CN110647300A - Method for using printer by android platform QT program - Google Patents

Method for using printer by android platform QT program Download PDF

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Publication number
CN110647300A
CN110647300A CN201910821346.0A CN201910821346A CN110647300A CN 110647300 A CN110647300 A CN 110647300A CN 201910821346 A CN201910821346 A CN 201910821346A CN 110647300 A CN110647300 A CN 110647300A
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printer
android
printing
program
document
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张德星
其他发明人请求不公开姓名
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Shenzhen Tekang Bioengineering Co
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Shenzhen Tekang Bioengineering Co
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/12—Digital output to print unit, e.g. line printer, chain printer
    • G06F3/1201—Dedicated interfaces to print systems
    • G06F3/1202—Dedicated interfaces to print systems specifically adapted to achieve a particular effect
    • G06F3/121—Facilitating exception or error detection and recovery, e.g. fault, media or consumables depleted
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/14—Error detection or correction of the data by redundancy in operation
    • G06F11/1402—Saving, restoring, recovering or retrying
    • G06F11/1446—Point-in-time backing up or restoration of persistent data
    • G06F11/1448—Management of the data involved in backup or backup restore
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F21/10—Protecting distributed programs or content, e.g. vending or licensing of copyrighted material ; Digital rights management [DRM]
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F21/60—Protecting data
    • G06F21/62—Protecting access to data via a platform, e.g. using keys or access control rules
    • G06F21/6218—Protecting access to data via a platform, e.g. using keys or access control rules to a system of files or objects, e.g. local or distributed file system or database
    • G06F21/6245—Protecting personal data, e.g. for financial or medical purposes
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/12—Digital output to print unit, e.g. line printer, chain printer
    • G06F3/1201—Dedicated interfaces to print systems
    • G06F3/1202—Dedicated interfaces to print systems specifically adapted to achieve a particular effect
    • G06F3/1222—Increasing security of the print job
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/12—Digital output to print unit, e.g. line printer, chain printer
    • G06F3/1201—Dedicated interfaces to print systems
    • G06F3/1223—Dedicated interfaces to print systems specifically adapted to use a particular technique
    • G06F3/1224—Client or server resources management
    • G06F3/1228—Printing driverless or using generic drivers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/12—Digital output to print unit, e.g. line printer, chain printer
    • G06F3/1201—Dedicated interfaces to print systems
    • G06F3/1223—Dedicated interfaces to print systems specifically adapted to use a particular technique
    • G06F3/1237—Print job management
    • G06F3/1238—Secure printing, e.g. user identification, user rights for device usage, unallowed content, blanking portions or fields of a page, releasing held jobs
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F8/00—Arrangements for software engineering
    • G06F8/70—Software maintenance or management
    • G06F8/76—Adapting program code to run in a different environment; Porting
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F9/00—Arrangements for program control, e.g. control units
    • G06F9/06—Arrangements for program control, e.g. control units using stored programs, i.e. using an internal store of processing equipment to receive or retain programs
    • G06F9/44—Arrangements for executing specific programs
    • G06F9/4401—Bootstrapping
    • G06F9/4411—Configuring for operating with peripheral devices; Loading of device drivers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2221/00—Indexing scheme relating to security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F2221/21—Indexing scheme relating to G06F21/00 and subgroups addressing additional information or applications relating to security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F2221/2141—Access rights, e.g. capability lists, access control lists, access tables, access matrices

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Abstract

A method for using a printer by an Android platform QT program comprises the steps of integrating a Qt for Android environment on an Android device, then correctly connecting the printer, installing a printing plug-in provided by a printer official, simultaneously realizing communication between C/C + + and JAVA language by adopting a JNI technology, solving the problem that the Qt program in the prior art is difficult to conveniently use the printer due to the programming language, optimizing the JNI technology, ensuring high efficiency and stability when the JNI interface executes JAVA codes by calling abnormity detection and cache region establishment during the JAVA codes, providing a backup function of a printing service object for a user, meeting repeated printing and historical backup requirements of the user as far as possible while protecting the privacy of the user, successfully realizing printing tasks by a Qt application program printing scheme by using different printer models or types, reducing development difficulty, and completely providing printer models suitable for the official plug-in, thereby also improving the applicability of the design.

