diff --git a/chrome/android/BUILD.gn b/chrome/android/BUILD.gn
index a9d57e9265dad..199b5577ad7e5 100644
--- a/chrome/android/BUILD.gn
+++ b/chrome/android/BUILD.gn
@@ -312,6 +312,8 @@ if (_is_default_toolchain) {
android_library("chrome_java") {
deps = [
+ "//third_party/androidx:androidx_compose_ui_ui_android_java",
+ "//mica:ui_java",
":base_module_java",
":chrome_app_java_resources",
":chrome_public_apk_template_resources",
@@ -1803,6 +1805,10 @@ if (_is_default_toolchain) {
android_resources("chrome_public_apk_base_module_resources") {
resource_overlay = true
sources = [
+ "java/res_chromium_base/drawable/ic_launcher.xml",
+ "java/res_chromium_base/drawable/ic_launcher_round.xml",
+ "java/res_chromium_base/drawable/mica_launcher_foreground.xml",
+ "java/res_chromium_base/drawable/mica_launcher_foreground_monochrome.xml",
"java/res_chromium_base/drawable/themed_app_icon.xml",
"java/res_chromium_base/mipmap-hdpi/app_icon.png",
"java/res_chromium_base/mipmap-hdpi/layered_app_icon.png",
@@ -2109,6 +2115,7 @@ if (_is_default_toolchain) {
}
chrome_public_apk_or_module_tmpl("chrome_public_apk") {
+ loadable_modules = [ "//mica/libandroidx.graphics.path.so" ]
target_type = "android_apk"
apk_name = "ChromePublic"
if (defined(android_app_secondary_abi)) {
diff --git a/chrome/android/java/res_chromium_base/values/channel_constants.xml b/chrome/android/java/res_chromium_base/values/channel_constants.xml
index cc1f2a30cb3c5..68f69136657d0 100644
--- a/chrome/android/java/res_chromium_base/values/channel_constants.xml
+++ b/chrome/android/java/res_chromium_base/values/channel_constants.xml
@@ -7,8 +7,8 @@ found in the LICENSE file.
- Chromium
- Chromium bookmarks
- Chromium search
- Chromium quick action search
+ Mica
+ Mica bookmarks
+ Mica search
+ Mica quick action search
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java
index 411d05fc91a5e..eb388d4f1830c 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java
@@ -1669,6 +1669,13 @@ public class ChromeTabbedActivity extends ChromeActivity implements PreAttachInt
}
super.finishNativeInitialization();
+ // Force Chrome's own toolbar hidden via the real browser-controls state machine
+ // (not a one-off View.setVisibility hack) so it can never be re-shown by
+ // ToolbarManager on tab switch, navigation, or scroll. See installMicaUi() below,
+ // which embeds Chrome's content view (with its now-permanently-hidden toolbar)
+ // inside Mica's own Compose chrome.
+ getBrowserControlsManager().getBrowserVisibilityDelegate().setForceHidden(true);
+ getWindow().getDecorView().post(this::installMicaUi);
TabbedStartupWindowPolicyDelegate.getInstance().initializeWithNative(profile);
@@ -6105,4 +6112,129 @@ public class ChromeTabbedActivity extends ChromeActivity implements PreAttachInt
// future.
return VerticalTabUtils.isVerticalTabsEnabled(this);
}
+ private boolean mMicaInstalled;
+ private kotlin.jvm.functions.Function2 mMicaScrollCallback;
+ private org.chromium.content_public.browser.WebContents mMicaScrollWebContents;
+
+ /**
+ * Bridges real Chromium page-scroll gesture updates into Mica's ContentScrollListener. Uses
+ * the default (NONE) update frequency, which piggybacks on RenderFrameMetadata updates Chrome
+ * already sends during an active scroll rather than requesting extra IPC -- deliberately not a
+ * fake timer or Compose-only scroll simulation.
+ */
+ private final org.chromium.content_public.browser.GestureStateListener mMicaScrollGestureListener =
+ new org.chromium.content_public.browser.GestureStateListener() {
+ private int mLastOffsetY = -1;
+
+ @Override
+ public void onScrollOffsetOrExtentChanged(int scrollOffsetY, int scrollExtentY) {
+ if (mMicaScrollCallback == null) return;
+ if (mLastOffsetY < 0) {
+ mLastOffsetY = scrollOffsetY;
+ return;
+ }
+ // Positive when the page scrolls toward the top, matching
+ // ContentScrollListener's "finger moves down" sign convention.
