Change ExpandableList2 example to use async queries.

Change-Id: Ib3f79227808dcbcf6ec8f5f71c53b38932571ed4
This commit is contained in:
Jason Parks
2010-07-01 14:51:30 -05:00
parent 7f5176b8b2
commit 872ed49154

View File

@@ -17,59 +17,68 @@
package com.example.android.apis.view;
import android.app.ExpandableListActivity;
import android.content.AsyncQueryHandler;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.Contacts.People;
import android.widget.ExpandableListAdapter;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.provider.ContactsContract.Contacts;
import android.widget.CursorTreeAdapter;
import android.widget.SimpleCursorTreeAdapter;
/**
* Demonstrates expandable lists backed by Cursors
*/
public class ExpandableList2 extends ExpandableListActivity {
private int mGroupIdColumnIndex;
private String mPhoneNumberProjection[] = new String[] {
People.Phones._ID, People.Phones.NUMBER
private static final String[] CONTACTS_PROJECTION = new String[] {
Contacts._ID,
Contacts.DISPLAY_NAME
};
private static final int GROUP_ID_COLUMN_INDEX = 0;
private static final String[] PHONE_NUMBER_PROJECTION = new String[] {
Phone._ID,
Phone.NUMBER
};
private ExpandableListAdapter mAdapter;
private static final int TOKEN_GROUP = 0;
private static final int TOKEN_CHILD = 1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
private static final class QueryHandler extends AsyncQueryHandler {
private CursorTreeAdapter mAdapter;
// Query for people
Cursor groupCursor = managedQuery(People.CONTENT_URI,
new String[] {People._ID, People.NAME}, null, null, null);
public QueryHandler(Context context, CursorTreeAdapter adapter) {
super(context.getContentResolver());
this.mAdapter = adapter;
}
// Cache the ID column index
mGroupIdColumnIndex = groupCursor.getColumnIndexOrThrow(People._ID);
@Override
protected void onQueryComplete(int token, Object cookie, Cursor cursor) {
switch (token) {
case TOKEN_GROUP:
mAdapter.setGroupCursor(cursor);
break;
// Set up our adapter
mAdapter = new MyExpandableListAdapter(groupCursor,
this,
android.R.layout.simple_expandable_list_item_1,
android.R.layout.simple_expandable_list_item_1,
new String[] {People.NAME}, // Name for group layouts
new int[] {android.R.id.text1},
new String[] {People.NUMBER}, // Number for child layouts
new int[] {android.R.id.text1});
setListAdapter(mAdapter);
case TOKEN_CHILD:
int groupPosition = (Integer) cookie;
mAdapter.setChildrenCursor(groupPosition, cursor);
break;
}
}
}
public class MyExpandableListAdapter extends SimpleCursorTreeAdapter {
public MyExpandableListAdapter(Cursor cursor, Context context, int groupLayout,
// Note that the constructor does not take a Cursor. This is done to avoid querying the
// database on the main thread.
public MyExpandableListAdapter(Context context, int groupLayout,
int childLayout, String[] groupFrom, int[] groupTo, String[] childrenFrom,
int[] childrenTo) {
super(context, cursor, groupLayout, groupFrom, groupTo, childLayout, childrenFrom,
super(context, null, groupLayout, groupFrom, groupTo, childLayout, childrenFrom,
childrenTo);
}
@@ -78,15 +87,52 @@ public class ExpandableList2 extends ExpandableListActivity {
// Given the group, we return a cursor for all the children within that group
// Return a cursor that points to this contact's phone numbers
Uri.Builder builder = People.CONTENT_URI.buildUpon();
ContentUris.appendId(builder, groupCursor.getLong(mGroupIdColumnIndex));
builder.appendEncodedPath(People.Phones.CONTENT_DIRECTORY);
Uri.Builder builder = Contacts.CONTENT_URI.buildUpon();
ContentUris.appendId(builder, groupCursor.getLong(GROUP_ID_COLUMN_INDEX));
builder.appendEncodedPath(Contacts.Data.CONTENT_DIRECTORY);
Uri phoneNumbersUri = builder.build();
// The returned Cursor MUST be managed by us, so we use Activity's helper
// functionality to manage it for us.
return managedQuery(phoneNumbersUri, mPhoneNumberProjection, null, null, null);
}
mQueryHandler.startQuery(TOKEN_CHILD, groupCursor.getPosition(), phoneNumbersUri,
PHONE_NUMBER_PROJECTION, Phone.MIMETYPE + "=?",
new String[] { Phone.CONTENT_ITEM_TYPE }, null);
return null;
}
}
private QueryHandler mQueryHandler;
private CursorTreeAdapter mAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set up our adapter
mAdapter = new MyExpandableListAdapter(
this,
android.R.layout.simple_expandable_list_item_1,
android.R.layout.simple_expandable_list_item_1,
new String[] { Contacts.DISPLAY_NAME }, // Name for group layouts
new int[] { android.R.id.text1 },
new String[] { Phone.NUMBER }, // Number for child layouts
new int[] { android.R.id.text1 });
setListAdapter(mAdapter);
mQueryHandler = new QueryHandler(this, mAdapter);
// Query for people
mQueryHandler.startQuery(TOKEN_GROUP, null, Contacts.CONTENT_URI, CONTACTS_PROJECTION,
Contacts.HAS_PHONE_NUMBER + "=1", null, null);
}
@Override
protected void onDestroy() {
super.onDestroy();
// Null out the group cursor. This will cause the group cursor and all of the child cursors
// to be closed.
mAdapter.changeCursor(null);
mAdapter = null;
}
}