Add dynamic thresholds for taskbar based on screen size.

Bug: 274467454
Test: Manually test that each threshold is as expected
Change-Id: Ifa66cfb78f544bb4d14391e70badc92589d47a26

quickstep/src/com/android/launcher3/taskbar/TaskbarThresholdUtils.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2023 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.launcher3.taskbar;
+
+import static com.android.launcher3.Utilities.dpToPx;
+import static com.android.launcher3.Utilities.dpiFromPx;
+
+import android.content.res.Resources;
+import android.util.DisplayMetrics;
+
+import androidx.core.content.res.ResourcesCompat;
+
+import com.android.launcher3.DeviceProfile;
+import com.android.launcher3.R;
+import com.android.launcher3.config.FeatureFlags;
+
+/**
+ * Utility class that contains the different taskbar thresholds logic.
+ */
+public class TaskbarThresholdUtils {
+
+    // We divide the screen into this many parts, and use the result to scale the thresholds to
+    // any size device. Note that this value was calculated arbitrarily by using two tablet devices
+    // as data points.
+    private static final float SCREEN_UNITS = 1 / 80f;
+
+    private static int getThreshold(Resources r, DeviceProfile dp, int thresholdDimen,
+            int multiplierDimen) {
+        if (!FeatureFlags.ENABLE_DYNAMIC_TASKBAR_THRESHOLDS.get()) {
+            return r.getDimensionPixelSize(thresholdDimen);
+        }
+
+        float landscapeScreenHeight = dp.isLandscape ? dp.heightPx : dp.widthPx;
+        float screenPart = (landscapeScreenHeight * SCREEN_UNITS);
+        float defaultDp = dpiFromPx(screenPart, DisplayMetrics.DENSITY_DEVICE_STABLE);
+        float thisDp = dpToPx(defaultDp);
+        float multiplier = ResourcesCompat.getFloat(r, multiplierDimen);
+        float value = (thisDp) * multiplier;
+
+        return Math.round(value);
+    }
+
+    /**
+     * Returns the threshold that determines if we should show taskbar.
+     */
+    public static int getFromNavThreshold(Resources r, DeviceProfile dp) {
+        return getThreshold(r, dp, R.dimen.taskbar_from_nav_threshold,
+                R.dimen.taskbar_nav_threshold_mult);
+    }
+
+    /**
+     * Returns the threshold that we start moving the app window.
+     */
+    public static int getAppWindowThreshold(Resources r, DeviceProfile dp) {
+        return getThreshold(r, dp, R.dimen.taskbar_app_window_threshold,
+                R.dimen.taskbar_app_window_threshold_mult);
+    }
+
+    /**
+     * Returns the threshold for whether we land in home or overview.
+     */
+    public static int getHomeOverviewThreshold(Resources r, DeviceProfile dp) {
+        return getThreshold(r, dp, R.dimen.taskbar_home_overview_threshold,
+                R.dimen.taskbar_home_overview_threshold_mult);
+    }
+
+    /**
+     * Returns the threshold that we use to allow swipe to catch up to finger.
+     */
+    public static int getCatchUpThreshold(Resources r, DeviceProfile dp) {
+        return getThreshold(r, dp, R.dimen.taskbar_catch_up_threshold,
+                R.dimen.taskbar_catch_up_threshold_mult);
+    }
+}