+ float deltaY = mLastOffsetY - scrollOffsetY;
+ mLastOffsetY = scrollOffsetY;
+ if (deltaY != 0f) mMicaScrollCallback.invoke(deltaY, scrollOffsetY <= 0);
+ }
+
+ @Override
+ public void onScrollEnded(int scrollOffsetY, int scrollExtentY) {
+ mLastOffsetY = scrollOffsetY;
+ }
+ };
+
+ private void updateMicaScrollBridge() {
+ Tab tab = getActivityTab();
+ org.chromium.content_public.browser.WebContents webContents =
+ tab == null ? null : tab.getWebContents();
+ if (webContents == mMicaScrollWebContents) return;
+ if (mMicaScrollWebContents != null) {
+ org.chromium.content_public.browser.GestureListenerManager oldManager =
+ org.chromium.content_public.browser.GestureListenerManager.fromWebContents(
+ mMicaScrollWebContents);
+ if (oldManager != null) oldManager.removeListener(mMicaScrollGestureListener);
+ }
+ mMicaScrollWebContents = webContents;
+ if (mMicaScrollWebContents != null) {
+ org.chromium.content_public.browser.GestureListenerManager newManager =
+ org.chromium.content_public.browser.GestureListenerManager.fromWebContents(
+ mMicaScrollWebContents);
+ if (newManager != null) newManager.addListener(mMicaScrollGestureListener);
+ }
+ }
+
+ private void installMicaUi() {
+ if (mMicaInstalled || isFinishing() || isDestroyed()) return;
+ if (getActivityTab() == null) {
+ getWindow().getDecorView().postDelayed(this::installMicaUi, 100);
+ return;
+ }
+ mMicaInstalled = true;
+ getActivityTab().addObserver(new TabObserver() {
+ @Override
+ public void onContentChanged(Tab tab) {
+ updateMicaScrollBridge();
+ }
+ });
+ // Keep Chrome's native initialization, tab ownership, compositor, and sandbox intact.
+ android.view.ViewGroup container = findViewById(android.R.id.content);
+ android.view.View content = container.getChildAt(0);
+ // Chrome's own control_container view is left inflated and owned by ToolbarManager
+ // (removing it entirely would require gutting ToolbarManager's non-null assumptions
+ // across RootUiCoordinator). It is kept genuinely invisible via
+ // BrowserControlsState.HIDDEN, forced above, which Chrome's existing hide-on-scroll
+ // machinery implements as a full off-screen translate of the toolbar view, robust
+ // against ToolbarManager re-asserting VISIBLE later.
+ getBrowserControlsManager().setTopControlsHeight(0, 0);
+ getBrowserControlsManager().setBottomControlsHeight(0, 0);
+ com.mica.browser.ChromiumMicaHost.attach(this, content,
+ new com.mica.browser.browser.ChromiumPort() {
+ @Override public String url() {
+ Tab tab = getActivityTab();
+ return tab == null ? "" : tab.getUrl().getSpec();
+ }
+ @Override public String title() {
+ Tab tab = getActivityTab();
+ return tab == null ? "Mica" : tab.getTitle();
+ }
+ @Override public boolean loading() {
+ Tab tab = getActivityTab();
+ return tab != null && tab.isLoading();
+ }
+ @Override public boolean canGoBack() {
+ Tab tab = getActivityTab();
+ return tab != null && tab.canGoBack();
+ }
+ @Override public void navigate(String url) {
+ Tab tab = getActivityTab();
+ if (tab != null) tab.loadUrl(new org.chromium.content_public.browser.LoadUrlParams(url));
+ }
+ @Override public void back() {
+ Tab tab = getActivityTab();
+ if (tab != null && tab.canGoBack()) tab.goBack();
+ }
+ @Override public void reload() {
+ Tab tab = getActivityTab();
+ if (tab != null) tab.reload();
+ }
+ @Override public void stop() {
+ Tab tab = getActivityTab();
+ if (tab != null && tab.getWebContents() != null) tab.getWebContents().stop();
+ }
+ @Override
+ public void setScrollListener(
+ kotlin.jvm.functions.Function2 listener) {
+ mMicaScrollCallback = listener;
+ updateMicaScrollBridge();
+ }
+ });
+ // Start on an engine-rendered page instead of Chrome's native new-tab UI.
