Android系统添加自定义鼠标样式如何通过按键切换
一、APP通过View修改鼠标样式
app view上修改鼠标样式比较简单，通过hover event 获取鼠标坐标并使用如下方法修改为自定义图片：
getWindow().getDecorView().setPointerIcon(PointerIcon.load(getResources(), R.drawable.pointer_spot_touch_icon));
imageView = (ImageView) findViewById(R.id.image_view); imageView.setOnHoverListener(new View.OnHoverListener() { @SuppressLint({"SetTextI18n", "ResourceType"}) @Override public boolean onHover(View v, MotionEvent event) { int what = event.getAction(); textX.setText("X : " + event.getX()); textY.setText("Y : " + event.getY()); switch(what){ case MotionEvent.ACTION_HOVER_ENTER: //鼠标进入view Log.i(TAG, "bottom ACTION_HOVER_ENTER..."); mOrgPI = getWindow().getDecorView().getPointerIcon(); getWindow().getDecorView().setPointerIcon(PointerIcon.load(getResources(), R.drawable.pointer_spot_touch_icon)); break; case MotionEvent.ACTION_HOVER_MOVE: //鼠标在view上 Log.i(TAG, "bottom ACTION_HOVER_MOVE..."); break; case MotionEvent.ACTION_HOVER_EXIT: //鼠标离开view Log.i(TAG, "bottom ACTION_HOVER_EXIT..."); getWindow().getDecorView().setPointerIcon(mOrgPI); break; } return false; } }); }
其中pointer_spot_touch_icon.xml 需要声明为pointer-icon ：
但是app修改鼠标样式的view关闭后，鼠标样式会恢复成默认的黑箭头，因此不依赖APP去动态切换鼠标样式需要在framework层修改系统源码实现。
二、framework层添加自定义鼠标样式并通过按键切换
（1）添加自定义样式资源
系统图标资源在 frameworks/base/core/res/res/drawable-mdpi/ 目录，其中pointer_arrow.png、pointer_arrow_large.png 是系统默认的黑色箭头，
pointer_arrow_red_dot.png、pointer_arrow_red_dot_large.png 是自己添加的红点样式图片：
然后在 frameworks/base/core/res/res/drawable/ 目录添加对应的xml:
pointer_arrow_red_dot_icon.xml
pointer_arrow_red_dot_large_icon.xml
修改 frameworks/base/core/res/res/values/styles.xml 添加资源配置，注意名字的匹配！
修改frameworks/base/core/res/res/values/attrs.xml 引用资源：
（2）Java 层获取资源
修改 frameworks/base/core/java/android/view/PointerIcon.java ，添加如下定义：
在 getSystemIconTypeIndex(int type) 函数中返回之前配置的资源：
（3）c++层添加对应的id并加载资源
修改 frameworks/base/core/jni/android_view_PointerIcon.h
* Pointer icon styles. * Must match the definition in android.view.PointerIcon. */enum { POINTER_ICON_STYLE_CUSTOM = -1, POINTER_ICON_STYLE_NULL = 0, POINTER_ICON_STYLE_ARROW = 1000, POINTER_ICON_STYLE_CONTEXT_MENU = 1001, POINTER_ICON_STYLE_HAND = 1002, POINTER_ICON_STYLE_HELP = 1003, POINTER_ICON_STYLE_WAIT = 1004, POINTER_ICON_STYLE_CELL = 1006, POINTER_ICON_STYLE_CROSSHAIR = 1007, POINTER_ICON_STYLE_TEXT = 1008, POINTER_ICON_STYLE_VERTICAL_TEXT = 1009, POINTER_ICON_STYLE_ALIAS = 1010, POINTER_ICON_STYLE_COPY = 1011, POINTER_ICON_STYLE_NO_DROP = 1012, POINTER_ICON_STYLE_ALL_SCROLL = 1013, POINTER_ICON_STYLE_HORIZONTAL_DOUBLE_ARROW = 1014, POINTER_ICON_STYLE_VERTICAL_DOUBLE_ARROW = 1015, POINTER_ICON_STYLE_TOP_RIGHT_DOUBLE_ARROW = 1016, POINTER_ICON_STYLE_TOP_LEFT_DOUBLE_ARROW = 1017, POINTER_ICON_STYLE_ZOOM_IN = 1018, POINTER_ICON_STYLE_ZOOM_OUT = 1019, POINTER_ICON_STYLE_GRAB = 1020, POINTER_ICON_STYLE_GRABBING = 1021, POINTER_ICON_STYLE_SPOT_HOVER = 2000, POINTER_ICON_STYLE_SPOT_TOUCH = 2001, POINTER_ICON_STYLE_SPOT_ANCHOR = 2002, POINTER_ICON_STYLE_REDDOT = 10001, //增加自定义样式的枚举定义，与上面 PointerIcon.java 中的变量对应};
修改frameworks/base/services/core/jni/com_android_server_input_InputManagerService.cpp ，加载到自定义枚举变量对应的图片资源：
void NativeInputManager::loadAdditionalMouseResources(std::map