| /* |
| * Copyright (C) 2015 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.calculator2; |
| |
| import android.content.Context; |
| import android.graphics.Color; |
| import android.support.v4.view.PagerAdapter; |
| import android.support.v4.view.ViewPager; |
| import android.util.AttributeSet; |
| import android.view.GestureDetector; |
| import android.view.MotionEvent; |
| import android.view.View; |
| import android.view.ViewGroup; |
| |
| public class CalculatorPadViewPager extends ViewPager { |
| |
| private final PagerAdapter mStaticPagerAdapter = new PagerAdapter() { |
| @Override |
| public int getCount() { |
| return getChildCount(); |
| } |
| |
| @Override |
| public View instantiateItem(ViewGroup container, final int position) { |
| final View child = getChildAt(position); |
| |
| // Set a OnClickListener to scroll to item's position when it isn't the current item. |
| child.setOnClickListener(new OnClickListener() { |
| @Override |
| public void onClick(View v) { |
| setCurrentItem(position, true /* smoothScroll */); |
| } |
| }); |
| // Set an OnTouchListener to always return true for onTouch events so that a touch |
| // sequence cannot pass through the item to the item below. |
| child.setOnTouchListener(new OnTouchListener() { |
| @Override |
| public boolean onTouch(View v, MotionEvent event) { |
| v.onTouchEvent(event); |
| return true; |
| } |
| }); |
| |
| // Set an OnHoverListener to always return true for onHover events so that focus cannot |
| // pass through the item to the item below. |
| child.setOnHoverListener(new OnHoverListener() { |
| @Override |
| public boolean onHover(View v, MotionEvent event) { |
| v.onHoverEvent(event); |
| return true; |
| } |
| }); |
| // Make the item focusable so it can be selected via a11y. |
| child.setFocusable(true); |
| // Set the content description of the item which will be used by a11y to identify it. |
| child.setContentDescription(getPageTitle(position)); |
| |
| return child; |
| } |
| |
| @Override |
| public void destroyItem(ViewGroup container, int position, Object object) { |
| removeViewAt(position); |
| } |
| |
| @Override |
| public boolean isViewFromObject(View view, Object object) { |
| return view == object; |
| } |
| |
| @Override |
| public float getPageWidth(int position) { |
| return position == 1 ? 7.0f / 9.0f : 1.0f; |
| } |
| |
| @Override |
| public CharSequence getPageTitle(int position) { |
| final String[] pageDescriptions = getContext().getResources() |
| .getStringArray(R.array.desc_pad_pages); |
| return pageDescriptions[position]; |
| } |
| }; |
| |
| private final OnPageChangeListener mOnPageChangeListener = new SimpleOnPageChangeListener() { |
| @Override |
| public void onPageSelected(int position) { |
| for (int i = getChildCount() - 1; i >= 0; --i) { |
| final View child = getChildAt(i); |
| // Only the "peeking" or covered page should be clickable. |
| child.setClickable(i != position); |
| |
| // Prevent clicks and accessibility focus from going through to descendants of |
| // other pages which are covered by the current page. |
| if (child instanceof ViewGroup) { |
| final ViewGroup childViewGroup = (ViewGroup) child; |
| for (int j = childViewGroup.getChildCount() - 1; j >= 0; --j) { |
| childViewGroup.getChildAt(j) |
| .setImportantForAccessibility(i == position |
| ? IMPORTANT_FOR_ACCESSIBILITY_AUTO |
| : IMPORTANT_FOR_ACCESSIBILITY_NO_HIDE_DESCENDANTS); |
| } |
| } |
| } |
| } |
| }; |
| |
| private final PageTransformer mPageTransformer = new PageTransformer() { |
| @Override |
| public void transformPage(View view, float position) { |
| if (position < 0.0f) { |
| // Pin the left page to the left side. |