+ if (getActivityTab().getUrl().getSpec().startsWith("chrome://newtab")) {
+ getActivityTab().loadUrl(new org.chromium.content_public.browser.LoadUrlParams("about:blank"));
+ }
+ }
+
}
diff --git a/chrome/browser/browser_controls/android/java/src/org/chromium/chrome/browser/browser_controls/BrowserStateBrowserControlsVisibilityDelegate.java b/chrome/browser/browser_controls/android/java/src/org/chromium/chrome/browser/browser_controls/BrowserStateBrowserControlsVisibilityDelegate.java
index df0b45aef0334..1d95996dad142 100644
--- a/chrome/browser/browser_controls/android/java/src/org/chromium/chrome/browser/browser_controls/BrowserStateBrowserControlsVisibilityDelegate.java
+++ b/chrome/browser/browser_controls/android/java/src/org/chromium/chrome/browser/browser_controls/BrowserStateBrowserControlsVisibilityDelegate.java
@@ -39,6 +39,16 @@ public class BrowserStateBrowserControlsVisibilityDelegate extends BrowserContro
/** Predicate that tells if we're in persistent fullscreen mode. */
private final NonNullObservableSupplier mPersistentFullscreenMode;
+ /**
+ * Embedder-level override (e.g. Mica replacing Chrome's own browser chrome) that forces the
+ * controls hidden unconditionally, taking precedence over any showControlsPersistent()
+ * token. Unlike a one-off View.setVisibility(GONE) call on the control container, this is
+ * consulted every time {@link #calculateVisibilityConstraints()} recomputes (tab switch,
+ * navigation, load state changes, scroll), so it cannot be silently reverted by ToolbarManager
+ * or any other component that shares ownership of the control container view.
+ */
+ private boolean mForceHidden;
+
private long mCurrentShowingStartTime;
/**
@@ -111,8 +121,24 @@ public class BrowserStateBrowserControlsVisibilityDelegate extends BrowserContro
mTokenHolder.releaseToken(token);
}
+ /**
+ * Forces the browser controls (top and bottom toolbars) to remain hidden regardless of any
+ * showControlsPersistent() token, scroll state, or tab/navigation changes. Intended for an
+ * embedder (Mica) that replaces Chrome's browser chrome entirely and must guarantee Chrome's
+ * own toolbar never becomes visible again, on any tab or navigation.
+ *
+ * @param forceHidden Whether to force the controls hidden.
+ */
+ public void setForceHidden(boolean forceHidden) {
+ if (mForceHidden == forceHidden) return;
+ mForceHidden = forceHidden;
+ updateVisibilityConstraints();
+ }
+
private @BrowserControlsState int calculateVisibilityConstraints() {
- if (mPersistentFullscreenMode.get()) {
+ if (mForceHidden) {
+ return BrowserControlsState.HIDDEN;
+ } else if (mPersistentFullscreenMode.get()) {
return BrowserControlsState.HIDDEN;
} else if (ChromeFeatureList.sToolbarScrollAblation.isEnabled()
|| (mTokenHolder.hasTokens() && !sDisableOverridesForTesting)) {
diff --git a/third_party/androidx/customizations.gni b/third_party/androidx/customizations.gni
index 722779334cc5c..27c9a4fc22905 100644
--- a/third_party/androidx/customizations.gni
+++ b/third_party/androidx/customizations.gni
@@ -21,6 +21,13 @@ template("_androidx_prebuilt") {
forward_variables_from(invoker, "*", [ "target_type" ])
}
+ if (defined(visibility)) {
+ # //mica:* wraps a handful of these as prebuilt AARs for the Mica browser shell.
+ # //chrome/android:* is chrome_java itself, which depends directly on the compose
+ # UI android resources target (androidx_compose_ui_ui_android_java) alongside //mica:ui_java.
+ visibility += [ "//mica:*", "//chrome/android:*" ]
+ }
+
if (target_name == "androidx_annotation_annotation_java") {
# Ensure this dep is the suggested one when targets are missing it.
preferred_dep = true