Java tutorial
/* 50AH-code ========= 50 Android Hacks (http://manning.com/sessa/) book source code Copyright (c) 2012 Manning Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /* * Copyright (C) 2011 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.actionbarsherlock.widget; import android.os.Build; import com.actionbarsherlock.R; import com.actionbarsherlock.internal.widget.IcsLinearLayout; import com.actionbarsherlock.internal.widget.IcsListPopupWindow; import com.actionbarsherlock.view.ActionProvider; import com.actionbarsherlock.widget.ActivityChooserModel.ActivityChooserModelClient; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.content.pm.ResolveInfo; import android.content.res.Resources; import android.content.res.TypedArray; import android.database.DataSetObserver; import android.graphics.drawable.Drawable; import android.util.AttributeSet; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.ViewTreeObserver; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.widget.AdapterView; import android.widget.BaseAdapter; import android.widget.FrameLayout; import android.widget.ImageView; import android.widget.PopupWindow; import android.widget.TextView; /** * This class is a view for choosing an activity for handling a given {@link Intent}. * <p> * The view is composed of two adjacent buttons: * <ul> * <li> * The left button is an immediate action and allows one click activity choosing. * Tapping this button immediately executes the intent without requiring any further * user input. Long press on this button shows a popup for changing the default * activity. * </li> * <li> * The right button is an overflow action and provides an optimized menu * of additional activities. Tapping this button shows a popup anchored to this * view, listing the most frequently used activities. This list is initially * limited to a small number of items in frequency used order. The last item, * "Show all..." serves as an affordance to display all available activities. * </li> * </ul> * </p> * * @hide */ class ActivityChooserView extends ViewGroup implements ActivityChooserModelClient { /** * An adapter for displaying the activities in an {@link AdapterView}. */ private final ActivityChooserViewAdapter mAdapter; /** * Implementation of various interfaces to avoid publishing them in the APIs. */ private final Callbacks mCallbacks; /** * The content of this view. */ private final IcsLinearLayout mActivityChooserContent; /** * Stores the background drawable to allow hiding and latter showing. */ private final Drawable mActivityChooserContentBackground; /** * The expand activities action button; */ private final FrameLayout mExpandActivityOverflowButton; /** * The image for the expand activities action button; */ private final ImageView mExpandActivityOverflowButtonImage; /** * The default activities action button; */ private final FrameLayout mDefaultActivityButton; /** * The image for the default activities action button; */ private final ImageView mDefaultActivityButtonImage; /** * The maximal width of the list popup. */ private final int mListPopupMaxWidth; /** * The ActionProvider hosting this view, if applicable. */ ActionProvider mProvider; /** * Observer for the model data. */ private final DataSetObserver mModelDataSetOberver = new DataSetObserver() { @Override public void onChanged() { super.onChanged(); mAdapter.notifyDataSetChanged(); } @Override public void onInvalidated() { super.onInvalidated(); mAdapter.notifyDataSetInvalidated(); } }; private final OnGlobalLayoutListener mOnGlobalLayoutListener = new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { if (isShowingPopup()) { if (!isShown()) { getListPopupWindow().dismiss(); } else { getListPopupWindow().show(); if (mProvider != null) { mProvider.subUiVisibilityChanged(true); } } } } }; /** * Popup window for showing the activity overflow list. */ private IcsListPopupWindow mListPopupWindow; /** * Listener for the dismissal of the popup/alert. */ private PopupWindow.OnDismissListener mOnDismissListener; /** * Flag whether a default activity currently being selected. */ private boolean mIsSelectingDefaultActivity; /** * The count of activities in the popup. */ private int mInitialActivityCount = ActivityChooserViewAdapter.MAX_ACTIVITY_COUNT_DEFAULT; /** * Flag whether this view is attached to a window. */ private boolean mIsAttachedToWindow; /** * String resource for formatting content description of the default target. */ private int mDefaultActionButtonContentDescription; private final Context mContext; /** * Create a new instance. * * @param context The application environment. */ public ActivityChooserView(Context context) { this(context, null); } /** * Create a new instance. * * @param context The application environment. * @param attrs A collection of attributes. */ public ActivityChooserView(Context context, AttributeSet attrs) { this(context, attrs, 0); } /** * Create a new instance. * * @param context The application environment. * @param attrs A collection of attributes. * @param defStyle The default style to apply to this view. */ public ActivityChooserView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); mContext = context; TypedArray attributesArray = context.obtainStyledAttributes(attrs, R.styleable.SherlockActivityChooserView, defStyle, 0); mInitialActivityCount = attributesArray.getInt(R.styleable.SherlockActivityChooserView_initialActivityCount, ActivityChooserViewAdapter.MAX_ACTIVITY_COUNT_DEFAULT); Drawable expandActivityOverflowButtonDrawable = attributesArray .getDrawable(R.styleable.SherlockActivityChooserView_expandActivityOverflowButtonDrawable); attributesArray.recycle(); LayoutInflater inflater = LayoutInflater.from(mContext); inflater.inflate(R.layout.abs__activity_chooser_view, this, true); mCallbacks = new Callbacks(); mActivityChooserContent = (IcsLinearLayout) findViewById(R.id.abs__activity_chooser_view_content); mActivityChooserContentBackground = mActivityChooserContent.getBackground(); mDefaultActivityButton = (FrameLayout) findViewById(R.id.abs__default_activity_button); mDefaultActivityButton.setOnClickListener(mCallbacks); mDefaultActivityButton.setOnLongClickListener(mCallbacks); mDefaultActivityButtonImage = (ImageView) mDefaultActivityButton.findViewById(R.id.abs__image); mExpandActivityOverflowButton = (FrameLayout) findViewById(R.id.abs__expand_activities_button); mExpandActivityOverflowButton.setOnClickListener(mCallbacks); mExpandActivityOverflowButtonImage = (ImageView) mExpandActivityOverflowButton .findViewById(R.id.abs__image); mExpandActivityOverflowButtonImage.setImageDrawable(expandActivityOverflowButtonDrawable); mAdapter = new ActivityChooserViewAdapter(); mAdapter.registerDataSetObserver(new DataSetObserver() { @Override public void onChanged() { super.onChanged(); updateAppearance(); } }); Resources resources = context.getResources(); mListPopupMaxWidth = Math.max(resources.getDisplayMetrics().widthPixels / 2, resources.getDimensionPixelSize(R.dimen.abs__config_prefDialogWidth)); } /** * {@inheritDoc} */ public void setActivityChooserModel(ActivityChooserModel dataModel) { mAdapter.setDataModel(dataModel); if (isShowingPopup()) { dismissPopup(); showPopup(); } } /** * Sets the background for the button that expands the activity * overflow list. * * <strong>Note:</strong> Clients would like to set this drawable * as a clue about the action the chosen activity will perform. For * example, if a share activity is to be chosen the drawable should * give a clue that sharing is to be performed. * * @param drawable The drawable. */ public void setExpandActivityOverflowButtonDrawable(Drawable drawable) { mExpandActivityOverflowButtonImage.setImageDrawable(drawable); } /** * Sets the content description for the button that expands the activity * overflow list. * * description as a clue about the action performed by the button. * For example, if a share activity is to be chosen the content * description should be something like "Share with". * * @param resourceId The content description resource id. */ public void setExpandActivityOverflowButtonContentDescription(int resourceId) { CharSequence contentDescription = mContext.getString(resourceId); mExpandActivityOverflowButtonImage.setContentDescription(contentDescription); } /** * Set the provider hosting this view, if applicable. * @hide Internal use only */ public void setProvider(ActionProvider provider) { mProvider = provider; } /** * Shows the popup window with activities. * * @return True if the popup was shown, false if already showing. */ public boolean showPopup() { if (isShowingPopup() || !mIsAttachedToWindow) { return false; } mIsSelectingDefaultActivity = false; showPopupUnchecked(mInitialActivityCount); return true; } /** * Shows the popup no matter if it was already showing. * * @param maxActivityCount The max number of activities to display. */ private void showPopupUnchecked(int maxActivityCount) { if (mAdapter.getDataModel() == null) { throw new IllegalStateException("No data model. Did you call #setDataModel?"); } getViewTreeObserver().addOnGlobalLayoutListener(mOnGlobalLayoutListener); final boolean defaultActivityButtonShown = mDefaultActivityButton.getVisibility() == VISIBLE; final int activityCount = mAdapter.getActivityCount(); final int maxActivityCountOffset = defaultActivityButtonShown ? 