/*
* Copyright (C) 2014 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.printspooler.widget;
import android.content.Context;
import android.support.v4.widget.ViewDragHelper;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.inputmethod.InputMethodManager;
import com.android.printspooler.R;
/**
* This class is a layout manager for the print screen. It has a sliding
* area that contains the print options. If the sliding area is open the
* print options are visible and if it is closed a summary of the print
* job is shown. Under the sliding area there is a place for putting
* arbitrary content such as preview, error message, progress indicator,
* etc. The sliding area is covering the content holder under it when
* the former is opened.
*/
@SuppressWarnings("unused")
public final class PrintContentView extends ViewGroup implements View.OnClickListener {
private static final int FIRST_POINTER_ID = 0;
private static final int ALPHA_MASK = 0xff000000;
private static final int ALPHA_SHIFT = 24;
private static final int COLOR_MASK = 0xffffff;
private final ViewDragHelper mDragger;
private final int mScrimColor;
private View mStaticContent;
private ViewGroup mSummaryContent;
private View mDynamicContent;
private View mDraggableContent;
private View mPrintButton;
private View mMoreOptionsButton;
private ViewGroup mOptionsContainer;
private View mEmbeddedContentContainer;
private View mEmbeddedContentScrim;
private View mExpandCollapseHandle;
private View mExpandCollapseIcon;
private int mClosedOptionsOffsetY;
private int mCurrentOptionsOffsetY = Integer.MIN_VALUE;
private OptionsStateChangeListener mOptionsStateChangeListener;
private OptionsStateController mOptionsStateController;
private int mOldDraggableHeight;
private float mDragProgress;
public interface OptionsStateChangeListener {
public void onOptionsOpened();
public void onOptionsClosed();
}
public interface OptionsStateController {
public boolean canOpenOptions();
public boolean canCloseOptions();
}
public PrintContentView(Context context, AttributeSet attrs) {
super(context, attrs);
mDragger = ViewDragHelper.create(this, new DragCallbacks());
mScrimColor = context.getColor(R.color.print_preview_scrim_color);
// The options view is sliding under the static header but appears
// after it in the layout, so we will draw in opposite order.
setChildrenDrawingOrderEnabled(true);
}
public void setOptionsStateChangeListener(OptionsStateChangeListener listener) {
mOptionsStateChangeListener = listener;
}
public void setOpenOptionsController(OptionsStateController controller) {
mOptionsStateController = controller;
}
public boolean isOptionsOpened() {
return mCurrentOptionsOffsetY == 0;
}
private boolean isOptionsClosed() {
return mCurrentOptionsOffsetY == mClosedOptionsOffsetY;
}
public void openOptions() {
if (isOptionsOpened()) {
return;
}
mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
getOpenedOptionsY());
invalidate();
}
public void closeOptions() {
if (isOptionsClosed()) {
return;
}
mDragger.smoothSlideViewTo(mDynamicContent, mDynamicContent.getLeft(),
getClosedOptionsY());
invalidate();
}
@Override
protected int getChildDrawingOrder(int childCount, int i) {
return childCount - i - 1;
}
@Override
protected void onFinishInflate() {
mStaticContent = findViewById(R.id.static_content);
mSummaryContent = (ViewGroup) findViewById(R.id.summary_content);
mDynamicContent = findViewById(R.id.dynamic_content);
mDraggableContent = findViewById(R.id.draggable_content);
mPrintButton = findViewById(R.id.print_button);
mMoreOptionsButton = findViewById(R.id.more_options_button);
mOptionsContainer = (ViewGroup) findViewById(R.id.options_container);
mEmbeddedContentContainer = findViewById(R.id.embedded_content_container);
mEmbeddedContentScrim = findViewById(R.id.embedded_content_scrim);
mExpandCollapseHandle = findViewById(R.id.expand_collapse_handle);
mExpandCollapseIcon = findViewById(R.id.expand_collapse_icon);
mExpandCollapseHandle.setOnClickListener(this);
mSummaryContent.setOnClickListener(this);
// Make sure we start in a closed options state.
onDragProgress(1.0f);
// The framework gives focus to the frist focusable and we
// do not want that, hence we will take focus instead.
setFocusableInTouchMode(true);
}
@Override
public void focusableViewAvailable(View v) {
// The framework gives focus to the frist focusable and we
// do not want that, hence do not announce new focusables.
return;
}
@Override
public void onClick(View view) {
if (view == mExpandCollapseHandle || view == mSummaryContent) {
if (isOptionsClosed() && mOptionsStateController.canOpenOptions()) {
openOptions();
} else if (isOptionsOpened() && mOptionsStateController.canCloseOptions()) {
closeOptions();
} // else in open/close progress do nothing.
