// Copyright 2021 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.content.browser;
import static org.chromium.content_public.browser.HostZoomMap.TEXT_SIZE_MULTIPLIER_RATIO;
import static org.chromium.content_public.browser.HostZoomMap.getSystemFontScale;
import static org.chromium.content_public.browser.HostZoomMap.setSystemFontScale;
import org.jni_zero.CalledByNative;
import org.jni_zero.CalledByNativeForTesting;
import org.jni_zero.JNINamespace;
import org.jni_zero.JniType;
import org.jni_zero.NativeMethods;
import org.chromium.base.MathUtils;
import org.chromium.base.ResettersForTesting;
import org.chromium.content_public.browser.BrowserContextHandle;
import org.chromium.content_public.browser.ContentFeatureList;
import org.chromium.content_public.browser.ContentFeatureMap;
import org.chromium.content_public.browser.HostZoomMap;
import org.chromium.content_public.browser.SiteZoomInfo;
import org.chromium.content_public.browser.WebContents;
import java.util.HashMap;
/** Implementations of {@link HostZoomMap} */
@JNINamespace("content")
public class HostZoomMapImpl {
// Private constructor to prevent unwanted construction.
private HostZoomMapImpl() {}
/**
* Set a new zoom level for the given web contents.
* @param webContents WebContents to update
* @param newZoomLevel double - new zoom level
*/
public static void setZoomLevel(
WebContents webContents, double newZoomLevel, double adjustedZoomLevel) {
HostZoomMapImplJni.get().setZoomLevel(webContents, newZoomLevel, adjustedZoomLevel);
}
/**
* Set a new zoom level for the given host.
* @param host host url to update.
* @param level double - new zoom level.
* @param browserContextHandle BrowserContextHandle to update host zoom for.
*/
public static void setZoomLevelForHost(
BrowserContextHandle browserContextHandle, String host, double level) {
HostZoomMapImplJni.get().setZoomLevelForHost(browserContextHandle, host, level);
}
/**
* Gets zoom levels for all hosts.
* @param browserContextHandle BrowserContextHandle to get host zooms for.
*/
public static HashMap<String, Double> getAllHostZoomLevels(
BrowserContextHandle browserContextHandle) {
SiteZoomInfo[] siteZoomInfoList =
HostZoomMapImplJni.get().getAllHostZoomLevels(browserContextHandle);
HashMap<String, Double> hostToZoomLevel = new HashMap<>();
for (int i = 0; i < siteZoomInfoList.length; i++) {
hostToZoomLevel.put(siteZoomInfoList[i].host, siteZoomInfoList[i].zoomLevel);
}
return hostToZoomLevel;
}
/**
* Get the current zoom level for a given web contents.
* @param webContents WebContents to get zoom level for
* @return double current zoom level
*/
public static double getZoomLevel(WebContents webContents) {
return HostZoomMapImplJni.get().getZoomLevel(webContents);
}
/**
* Set the default zoom level for a given browser context handle (e.g. Profile).
* @param context BrowserContextHandle to update default for.
* @param newDefaultZoomLevel double, new default value.
*/
public static void setDefaultZoomLevel(
BrowserContextHandle context, double newDefaultZoomLevel) {
HostZoomMapImplJni.get().setDefaultZoomLevel(context, newDefaultZoomLevel);
}
/**
* Get the default zoom level for a given browser context handle (e.g. Profile).
* @param context BrowserContextHandle to get default for.
* @return double default zoom level.
*/
public static double getDefaultZoomLevel(BrowserContextHandle context) {
return HostZoomMapImplJni.get().getDefaultZoomLevel(context);
}
@CalledByNative
public static double getAdjustedZoomLevel(double zoomLevel) {
float systemFontScale = getSystemFontScale();
// The OS |fontScale| will not be factored in zoom estimation if Page Zoom is disabled; a
// systemFontScale = 1 will be used in this case.
if (!ContentFeatureMap.isEnabled(ContentFeatureList.ACCESSIBILITY_PAGE_ZOOM)
|| !shouldAdjustForOSLevel()) {
systemFontScale = 1;
}
return adjustZoomLevel(zoomLevel, systemFontScale);
}
@CalledByNative
public static SiteZoomInfo buildSiteZoomInfo(
@JniType("std::string") String host, double zoomLevel) {
return new SiteZoomInfo(host, zoomLevel);
}
/**
* Returns true when the field trial param to adjust zoom for OS-level font setting is true,
* false otherwise.
*
* <p>Note: The former text-autoscaling feature takes the OS-level font setting into account, so
* this will be included in any text-size-adjust changes. We default to false here so that we do
* not double-apply the setting.
*
* @return bool True if zoom should be adjusted.
*/
public static boolean shouldAdjustForOSLevel() {
return ContentFeatureMap.getInstance()
.getFieldTrialParamByFeatureAsBoolean(
ContentFeatureList.ACCESSIBILITY_PAGE_ZOOM,
ContentFeatureList.ACCESSIBILITY_PAGE_ZOOM_PARAM,
false);
}
/**
* Adjust a given zoom level to account for the OS-level |fontScale| configuration on Android.
*
* @param zoomLevel The zoom level to adjust.
* @param systemFontScale User selected font scale value.
* @return double The adjusted zoom level.
*/
public static double adjustZoomLevel(double zoomLevel, float systemFontScale) {
// No calculation to do if the user has set OS-level |fontScale| to 1 (default).
if (MathUtils.areFloatsEqual(systemFontScale, 1f) || !shouldAdjustForOSLevel()) {
return zoomLevel;
}
// Convert the zoom factor to a level, e.g. factor = 0.0 should translate to 1.0 (100%).
// Multiply the level by the OS-level |fontScale|. For example, if the user has chosen a
// Chrome-level zoom of 150%, and a OS-level setting of XL (130%), then we want to continue
// to display 150% to the user but actually render 1.5 * 1.3 = 1.95 (195%) zoom. We must
// apply this at the zoom level (not factor) to compensate for logarithmic scale.
double adjustedLevel = systemFontScale * Math.pow(TEXT_SIZE_MULTIPLIER_RATIO, zoomLevel);
// We do not pass levels to the backend, but factors. So convert back and round.
double adjustedFactor = Math.log10(adjustedLevel) / Math.log10(TEXT_SIZE_MULTIPLIER_RATIO);
return MathUtils.roundTwoDecimalPlaces(adjustedFactor);
}
@CalledByNativeForTesting
public static void setSystemFontScaleForTesting(float scale) {
var oldValue = getSystemFontScale();
setSystemFontScale(scale);
ResettersForTesting.register(() -> setSystemFontScale(oldValue));
}
@NativeMethods
public interface Natives {
void setZoomLevel(WebContents webContents, double newZoomLevel, double adjustedZoomLevel);
double getZoomLevel(WebContents webContents);
void setDefaultZoomLevel(BrowserContextHandle context, double newDefaultZoomLevel);
double getDefaultZoomLevel(BrowserContextHandle context);
@JniType("std::vector")
SiteZoomInfo[] getAllHostZoomLevels(BrowserContextHandle context);
void setZoomLevelForHost(BrowserContextHandle context, String host, double level);
}
}
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