hi,粉丝朋友们！
上一节已经对车载的多屏互动进行了相关的技术方案介绍，以及相关的核心方法
moveRootTaskToDisplay的讲解和使用。
具体可以参考链接：https://blog.csdn.net/learnframework/article/details/130461689
本节就来进行代码实战
1、方案设计
要实现双屏互动，主要就只需要两个步骤：
1、手指动作识别
2、识别动作后触发寻找display，获取顶部task，触发moveTask操作
2、手势动作识别部分
触发手势设计：因为模拟器实现条件有限，所以这里采用是双指向右移动一定距离触发。
首先要进行对手指全局移动的监听，针对多个手指的触摸移动动作要进行识别。
代码实现：
单独建立一个PointerEventListener的实现子类叫做DoubleScreenMovePointerEventListener，在这里面的onPointerEvent方法即可以实现对应的触摸动作识别，这里实现是双指同时滑动触摸方式：
diff --git a/services/core/java/com/android/server/wm/DoubleScreenMovePointerEventListener.java b/services/core/java/com/android/server/wm/DoubleScreenMovePointerEventListener.java
new file mode 100644
index 000000000000..f9c765476d19
--- /dev/null
+++ b/services/core/java/com/android/server/wm/DoubleScreenMovePointerEventListener.java
@@ -0,0 +1,62 @@
+package com.android.server.wm;
+
+import android.view.MotionEvent;
+import android.view.WindowManagerPolicyConstants;
+
+public class DoubleScreenMovePointerEventListener implements WindowManagerPolicyConstants.PointerEventListener {
+ boolean shouldBeginMove = false;
+ int mPoint0FirstX = 0;
+ int mPoint1FirstX = 0;
+
+ int mPoint0LastX = 0;
+ int mPoint1LastX = 0;
+ int START_GAP = 20;//动作触发阈值，最少移动为20个像素才可以
+ private final WindowManagerService mService;
+
+ public DoubleScreenMovePointerEventListener(WindowManagerService mService, DisplayContent mDisplayContent) {
+ this.mService = mService;
+ this.mDisplayContent = mDisplayContent;
+ }
+
+ private final DisplayContent mDisplayContent;
+
+ @Override
+ public void onPointerEvent(MotionEvent motionEvent) {
+ android.util.Log.i("DoubleScreenTouch","DoubleScreenMovePointerEventListener onPointerEvent motionEvent = "+motionEvent);
+ switch (motionEvent.getActionMasked()) {
+ case MotionEvent.ACTION_DOWN:
+ case MotionEvent.ACTION_POINTER_DOWN:
+ if (motionEvent.getPointerCount() > 2) {
+ shouldBeginMove = false;
+ android.util.Log.i("DoubleScreen","DoubleScreenMovePointerEventListener motionEvent.getPointerCount() > 2 end DoubleScreenMove ");
+ }
+ if (motionEvent.getPointerCount() == 2) {
+ if (mPoint0FirstX == 0 && mPoint1FirstX == 0) {
+ mPoint0FirstX = (int)motionEvent.getX(0);
+ mPoint1FirstX = (int)motionEvent.getX(1);
+ }
+ }
+ break;
+ case MotionEvent.ACTION_MOVE:
+ if (motionEvent.getPointerCount() == 2) {
+ if (!shouldBeginMove && motionEvent.getX(0) - mPoint0FirstX > START_GAP &&
+ motionEvent.getX(1) - mPoint1FirstX > START_GAP) {
//识别了双指动作达到触发task移动条件，则调用对应mDisplayContent.doTestMoveTaskToOtherDisplay方法
+ android.util.Log.i("DoubleScreen","DoubleScreenMovePointerEventListener start DoubleScreenMove ");
+ shouldBeginMove = true;
+ mDisplayContent.doTestMoveTaskToOtherDisplay();
+ }
+
+ mPoint0LastX = (int)motionEvent.getX(0);
+ mPoint1LastX = (int)motionEvent.getX(1);
+ }
+ break;
+ case MotionEvent.ACTION_POINTER_UP:
+ case MotionEvent.ACTION_UP:
+ shouldBeginMove = false;
+ mPoint0FirstX = mPoint1FirstX =0;
+ android.util.Log.i("DoubleScreen","DoubleScreenMovePointerEventListener ACTION_UP end DoubleScreenMove ");
+ break;
+ }
+ }
+
+}
同时不要忘记需要把这个PointEventListener让displaycontent注册监听：
@@ -1063,7 +1085,9 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
// 1. All physical displays (multi-display).
// 2. VirtualDisplays on VR, AA (and everything else).
mTapDetector = new TaskTapPointerEventListener(mWmService, this);//需要传递WMS和DisplayContent方便调用
+ mDoubleScreenMoveListener = new DoubleScreenMovePointerEventListener(mWmService, this);
registerPointerEventListener(mTapDetector);
+ registerPointerEventListener(mDoubleScreenMoveListener);
registerPointerEventListener(mWmService.mMousePositionTracker);
if (mWmService.mAtmService.getRecentTasks() != null) {
registerPointerEventListener(
3、寻找当前Display的Task，移动到目标display
触摸动作识别后会调用DisplayContent的doTestMoveTaskToOtherDisplay方法来完成剩下的业务：
1、获取要移动到的目标display对象
2、获取当前display要移动的Task对象
3、调用RootWindowContainer的moveRootTaskToDisplay方法来实现
+//add by doublescreenmove
+ public void doTestMoveTaskToOtherDisplay() {
+ DisplayContent otherDisplay = null;
+ if (mRootWindowContainer.getChildCount() == 2) {
//检测是不是双屏
+ otherDisplay = (mRootWindowContainer.getChildAt(0) == this) ? mRootWindowContainer.getChildAt(1):mRootWindowContainer.getChildAt(0);//获取另一个屏幕的DisplayContent
+ }
+ if (otherDisplay!= this && otherDisplay!= null) {
+ int rootTaskId = 0;
+ try {
+ Task rootTask = getTopRootTask();//获取当前display的顶部Task
+ if (rootTask.isActivityTypeHome()) {
//home类型的task不支持移动
+ android.util.Log.i("DoubleScreen","doTestMoveTaskToOtherDisplay isActivityTypeHome");
+ return;
+ }
+ rootTaskId =rootTask.mTaskId;
+ mRootWindowContainer.moveRootTaskToDisplay(rootTaskId,otherDisplay.mDisplayId,true);//把task移动到另一屏
+ }catch (Exception e) {
+ android.util.Log.i("DoubleScreen","doTestMoveTaskToOtherDisplay Exception",e);
+ }
+ }
+ }
+ //end by doublescreenmove
成果展示：
模拟器调试要点：
这个部分请关注bibili的 “千里马学框架”视频
https://www.bilibili.com/video/BV1Tv4y1J7eb
相关源码及资料
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