1 : 0; if (maxActivityCount != ActivityChooserViewAdapter.MAX_ACTIVITY_COUNT_UNLIMITED && activityCount > maxActivityCount + maxActivityCountOffset) { mAdapter.setShowFooterView(true); mAdapter.setMaxActivityCount(maxActivityCount - 1); } else { mAdapter.setShowFooterView(false); mAdapter.setMaxActivityCount(maxActivityCount); } IcsListPopupWindow popupWindow = getListPopupWindow(); if (!popupWindow.isShowing()) { if (mIsSelectingDefaultActivity || !defaultActivityButtonShown) { mAdapter.setShowDefaultActivity(true, defaultActivityButtonShown); } else { mAdapter.setShowDefaultActivity(false, false); } final int contentWidth = Math.min(mAdapter.measureContentWidth(), mListPopupMaxWidth); popupWindow.setContentWidth(contentWidth); popupWindow.show(); if (mProvider != null) { mProvider.subUiVisibilityChanged(true); } popupWindow.getListView().setContentDescription( mContext.getString(R.string.abs__activitychooserview_choose_application)); } } /** * Dismisses the popup window with activities. * * @return True if dismissed, false if already dismissed. */ public boolean dismissPopup() { if (isShowingPopup()) { getListPopupWindow().dismiss(); ViewTreeObserver viewTreeObserver = getViewTreeObserver(); if (viewTreeObserver.isAlive()) { viewTreeObserver.removeGlobalOnLayoutListener(mOnGlobalLayoutListener); } } return true; } /** * Gets whether the popup window with activities is shown. * * @return True if the popup is shown. */ public boolean isShowingPopup() { return getListPopupWindow().isShowing(); } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); ActivityChooserModel dataModel = mAdapter.getDataModel(); if (dataModel != null) { dataModel.registerObserver(mModelDataSetOberver); } mIsAttachedToWindow = true; } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); ActivityChooserModel dataModel = mAdapter.getDataModel(); if (dataModel != null) { dataModel.unregisterObserver(mModelDataSetOberver); } ViewTreeObserver viewTreeObserver = getViewTreeObserver(); if (viewTreeObserver.isAlive()) { viewTreeObserver.removeGlobalOnLayoutListener(mOnGlobalLayoutListener); } mIsAttachedToWindow = false; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { View child = mActivityChooserContent; // If the default action is not visible we want to be as tall as the // ActionBar so if this widget is used in the latter it will look as // a normal action button. if (mDefaultActivityButton.getVisibility() != VISIBLE) { heightMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.getSize(heightMeasureSpec), MeasureSpec.EXACTLY); } measureChild(child, widthMeasureSpec, heightMeasureSpec); setMeasuredDimension(child.getMeasuredWidth(), child.getMeasuredHeight()); } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { mActivityChooserContent.layout(0, 0, right - left, bottom - top); if (getListPopupWindow().isShowing()) { showPopupUnchecked(mAdapter.getMaxActivityCount()); } else { dismissPopup(); } } public ActivityChooserModel getDataModel() { return mAdapter.getDataModel(); } /** * Sets a listener to receive a callback when the popup is dismissed. * * @param listener The listener to be notified. */ public void setOnDismissListener(PopupWindow.OnDismissListener listener) { mOnDismissListener = listener; } /** * Sets the initial count of items shown in the activities popup * i.e. the items before the popup is expanded. This is an upper * bound since it is not guaranteed that such number of intent * handlers exist. * * @param itemCount The initial popup item count. */ public void setInitialActivityCount(int itemCount) { mInitialActivityCount = itemCount; } /** * Sets a content description of the default action button. This * resource should be a string taking one formatting argument and * will be used for formatting the content description of the button * dynamically as the default target changes. For example, a resource * pointing to the string "share with %1$s" will result in a content * description "share with Bluetooth" for the Bluetooth activity. * * @param resourceId The resource id. */ public void setDefaultActionButtonContentDescription(int resourceId) { mDefaultActionButtonContentDescription = resourceId; } /** * Gets the list popup window which is lazily initialized. * * @return The popup. */ private IcsListPopupWindow getListPopupWindow() { if (mListPopupWindow == null) { mListPopupWindow = new IcsListPopupWindow(getContext()); mListPopupWindow.setAdapter(mAdapter); mListPopupWindow.setAnchorView(ActivityChooserView.this); mListPopupWindow.setModal(true); mListPopupWindow.setOnItemClickListener(mCallbacks); mListPopupWindow.setOnDismissListener(mCallbacks); } return