Add ability to register listeners with SplitState (a72264cc) · Commits · e / os / android_frameworks_base

libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitState.java

+46 −0

Original line number	Diff line number	Diff line
		@@ -23,10 +23,13 @@ import static com.android.wm.shell.shared.split.SplitScreenConstants.SNAP_TO_3_1
		import static com.android.wm.shell.shared.split.SplitScreenConstants.SNAP_TO_3_45_45_10;
		import static com.android.wm.shell.shared.split.SplitScreenConstants.SplitScreenState;

		import android.annotation.NonNull;
		import android.graphics.Rect;
		import android.graphics.RectF;

		import java.util.HashSet;
		import java.util.List;
		import java.util.Set;

		/**
		* A class that manages the "state" of split screen. See {@link SplitScreenState} for definitions.
		@@ -34,10 +37,13 @@ import java.util.List;
		public class SplitState {
		private @SplitScreenState int mState = NOT_IN_SPLIT;
		private SplitSpec mSplitSpec;
		private final Set<SplitStateChangeListener> mListeners = new HashSet<>();


		/** Updates the current state of split screen on this device. */
		public void set(@SplitScreenState int newState) {
		mState = newState;
		notifyListeners();
		}

		/** Reports the current state of split screen on this device. */
		@@ -74,4 +80,44 @@ public class SplitState {
		\|\| mState == SNAP_TO_3_10_45_45
		\|\| mState == SNAP_TO_3_45_45_10;
		}

		/**
		* Registers a listener to receive notifications when the split state changes.
		* Multiple instances of the same listener will not be tolerated. Don't be weird.
		*
		* @param listener The listener to register.
		*/
		public void registerSplitStateChangeListener(@NonNull SplitStateChangeListener listener) {
		mListeners.add(listener);
		}

		/**
		* Unregisters a listener, so it no longer receives notifications.
		*
		* @param listener The listener to unregister.
		*/
		public void unregisterSplitStateChangeListener(@NonNull SplitStateChangeListener listener) {
		mListeners.remove(listener);
		}

		/**
		* Notifies all registered listeners of the current split state.
		*/
		private void notifyListeners() {
		for (SplitStateChangeListener listener : mListeners) {
		listener.onSplitStateChanged(mState);
		}
		}

		/**
		* An interface for listeners that want to be notified of split state changes.
		*/
		public interface SplitStateChangeListener {
		/**
		* Called when the split state of the splitter changes.
		*
		* @param splitState The new split state.
		*/
		void onSplitStateChanged(@SplitScreenState int splitState);
		}
		}

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/splitscreen/SplitStateTests.kt

0 → 100644

+113 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2025 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.wm.shell.splitscreen

		import androidx.test.filters.SmallTest
		import androidx.test.runner.AndroidJUnit4
		import com.android.wm.shell.common.split.SplitState
		import com.android.wm.shell.shared.split.SplitScreenConstants
		import com.android.wm.shell.shared.split.SplitScreenConstants.NOT_IN_SPLIT
		import com.android.wm.shell.shared.split.SplitScreenConstants.SNAP_TO_2_50_50
		import com.android.wm.shell.shared.split.SplitScreenConstants.SNAP_TO_3_10_45_45
		import org.junit.Assert.assertEquals
		import org.junit.Before
		import org.junit.Test
		import org.junit.runner.RunWith

		@SmallTest
		@RunWith(AndroidJUnit4::class)
		class SplitStateTests {

		val DEFAULT_VALUE = -4

		private lateinit var splitter: SplitState
		private lateinit var listener1: TestListener
		private lateinit var listener2: TestListener

		@Before
		fun setUp() {
		splitter = SplitState()
		listener1 = TestListener()
		listener2 = TestListener()
		}

		@Test
		fun testRegisterAndNotify() {
		splitter.registerSplitStateChangeListener(listener1)
		splitter.set(SNAP_TO_2_50_50)
		assertEquals(SNAP_TO_2_50_50, listener1.lastState)

		splitter.set(SNAP_TO_3_10_45_45)
		assertEquals(SNAP_TO_3_10_45_45, listener1.lastState)
		}

		@Test
		fun testMultipleListeners() {
		splitter.registerSplitStateChangeListener(listener1)
		splitter.registerSplitStateChangeListener(listener2)

		splitter.set(SNAP_TO_3_10_45_45)
		assertEquals(SNAP_TO_3_10_45_45, listener1.lastState)
		assertEquals(SNAP_TO_3_10_45_45, listener2.lastState)
		}

		@Test
		fun testUnregisterListener() {
		splitter.registerSplitStateChangeListener(listener1)
		splitter.registerSplitStateChangeListener(listener2)
		splitter.unregisterSplitStateChangeListener(listener1)

		splitter.set(SNAP_TO_2_50_50)
		assertEquals(DEFAULT_VALUE, listener1.lastState) // Listener 1 should not be notified
		assertEquals(SNAP_TO_2_50_50, listener2.lastState)
		}

		@Test
		fun testNoListeners() {
		splitter.set(SNAP_TO_2_50_50)
		// No listeners registered, so no exceptions should be thrown.
		}

		@Test
		fun testRegisterSameListenerMultipleTimes() {
		splitter.registerSplitStateChangeListener(listener1)
		splitter.registerSplitStateChangeListener(listener1)

		splitter.set(SNAP_TO_2_50_50)
		assertEquals(SNAP_TO_2_50_50, listener1.lastState)
		assertEquals(1, listener1.callCount) // should only be called once.
		}

		@Test
		fun testExit() {
		splitter.registerSplitStateChangeListener(listener1)
		splitter.exit()

		assertEquals(NOT_IN_SPLIT, listener1.lastState)
		}

		// Helper class for testing
		inner class TestListener : SplitState.SplitStateChangeListener {
		var lastState = DEFAULT_VALUE
		var callCount = 0

		override fun onSplitStateChanged(@SplitScreenConstants.SplitScreenState splitState: Int) {
		this.lastState = splitState
		callCount++
		}
		}
		}
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