| view.setTranslationX(getWidth() * -position); |
| view.setAlpha(Math.max(1.0f + position, 0.0f)); |
| } else { |
| // Use the default slide transition when moving to the next page. |
| view.setTranslationX(0.0f); |
| view.setAlpha(1.0f); |
| } |
| } |
| }; |
| |
| private final GestureDetector.SimpleOnGestureListener mGestureWatcher = |
| new GestureDetector.SimpleOnGestureListener() { |
| @Override |
| public boolean onDown(MotionEvent e) { |
| // Return true so calls to onSingleTapUp are not blocked. |
| return true; |
| } |
| |
| @Override |
| public boolean onSingleTapUp(MotionEvent ev) { |
| if (mClickedItemIndex != -1) { |
| getChildAt(mClickedItemIndex).performClick(); |
| mClickedItemIndex = -1; |
| return true; |
| } |
| return super.onSingleTapUp(ev); |
| } |
| }; |
| |
| private final GestureDetector mGestureDetector; |
| |
| private int mClickedItemIndex = -1; |
| |
| public CalculatorPadViewPager(Context context) { |
| this(context, null /* attrs */); |
| } |
| |
| public CalculatorPadViewPager(Context context, AttributeSet attrs) { |
| super(context, attrs); |
| |
| mGestureDetector = new GestureDetector(context, mGestureWatcher); |
| mGestureDetector.setIsLongpressEnabled(false); |
| |
| setAdapter(mStaticPagerAdapter); |
| setBackgroundColor(Color.BLACK); |
| setPageMargin(-getResources().getDimensionPixelSize(R.dimen.pad_page_margin)); |
| setPageTransformer(false, mPageTransformer); |
| addOnPageChangeListener(mOnPageChangeListener); |
| } |
| |
| @Override |
| protected void onFinishInflate() { |
| super.onFinishInflate(); |
| |
| // Invalidate the adapter's data set since children may have been added during inflation. |
| getAdapter().notifyDataSetChanged(); |
| |
| // Let page change listener know about our initial position. |
| mOnPageChangeListener.onPageSelected(getCurrentItem()); |
| } |
| |
| @Override |
| public boolean onInterceptTouchEvent(MotionEvent ev) { |
| // Always intercept touch events when a11y focused since otherwise they will be |
| // incorrectly offset by a11y before being dispatched to children. |
| boolean shouldIntercept = isAccessibilityFocused() || super.onInterceptTouchEvent(ev); |
| |
| // Only allow the current item to receive touch events. |
| if (!shouldIntercept && ev.getActionMasked() == MotionEvent.ACTION_DOWN) { |
| final int x = (int) ev.getX() + getScrollX(); |
| final int y = (int) ev.getY() + getScrollY(); |
| |
| // Reset the previously clicked item index. |
| mClickedItemIndex = -1; |
| |
| final int childCount = getChildCount(); |
| for (int i = childCount - 1; i >= 0; --i) { |
| final int childIndex = getChildDrawingOrder(childCount, i); |
| final View child = getChildAt(childIndex); |
| if (child.isAccessibilityFocused()) { |
| // If a child is a11y focused then we must always intercept the touch event |
| // since it will be incorrectly offset by a11y. |
| shouldIntercept = true; |
| mClickedItemIndex = childIndex; |
| break; |
| } else if (mClickedItemIndex == -1 |
| && child.getVisibility() == VISIBLE |
| && x >= child.getLeft() && x < child.getRight() |
| && y >= child.getTop() && y < child.getBottom()) { |
| shouldIntercept = childIndex != getCurrentItem(); |
| mClickedItemIndex = childIndex; |
| // continue; since another child may be a11y focused. |
| } |
| } |
| } |
| |
| return shouldIntercept; |
| } |
| |
| @Override |
| public boolean onTouchEvent(MotionEvent ev) { |
| // Allow both the gesture detector and super to handle the touch event so they both see |
| // the full sequence of events. This should be safe since the gesture detector only |
| // handle clicks and super only handles swipes. |
| mGestureDetector.onTouchEvent(ev); |
| return super.onTouchEvent(ev); |
| } |
| } |