} else if (view == mEmbeddedContentScrim) {
if (isOptionsOpened() && mOptionsStateController.canCloseOptions()) {
closeOptions();
}
}
}
@Override
public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
/* do nothing */
}
@Override
public boolean onTouchEvent(MotionEvent event) {
mDragger.processTouchEvent(event);
return true;
}
@Override
public boolean onInterceptTouchEvent(MotionEvent event) {
return mDragger.shouldInterceptTouchEvent(event)
|| super.onInterceptTouchEvent(event);
}
@Override
public void computeScroll() {
if (mDragger.continueSettling(true)) {
postInvalidateOnAnimation();
}
}
private int computeScrimColor() {
final int baseAlpha = (mScrimColor & ALPHA_MASK) >>> ALPHA_SHIFT;
final int adjustedAlpha = (int) (baseAlpha * (1 - mDragProgress));
return adjustedAlpha << ALPHA_SHIFT | (mScrimColor & COLOR_MASK);
}
private int getOpenedOptionsY() {
return mStaticContent.getBottom();
}
private int getClosedOptionsY() {
return getOpenedOptionsY() + mClosedOptionsOffsetY;
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final boolean wasOpened = isOptionsOpened();
measureChild(mStaticContent, widthMeasureSpec, heightMeasureSpec);
if (mSummaryContent.getVisibility() != View.GONE) {
measureChild(mSummaryContent, widthMeasureSpec, heightMeasureSpec);
}
measureChild(mDynamicContent, widthMeasureSpec, heightMeasureSpec);
measureChild(mPrintButton, widthMeasureSpec, heightMeasureSpec);
// The height of the draggable content may change and if that happens
// we have to adjust the sliding area closed state offset.
mClosedOptionsOffsetY = mSummaryContent.getMeasuredHeight()
- mDraggableContent.getMeasuredHeight();
if (mCurrentOptionsOffsetY == Integer.MIN_VALUE) {
mCurrentOptionsOffsetY = mClosedOptionsOffsetY;
}
final int heightSize = MeasureSpec.getSize(heightMeasureSpec);
// The content host must be maximally large size that fits entirely
// on the screen when the options are collapsed.
ViewGroup.LayoutParams params = mEmbeddedContentContainer.getLayoutParams();
params.height = heightSize - mStaticContent.getMeasuredHeight()
- mSummaryContent.getMeasuredHeight() - mDynamicContent.getMeasuredHeight()
+ mDraggableContent.getMeasuredHeight();
// The height of the draggable content may change and if that happens
// we have to adjust the current offset to ensure the sliding area is
// at the correct position.
if (mOldDraggableHeight != mDraggableContent.getMeasuredHeight()) {
if (mOldDraggableHeight != 0) {
mCurrentOptionsOffsetY = wasOpened ? 0 : mClosedOptionsOffsetY;
}
mOldDraggableHeight = mDraggableContent.getMeasuredHeight();
}
// The content host can grow vertically as much as needed - we will be covering it.
final int hostHeightMeasureSpec = MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0);
measureChild(mEmbeddedContentContainer, widthMeasureSpec, hostHeightMeasureSpec);
setMeasuredDimension(resolveSize(MeasureSpec.getSize(widthMeasureSpec), widthMeasureSpec),
resolveSize(heightSize, heightMeasureSpec));
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
mStaticContent.layout(left, top, right, mStaticContent.getMeasuredHeight());
if (mSummaryContent.getVisibility() != View.GONE) {
mSummaryContent.layout(left, mStaticContent.getMeasuredHeight(), right,
mStaticContent.getMeasuredHeight() + mSummaryContent.getMeasuredHeight());
}
final int dynContentTop = mStaticContent.getMeasuredHeight() + mCurrentOptionsOffsetY;
final int dynContentBottom = dynContentTop + mDynamicContent.getMeasuredHeight();
mDynamicContent.layout(left, dynContentTop, right, dynContentBottom);
MarginLayoutParams params = (MarginLayoutParams) mPrintButton.getLayoutParams();
final int printButtonLeft;
if (getLayoutDirection() == View.LAYOUT_DIRECTION_LTR) {
printButtonLeft = right - mPrintButton.getMeasuredWidth() - params.getMarginStart();
} else {
printButtonLeft = left + params.getMarginStart();
}
final int printButtonTop = dynContentBottom - mPrintButton.getMeasuredHeight() / 2;
final int printButtonRight = printButtonLeft + mPrintButton.getMeasuredWidth();
final int printButtonBottom = printButtonTop + mPrintButton.getMeasuredHeight();
mPrintButton.layout(printButtonLeft, printButtonTop, printButtonRight, printButtonBottom);
final int embContentTop = mStaticContent.getMeasuredHeight() + mClosedOptionsOffsetY
+ mDynamicContent.getMeasuredHeight();
final int embContentBottom = embContentTop + mEmbeddedContentContainer.getMeasuredHeight();
mEmbeddedContentContainer.layout(left, embContentTop, right, embContentBottom);
}
