// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package org.chromium.chrome.browser.tab;
import androidx.annotation.Nullable;
import org.jni_zero.NativeMethods;
import org.chromium.base.Callback;
import org.chromium.base.ObserverList.RewindableIterator;
import org.chromium.base.UserData;
import org.chromium.base.supplier.ObservableSupplier;
import org.chromium.cc.input.BrowserControlsOffsetTagsInfo;
import org.chromium.cc.input.BrowserControlsState;
import org.chromium.cc.input.OffsetTag;
import org.chromium.chrome.browser.flags.ChromeFeatureList;
import org.chromium.components.browser_ui.util.BrowserControlsVisibilityDelegate;
import org.chromium.content_public.browser.NavigationHandle;
import org.chromium.content_public.browser.WebContents;
import org.chromium.ui.base.WindowAndroid;
/** Manages the state of tab browser controls. */
public class TabBrowserControlsConstraintsHelper implements UserData {
private static final Class<TabBrowserControlsConstraintsHelper> USER_DATA_KEY =
TabBrowserControlsConstraintsHelper.class;
private final TabImpl mTab;
private final Callback<Integer> mConstraintsChangedCallback;
private long mNativeTabBrowserControlsConstraintsHelper; // Lazily initialized in |update|
private BrowserControlsVisibilityDelegate mVisibilityDelegate;
private @BrowserControlsState int mPreviousConstraints;
// This OffsetTag is used in:
// - Browser, to tag the layers that move with top controls to be moved by viz.
// - Renderer, to tag the corresponding scroll offset in the compositor frame's metadata.
// When visibility of the browser controls are forced by the browser, this token will be null.
private OffsetTag mTopControlsOffsetTag;
public static void createForTab(Tab tab) {
tab.getUserDataHost()
.setUserData(USER_DATA_KEY, new TabBrowserControlsConstraintsHelper(tab));
}
public static TabBrowserControlsConstraintsHelper get(Tab tab) {
return tab.getUserDataHost().getUserData(USER_DATA_KEY);
}
/**
* Returns the current visibility constraints for the display of browser controls.
* {@link BrowserControlsState} defines the valid return options.
* @param tab Tab whose browser controls state is looked into.
* @return The current visibility constraints.
*/
public static @BrowserControlsState int getConstraints(Tab tab) {
if (tab == null || get(tab) == null) return BrowserControlsState.BOTH;
return get(tab).getConstraints();
}
/**
* Returns the constraints delegate for a particular tab. The returned supplier will always be
* associated with that tab, even if it stops being the active tab.
* @param tab Tab whose browser controls state is looked into.
* @return Observable supplier for the current visibility constraints.
*/
public static ObservableSupplier<Integer> getObservableConstraints(Tab tab) {
if (tab == null) {
return null;
}
TabBrowserControlsConstraintsHelper helper = get(tab);
if (helper == null) {
return null;
}
return helper.mVisibilityDelegate;
}
/**
* Push state about whether or not the browser controls can show or hide to the renderer.
* @param tab Tab object.
*/
public static void updateEnabledState(Tab tab) {
if (tab == null || get(tab) == null) return;
get(tab).updateEnabledState();
}
/**
* Updates the browser controls state for this tab. As these values are set at the renderer
* level, there is potential for this impacting other tabs that might share the same
* process.
*
* @param tab Tab whose browser constrol state is looked into.
* @param current The desired current state for the controls. Pass
* {@link BrowserControlsState#BOTH} to preserve the current position.
* @param animate Whether the controls should animate to the specified ending condition or
* should jump immediately.
*/
public static void update(Tab tab, int current, boolean animate) {
if (tab == null || get(tab) == null) return;
get(tab).update(current, animate);
}
/** Constructor */
private TabBrowserControlsConstraintsHelper(Tab tab) {
mTab = (TabImpl) tab;
mConstraintsChangedCallback =
(constraints) -> {
updateEnabledState();
mPreviousConstraints = constraints;
};
mTab.addObserver(
new EmptyTabObserver() {
@Override
public void onInitialized(Tab tab, String appId) {
updateVisibilityDelegate();
}
@Override
public void onActivityAttachmentChanged(
Tab tab, @Nullable WindowAndroid window) {
if (window != null) updateVisibilityDelegate();
}
@Override
public void onDestroyed(Tab tab) {
tab.removeObserver(this);
}
private void updateAfterRendererProcessSwitch(Tab tab, boolean hasCommitted) {
int constraints = getConstraints();
if (constraints == BrowserControlsState.SHOWN
&& hasCommitted
&& TabBrowserControlsOffsetHelper.get(tab).topControlsOffset()
== 0) {
// If the browser controls were already fully visible on the previous
// page, then avoid an animation to keep the controls from jumping
// around.
update(BrowserControlsState.SHOWN, false);
} else {
updateEnabledState();
}
}
@Override
public void onDidFinishNavigationInPrimaryMainFrame(
Tab tab, NavigationHandle navigationHandle) {
// At this point, we might have switched renderer processes, so push the
// existing constraints to the new renderer (has the potential to be
// slightly spammy, but the renderer has logic to suppress duplicate
// calls).