mListPopupWindow; } /** * Updates the buttons state. */ private void updateAppearance() { // Expand overflow button. if (mAdapter.getCount() > 0) { mExpandActivityOverflowButton.setEnabled(true); } else { mExpandActivityOverflowButton.setEnabled(false); } // Default activity button. final int activityCount = mAdapter.getActivityCount(); final int historySize = mAdapter.getHistorySize(); if (activityCount > 0 && historySize > 0) { mDefaultActivityButton.setVisibility(VISIBLE); ResolveInfo activity = mAdapter.getDefaultActivity(); PackageManager packageManager = mContext.getPackageManager(); mDefaultActivityButtonImage.setImageDrawable(activity.loadIcon(packageManager)); if (mDefaultActionButtonContentDescription != 0) { CharSequence label = activity.loadLabel(packageManager); String contentDescription = mContext.getString(mDefaultActionButtonContentDescription, label); mDefaultActivityButton.setContentDescription(contentDescription); } } else { mDefaultActivityButton.setVisibility(View.GONE); } // Activity chooser content. if (mDefaultActivityButton.getVisibility() == VISIBLE) { mActivityChooserContent.setBackgroundDrawable(mActivityChooserContentBackground); } else { mActivityChooserContent.setBackgroundDrawable(null); } } /** * Interface implementation to avoid publishing them in the APIs. */ private class Callbacks implements AdapterView.OnItemClickListener, View.OnClickListener, View.OnLongClickListener, PopupWindow.OnDismissListener { // AdapterView#OnItemClickListener public void onItemClick(AdapterView<?> parent, View view, int position, long id) { ActivityChooserViewAdapter adapter = (ActivityChooserViewAdapter) parent.getAdapter(); final int itemViewType = adapter.getItemViewType(position); switch (itemViewType) { case ActivityChooserViewAdapter.ITEM_VIEW_TYPE_FOOTER: { showPopupUnchecked(ActivityChooserViewAdapter.MAX_ACTIVITY_COUNT_UNLIMITED); } break; case ActivityChooserViewAdapter.ITEM_VIEW_TYPE_ACTIVITY: { dismissPopup(); if (mIsSelectingDefaultActivity) { // The item at position zero is the default already. if (position > 0) { mAdapter.getDataModel().setDefaultActivity(position); } } else { // If the default target is not shown in the list, the first // item in the model is default action => adjust index position = mAdapter.getShowDefaultActivity() ? position : position + 1; Intent launchIntent = mAdapter.getDataModel().chooseActivity(position); if (launchIntent != null) { mContext.startActivity(launchIntent); } } } break; default: throw new IllegalArgumentException(); } } // View.OnClickListener public void onClick(View view) { if (view == mDefaultActivityButton) { dismissPopup(); ResolveInfo defaultActivity = mAdapter.getDefaultActivity(); final int index = mAdapter.getDataModel().getActivityIndex(defaultActivity); Intent launchIntent = mAdapter.getDataModel().chooseActivity(index); if (launchIntent != null) { mContext.startActivity(launchIntent); } } else if (view == mExpandActivityOverflowButton) { mIsSelectingDefaultActivity = false; showPopupUnchecked(mInitialActivityCount); } else { throw new IllegalArgumentException(); } } // OnLongClickListener#onLongClick @Override public boolean onLongClick(View view) { if (view == mDefaultActivityButton) { if (mAdapter.getCount() > 0) { mIsSelectingDefaultActivity = true; showPopupUnchecked(mInitialActivityCount); } } else { throw new IllegalArgumentException(); } return true; } // PopUpWindow.OnDismissListener#onDismiss public void onDismiss() { notifyOnDismissListener(); if (mProvider != null) { mProvider.subUiVisibilityChanged(false); } } private void notifyOnDismissListener() { if (mOnDismissListener != null) { mOnDismissListener.onDismiss(); } } } private static class SetActivated { public static void invoke(View view, boolean activated) { view.setActivated(activated); } } private static final boolean IS_HONEYCOMB = Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB; /** * Adapter for backing the list of activities shown in the popup. */ private class ActivityChooserViewAdapter extends BaseAdapter { public static final int MAX_ACTIVITY_COUNT_UNLIMITED = Integer.MAX_VALUE; public static final int MAX_ACTIVITY_COUNT_DEFAULT = 4; private static final int ITEM_VIEW_TYPE_ACTIVITY = 0; private static final int ITEM_VIEW_TYPE_FOOTER = 1; private static final int ITEM_VIEW_TYPE_COUNT = 3; private ActivityChooserModel mDataModel; private int mMaxActivityCount = MAX_ACTIVITY_COUNT_DEFAULT; private boolean mShowDefaultActivity; private boolean mHighlightDefaultActivity; private boolean