Android アプリのリスト ビューをメニューにキャストできません。これはクラス キャストの例外です。
コード：
package com.pocketbotanist;
import java.io.File;
import android.app.ListActivity;
import android.app.LoaderManager;
import android.content.CursorLoader;
import android.content.Intent;
import android.content.Loader;
import android.content.pm.ActivityInfo;
import android.content.res.Configuration;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView.AdapterContextMenuInfo;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.Spinner;
import com.pocketbotanist.contentprovider.MyEntryContentProvider;
import com.pocketbotanist.database.EntryTable;
public class HomeScreen extends ListActivity implements LoaderManager.LoaderCallbacks<Cursor> {
private static final int DELETE_ID = Menu.FIRST + 1;
// private Cursor cursor;
private SimpleCursorAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_screen);
this.getListView().setDividerHeight(2);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
//Initial folder creation code
File appDirectory = new File(Environment.getExternalStorageDirectory().toString()+"/Pocket Botanist/");
if (!appDirectory.exists()){
appDirectory.mkdir();
}
//Drop down list code
Spinner spinner = (Spinner) findViewById(R.id.action_spinner);
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.action_list, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);
fillData();
View listItem=(View)((Menu) this.getListView()).getItem(0);
registerForContextMenu(getListView());
if (adapter.isEmpty())
System.out.println("IT'S EMPTY");
String[] projection = { EntryTable.COLUMN_CUSTOMID };
long info = adapter.getItemId(0);
Uri uri = Uri.parse(MyEntryContentProvider.CONTENT_URI + "/"
+ info);
Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
cursor.moveToFirst();
System.out.println((cursor.getString(cursor
.getColumnIndexOrThrow(EntryTable.COLUMN_CUSTOMID))));
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
@Override
public boolean onContextItemSelected(MenuItem item) {
switch (item.getItemId()) {
case DELETE_ID:
String[] projection = { EntryTable.COLUMN_PHOTOS };
AdapterContextMenuInfo info = (AdapterContextMenuInfo) item
.getMenuInfo();
Uri uri = Uri.parse(MyEntryContentProvider.CONTENT_URI + "/"
+ info.id);
Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
cursor.moveToFirst();
File temp = new File(cursor.getString(cursor
.getColumnIndexOrThrow(EntryTable.COLUMN_PHOTOS)));
if(temp.exists()){
File[] files = temp.listFiles();
for(int i = 0; i < files.length; i++){
files[i].delete();
}
temp.delete();
}
getContentResolver().delete(uri, null, null);
fillData();
return true;
}
return super.onContextItemSelected(item);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_home_screen, menu);
//SearchView searchView = (SearchView) menu.findItem(R.id.menu_search).getActionView();
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.menu_settings:
settCall();
return true;
case R.id.menu_map:
map1_3();
return true;
case R.id.menu_edit:
entryScreen("New Entry");
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void entryScreen(String t){
Intent intent = new Intent(this, EntryScreen.class);
intent.putExtra("passer", t);
startActivity(intent);
}
public void settCall(){
Intent sett = new Intent(this,SettingsActivity.class);
startActivity(sett);
}
public void map1_3(){
Intent map13 = new Intent(this,Entrymap_1_3.class);
startActivity(map13);
}
// Opens the second activity if an entry is clicked
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
Intent i = new Intent(this, EntryScreen.class);
Uri itemUri = Uri.parse(MyEntryContentProvider.CONTENT_URI + "/" + id);
i.putExtra(MyEntryContentProvider.CONTENT_ITEM_TYPE, itemUri);
startActivity(i);
}
//When we create the loader we're going to get the projection for the ID, customID, species name, and time columns
//(insures that these exist within the database)
//then we create our cursor loader which will be responsible for loading data from the database
//using the projection and our content provider
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
String[] projection = { EntryTable.COLUMN_ID, EntryTable.COLUMN_CUSTOMID, EntryTable.COLUMN_SPECIES, EntryTable.COLUMN_TIME, EntryTable.COLUMN_PHOTOS, EntryTable.COLUMN_PHOTO };
CursorLoader cursorLoader = new CursorLoader(this,
MyEntryContentProvider.CONTENT_URI, projection, null, null, null);
return cursorLoader;
}
private void fillData() {
// Fields from the database (projection)
String[] from = new String[] { EntryTable.COLUMN_CUSTOMID, EntryTable.COLUMN_SPECIES , EntryTable.COLUMN_TIME, EntryTable.COLUMN_PHOTO};
// Fields on the UI to which we map
int[] to = new int[] { R.id.customidlabel, R.id.namelabel, R.id.timelabel, R.id.imageView };
getLoaderManager().initLoader(1, null, this); //changed to 1
adapter = new SimpleCursorAdapter(this, R.layout.list_row, null, from, to, 0);
setListAdapter(adapter);
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.add(0, DELETE_ID, 0, R.string.menu_delete);
}
@Override
public void onLoadFinished(Loader<Cursor> arg0, Cursor data) {
adapter.swapCursor(data);
}
@Override
public void onLoaderReset(Loader<Cursor> arg0) {
adapter.swapCursor(null);
}
}
ログキャット:
09-19 23:34:49.566: D/AbsListView(13532): Get MotionRecognitionManager
09-19 23:34:49.566: D/AbsListView(13532): onVisibilityChanged() is called, visibility : 8
09-19 23:34:49.566: D/AbsListView(13532): unregisterIRListener() is called
09-19 23:34:49.576: D/AndroidRuntime(13532): Shutting down VM
09-19 23:34:49.576: W/dalvikvm(13532): threadid=1: thread exiting with uncaught exception (group=0x417aeac8)
09-19 23:34:49.576: E/AndroidRuntime(13532): FATAL EXCEPTION: main
09-19 23:34:49.576: E/AndroidRuntime(13532): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.pocketbotanist/com.pocketbotanist.HomeScreen}: java.lang.ClassCastException: android.widget.ListView cannot be cast to android.view.Menu
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2247)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2297)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread.access$700(ActivityThread.java:152)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1282)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.os.Handler.dispatchMessage(Handler.java:99)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.os.Looper.loop(Looper.java:137)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread.main(ActivityThread.java:5328)
09-19 23:34:49.576: E/AndroidRuntime(13532): at java.lang.reflect.Method.invokeNative(Native Method)
09-19 23:34:49.576: E/AndroidRuntime(13532): at java.lang.reflect.Method.invoke(Method.java:511)
09-19 23:34:49.576: E/AndroidRuntime(13532): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
09-19 23:34:49.576: E/AndroidRuntime(13532): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
09-19 23:34:49.576: E/AndroidRuntime(13532): at dalvik.system.NativeStart.main(Native Method)
09-19 23:34:49.576: E/AndroidRuntime(13532): Caused by: java.lang.ClassCastException: android.widget.ListView cannot be cast to android.view.Menu
09-19 23:34:49.576: E/AndroidRuntime(13532): at com.pocketbotanist.HomeScreen.onCreate(HomeScreen.java:59)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.Activity.performCreate(Activity.java:5250)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1097)
09-19 23:34:49.576: E/AndroidRuntime(13532): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
09-19 23:34:49.576: E/AndroidRuntime(13532): ... 11 more
以前にカーソルとカーソルローダーに問題がありました。現在は修正されていると思いますが、このエラーのために現在発生しているとは言えません。このコードを改善するために誰かが提案しなければならないことは大歓迎です! どうもありがとうございました！