Android系统全局触摸事件监听
Android触摸全局监听指的是调用监听后在任何界面都能获取到触摸事件。
要实现这个功能必须要修改源码添加新的接口,因为系统默认是不暴露这个方法的。
监听系统全局触摸事件的类和相关代码:
frameworks\base\services\core\java\com\android\server\wm\WindowManagerService.java
@Override
public void registerPointerEventListener(PointerEventListener listener, int displayId) {
Slog.i(TAG, "registerPointerEventListener PointerEventListener = " + listener);
synchronized (mGlobalLock) {
final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
if (displayContent != null) {
displayContent.registerPointerEventListener(listener);
}
}
}
@Override
public void unregisterPointerEventListener(PointerEventListener listener, int displayId) {
synchronized (mGlobalLock) {
final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
if (displayContent != null) {
displayContent.unregisterPointerEventListener(listener);
}
}
}
第一个参数:是中PointerEventListener接口,
里面有MotionEvent对象含有点击事件,比如DOWN、UP、MOVING等其他信息。
package android.view;
public interface WindowManagerPolicyConstants {
interface PointerEventListener {
void onPointerEvent(MotionEvent motionEvent);
}
}
第二个参数,屏幕id,正常用0 ,表示主屏幕id。有些设备有投屏或者第二屏才需要关注这个。
下面介绍如何注册这个服务
1、绑定这个系统服务,这个方法行不通
因为这个服务的aidl接口IWindowManager,并没有暴露这个方法
registerPointerEventListener方法定义在另一个内部接口 WindowManagerFuncs 中
public interface WindowManagerPolicy extends WindowManagerPolicyConstants {
public interface WindowManagerFuncs {
/** Register a system listener for touch events */
void registerPointerEventListener(PointerEventListener listener, int displayId);
/** Unregister a system listener for touch events */
void unregisterPointerEventListener(PointerEventListener listener, int displayId);
}
}
2、获取WindowManagerFuncs对象,该对象获取的方式在源码中有多种
参考:
frameworks\base\services\core\java\com\android\server\policy\PhoneWindowManager.java
public PhoneWindowManager extends AbsPhoneWindowManager implements WindowManagerPolicy, IHwPhoneWindowManagerInner{
public WindowManagerFuncs getWindowManagerFuncs(){
return mWindowManagerFuncs;
}
}
WindowManagerFuncs在源码中是可以直接new的,使用如下:
PhoneWindowManager phoneWindowManager = new PhoneWindowManager();
WindowManagerFuncs windowManagerFuncs = phoneWindowManager.getWindowManagerFuncs();
windowManagerFuncsEx.registerPointerEventListener(listener, Display.DEFAULT_DISPLAY);
3、在华为Emui源码添加aidl回调
WindowManagerEx有通道直接发送数据到WindowManagerService并可以进行数据监听
(1)添加aidl接口
vendor\huawei\Emui\frameworks\hwCommInterface\base\core\java\com\huawei\android\app\IHwPointEventCallback.aidl
package com.huawei.android.app;
import android.view.MotionEvent;
oneway interface IHwPointEventCallback {
void onPointerEvent(in MotionEvent motionEvent);
}
(2)WindowManagerEx的修改
vendor\huawei\Emui\frameworks\hwext\hwext\framework\src\com\huawei\android\app\WindowManagerEx.java
private final int TRANSACTION_SET_POINTER_EVENT_LISTENER = android.os.IBinder.FIRST_CALL_TRANSACTION + 2100;
//给WindowManagerService传递监听对象
public static void setPointerEventListener(IHwPointEventCallback listener) {
Log.i(LOG_TAG, "setPointerEventListener listener = " + listener);
IBinder windowManagerBinder = WindowManagerGlobal.getWindowManagerService().asBinder();
if (windowManagerBinder != null) {
Parcel data = Parcel.obtain();
Parcel reply = Parcel.obtain();
try {
data.writeInterfaceToken("android.view.IWindowManager");
//传递aidl监听对象
data.writeStrongBinder(listener != null ? listener.asBinder() : null);
//发送
windowManagerBinder.transact(TRANSACTION_SET_POINTER_EVENT_LISTENER, data, reply, 0);
} catch (RemoteException e){
Log.e(LOG_TAG, "setPointerEventListener exception is " + e.getMessage());
} finally {
data.recycle();
reply.recycle();
}
} else {
Log.w(LOG_TAG, "setPointerEventListener windowManagerBinder is null");
}
}
(3)在WindowManagerService中接收数据并做实际监听
基于尽量不修改源码的理念,Emui中有WindowManagerService的子类HwWindowManagerService,在子类中修改代码即可。
vendor\huawei\Emui\frameworks\base\services\java\huawei\com\android\server\wm\HwWindowManagerService.java
HwWindowManagerService extends WindowManagerService
private final int TRANSACTION_SET_POINTER_EVENT_LISTENER = android.os.IBinder.FIRST_CALL_TRANSACTION + 2100;
private IHwPointEventCallback mIHwPointEventCallback = null;
//接收WindowManagerEx传递过来的数据
public boolean onTransact(int code, Parcel data, Parcel reply, int flags)
throws RemoteException {
switch (code) {
case TRANSACTION_SET_POINTER_EVENT_LISTENER:
data.enforceInterface("android.view.IWindowManager");
IHwPointEventCallback observer = IHwPointEventCallback.Stub.asInterface(data.readStrongBinder());
setPointerEventListener(observer);
reply.writeNoException();
return true;
}
}
//在Service中创建唯一的监听对象
private PointerEventListener mPointerEventListener = new PointerEventListener() {
@Override
public void onPointerEvent(MotionEvent motionEvent) {
if(mIHwPointEventCallback != null) {
try {
mIHwPointEventCallback.onPointerEvent(motionEvent);
} catch (RemoteException e) {
Slog.e(TAG, "mIHwPointEventCallback error = " + e.getMessage());
}
}
}
};
//添加设置触摸监听方法
private void setPointerEventListener(IHwPointEventCallback listener) {
Slog.i(TAG, "setPointerEventListener PointerEventListener = " + listener);
int uid = Binder.getCallingUid();
if(uid != Process.SYSTEM_UID){
Slog.e(TAG, "setPointerEventListener uid must be "+ Process.SYSTEM_UID +",but now uid = " + uid);
return;
}
mIHwPointEventCallback = listener;
if(listener != null) {
//实际调到父类的注册触摸事件的方法
registerPointerEventListener(mPointerEventListener, Display.DEFAULT_DISPLAY);
}
else {
//实际调到父类的反注册触摸事件的方法
unregisterPointerEventListener(mPointerEventListener, Display.DEFAULT_DISPLAY);
}
}
方法3可以实现在普通app中监听到系统的全局触摸事件,
因为app可以依赖Emui的emui_addons.jar,
调用到里面的部分类,比如WindowManagerEx,就可以监听全局触摸事件。
其他系统环境可以根据实际情况参考上面的实现。