/*
* Copyright (C) 2011 Google Inc.
* Licensed to 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 com.android.mailcommon;
import com.android.mailcommon.MergedAdapter.ListSpinnerAdapter;
import com.android.mailcommon.MergedAdapter.LocalAdapterPosition;
import android.content.Context;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.FrameLayout;
import android.widget.ListPopupWindow;
import android.widget.ListView;
/**
* <p>A spinner-like widget that combines data and views from multiple adapters (via MergedAdapter)
* and forwards certain events to those adapters. This widget also supports clickable but
* unselectable dropdown items, useful when displaying extra items that should not affect spinner
* selection state.</p>
*
* <p>The framework's Spinner widget can't be extended for this task because it uses a private list
* adapter (which prevents setting multiple item types) and hides access to its popup, which is
* useful for clients to know about (like when it's been opened).</p>
*
* <p>Clients must provide a set of adapters which the widget will use to load dropdown views,
* receive callbacks, and load the selected item's view.</p>
*
* <p>Apps incorporating this widget must declare a custom attribute: "dropDownWidth" under the
* "MultiAdapterSpinner" name as a "reference" format (see Gmail's attrs.xml file for an
* example). This attribute controls the width of the dropdown, similar to the attribute in the
* framework's Spinner widget.</p>
*
*/
public class MultiAdapterSpinner extends FrameLayout
implements AdapterView.OnItemClickListener, View.OnClickListener {
protected MergedAdapter<FancySpinnerAdapter> mAdapter;
protected ListPopupWindow mPopup;
private int mSelectedPosition = -1;
private Rect mTempRect = new Rect();
/**
* A basic adapter with some callbacks added so clients can be involved in spinner behavior.
*/
public interface FancySpinnerAdapter extends ListSpinnerAdapter {
/**
* Whether or not an item at position should become the new selected spinner item and change
* the spinner item view.
*/
boolean canSelect(int position);
/**
* Handle a click on an enabled item.
*/
void onClick(int position);
/**
* Fired when the popup window is about to be displayed.
*/
void onShowPopup();
}
private static class MergedSpinnerAdapter extends MergedAdapter<FancySpinnerAdapter> {
/**
* ListPopupWindow uses getView() but spinners return dropdown views in getDropDownView().
*/
@Override
public View getView(int position, View convertView, ViewGroup parent) {
return super.getDropDownView(position, convertView, parent);
}
}
public MultiAdapterSpinner(Context context) {
this(context, null);
}
public MultiAdapterSpinner(Context context, AttributeSet attrs) {
super(context, attrs);
mAdapter = new MergedSpinnerAdapter();
mPopup = new ListPopupWindow(context, attrs);
mPopup.setAnchorView(this);
mPopup.setOnItemClickListener(this);
mPopup.setModal(true);
mPopup.setAdapter(mAdapter);
}
public void setAdapters(FancySpinnerAdapter... adapters) {
mAdapter.setAdapters(adapters);
}
public void setSelectedItem(final FancySpinnerAdapter adapter, final int position) {
int globalPosition = 0;
boolean found = false;
for (int i = 0, count = mAdapter.getSubAdapterCount(); i < count; i++) {
ListSpinnerAdapter a = mAdapter.getSubAdapter(i);
if (a == adapter) {
globalPosition += position;
found = true;
break;
}
globalPosition += a.getCount();
}
if (found) {
if (adapter.canSelect(position)) {
removeAllViews();
View itemView = adapter.getView(position, null, this);
itemView.setClickable(true);
itemView.setOnClickListener(this);
addView(itemView);
if (position < adapter.getCount()) {
mSelectedPosition = globalPosition;
}
}
}
}
@Override
public void onClick(View v) {
if (!mPopup.isShowing()) {
for (int i = 0, count = mAdapter.getSubAdapterCount(); i < count; i++) {
mAdapter.getSubAdapter(i).onShowPopup();
}
final int spinnerPaddingLeft = getPaddingLeft();
final Drawable background = mPopup.getBackground();
int bgOffset = 0;
if (background != null) {
background.getPadding(mTempRect);
bgOffset = -mTempRect.left;
}
mPopup.setHorizontalOffset(bgOffset + spinnerPaddingLeft);
mPopup.show();
mPopup.getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
mPopup.setSelection(mSelectedPosition);
}
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if (position != mSelectedPosition) {
final LocalAdapterPosition<FancySpinnerAdapter> result =
mAdapter.getAdapterOffsetForItem(position);
if (result.mAdapter.canSelect(result.mLocalPosition)) {
mSelectedPosition = position;
} else {
mPopup.clearListSelection();
}
post(new Runnable() {
@Override
public void run() {
result.mAdapter.onClick(result.mLocalPosition);
}
});
}
mPopup.dismiss();
}
}