updateAfterRendererProcessSwitch(tab, navigationHandle.hasCommitted());
}
@Override
public void onHidden(Tab tab, @TabHidingType int type) {
if (ChromeFeatureList.sBrowserControlsInViz.isEnabled()) {
unregisterOffsetTags();
}
}
@Override
public void onShown(Tab tab, @TabHidingType int type) {
if (ChromeFeatureList.sBrowserControlsInViz.isEnabled()) {
updateEnabledState();
}
}
@Override
public void onWebContentsSwapped(
Tab tab, boolean didStartLoad, boolean didFinishLoad) {
updateAfterRendererProcessSwitch(tab, true);
}
});
if (mTab.isInitialized() && !mTab.isDetached()) updateVisibilityDelegate();
}
@Override
public void destroy() {
if (mNativeTabBrowserControlsConstraintsHelper != 0) {
TabBrowserControlsConstraintsHelperJni.get()
.onDestroyed(
mNativeTabBrowserControlsConstraintsHelper,
TabBrowserControlsConstraintsHelper.this);
}
}
private void updateVisibilityDelegate() {
if (mVisibilityDelegate != null) {
mVisibilityDelegate.removeObserver(mConstraintsChangedCallback);
}
mVisibilityDelegate =
mTab.getDelegateFactory().createBrowserControlsVisibilityDelegate(mTab);
if (mVisibilityDelegate != null) {
mVisibilityDelegate.addObserver(mConstraintsChangedCallback);
}
}
private boolean isStateForced(int state) {
return state == BrowserControlsState.HIDDEN || state == BrowserControlsState.SHOWN;
}
private boolean wasPreviousStateForced() {
return isStateForced(mPreviousConstraints);
}
private void updateEnabledState() {
if (mTab.isFrozen()) return;
update(BrowserControlsState.BOTH, getConstraints() != BrowserControlsState.HIDDEN);
}
/** Unregister all OffsetTags (for now, only the top controls have an OffsetTag.) */
private void unregisterOffsetTags() {
updateOffsetTags(null, getConstraints());
}
private void updateOffsetTags(
OffsetTag newTopControlsOffsetTag, @BrowserControlsState int constraints) {
if (newTopControlsOffsetTag == mTopControlsOffsetTag) {
return;
}
RewindableIterator<TabObserver> observers = mTab.getTabObservers();
while (observers.hasNext()) {
observers
.next()
.onBrowserControlsConstraintsChanged(
mTab,
new BrowserControlsOffsetTagsInfo(mTopControlsOffsetTag),
new BrowserControlsOffsetTagsInfo(newTopControlsOffsetTag),
constraints);
}
mTopControlsOffsetTag = newTopControlsOffsetTag;
}
private void generateOffsetTags(
@BrowserControlsState int current, @BrowserControlsState int constraints) {
if (mTab.isHidden()) {
return;
}
boolean isNewStateForced = isStateForced(constraints);
if (mTopControlsOffsetTag == null && !isNewStateForced) {
updateOffsetTags(OffsetTag.createRandom(), constraints);
} else if (mTopControlsOffsetTag != null && isNewStateForced) {
updateOffsetTags(null, constraints);
}
}
/**
* Updates the browser controls state for this tab. As these values are set at the renderer
* level, there is potential for this impacting other tabs that might share the same process.
*
* @param current The desired current state for the controls. Pass {@link
* BrowserControlsState#BOTH} to preserve the current position.
* @param animate Whether the controls should animate to the specified ending condition or
* should jump immediately.
*/
public void update(int current, boolean animate) {
assert mTab.getWebContents() != null : "Shouldn't update a Tab with a null WebContents.";
int constraints = getConstraints();
// Do nothing if current and constraints conflict to avoid error in renderer.
if ((constraints == BrowserControlsState.HIDDEN && current == BrowserControlsState.SHOWN)
|| (constraints == BrowserControlsState.SHOWN
&& current == BrowserControlsState.HIDDEN)) {
return;
}
if (ChromeFeatureList.sBrowserControlsInViz.isEnabled()) {
generateOffsetTags(current, constraints);
}
if (current == BrowserControlsState.SHOWN || constraints == BrowserControlsState.SHOWN) {
mTab.willShowBrowserControls();
}
if (mNativeTabBrowserControlsConstraintsHelper == 0) {
mNativeTabBrowserControlsConstraintsHelper =
TabBrowserControlsConstraintsHelperJni.get()
.init(TabBrowserControlsConstraintsHelper.this);
}
TabBrowserControlsConstraintsHelperJni.get()
.updateState(
mNativeTabBrowserControlsConstraintsHelper,
TabBrowserControlsConstraintsHelper.this,
mTab.getWebContents(),
constraints,
current,
animate,
new BrowserControlsOffsetTagsInfo(mTopControlsOffsetTag));
}
private @BrowserControlsState int getConstraints() {
return mVisibilityDelegate == null ? BrowserControlsState.BOTH : mVisibilityDelegate.get();
}
public static void setForTesting(Tab tab, TabBrowserControlsConstraintsHelper helper) {
tab.getUserDataHost().setUserData(USER_DATA_KEY, helper);
}
@NativeMethods
interface Natives {
long init(TabBrowserControlsConstraintsHelper caller);
void onDestroyed(
long nativeTabBrowserControlsConstraintsHelper,
TabBrowserControlsConstraintsHelper caller);
void updateState(
long nativeTabBrowserControlsConstraintsHelper,
TabBrowserControlsConstraintsHelper caller,
WebContents webContents,
int contraints,
int current,
boolean animate,
BrowserControlsOffsetTagsInfo offsetTagsInfo);
}
}
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