/*
* Copyright (C) 2013 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.photos;
import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.os.Handler;
import android.util.SparseBooleanArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.AnimationUtils;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.ListAdapter;
import android.widget.TextView;
import com.android.gallery3d.R;
public abstract class MultiSelectGridFragment extends Fragment
implements MultiChoiceManager.Delegate, AdapterView.OnItemClickListener {
final private Handler mHandler = new Handler();
final private Runnable mRequestFocus = new Runnable() {
@Override
public void run() {
mGrid.focusableViewAvailable(mGrid);
}
};
ListAdapter mAdapter;
GridView mGrid;
TextView mEmptyView;
View mProgressContainer;
View mGridContainer;
CharSequence mEmptyText;
boolean mGridShown;
MultiChoiceManager.Provider mHost;
public MultiSelectGridFragment() {
}
/**
* Provide default implementation to return a simple grid view. Subclasses
* can override to replace with their own layout. If doing so, the returned
* view hierarchy <em>must</em> have a GridView whose id is
* {@link android.R.id#grid android.R.id.list} and can optionally have a
* sibling text view id {@link android.R.id#empty android.R.id.empty} that
* is to be shown when the grid is empty.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.multigrid_content, container, false);
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
mHost = (MultiChoiceManager.Provider) activity;
if (mGrid != null) {
mGrid.setMultiChoiceModeListener(mHost.getMultiChoiceManager());
}
}
@Override
public void onDetach() {
super.onDetach();
mHost = null;
}
/**
* Attach to grid view once the view hierarchy has been created.
*/
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
ensureGrid();
}
/**
* Detach from grid view.
*/
@Override
public void onDestroyView() {
mHandler.removeCallbacks(mRequestFocus);
mGrid = null;
mGridShown = false;
mEmptyView = null;
mProgressContainer = mGridContainer = null;
super.onDestroyView();
}
/**
* This method will be called when an item in the grid is selected.
* Subclasses should override. Subclasses can call
* getGridView().getItemAtPosition(position) if they need to access the data
* associated with the selected item.
*
* @param g The GridView where the click happened
* @param v The view that was clicked within the GridView
* @param position The position of the view in the grid
* @param id The id of the item that was clicked
*/
public void onGridItemClick(GridView g, View v, int position, long id) {
}
/**
* Provide the cursor for the grid view.
*/
public void setAdapter(ListAdapter adapter) {
boolean hadAdapter = mAdapter != null;
mAdapter = adapter;
if (mGrid != null) {
mGrid.setAdapter(adapter);
if (!mGridShown && !hadAdapter) {
// The grid was hidden, and previously didn't have an
// adapter. It is now time to show it.
setGridShown(true, getView().getWindowToken() != null);
}
}
}
/**
* Set the currently selected grid item to the specified position with the
* adapter's data
*
* @param position
*/
public void setSelection(int position) {
ensureGrid();
mGrid.setSelection(position);
}
/**
* Get the position of the currently selected grid item.
*/
public int getSelectedItemPosition() {
ensureGrid();
return mGrid.getSelectedItemPosition();
}
/**
* Get the cursor row ID of the currently selected grid item.
*/
public long getSelectedItemId() {
ensureGrid();
return mGrid.getSelectedItemId();
}
/**
* Get the activity's grid view widget.
*/
public GridView getGridView() {
ensureGrid();
return mGrid;
}
/**
* The default content for a MultiSelectGridFragment has a TextView that can
* be shown when the grid is empty. If you would like to have it shown, call
* this method to supply the text it should use.
*/
public void setEmptyText(CharSequence text) {
ensureGrid();
if (mEmptyView == null) {
return;
}
mEmptyView.setText(text);
if (mEmptyText == null) {
mGrid.setEmptyView(mEmptyView);
}
mEmptyText = text;
}
/**
* Control whether the grid is being displayed. You can make it not
* displayed if you are waiting for the initial data to show in it. During
* this time an indeterminate progress indicator will be shown instead.
