在eclipse中的Master Detail流程上运行一个新项目后，它会显示虚拟项目。
我想用SQLite的数据替换这些虚拟物品。
在调用DBAdapter的方法之后（在光标的帮助下）我能够在日志中打印这些值。
我不知道如何将ArrayList<GetterSetter>中存储的数据显示给主详细信息流。
请告诉我应该修改哪些课程，或者我应该如何编码？
更新
DBAdapter.java
public class DBAdapter extends SQLiteOpenHelper
{
static String name = "superstition.sqlite";
static String path = "";
public static ArrayList<GS> a;
static SQLiteDatabase sdb;
@Override
public void onCreate(SQLiteDatabase db)
{
// TODO Auto-generated method stub
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
// TODO Auto-generated method stub
}
private DBAdapter(Context v)
{
super(v, name, null, 1);
path = "/data/data/" + v.getApplicationContext().getPackageName() + "/databases";
}
public boolean checkDatabase()
{
SQLiteDatabase db = null;
try
{
db = SQLiteDatabase.openDatabase(path + "/" + name, null, SQLiteDatabase.OPEN_READONLY);
} catch (Exception e)
{
e.printStackTrace();
}
if (db == null)
{
return false;
}
else
{
db.close();
return true;
}
}
public static synchronized DBAdapter getDBAdapter(Context v)
{
return (new DBAdapter(v));
}
public void createDatabase(Context v)
{
this.getReadableDatabase();
try
{
InputStream myInput = v.getAssets().open(name);
// Path to the just created empty db
String outFileName = path +"/"+ name;
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0)
{
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
} catch (IOException e)
{
System.out.println(e);
}
}
public void openDatabase()
{
try
{
sdb = SQLiteDatabase.openDatabase(path + "/" + name, null,
SQLiteDatabase.OPEN_READWRITE);
} catch (Exception e)
{
System.out.println(e);
}
}
public ArrayList<GS> getData()
{
Cursor c1 = sdb.rawQuery("SELECT * FROM data", null);
a = new ArrayList<GS>();
while (c1.moveToNext())
{
GS gs = new GS();
gs.setItem(c1.getString(1));
gs.setDesc(c1.getString(2));
Log.v("id",gs.item+"");
a.add(gs);
}
return a;
}
}
GS.java // getter setter class
public class GS {
String item,desc;
public String getItem() {
return item;
}
public void setItem(String item) {
this.item = item;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
}
ItemListActivity.java
public class ItemListActivity extends FragmentActivity implements
ItemListFragment.Callbacks {
/**
* Whether or not the activity is in two-pane mode, i.e. running on a tablet
* device.
*/
public DummyContent dc;
private boolean mTwoPane;
public ArrayList<GS> q = new ArrayList<GS>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_item_list);
if (findViewById(R.id.item_detail_container) != null) {
// The detail container view will be present only in the
// large-screen layouts (res/values-large and
// res/values-sw600dp). If this view is present, then the
// activity should be in two-pane mode.
mTwoPane = true;
// In two-pane mode, list items should be given the
// 'activated' state when touched.
((ItemListFragment) getSupportFragmentManager().findFragmentById(
R.id.item_list)).setActivateOnItemClick(true);
}
DBAdapter db = DBAdapter.getDBAdapter(getApplicationContext());
if (!db.checkDatabase())
{
db.createDatabase(getApplicationContext());
}
db.openDatabase();
q=db.getData();
dc = new DummyContent();
// TODO: If exposing deep links into your app, handle intents here.
}
/**
* Callback method from {@link ItemListFragment.Callbacks} indicating that
* the item with the given ID was selected.
*/
@Override
public void onItemSelected(String id) {
if (mTwoPane) {
// In two-pane mode, show the detail view in this activity by
// adding or replacing the detail fragment using a
// fragment transaction.
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment).commit();
} else {
// In single-pane mode, simply start the detail activity
// for the selected item ID.
Intent detailIntent = new Intent(this, ItemDetailActivity.class);
detailIntent.putExtra(ItemDetailFragment.ARG_ITEM_ID, id);
startActivity(detailIntent);
}
}
}
DummyContent.java //我认为必须修改此静态块
public class DummyContent {
static int i=0;
/**
* An array of sample (dummy) items.
*/
public static List<DummyItem> ITEMS = new ArrayList<DummyItem>();
/**
* A map of sample (dummy) items, by ID.
*/
public static Map<String, DummyItem> ITEM_MAP = new HashMap<String, DummyItem>();
static {
for(i=0;i<182;i++)
addItem(new DummyItem(""+i, "Item "+i));
}
private static void addItem(DummyItem item) {
ITEMS.add(item);
ITEM_MAP.put(item.id, item);
}
/**
* A dummy item representing a piece of content.
