/*
 * 显示刷新率开关控制函数
 *     0 = 关闭
 *     1 = 开启  
 *     2 = 查询当前状态（返回 true/false）
 *     3 = 切换（打开→关 / 关→开）
 */
function showRefreshRate(mode) {
    sf = android.os.ServiceManager.getService("SurfaceFlinger");

    function call(flag, needReply) {
        data = android.os.Parcel.obtain();
        reply = needReply ? android.os.Parcel.obtain() : null;
        data.writeInterfaceToken("android.ui.ISurfaceComposer");
        data.writeInt(flag);
        sf.transact(1034, data, reply, 0);
        return reply;
    }

    if (mode == 3) {
        current = call(2, true).readBoolean();
        call(current ? 0 : 1, false);
        return !current;
    }

    // mode: 0=关 1=开 2=查
    if (mode == 2) {
        return call(2, true).readBoolean();
    } else {
        call(mode, false);
        return mode == 1;
    }
}

// 切换显示屏刷新率显示开关
showRefreshRate(3);

#MVEL表达式 #Javascript