Files
packages_apps_Messaging/src/com/android/messaging/ui/mediapicker/MediaPickerPanel.java
T
Mike Dodd 461a34b466 Initial checkin of AOSP Messaging app.
b/23110861

Change-Id: I9aa980d7569247d6b2ca78f5dcb4502e1eaadb8a
2015-08-12 08:58:28 -07:00

564 lines
23 KiB
Java

/*
* 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.messaging.ui.mediapicker;
import android.content.Context;
import android.content.res.Resources;
import android.os.Handler;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.LinearLayout;
import com.android.messaging.R;
import com.android.messaging.ui.PagingAwareViewPager;
import com.android.messaging.util.Assert;
import com.android.messaging.util.OsUtil;
import com.android.messaging.util.UiUtils;
/**
* Custom layout panel which makes the MediaPicker animations seamless and synchronized
* Designed to be very specific to the MediaPicker's usage
*/
public class MediaPickerPanel extends ViewGroup {
/**
* The window of time in which we might to decide to reinterpret the intent of a gesture.
*/
private static final long TOUCH_RECAPTURE_WINDOW_MS = 500L;
// The two view components to layout
private LinearLayout mTabStrip;
private boolean mFullScreenOnly;
private PagingAwareViewPager mViewPager;
/**
* True if the MediaPicker is full screen or animating into it
*/
private boolean mFullScreen;
/**
* True if the MediaPicker is open at all
*/
private boolean mExpanded;
/**
* The current desired height of the MediaPicker. This property may be animated and the
* measure pass uses it to determine what size the components are.
*/
private int mCurrentDesiredHeight;
private final Handler mHandler = new Handler();
/**
* The media picker for dispatching events to the MediaPicker's listener
*/
private MediaPicker mMediaPicker;
/**
* The computed default "half-screen" height of the view pager in px
*/
private final int mDefaultViewPagerHeight;
/**
* The action bar height used to compute the padding on the view pager when it's full screen.
*/
private final int mActionBarHeight;
private TouchHandler mTouchHandler;
static final int PAGE_NOT_SET = -1;
public MediaPickerPanel(final Context context, final AttributeSet attrs) {
super(context, attrs);
// Cache the computed dimension
mDefaultViewPagerHeight = getResources().getDimensionPixelSize(
R.dimen.mediapicker_default_chooser_height);
mActionBarHeight = getResources().getDimensionPixelSize(R.dimen.action_bar_height);
}
@Override
protected void onFinishInflate() {
super.onFinishInflate();
mTabStrip = (LinearLayout) findViewById(R.id.mediapicker_tabstrip);
mViewPager = (PagingAwareViewPager) findViewById(R.id.mediapicker_view_pager);
mTouchHandler = new TouchHandler();
setOnTouchListener(mTouchHandler);
mViewPager.setOnTouchListener(mTouchHandler);
// Make sure full screen mode is updated in landscape mode change when the panel is open.
addOnLayoutChangeListener(new OnLayoutChangeListener() {
private boolean mLandscapeMode = UiUtils.isLandscapeMode();
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom,
int oldLeft, int oldTop, int oldRight, int oldBottom) {
final boolean newLandscapeMode = UiUtils.isLandscapeMode();
if (mLandscapeMode != newLandscapeMode) {
mLandscapeMode = newLandscapeMode;
if (mExpanded) {
setExpanded(mExpanded, false /* animate */, mViewPager.getCurrentItem(),
true /* force */);
}
}
}
});
}
@Override
protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) {
int requestedHeight = MeasureSpec.getSize(heightMeasureSpec);
if (mMediaPicker.getChooserShowsActionBarInFullScreen()) {
requestedHeight -= mActionBarHeight;
}
int desiredHeight = Math.min(mCurrentDesiredHeight, requestedHeight);
if (mExpanded && desiredHeight == 0) {
// If we want to be shown, we have to have a non-0 height. Returning a height of 0 will
// cause the framework to abort the animation from 0, so we must always have some
// height once we start expanding
desiredHeight = 1;
} else if (!mExpanded && desiredHeight == 0) {
mViewPager.setVisibility(View.GONE);
mViewPager.setAdapter(null);
}
measureChild(mTabStrip, widthMeasureSpec, heightMeasureSpec);
int tabStripHeight;
if (requiresFullScreen()) {
// Ensure that the tab strip is always visible, even in full screen.
tabStripHeight = mTabStrip.getMeasuredHeight();
} else {
// Slide out the tab strip at the end of the animation to full screen.