*/
public static class DummyItem {
public String id;
public String content;
public DummyItem(String id, String content) {
this.id = id;
this.content = content;
}
@Override
public String toString() {
return content;
}
}
}
ItemDetailActivity.java //与eclipse生成的相同
public class ItemDetailActivity extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_item_detail);
// Show the Up button in the action bar.
getActionBar().setDisplayHomeAsUpEnabled(true);
// savedInstanceState is non-null when there is fragment state
// saved from previous configurations of this activity
// (e.g. when rotating the screen from portrait to landscape).
// In this case, the fragment will automatically be re-added
// to its container so we don't need to manually add it.
// For more information, see the Fragments API guide at:
//
// http://developer.android.com/guide/components/fragments.html
//
if (savedInstanceState == null) {
// Create the detail fragment and add it to the activity
// using a fragment transaction.
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, getIntent()
.getStringExtra(ItemDetailFragment.ARG_ITEM_ID));
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
getSupportFragmentManager().beginTransaction()
.add(R.id.item_detail_container, fragment).commit();
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
// This ID represents the Home or Up button. In the case of this
// activity, the Up button is shown. Use NavUtils to allow users
// to navigate up one level in the application structure. For
// more details, see the Navigation pattern on Android Design:
//
// http://developer.android.com/design/patterns/navigation.html#up-vs-back
//
NavUtils.navigateUpTo(this,
new Intent(this, ItemListActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
ItemDetailFragment.java //与eclipse生成的相同
public class ItemDetailFragment extends Fragment {
/**
* The fragment argument representing the item ID that this fragment
* represents.
*/
public static final String ARG_ITEM_ID = "item_id";
/**
* The dummy content this fragment is presenting.
*/
private DummyContent.DummyItem mItem;
/**
* Mandatory empty constructor for the fragment manager to instantiate the
* fragment (e.g. upon screen orientation changes).
*/
public ItemDetailFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments().containsKey(ARG_ITEM_ID)) {
// Load the dummy content specified by the fragment
// arguments. In a real-world scenario, use a Loader
// to load content from a content provider.
mItem = DummyContent.ITEM_MAP.get(getArguments().getString(
ARG_ITEM_ID));
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_item_detail,
container, false);
// Show the dummy content as text in a TextView.
if (mItem != null) {
((TextView) rootView.findViewById(R.id.item_detail))
.setText(mItem.content);
}
return rootView;
}
}
ItemListFragment.java //与eclipse生成的相同
public class ItemListFragment extends ListFragment {
/**
* The serialization (saved instance state) Bundle key representing the
* activated item position. Only used on tablets.
*/
private static final String STATE_ACTIVATED_POSITION = "activated_position";
/**
* The fragment's current callback object, which is notified of list item
* clicks.
*/
private Callbacks mCallbacks = sDummyCallbacks;
/**
* The current activated item position. Only used on tablets.
*/
private int mActivatedPosition = ListView.INVALID_POSITION;
/**
* A callback interface that all activities containing this fragment must
* implement. This mechanism allows activities to be notified of item
* selections.
*/
public interface Callbacks {
/**
* Callback for when an item has been selected.
*/
public void onItemSelected(String id);
}
/**
* A dummy implementation of the {@link Callbacks} interface that does
* nothing. Used only when this fragment is not attached to an activity.
*/
private static Callbacks sDummyCallbacks = new Callbacks() {
@Override
public void onItemSelected(String id) {
}
};
/**
* Mandatory empty constructor for the fragment manager to instantiate the
* fragment (e.g. upon screen orientation changes).
*/
public ItemListFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// TODO: replace with a real list adapter.
setListAdapter(new ArrayAdapter<DummyContent.DummyItem>(getActivity(),
android.R.layout.simple_list_item_activated_1,
android.R.id.text1, DummyContent.ITEMS));
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
// Restore the previously serialized activated item position.
if (savedInstanceState != null
&& savedInstanceState.containsKey(STATE_ACTIVATED_POSITION)) {
setActivatedPosition(savedInstanceState
.getInt(STATE_ACTIVATED_POSITION));
}
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// Activities containing this fragment must implement its callbacks.
if (!(activity instanceof Callbacks)) {
throw new IllegalStateException(
"Activity must implement fragment's callbacks.");
}
mCallbacks = (Callbacks) activity;
}
@Override
public void onDetach() {
super.onDetach();
// Reset the active callbacks interface to the dummy implementation.
mCallbacks = sDummyCallbacks;
}
@Override
public void onListItemClick(ListView listView, View view, int position,
long id) {
super.onListItemClick(listView, view, position, id);
// Notify the active callbacks interface (the activity, if the
// fragment is attached to one) that an item has been selected.
mCallbacks.onItemSelected(DummyContent.ITEMS.get(position).id);
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
if (mActivatedPosition != ListView.INVALID_POSITION) {
// Serialize and persist the activated item position.
outState.putInt(STATE_ACTIVATED_POSITION, mActivatedPosition);
}
}
/**
* Turns on activate-on-click mode. When this mode is on, list items will be
* given the 'activated' state when touched.
