/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package edu.gatech.oad.rocket.findmythings.list;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.RelativeLayout;
import android.widget.TextView;
import java.util.*;
/**
* A concrete BaseAdapter that is backed by a List of arbitrary objects.
*/
public abstract class ArrayListAdapter<T> extends BaseAdapter {
/**
* Contains the list of objects that represent the data of this ArrayAdapter.
* The content of this list is referred to as "the array" in the documentation.
*/
protected List<T> mObjects = new ArrayList<T>();
/**
* Lock used to modify the content of {@link #mObjects}. Any write operation
* performed on the array should be synchronized on this lock. This lock is also
* used by the filter to make a synchronized copy of
* the original array of data.
*/
protected final Object mLock = new Object();
/**
* The resource indicating what views to inflate to display the content of this
* array adapter.
*/
private int mResource;
/**
* The resource indicating what views to inflate to display the content of this
* array adapter in a drop down widget.
*/
private int mDropDownResource;
/**
* If the inflated resource is not a TextView, this field ID is used to find
* a TextView inside the inflated views hierarchy. This field must contain the
* identifier that matches the one defined in the resource file.
*/
private int mFieldId = 0;
/**
* Indicates whether or not {@link #notifyDataSetChanged()} must be called whenever
* {@link #mObjects} is modified.
*/
private boolean mNotifyOnChange = true;
private Context mContext;
// A copy of the original mObjects array, initialized from and then used instead as soon as
// the mFilter ArrayFilter is used. mObjects will then only contain the filtered values.
protected ArrayList<T> mOriginalValues;
private LayoutInflater mInflater;
/**
* Constructor
*
* @param context The current context.
* @param textViewResourceId The resource ID for a layout file containing a TextView to use when
* instantiating views.
*/
public ArrayListAdapter(Context context, int textViewResourceId) {
this(context, textViewResourceId, 0);
}
/**
* Constructor
*
* @param context The current context.
* @param resource The resource ID for a layout file containing a layout to use when
* instantiating views.
* @param textViewResourceId The id of the TextView within the layout resource to be populated
*/
public ArrayListAdapter(Context context, int resource, int textViewResourceId) {
mContext = context;
mInflater = LayoutInflater.from(context);
mResource = mDropDownResource = resource;
mFieldId = textViewResourceId;
}
/**
* Adds the specified object at the end of the array.
*
* @param object The object to add at the end of the array.
*/
public void add(T object) {
synchronized (mLock) {
if (mOriginalValues != null) {
mOriginalValues.add(object);
} else {
mObjects.add(object);
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* Adds the specified Collection at the end of the array.
*
* @param collection The Collection to add at the end of the array.
*/
public void addAll(Collection<? extends T> collection) {
synchronized (mLock) {
if (mOriginalValues != null) {
mOriginalValues.addAll(collection);
} else {
mObjects.addAll(collection);
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* Inserts the specified object at the specified index in the array.
*
* @param object The object to insert into the array.
* @param index The index at which the object must be inserted.
*/
public void insert(T object, int index) {
synchronized (mLock) {
if (mOriginalValues != null) {
mOriginalValues.add(index, object);
} else {
mObjects.add(index, object);
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* Removes the specified object from the array.
*
* @param object The object to remove.
*/
public void remove(T object) {
synchronized (mLock) {
if (mOriginalValues != null) {
mOriginalValues.remove(object);
} else {
mObjects.remove(object);
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* Remove all elements from the list.
*/
public void clear() {
synchronized (mLock) {
if (mOriginalValues != null) {
mOriginalValues.clear();
} else {
mObjects.clear();
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* Sorts the content of this adapter using the specified comparator.
*
* @param comparator The comparator used to sort the objects contained
* in this adapter.
*/
public void sort(Comparator<? super T> comparator) {
synchronized (mLock) {
if (mOriginalValues != null) {
Collections.sort(mOriginalValues, comparator);
} else {
Collections.sort(mObjects, comparator);
}
}
if (mNotifyOnChange) notifyDataSetChanged();
}
/**
* {@inheritDoc}
*/
@Override
public void notifyDataSetChanged() {
super.notifyDataSetChanged();
mNotifyOnChange = true;
}
/**
* Control whether methods that change the list ({@link #add},
* {@link #insert}, {@link #remove}, {@link #clear}) automatically call
* {@link #notifyDataSetChanged}. If set to false, caller must
* manually call notifyDataSetChanged() to have the changes
* reflected in the attached view.
*
* The default is true, and calling notifyDataSetChanged()
* resets the flag to true.
*
* @param notifyOnChange if true, modifications to the list will
* automatically call {@link
* #notifyDataSetChanged}
*/
public void setNotifyOnChange(boolean notifyOnChange) {
mNotifyOnChange = notifyOnChange;
}
/**
* Returns the context associated with this array adapter. The context is used
* to create views from the resource passed to the constructor.
*
* @return The Context associated with this adapter.
*/
public Context getContext() {
return mContext;
}
/**
* {@inheritDoc}
*/
public int getCount() {
return mObjects.size();
}
/**
* {@inheritDoc}
*/
public T getItem(int position) {
return mObjects.get(position);
}
/**
* Returns the position of the specified item in the array.
*
* @param item The item to retrieve the position of.
*
* @return The position of the specified item.
*/
public int getPosition(T item) {
return mObjects.indexOf(item);
}
/**
* {@inheritDoc}
*/
public long getItemId(int position) {
return position;
}
/**
* {@inheritDoc}
*/
public View getView(int position, View convertView, ViewGroup parent) {
return createViewFromResource(position, convertView, parent, mResource);
}
private View createViewFromResource(int position, View convertView, ViewGroup parent,
int resource) {
View view;
TextView text;
if (convertView == null) {
view = mInflater.inflate(resource, parent, false);
} else {
view = convertView;
}
try {
if (mFieldId == 0) {
// If no custom field is assigned, assume the whole resource is a TextView
text = (TextView) view;
} else {
// Otherwise, find the TextView field within the layout
text = (TextView) view.findViewById(mFieldId);
}
} catch (ClassCastException e) {
Log.e("ArrayAdapter", "You must supply a resource ID for a TextView");
throw new IllegalStateException(
"ArrayAdapter requires the resource ID to be a TextView", e);
}
T item = getItem(position);
if (item instanceof CharSequence) {
text.setText((CharSequence)item);
} else {
text.setText(item.toString());
}
return view;
}
/**
* <p>Sets the layout resource to create the drop down views.</p>
*
* @param resource the layout resource defining the drop down views
* @see #getDropDownView(int, android.view.View, android.view.ViewGroup)
*/
public void setDropDownViewResource(int resource) {
this.mDropDownResource = resource;
}
/**
* {@inheritDoc}
*/
@Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
return createViewFromResource(position, convertView, parent, mDropDownResource);
}
protected RelativeLayout inflateRowView(View convertView, int cellLayout) {
RelativeLayout row;
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(getContext());
row = (RelativeLayout)inflater.inflate(cellLayout, null);
} else {
row = (RelativeLayout)convertView;
}
return row;
}
}