码。它不会给出错误，但它根本不起作用。
当我尝试调试它时，它说：不幸的是，您的应用程序已停止。
请帮助我，我是开发新手
数据库助手类是
public class DatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION=1;
private static final String DATABASE_NAME= "permitManager",
TABLE_CONTACTS ="contacts",
KEY_ID = "id",
KEY_CAR="car",
KEY_STATUS="status",
KEY_IMAGEURI="imageUri";
public DatabaseHandler(Context context){
super(context, DATABASE_NAME,null,DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db){
db.execSQL("CREATE TABLE " + TABLE_CONTACTS +""+ KEY_ID + " INTEGER PRIMARY," + KEY_CAR + "TEXT," + KEY_STATUS + "TEXT," + KEY_IMAGEURI + "TEXT,");
}
@Override
public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){
db.execSQL("DROP TABLE IF EXISTS"+ TABLE_CONTACTS);
onCreate(db);
}
public void createContact(Contact contact){
SQLiteDatabase db = getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_CAR,contact.getCar());
values.put(KEY_STATUS,contact.getStatus());
values.put(KEY_IMAGEURI, contact.getimageURI().toString());
db.insert(TABLE_CONTACTS,null,values);
db.close();
}
public Contact getContact(int id){
SQLiteDatabase db =getReadableDatabase();
Cursor cursor =db.query(TABLE_CONTACTS, new String[]{KEY_ID,KEY_CAR,KEY_STATUS,KEY_IMAGEURI},KEY_ID + "=?" , new String[]{String.valueOf(id)},null,null,null);
if(cursor!=null)
cursor.moveToFirst();
Contact contact = new Contact(Integer.parseInt(cursor.getString(0)),cursor.getString(1),cursor.getString(2), Uri.parse(cursor.getString(3)));
db.close();
cursor.close();
return contact;
}
public void deleteContact(Contact contact){
SQLiteDatabase db = getWritableDatabase() ;
db.delete(TABLE_CONTACTS,KEY_ID+"=?",new String[]{String.valueOf(contact.getid())});
db.close();
}
public int getContactCount(){
SQLiteDatabase db= getReadableDatabase();
Cursor cursor =db.rawQuery("SELECT * FROM" + TABLE_CONTACTS,null);
int count = cursor.getCount();
db.close();
cursor.close();
return count;
}
public int updateContact(Contact contact){
SQLiteDatabase db= getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_CAR,contact.getCar());
values.put(KEY_STATUS,contact.getStatus());
values.put(KEY_IMAGEURI, contact.getimageURI().toString());
db.insert(TABLE_CONTACTS,null,values);
return db.update(TABLE_CONTACTS,values,KEY_ID +"=?",new String[]{String.valueOf(contact.getid())});
}
public List<Contact> getAllContacts(){
List<Contact> contacts = new ArrayList<>();
SQLiteDatabase db = getWritableDatabase();
Cursor cursor =db.rawQuery("SELECT * FROM"+ TABLE_CONTACTS,null);
if (cursor.moveToFirst()){
do {
Contact contact = new Contact(Integer.parseInt(cursor.getString(0)),cursor.getString(1),cursor.getString(2),Uri.parse(cursor.getString(3)));
contacts.add(contact);
}
while (cursor.moveToNext());
}
return contacts;
}
}
主要活动类是
public class MainActivity extends ActionBarActivity {
EditText carTxt, statusTxt;
ImageView contactImageImgView;
List<Contact> Contacts = new ArrayList<Contact>();
ListView contactListView;
Uri imageUri=null;
DatabaseHandler dbHandler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
carTxt = (EditText) findViewById(R.id.txtCar);
statusTxt = (EditText) findViewById(R.id.txtStatus);
contactListView = (ListView) findViewById(R.id.listView);
contactImageImgView = (ImageView) findViewById(R.id.imgViewContactImage);
dbHandler = new DatabaseHandler(getApplicationContext());
TabHost tabHost = (TabHost) findViewById(R.id.tabHost);
tabHost.setup();
TabHost.TabSpec tabSpec = tabHost.newTabSpec("Creator");
tabSpec.setContent(R.id.Creator);
tabSpec.setIndicator("Creator");
tabHost.addTab(tabSpec);
tabSpec = tabHost.newTabSpec("List");
tabSpec.setContent(R.id.List);
tabSpec.setIndicator("List");
tabHost.addTab(tabSpec);
final Button addBtn = (Button) findViewById(R.id.btnAdd);
addBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Contact contact = new Contact(dbHandler.getContactCount(),String.valueOf(carTxt.getText()),String.valueOf(statusTxt.getText()),imageUri);
dbHandler.createContact(contact);
Contacts.add(contact);
populateList();
Toast.makeText(getApplicationContext(), carTxt.getText().toString() + " has been add to list", Toast.LENGTH_SHORT).show();
}
});
carTxt.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
addBtn.setEnabled(!carTxt.getText().toString().trim().isEmpty());
}
@Override
public void afterTextChanged(Editable s) {
}
});
contactImageImgView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Contact Image"), 1);
}
});
List<Contact> addableContacts = dbHandler.getAllContacts();
int contactcount = dbHandler.getContactCount();
for(int i =0;i< contactcount;i++) {
Contacts.add(addableContacts.get(1));
}
if(!addableContacts.isEmpty())
populateList();
}
public void onActivityResult(int reqcode, int rescode, Intent data){
if(rescode == RESULT_OK){
if(reqcode == 1){
imageUri = data.getData();
contactImageImgView.setImageURI(data.getData());
}
}
}
private void populateList() {
ArrayAdapter<Contact> adapter = new ContactListAdapter();
contactListView.setAdapter(adapter);
}
private class ContactListAdapter extends ArrayAdapter<Contact> {
public ContactListAdapter() {
super(MainActivity.this, R.layout.listview_item, Contacts);
}
@Override
public View getView(int position, View view, ViewGroup parent) {
if (view == null)
view = getLayoutInflater().inflate(R.layout.listview_item, parent, false);
Contact currentContact = Contacts.get(position);
TextView car = (TextView) view.findViewById(R.id.contactname);
car.setText(currentContact.getCar());
TextView status = (TextView) view.findViewById(R.id.status);
status.setText(currentContact.getStatus());
ImageView img = (ImageView) view.findViewById(R.id.img);
img.setImageURI(currentContact.getimageURI());
return view;
}
}
}
logcat 是
08-27 05:17:06.704 13110-13110/com.newthinktank.helloworld E/Trace﹕ error opening trace file: No such file or directory (2)
08-27 05:17:06.759 13110-13110/com.newthinktank.helloworld I/System.out﹕ Sending WAIT chunk
08-27 05:17:06.759 13110-13110/com.newthinktank.helloworld W/ActivityThread﹕ Application com.newthinktank.helloworld is waiting for the debugger on port 8100...