tabStripHeight = Math.min(mTabStrip.getMeasuredHeight(),
requestedHeight - desiredHeight);
}
// If we are animating and have an interim desired height, use the default height. We can't
// take the max here as on some devices the mDefaultViewPagerHeight may be too big in
// landscape mode after animation.
final int tabAdjustedDesiredHeight = desiredHeight - tabStripHeight;
final int viewPagerHeight =
tabAdjustedDesiredHeight <= 1 ? mDefaultViewPagerHeight : tabAdjustedDesiredHeight;
int viewPagerHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
viewPagerHeight, MeasureSpec.EXACTLY);
measureChild(mViewPager, widthMeasureSpec, viewPagerHeightMeasureSpec);
setMeasuredDimension(mViewPager.getMeasuredWidth(), desiredHeight);
}
@Override
protected void onLayout(final boolean changed, final int left, final int top, final int right,
final int bottom) {
int y = top;
final int width = right - left;
final int viewPagerHeight = mViewPager.getMeasuredHeight();
mViewPager.layout(0, y, width, y + viewPagerHeight);
y += viewPagerHeight;
mTabStrip.layout(0, y, width, y + mTabStrip.getMeasuredHeight());
}
void onChooserChanged() {
if (mFullScreen) {
setDesiredHeight(getDesiredHeight(), true);
}
}
void setFullScreenOnly(boolean fullScreenOnly) {
mFullScreenOnly = fullScreenOnly;
}
boolean isFullScreen() {
return mFullScreen;
}
void setMediaPicker(final MediaPicker mediaPicker) {
mMediaPicker = mediaPicker;
}
/**
* Get the desired height of the media picker panel for when the panel is not in motion (i.e.
* not being dragged by the user).
*/
private int getDesiredHeight() {
if (mFullScreen) {
int fullHeight = getContext().getResources().getDisplayMetrics().heightPixels;
if (OsUtil.isAtLeastKLP() && isAttachedToWindow()) {
// When we're attached to the window, we can get an accurate height, not necessary
// on older API level devices because they don't include the action bar height
View composeContainer =
getRootView().findViewById(R.id.conversation_and_compose_container);
if (composeContainer != null) {
// protect against composeContainer having been unloaded already
fullHeight -= UiUtils.getMeasuredBoundsOnScreen(composeContainer).top;
}
}
if (mMediaPicker.getChooserShowsActionBarInFullScreen()) {
return fullHeight - mActionBarHeight;
} else {
return fullHeight;
}
} else if (mExpanded) {
return LayoutParams.WRAP_CONTENT;
} else {
return 0;
}
}
private void setupViewPager(final int startingPage) {
mViewPager.setVisibility(View.VISIBLE);
if (startingPage >= 0 && startingPage < mMediaPicker.getPagerAdapter().getCount()) {
mViewPager.setAdapter(mMediaPicker.getPagerAdapter());
mViewPager.setCurrentItem(startingPage);
}
updateViewPager();
}
/**
* Expand the media picker panel. Since we always set the pager adapter to null when the panel
* is collapsed, we need to restore the adapter and the starting page.
* @param expanded expanded or collapsed
* @param animate need animation
* @param startingPage the desired selected page to start
*/
void setExpanded(final boolean expanded, final boolean animate, final int startingPage) {
setExpanded(expanded, animate, startingPage, false /* force */);
}
private void setExpanded(final boolean expanded, final boolean animate, final int startingPage,
final boolean force) {
if (expanded == mExpanded && !force) {
return;
}
mFullScreen = false;
mExpanded = expanded;
mHandler.post(new Runnable() {
@Override
public void run() {
setDesiredHeight(getDesiredHeight(), animate);
}
});
if (expanded) {
setupViewPager(startingPage);
mMediaPicker.dispatchOpened();
} else {
mMediaPicker.dispatchDismissed();
}
// Call setFullScreenView() when we are in landscape mode so it can go full screen as
// soon as it is expanded.