*/
public void setActivateOnItemClick(boolean activateOnItemClick) {
// When setting CHOICE_MODE_SINGLE, ListView will automatically
// give items the 'activated' state when touched.
getListView().setChoiceMode(
activateOnItemClick ? ListView.CHOICE_MODE_SINGLE
: ListView.CHOICE_MODE_NONE);
}
private void setActivatedPosition(int position) {
if (position == ListView.INVALID_POSITION) {
getListView().setItemChecked(mActivatedPosition, false);
} else {
getListView().setItemChecked(position, true);
}
mActivatedPosition = position;
}
}
答案 0 :(得分：4)
您只读取一次数据，但需要上下文才能这样做。扩展Application似乎是一个不错的选择：
public class ItemListApplication extends Application {
@Override
public void onCreate() {
super.onCreate();
String path = "/data/data/" + getPackageName() + "/databases";
if (!checkDatabase(path)) {
File file = new File(path);
file.mkdirs();
try {
InputStream myInput = getAssets().open(name);
// Path to the just created empty db
String outFileName = path + "/" + name;
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
} catch (IOException e) {
System.out.println(e);
}
}
SQLiteDatabase sdb = openDatabase(path);
getData(sdb);
sdb.close();
}
private ArrayList<GS> a;
public GS getItem(int id) {
return a.get(id);
}
public ArrayAdapter<GS> getAdapter(Context context) {
return new ArrayAdapter<GS>(context, android.R.layout.simple_list_item_activated_1,
android.R.id.text1, a);
}
private final String name = "superstition.sqlite";
private boolean checkDatabase(String path) {
SQLiteDatabase db = null;
try {
db = SQLiteDatabase.openDatabase(path + "/" + name, null,
SQLiteDatabase.OPEN_READONLY);
} catch (Exception e) {
e.printStackTrace();
}
if (db == null) {
return false;
} else {
db.close();
return true;
}
}
private SQLiteDatabase openDatabase(String path) {
return SQLiteDatabase.openDatabase(path + "/" + name, null,
SQLiteDatabase.OPEN_READWRITE);
}
private void getData(SQLiteDatabase sdb) {
Cursor c1 = sdb.rawQuery("SELECT * FROM data", null);
a = new ArrayList<GS>();
while (c1.moveToNext()) {
GS gs = new GS();
gs.setItem(c1.getString(1));
gs.setDesc(c1.getString(2));
Log.v("id", gs.item + "");
a.add(gs);
}
c1.close();
}
}
并将类名作为属性添加到<application>标记：
android:name="com.example.myproject.ItemListApplication"
这样可以在需要数据之前调用ItemListApplication.onCreate()一次。此外，在应用程序启动时创建的实例可通过getApplication()获得。
由于列表中的数据与适配器中的数据相同，因此int可用于按位置识别项目。
必须对您的代码进行一些更改：
<强> ItemListActivity.java
dc，q onCreate() 将onItemSelected()更改为以下内容：
@Override
public void onItemSelected(int id) {
if (mTwoPane) {
// In two-pane mode, show the detail view in this activity by
// adding or replacing the detail fragment using a
// fragment transaction.
Bundle arguments = new Bundle();
arguments.putInt(ItemDetailFragment.ARG_ITEM_ID, id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment).commit();
} else {
// In single-pane mode, simply start the detail activity
// for the selected item ID.
Intent detailIntent = new Intent(this, ItemDetailActivity.class);
detailIntent.putExtra(ItemDetailFragment.ARG_ITEM_ID, id);
startActivity(detailIntent);
}
}
<强> ItemDetailActivity.java
onCreate()中的更改了arguments的填充方式：
arguments.putInt(ItemDetailFragment.ARG_ITEM_ID, getIntent()
.getIntExtra(ItemDetailFragment.ARG_ITEM_ID, -1));
<强> ItemDetailFragment.java
mItem的类型更改为GS onCreate()中的将mItem的分配更改为：
mItem = ((ItemListApplication)getActivity().getApplication()).getItem(getArguments().getInt(
ARG_ITEM_ID));
onCreateView()中将文字设置为mItem.desc而不是mItem.content <强> ItemListFragment.java
Callbacks界面以及它的anomymus实现中将onItemSelected(String)的签名更改为onItemSelected(int) 将onCreate()更改为以下内容：
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
FragmentActivity activity = getActivity();
setListAdapter(((ItemListApplication)activity.getApplication()).getAdapter(activity));
}
mCallbacks.onItemSelected(DummyContent.ITEMS.get(position).id);更改为mCallbacks.onItemSelected(position);中的onListItemClick() <强> GS.java
覆盖toString()：
@Override
public String toString() {
return item;
}