* <p>
* Applications do not normally need to use this themselves. The default
* behavior of MultiSelectGridFragment is to start with the grid not being
* shown, only showing it once an adapter is given with
* {@link #setAdapter(ListAdapter)}. If the grid at that point had not been
* shown, when it does get shown it will be do without the user ever seeing
* the hidden state.
*
* @param shown If true, the grid view is shown; if false, the progress
* indicator. The initial value is true.
*/
public void setGridShown(boolean shown) {
setGridShown(shown, true);
}
/**
* Like {@link #setGridShown(boolean)}, but no animation is used when
* transitioning from the previous state.
*/
public void setGridShownNoAnimation(boolean shown) {
setGridShown(shown, false);
}
/**
* Control whether the grid is being displayed. You can make it not
* displayed if you are waiting for the initial data to show in it. During
* this time an indeterminate progress indicator will be shown instead.
*
* @param shown If true, the grid view is shown; if false, the progress
* indicator. The initial value is true.
* @param animate If true, an animation will be used to transition to the
* new state.
*/
private void setGridShown(boolean shown, boolean animate) {
ensureGrid();
if (mProgressContainer == null) {
throw new IllegalStateException("Can't be used with a custom content view");
}
if (mGridShown == shown) {
return;
}
mGridShown = shown;
if (shown) {
if (animate) {
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_out));
mGridContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_in));
} else {
mProgressContainer.clearAnimation();
mGridContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.GONE);
mGridContainer.setVisibility(View.VISIBLE);
} else {
if (animate) {
mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_in));
mGridContainer.startAnimation(AnimationUtils.loadAnimation(
getActivity(), android.R.anim.fade_out));
} else {
mProgressContainer.clearAnimation();
mGridContainer.clearAnimation();
}
mProgressContainer.setVisibility(View.VISIBLE);
mGridContainer.setVisibility(View.GONE);
}
}
/**
* Get the ListAdapter associated with this activity's GridView.
*/
public ListAdapter getAdapter() {
return mGrid.getAdapter();
}
private void ensureGrid() {
if (mGrid != null) {
return;
}
View root = getView();
if (root == null) {
throw new IllegalStateException("Content view not yet created");
}
if (root instanceof GridView) {
mGrid = (GridView) root;
} else {
View empty = root.findViewById(android.R.id.empty);
if (empty != null && empty instanceof TextView) {
mEmptyView = (TextView) empty;
}
mProgressContainer = root.findViewById(R.id.progressContainer);
mGridContainer = root.findViewById(R.id.gridContainer);
View rawGridView = root.findViewById(android.R.id.list);
if (!(rawGridView instanceof GridView)) {
throw new RuntimeException(
"Content has view with id attribute 'android.R.id.list' "
+ "that is not a GridView class");
}
mGrid = (GridView) rawGridView;
if (mGrid == null) {
throw new RuntimeException(
"Your content must have a GridView whose id attribute is " +
"'android.R.id.list'");
}
if (mEmptyView != null) {
mGrid.setEmptyView(mEmptyView);
}
}
mGridShown = true;
mGrid.setOnItemClickListener(this);
mGrid.setMultiChoiceModeListener(mHost.getMultiChoiceManager());
if (mAdapter != null) {
ListAdapter adapter = mAdapter;
mAdapter = null;
setAdapter(adapter);
} else {
// We are starting without an adapter, so assume we won't
// have our data right away and start with the progress indicator.
if (mProgressContainer != null) {
setGridShown(false, false);
}
}
mHandler.post(mRequestFocus);
}
@Override
public Object getItemAtPosition(int position) {
return getAdapter().getItem(position);
}
@Override
public Object getPathForItemAtPosition(int position) {
return getPathForItem(getItemAtPosition(position));
}
@Override
public SparseBooleanArray getSelectedItemPositions() {
return mGrid.getCheckedItemPositions();
}
@Override
public int getSelectedItemCount() {
return mGrid.getCheckedItemCount();
}
public abstract Object getPathForItem(Object item);
@Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
onGridItemClick((GridView) parent, v, position, id);
}
}