/*
* 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 android.widget;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.view.LayoutInflater;
import android.net.Uri;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* An easy adapter to map static data to views defined in an XML file. You can specify the data
* backing the list as an ArrayList of Maps. Each entry in the ArrayList corresponds to one row
* in the list. The Maps contain the data for each row. You also specify an XML file that
* defines the views used to display the row, and a mapping from keys in the Map to specific
* views.
*
* Binding data to views occurs in two phases. First, if a
* {@link android.widget.SimpleAdapter.ViewBinder} is available,
* {@link ViewBinder#setViewValue(android.view.View, Object, String)}
* is invoked. If the returned value is true, binding has occurred.
* If the returned value is false, the following views are then tried in order:
* <ul>
* <li> A view that implements Checkable (e.g. CheckBox). The expected bind value is a boolean.
* <li> TextView. The expected bind value is a string and {@link #setViewText(TextView, String)}
* is invoked.
* <li> ImageView. The expected bind value is a resource id or a string and
* {@link #setViewImage(ImageView, int)} or {@link #setViewImage(ImageView, String)} is invoked.
* </ul>
* If no appropriate binding can be found, an {@link IllegalStateException} is thrown.
*/
public class SimpleAdapter extends BaseAdapter implements Filterable {
private int[] mTo;
private String[] mFrom;
private ViewBinder mViewBinder;
private List<? extends Map<String, ?>> mData;
private int mResource;
private int mDropDownResource;
private LayoutInflater mInflater;
private SimpleFilter mFilter;
private ArrayList<Map<String, ?>> mUnfilteredData;
/**
* Constructor
*
* @param context The context where the View associated with this SimpleAdapter is running
* @param data A List of Maps. Each entry in the List corresponds to one row in the list. The
* Maps contain the data for each row, and should include all the entries specified in
* "from"
* @param resource Resource identifier of a view layout that defines the views for this list
* item. The layout file should include at least those named views defined in "to"
* @param from A list of column names that will be added to the Map associated with each
* item.
* @param to The views that should display column in the "from" parameter. These should all be
* TextViews. The first N views in this list are given the values of the first N columns
* in the from parameter.
*/
public SimpleAdapter(Context context, List<? extends Map<String, ?>> data,
int resource, String[] from, int[] to) {
mData = data;
mResource = mDropDownResource = resource;
mFrom = from;
mTo = to;
mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
/**
* @see android.widget.Adapter#getCount()
*/
public int getCount() {
return mData.size();
}
/**
* @see android.widget.Adapter#getItem(int)
*/
public Object getItem(int position) {
return mData.get(position);
}
/**
* @see android.widget.Adapter#getItemId(int)
*/
public long getItemId(int position) {
return position;
}
/**
* @see android.widget.Adapter#getView(int, View, ViewGroup)
*/
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 v;
if (convertView == null) {
v = mInflater.inflate(resource, parent, false);
final int[] to = mTo;
final int count = to.length;
final View[] holder = new View[count];
for (int i = 0; i < count; i++) {
holder[i] = v.findViewById(to[i]);
}
v.setTag(holder);
} else {
v = convertView;
}
bindView(position, v);
return v;
}
/**
* <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;
}
@Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
return createViewFromResource(position, convertView, parent, mDropDownResource);
}
private void bindView(int position, View view) {
final Map dataSet = mData.get(position);
if (dataSet == null) {
return;
}
final ViewBinder binder = mViewBinder;
final View[] holder = (View[]) view.getTag();
final String[] from = mFrom;
final int[] to = mTo;
final int count = to.length;
for (int i = 0; i < count; i++) {
final View v = holder[i];
if (v != null) {
final Object data = dataSet.get(from[i]);
String text = data == null ? "" : data.toString();
if (text == null) {
text = "";
}
boolean bound = false;
if (binder != null) {
bound = binder.setViewValue(v, data, text);
}
if (!bound) {
if (v instanceof Checkable) {
if (data instanceof Boolean) {
((Checkable) v).setChecked((Boolean) data);
} else {
throw new IllegalStateException(v.getClass().getName() +
" should be bound to a Boolean, not a " + data.getClass());
}
} else if (v instanceof TextView) {
// Note: keep the instanceof TextView check at the bottom of these
// ifs since a lot of views are TextViews (e.g. CheckBoxes).
setViewText((TextView) v, text);
} else if (v instanceof ImageView) {
if (data instanceof Integer) {
setViewImage((ImageView) v, (Integer) data);
} else {
setViewImage((ImageView) v, text);
}
} else {
throw new IllegalStateException(v.getClass().getName() + " is not a " +
" view that can be bounds by this SimpleAdapter");
}
}
}
}
}
/**
* Returns the {@link ViewBinder} used to bind data to views.