if (expanded && requiresFullScreen()) {
setFullScreenView(true, animate);
}
}
private boolean requiresFullScreen() {
return mFullScreenOnly || UiUtils.isLandscapeMode();
}
private void setDesiredHeight(int height, final boolean animate) {
final int startHeight = mCurrentDesiredHeight;
if (height == LayoutParams.WRAP_CONTENT) {
height = measureHeight();
}
clearAnimation();
if (animate) {
final int deltaHeight = height - startHeight;
final Animation animation = new Animation() {
@Override
protected void applyTransformation(final float interpolatedTime,
final Transformation t) {
mCurrentDesiredHeight = (int) (startHeight + deltaHeight * interpolatedTime);
requestLayout();
}
@Override
public boolean willChangeBounds() {
return true;
}
};
animation.setDuration(UiUtils.MEDIAPICKER_TRANSITION_DURATION);
animation.setInterpolator(UiUtils.EASE_OUT_INTERPOLATOR);
startAnimation(animation);
} else {
mCurrentDesiredHeight = height;
}
requestLayout();
}
/**
* @return The minimum total height of the view
*/
private int measureHeight() {
final int measureSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE, MeasureSpec.AT_MOST);
measureChild(mTabStrip, measureSpec, measureSpec);
return mDefaultViewPagerHeight + mTabStrip.getMeasuredHeight();
}
/**
* Enters or leaves full screen view
*
* @param fullScreen True to enter full screen view, false to leave
* @param animate True to animate the transition
*/
void setFullScreenView(final boolean fullScreen, final boolean animate) {
if (fullScreen == mFullScreen) {
return;
}
if (requiresFullScreen() && !fullScreen) {
setExpanded(false /* expanded */, true /* animate */, PAGE_NOT_SET);
return;
}
mFullScreen = fullScreen;
setDesiredHeight(getDesiredHeight(), animate);
mMediaPicker.dispatchFullScreen(mFullScreen);
updateViewPager();
}
/**
* ViewPager should have its paging disabled when in full screen mode.
*/
private void updateViewPager() {
mViewPager.setPagingEnabled(!mFullScreen);
}
@Override
public boolean onInterceptTouchEvent(final MotionEvent ev) {
return mTouchHandler.onInterceptTouchEvent(ev) || super.onInterceptTouchEvent(ev);
}
/**
* Helper class to handle touch events and swipe gestures
*/
private class TouchHandler implements OnTouchListener {
/**
* The height of the view when the touch press started
*/
private int mDownHeight = -1;
/**
* True if the panel moved at all (changed height) during the drag
*/
private boolean mMoved = false;
// The threshold constants converted from DP to px
private final float mFlingThresholdPx;
private final float mBigFlingThresholdPx;
// The system defined pixel size to determine when a movement is considered a drag.
private final int mTouchSlop;
/**
* A copy of the MotionEvent that started the drag/swipe gesture
*/
private MotionEvent mDownEvent;
/**
* Whether we are currently moving down. We may not be able to move down in full screen
* mode when the child view can swipe down (such as a list view).
*/
private boolean mMovedDown = false;
/**
* Indicates whether the child view contained in the panel can swipe down at the beginning
* of the drag event (i.e. the initial down). The MediaPanel can contain
* scrollable children such as a list view / grid view. If the child view can swipe down,
* We want to let the child view handle the scroll first instead of handling it ourselves.
*/
private boolean mCanChildViewSwipeDown = false;
/**
* Necessary direction ratio for a fling to be considered in one direction this prevents
* horizontal swipes with small vertical components from triggering vertical swipe actions
*/
private static final float DIRECTION_RATIO = 1.1f;
TouchHandler() {
final Resources resources = getContext().getResources();
final ViewConfiguration configuration = ViewConfiguration.get(getContext());
mFlingThresholdPx = resources.getDimensionPixelSize(
R.dimen.mediapicker_fling_threshold);
mBigFlingThresholdPx = resources.getDimensionPixelSize(
R.dimen.mediapicker_big_fling_threshold);
mTouchSlop = configuration.getScaledTouchSlop();
}
/**
* The media picker panel may contain scrollable children such as a GridView, which eats
* all touch events before we get to it. Therefore, we'd like to intercept these events
* before the children to determine if we should handle swiping down in full screen mode.
* In non-full screen mode, we should handle all vertical scrolling events and leave
* horizontal scrolling to the view pager.
*/
public boolean onInterceptTouchEvent(final MotionEvent ev) {
switch (ev.getActionMasked()) {
case MotionEvent.ACTION_DOWN:
// Never capture the initial down, so that the children may handle it
// as well. Let the touch handler know about the down event as well.
mTouchHandler.onTouch(MediaPickerPanel.this, ev);
// Ask the MediaPicker whether the contained view can be swiped down.