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new ViewGroup.MarginLayoutParams(getContext(), attrs);
}
private void onDragProgress(float progress) {
if (Float.compare(mDragProgress, progress) == 0) {
return;
}
if ((mDragProgress == 0 && progress > 0)
|| (mDragProgress == 1.0f && progress < 1.0f)) {
mSummaryContent.setLayerType(View.LAYER_TYPE_HARDWARE, null);
mDraggableContent.setLayerType(View.LAYER_TYPE_HARDWARE, null);
mMoreOptionsButton.setLayerType(View.LAYER_TYPE_HARDWARE, null);
ensureImeClosedAndInputFocusCleared();
}
if ((mDragProgress > 0 && progress == 0)
|| (mDragProgress < 1.0f && progress == 1.0f)) {
mSummaryContent.setLayerType(View.LAYER_TYPE_NONE, null);
mDraggableContent.setLayerType(View.LAYER_TYPE_NONE, null);
mMoreOptionsButton.setLayerType(View.LAYER_TYPE_NONE, null);
mMoreOptionsButton.setLayerType(View.LAYER_TYPE_NONE, null);
}
mDragProgress = progress;
mSummaryContent.setAlpha(progress);
final float inverseAlpha = 1.0f - progress;
mOptionsContainer.setAlpha(inverseAlpha);
mMoreOptionsButton.setAlpha(inverseAlpha);
mEmbeddedContentScrim.setBackgroundColor(computeScrimColor());
if (progress == 0) {
if (mOptionsStateChangeListener != null) {
mOptionsStateChangeListener.onOptionsOpened();
}
mExpandCollapseHandle.setContentDescription(
mContext.getString(R.string.collapse_handle));
announceForAccessibility(mContext.getString(R.string.print_options_expanded));
mSummaryContent.setVisibility(View.GONE);
mEmbeddedContentScrim.setOnClickListener(this);
mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_less);
} else {
mSummaryContent.setVisibility(View.VISIBLE);
}
if (progress == 1.0f) {
if (mOptionsStateChangeListener != null) {
mOptionsStateChangeListener.onOptionsClosed();
}
mExpandCollapseHandle.setContentDescription(
mContext.getString(R.string.expand_handle));
announceForAccessibility(mContext.getString(R.string.print_options_collapsed));
if (mMoreOptionsButton.getVisibility() != View.GONE) {
mMoreOptionsButton.setVisibility(View.INVISIBLE);
}
mDraggableContent.setVisibility(View.INVISIBLE);
// If we change the scrim visibility the dimming is lagging
// and is janky. Now it is there but transparent, doing nothing.
mEmbeddedContentScrim.setOnClickListener(null);
mEmbeddedContentScrim.setClickable(false);
mExpandCollapseIcon.setBackgroundResource(R.drawable.ic_expand_more);
} else {
if (mMoreOptionsButton.getVisibility() != View.GONE) {
mMoreOptionsButton.setVisibility(View.VISIBLE);
}
mDraggableContent.setVisibility(View.VISIBLE);
}
}
private void ensureImeClosedAndInputFocusCleared() {
View focused = findFocus();
if (focused != null && focused.isFocused()) {
InputMethodManager imm = (InputMethodManager) mContext.getSystemService(
Context.INPUT_METHOD_SERVICE);
if (imm.isActive(focused)) {
imm.hideSoftInputFromWindow(getWindowToken(), 0);
}
focused.clearFocus();
}
}
private final class DragCallbacks extends ViewDragHelper.Callback {
@Override
public boolean tryCaptureView(View child, int pointerId) {
if (isOptionsOpened() && !mOptionsStateController.canCloseOptions()
|| isOptionsClosed() && !mOptionsStateController.canOpenOptions()) {
return false;
}
return child == mDynamicContent && pointerId == FIRST_POINTER_ID;
}
@Override
public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {
if ((isOptionsClosed() || isOptionsClosed()) && dy <= 0) {
return;
}
mCurrentOptionsOffsetY += dy;
final float progress = ((float) top - getOpenedOptionsY())
/ (getClosedOptionsY() - getOpenedOptionsY());
mPrintButton.offsetTopAndBottom(dy);
mDraggableContent.notifySubtreeAccessibilityStateChangedIfNeeded();
onDragProgress(progress);
}
@Override
public void onViewReleased(View child, float velocityX, float velocityY) {
final int childTop = child.getTop();
final int openedOptionsY = getOpenedOptionsY();
final int closedOptionsY = getClosedOptionsY();
if (childTop == openedOptionsY || childTop == closedOptionsY) {
return;
}
final int halfRange = closedOptionsY + (openedOptionsY - closedOptionsY) / 2;
if (childTop < halfRange) {
mDragger.smoothSlideViewTo(child, child.getLeft(), closedOptionsY);
} else {
mDragger.smoothSlideViewTo(child, child.getLeft(), openedOptionsY);
}
invalidate();
}
@Override
public int getOrderedChildIndex(int index) {
return getChildCount() - index - 1;
}
@Override
public int getViewVerticalDragRange(View child) {
return mDraggableContent.getHeight();
}
@Override
public int clampViewPositionVertical(View child, int top, int dy) {
final int staticOptionBottom = mStaticContent.getBottom();
return Math.max(Math.min(top, getOpenedOptionsY()), getClosedOptionsY());
}
}
}