mShowFooterView; public void setDataModel(ActivityChooserModel dataModel) { ActivityChooserModel oldDataModel = mAdapter.getDataModel(); if (oldDataModel != null && isShown()) { oldDataModel.unregisterObserver(mModelDataSetOberver); } mDataModel = dataModel; if (dataModel != null && isShown()) { dataModel.registerObserver(mModelDataSetOberver); } notifyDataSetChanged(); } @Override public int getItemViewType(int position) { if (mShowFooterView && position == getCount() - 1) { return ITEM_VIEW_TYPE_FOOTER; } else { return ITEM_VIEW_TYPE_ACTIVITY; } } @Override public int getViewTypeCount() { return ITEM_VIEW_TYPE_COUNT; } public int getCount() { int count = 0; int activityCount = mDataModel.getActivityCount(); if (!mShowDefaultActivity && mDataModel.getDefaultActivity() != null) { activityCount--; } count = Math.min(activityCount, mMaxActivityCount); if (mShowFooterView) { count++; } return count; } public Object getItem(int position) { final int itemViewType = getItemViewType(position); switch (itemViewType) { case ITEM_VIEW_TYPE_FOOTER: return null; case ITEM_VIEW_TYPE_ACTIVITY: if (!mShowDefaultActivity && mDataModel.getDefaultActivity() != null) { position++; } return mDataModel.getActivity(position); default: throw new IllegalArgumentException(); } } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { final int itemViewType = getItemViewType(position); switch (itemViewType) { case ITEM_VIEW_TYPE_FOOTER: if (convertView == null || convertView.getId() != ITEM_VIEW_TYPE_FOOTER) { convertView = LayoutInflater.from(getContext()) .inflate(R.layout.abs__activity_chooser_view_list_item, parent, false); convertView.setId(ITEM_VIEW_TYPE_FOOTER); TextView titleView = (TextView) convertView.findViewById(R.id.abs__title); titleView.setText(mContext.getString(R.string.abs__activity_chooser_view_see_all)); } return convertView; case ITEM_VIEW_TYPE_ACTIVITY: if (convertView == null || convertView.getId() != R.id.abs__list_item) { convertView = LayoutInflater.from(getContext()) .inflate(R.layout.abs__activity_chooser_view_list_item, parent, false); } PackageManager packageManager = mContext.getPackageManager(); // Set the icon ImageView iconView = (ImageView) convertView.findViewById(R.id.abs__icon); ResolveInfo activity = (ResolveInfo) getItem(position); iconView.setImageDrawable(activity.loadIcon(packageManager)); // Set the title. TextView titleView = (TextView) convertView.findViewById(R.id.abs__title); titleView.setText(activity.loadLabel(packageManager)); if (IS_HONEYCOMB) { // Highlight the default. if (mShowDefaultActivity && position == 0 && mHighlightDefaultActivity) { SetActivated.invoke(convertView, true); } else { SetActivated.invoke(convertView, false); } } return convertView; default: throw new IllegalArgumentException(); } } public int measureContentWidth() { // The user may have specified some of the target not to be shown but we // want to measure all of them since after expansion they should fit. final int oldMaxActivityCount = mMaxActivityCount; mMaxActivityCount = MAX_ACTIVITY_COUNT_UNLIMITED; int contentWidth = 0; View itemView = null; final int widthMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); final int heightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); final int count = getCount(); for (int i = 0; i < count; i++) { itemView = getView(i, itemView, null); itemView.measure(widthMeasureSpec, heightMeasureSpec); contentWidth = Math.max(contentWidth, itemView.getMeasuredWidth()); } mMaxActivityCount = oldMaxActivityCount; return contentWidth; } public void setMaxActivityCount(int maxActivityCount) { if (mMaxActivityCount != maxActivityCount) { mMaxActivityCount = maxActivityCount; notifyDataSetChanged(); } } public ResolveInfo getDefaultActivity() { return mDataModel.getDefaultActivity(); } public void setShowFooterView(boolean showFooterView) { if (mShowFooterView != showFooterView) { mShowFooterView = showFooterView; notifyDataSetChanged(); } } public int getActivityCount() { return mDataModel.getActivityCount(); } public int getHistorySize() { return mDataModel.getHistorySize(); } public int getMaxActivityCount() { return mMaxActivityCount; } public ActivityChooserModel getDataModel() { return mDataModel; } public void setShowDefaultActivity(boolean showDefaultActivity, boolean highlightDefaultActivity) { if (mShowDefaultActivity != showDefaultActivity || mHighlightDefaultActivity != highlightDefaultActivity) { mShowDefaultActivity = showDefaultActivity; mHighlightDefaultActivity = highlightDefaultActivity; notifyDataSetChanged(); } } public boolean getShowDefaultActivity() { return mShowDefaultActivity; } } }