// We record the value at the start of the drag to decide the swiping mode
// for the entire motion.
mCanChildViewSwipeDown = mMediaPicker.canSwipeDownChooser();
return false;
case MotionEvent.ACTION_MOVE: {
if (mMediaPicker.isChooserHandlingTouch()) {
if (shouldAllowRecaptureTouch(ev)) {
mMediaPicker.stopChooserTouchHandling();
mViewPager.setPagingEnabled(true);
return false;
}
// If the chooser is claiming ownership on all touch events, then we
// shouldn't try to handle them (neither should the view pager).
mViewPager.setPagingEnabled(false);
return false;
} else if (mCanChildViewSwipeDown) {
// Never capture event if the child view can swipe down.
return false;
} else if (!mFullScreen && mMoved) {
// When we are not fullscreen, we own any vertical drag motion.
return true;
} else if (mMovedDown) {
// We are currently handling the down swipe ourselves, so always
// capture this event.
return true;
} else {
// The current interaction mode is undetermined, so always let the
// touch handler know about this event. However, don't capture this
// event so the child may handle it as well.
mTouchHandler.onTouch(MediaPickerPanel.this, ev);
// Capture the touch event from now on if we are handling the drag.
return mFullScreen ? mMovedDown : mMoved;
}
}
}
return false;
}
/**
* Determine whether we think the user is actually trying to expand or slide despite the
* fact that they touched first on a chooser that captured the input.
*/
private boolean shouldAllowRecaptureTouch(MotionEvent ev) {
final long elapsedMs = ev.getEventTime() - ev.getDownTime();
if (mDownEvent == null || elapsedMs == 0 || elapsedMs > TOUCH_RECAPTURE_WINDOW_MS) {
// Either we don't have info to decide or it's been long enough that we no longer
// want to reinterpret user intent.
return false;
}
final float dx = ev.getRawX() - mDownEvent.getRawX();
final float dy = ev.getRawY() - mDownEvent.getRawY();
final float dt = elapsedMs / 1000.0f;
final float maxAbsDelta = Math.max(Math.abs(dx), Math.abs(dy));
final float velocity = maxAbsDelta / dt;
return velocity > mFlingThresholdPx;
}
@Override
public boolean onTouch(final View view, final MotionEvent motionEvent) {
switch (motionEvent.getAction()) {
case MotionEvent.ACTION_UP: {
if (!mMoved || mDownEvent == null) {
return false;
}
final float dx = motionEvent.getRawX() - mDownEvent.getRawX();
final float dy = motionEvent.getRawY() - mDownEvent.getRawY();
final float dt =
(motionEvent.getEventTime() - mDownEvent.getEventTime()) / 1000.0f;
final float yVelocity = dy / dt;
boolean handled = false;
// Vertical swipe occurred if the direction is as least mostly in the y
// component and has the required velocity (px/sec)
if ((dx == 0 || (Math.abs(dy) / Math.abs(dx)) > DIRECTION_RATIO) &&
Math.abs(yVelocity) > mFlingThresholdPx) {
if (yVelocity < 0 && mExpanded) {
setFullScreenView(true, true);
handled = true;
} else if (yVelocity > 0) {
if (mFullScreen && yVelocity < mBigFlingThresholdPx) {
setFullScreenView(false, true);
} else {
setExpanded(false, true, PAGE_NOT_SET);
}
handled = true;
}
}
if (!handled) {
// If they didn't swipe enough, animate back to resting state
setDesiredHeight(getDesiredHeight(), true);
}
resetState();
break;
}
case MotionEvent.ACTION_DOWN: {
mDownHeight = getHeight();
mDownEvent = MotionEvent.obtain(motionEvent);
// If we are here and care about the return value (i.e. this is not called
// from onInterceptTouchEvent), then presumably no children view in the panel
// handles the down event. We'd like to handle future ACTION_MOVE events, so
// always claim ownership on this event so it doesn't fall through and gets
// cancelled by the framework.
return true;
}
case MotionEvent.ACTION_MOVE: {
if (mDownEvent == null) {
return mMoved;
}
final float dx = mDownEvent.getRawX() - motionEvent.getRawX();
final float dy = mDownEvent.getRawY() - motionEvent.getRawY();
// Don't act if the move is mostly horizontal
if (Math.abs(dy) > mTouchSlop &&
(Math.abs(dy) / Math.abs(dx)) > DIRECTION_RATIO) {
setDesiredHeight((int) (mDownHeight + dy), false);
mMoved = true;
if (dy < -mTouchSlop) {
mMovedDown = true;
}
}
return mMoved;
}
}
return mMoved;
}
private void resetState() {
mDownEvent = null;
mDownHeight = -1;
mMoved = false;
mMovedDown = false;
mCanChildViewSwipeDown = false;
updateViewPager();
}
}
}