*
* @return a ViewBinder or null if the binder does not exist
*
* @see #setViewBinder(android.widget.SimpleAdapter.ViewBinder)
*/
public ViewBinder getViewBinder() {
return mViewBinder;
}
/**
* Sets the binder used to bind data to views.
*
* @param viewBinder the binder used to bind data to views, can be null to
* remove the existing binder
*
* @see #getViewBinder()
*/
public void setViewBinder(ViewBinder viewBinder) {
mViewBinder = viewBinder;
}
/**
* Called by bindView() to set the image for an ImageView but only if
* there is no existing ViewBinder or if the existing ViewBinder cannot
* handle binding to an ImageView.
*
* This method is called instead of {@link #setViewImage(ImageView, String)}
* if the supplied data is an int or Integer.
*
* @param v ImageView to receive an image
* @param value the value retrieved from the data set
*
* @see #setViewImage(ImageView, String)
*/
public void setViewImage(ImageView v, int value) {
v.setImageResource(value);
}
/**
* Called by bindView() to set the image for an ImageView but only if
* there is no existing ViewBinder or if the existing ViewBinder cannot
* handle binding to an ImageView.
*
* By default, the value will be treated as an image resource. If the
* value cannot be used as an image resource, the value is used as an
* image Uri.
*
* This method is called instead of {@link #setViewImage(ImageView, int)}
* if the supplied data is not an int or Integer.
*
* @param v ImageView to receive an image
* @param value the value retrieved from the data set
*
* @see #setViewImage(ImageView, int)
*/
public void setViewImage(ImageView v, String value) {
try {
v.setImageResource(Integer.parseInt(value));
} catch (NumberFormatException nfe) {
v.setImageURI(Uri.parse(value));
}
}
/**
* Called by bindView() to set the text for a TextView but only if
* there is no existing ViewBinder or if the existing ViewBinder cannot
* handle binding to an TextView.
*
* @param v TextView to receive text
* @param text the text to be set for the TextView
*/
public void setViewText(TextView v, String text) {
v.setText(text);
}
public Filter getFilter() {
if (mFilter == null) {
mFilter = new SimpleFilter();
}
return mFilter;
}
/**
* This class can be used by external clients of SimpleAdapter to bind
* values to views.
*
* You should use this class to bind values to views that are not
* directly supported by SimpleAdapter or to change the way binding
* occurs for views supported by SimpleAdapter.
*
* @see SimpleAdapter#setViewImage(ImageView, int)
* @see SimpleAdapter#setViewImage(ImageView, String)
* @see SimpleAdapter#setViewText(TextView, String)
*/
public static interface ViewBinder {
/**
* Binds the specified data to the specified view.
*
* When binding is handled by this ViewBinder, this method must return true.
* If this method returns false, SimpleAdapter will attempts to handle
* the binding on its own.
*
* @param view the view to bind the data to
* @param data the data to bind to the view
* @param textRepresentation a safe String representation of the supplied data:
* it is either the result of data.toString() or an empty String but it
* is never null
*
* @return true if the data was bound to the view, false otherwise
*/
boolean setViewValue(View view, Object data, String textRepresentation);
}
/**
* <p>An array filters constrains the content of the array adapter with
* a prefix. Each item that does not start with the supplied prefix
* is removed from the list.</p>
*/
private class SimpleFilter extends Filter {
@Override
protected FilterResults performFiltering(CharSequence prefix) {
FilterResults results = new FilterResults();
if (mUnfilteredData == null) {
mUnfilteredData = new ArrayList<Map<String, ?>>(mData);
}
if (prefix == null || prefix.length() == 0) {
ArrayList<Map<String, ?>> list = mUnfilteredData;
results.values = list;
results.count = list.size();
} else {
String prefixString = prefix.toString().toLowerCase();
ArrayList<Map<String, ?>> unfilteredValues = mUnfilteredData;
int count = unfilteredValues.size();
ArrayList<Map<String, ?>> newValues = new ArrayList<Map<String, ?>>(count);
for (int i = 0; i < count; i++) {
Map<String, ?> h = unfilteredValues.get(i);
if (h != null) {
int len = mTo.length;
for (int j=0; j<len; j++) {
String str = (String)h.get(mFrom[j]);
String[] words = str.split(" ");
int wordCount = words.length;
for (int k = 0; k < wordCount; k++) {
String word = words[k];
if (word.toLowerCase().startsWith(prefixString)) {
newValues.add(h);
break;
}
}
}
}
}
results.values = newValues;
results.count = newValues.size();
}
return results;
}
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
//noinspection unchecked
mData = (List<Map<String, ?>>) results.values;
if (results.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
}
}
}
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