08-27 05:17:06.766 13110-13117/com.newthinktank.helloworld I/dalvikvm﹕ Debugger is active
08-27 05:17:06.962 13110-13110/com.newthinktank.helloworld I/System.out﹕ Debugger has connected
08-27 05:17:06.962 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:07.157 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:07.360 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:07.563 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:07.759 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:07.962 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:08.165 13110-13110/com.newthinktank.helloworld I/System.out﹕ waiting for debugger to settle...
08-27 05:17:08.368 13110-13110/com.newthinktank.helloworld I/System.out﹕ debugger has settled (1343)
08-27 05:17:08.766 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to find class referenced in signature (Landroid/view/SearchEvent;)
08-27 05:17:08.766 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.view.Window$Callback.onSearchRequested, referenced from method android.support.v7.internal.view.WindowCallbackWrapper.onSearchRequested
08-27 05:17:08.774 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve interface method 14046: Landroid/view/Window$Callback;.onSearchRequested (Landroid/view/SearchEvent;)Z
08-27 05:17:08.774 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x72 at 0x0002
08-27 05:17:08.774 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.view.Window$Callback.onWindowStartingActionMode, referenced from method android.support.v7.internal.view.WindowCallbackWrapper.onWindowStartingActionMode
08-27 05:17:08.774 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve interface method 14050: Landroid/view/Window$Callback;.onWindowStartingActionMode (Landroid/view/ActionMode$Callback;I)Landroid/view/ActionMode;
08-27 05:17:08.774 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x72 at 0x0002
08-27 05:17:10.149 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.view.ViewGroup.onRtlPropertiesChanged, referenced from method android.support.v7.widget.Toolbar.onRtlPropertiesChanged
08-27 05:17:10.149 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve virtual method 13947: Landroid/view/ViewGroup;.onRtlPropertiesChanged (I)V
08-27 05:17:10.149 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x6f at 0x0007
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.internal.widget.TintTypedArray.getChangingConfigurations
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve virtual method 403: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.internal.widget.TintTypedArray.getType
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve virtual method 425: Landroid/content/res/TypedArray;.getType (I)I
08-27 05:17:10.173 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.content.res.Resources.getDrawable, referenced from method android.support.v7.internal.widget.ResourcesWrapper.getDrawable
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve virtual method 366: Landroid/content/res/Resources;.getDrawable (ILandroid/content/res/Resources$Theme;)Landroid/graphics/drawable/Drawable;
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld I/dalvikvm﹕ Could not find method android.content.res.Resources.getDrawableForDensity, referenced from method android.support.v7.internal.widget.ResourcesWrapper.getDrawableForDensity
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ VFY: unable to resolve virtual method 368: Landroid/content/res/Resources;.getDrawableForDensity (IILandroid/content/res/Resources$Theme;)Landroid/graphics/drawable/Drawable;
08-27 05:17:10.563 13110-13110/com.newthinktank.helloworld D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
08-27 05:17:11.485 13110-13110/com.newthinktank.helloworld E/SQLiteLog﹕ (1) near "FROMcontacts": syntax error
08-27 05:17:11.493 13110-13110/com.newthinktank.helloworld D/AndroidRuntime﹕ Shutting down VM
08-27 05:17:11.493 13110-13110/com.newthinktank.helloworld W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x40b762a0)
08-27 05:17:11.665 13110-13110/com.newthinktank.helloworld E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.newthinktank.helloworld/com.newthinktank.helloworld.MainActivi ty}: android.database.sqlite.SQLiteException: near "FROMcontacts": syntax error (code 1): , while compiling: SELECT * FROMcontacts
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2174)
at android.app.ActivityThread.access$700(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1267)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5059)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:792)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.database.sqlite.SQLiteException: near "FROMcontacts": syntax error (code 1): , while compiling: SELECT * FROMcontacts
at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnecti on.java:882)
at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:493)
at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at android.database.sqlite.SQLiteProgram.<init> (SQLiteProgram.java:58)
at android.database.sqlite.SQLiteQuery.<init> (SQLiteQuery.java:37)
at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44)
at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314)
at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1253)
at com.newthinktank.helloworld.DatabaseHandler.getAllContacts(DatabaseHandler.java:83)
at com.newthinktank.helloworld.MainActivity.onCreate(MainActivity.java:106)
at android.app.Activity.performCreate(Activity.java:5058)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2174)
at android.app.ActivityThread.access$700(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1267)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5059)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:792)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
at dalvik.system.NativeStart.main(Native Method)
08-27 05:17:12.266 13110-13110/com.newthinktank.helloworld I/Process﹕ Sending signal. PID: 13110 SIG: 9