Description

Method for using printer by android platform QT program
Technical Field
The invention relates to the technical field of printers used by android platforms, in particular to a method for using a printer by using an android platform QT program.
Background
In recent years, printers have been used more and more widely and are applied to various fields and different platforms. Which is also widely used in the embedded field in demand. Such as printing quality control reports in medical devices. In the development of a standard embedded ARM-Linux + Qt system, a printer is required to be used, and the traditional method is to transplant a CUPS (Common UNIX printing system) which includes a program related to the reception of a print command at the front end, a program controlling the printer hardware at the back end, and a print driver in the middle. At present, the method is also used for realizing printing on the Qt on Android platform.
However, in the prior art, it is complicated to transplant a CUPS to an Android system, and the printer frame composition is also different according to different printer types or models, the size of the file system after transplantation may be increased a lot, the configuration and transplantation difficulties are also complicated, and the method cannot be simplified, and is difficult to use a printer in a qton Android environment in a portable manner.
Qt, as an application that can support cross-platform development, can also run on Windows, MAC OS, and Android systems, and Qt itself also provides a printer framework, but is not suitable for use on the Android system, but only in Windows and MAC OS operating systems.
Disclosure of Invention
1. Technical problem to be solved
Aiming at the problems in the prior art, the invention aims to provide a method for using a printer by an Android platform QT program, which can avoid the transplanting problem and the compatibility problem caused by using different printer types, correctly connects the printer and installs a printer plug-in after integrating a Qt for Android environment on an Android device, simultaneously adopts a JNI technology to realize the communication between C/C + + and JAVA language, solves the problem that the Qt program in the prior art cannot conveniently use the printer because of programming language, optimizes the JNI technology, ensures the high efficiency and stability when the JNI interface executes the JAVA code by detecting the abnormity and establishing a cache region when the JAVA code is called, provides the backup function of printing service objects for a user, and meets the repeated printing and historical backup requirements of the user as much as possible while protecting the privacy of the user, the invention can successfully realize the printing task by the Qt application program printing scheme by using different printer models or types, thereby reducing the development difficulty and improving the applicability.
2. Technical scheme
In order to solve the above problems, the present invention adopts the following technical solutions.
A method for using a printer by an android platform QT program comprises the following steps:
integrating a Qt for Android environment, preparing a printer with a USB or network interface, and correctly connecting an Android device;
reminding a user of installing the used printer plug-in on the Android equipment;
step three, after the printer plug-in is installed successfully, the printer plug-in is kept in an open state and waits to be called;
generating a document by the Qt application program according to the printed content, providing a printing button, calling a JNI interface to execute a JAVA code by clicking the button, using a printing function provided by an Android system under the JAVA programming environment, finally transferring the document content to a printer plug-in, and jumping to a printing interface, wherein the printing interface comprises document preview, printing parameters and the like;
step five, in the printing interface, the plug-in automatically finds the corresponding printer, clicks a printing button after selecting the printer, and finishes the printing work by the printer plug-in;
and step six, waiting for the printing end or abnormity.
Further, the integrating the Qt for Android environment in the first step includes the following operations:
operation 1: downloading and preparing Java jdk, Android sdk, Android adb, Android ndk, Android ant and Qt;
operation 2: sequentially installing and configuring java jdk, Android sdk, Android adb, Android ndk and Android ant;
operation 3: installing Qt for Android and starting a qtcreator.
And operation 4: and (4) configuring a software path and running and debugging.
And configuring a system environment to realize the operation of the Qt application program in the Android system.
Furthermore, after the printed content is generated into a document by the Qt application program in the fourth step, the document is automatically backed up into an appointed folder, so that the document can be used as a backup file for a user to use after being lost outside the source file, and the backup file can be directly called for printing when repeated printing is performed, which is convenient and fast.
Further, the folder is a hidden folder, the hidden folder has user access authority, the system automatically runs a screen locking program after three continuous times of access failures, the hidden folder can avoid mistaken deletion or other misoperation of the user, certain privacy is provided, stealing by outsiders is prevented, the access authority is also provided for safety protection even after display, and the system can judge abnormal operation to perform system screen locking protection after three continuous times of access failures.
Furthermore, the backup document has a fixed temporary storage period which is 30-60d, the backup document is deleted automatically after the period of time is expired, so that permanent storage of the backup document can be avoided from occupying a large amount of memory, meanwhile, the backup document can be basically judged as an expired document when the backup document is not called after the period of time exceeds 30-60d, the memory can be saved after deletion, and meanwhile, the program running speed can be increased.
Furthermore, when the Qt application program backups the document, a limited access link is established and only can be accessed through the link by the Qt application program, the Qt application program also provides a history calling window and displays the calling-available history document, the limited access link is provided with an extraction password, a user can conveniently search the backup document directly through the history calling window after entering a Qt application page, the link is effective after clicking and is quickly positioned to the backup document, and the document can be directly called after inputting the extraction password.
Further, the specific process in the fourth step is that by clicking a print button, a callObjectMethod is called by a Qt application program to obtain a printer service object on the Android device, a static callObjectMethod is called by the Qt application program through a JNI interface to transmit the printer service object as a parameter, and a written JAVA code is called, and the printer service object is received.
Furthermore, the written JAVA code is called to detect an exception, if the JAVA code is abnormal, the JAVA code is immediately returned and the exception is thrown, if the exception is not present, the code is continuously executed, the requested field cannot be found when the JAVA code is called, nosuchfelder occurs, if the native code is continuously running without detecting the exception, and the field ID which the native code considers to be returned is used, the program crash is caused, and the exception detection and the active throw-out are performed when the JAVA code is called, so that the possibility of the program crash can be greatly reduced.
9. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: in the fourth step, the JNI interface searches and globally caches the commonly used class, field ID and method ID, and sometimes, a large amount of work needs to be completed in the JVM to obtain the call of the field or method, because the field and method may be relayed from the super class, the JVM may traverse the class hierarchy upward to find them, and since the ID is the same for a specific class, the ID needs to be searched only once and then reused.
Further, in the sixth step, the Qt application detects the state of the printer in real time according to the return value PrintJobState of the print function, receives the returned print state value, checks the print working condition, returns to the application interface, and displays the print state for the user to view.
3. Advantageous effects
Compared with the prior art, the invention has the advantages that:
the scheme can avoid the transplanting problem and the compatibility problem caused by using different printer types, correctly connects the printer and installs the printer plug-in after integrating the Qt for Android environment on the Android equipment, simultaneously realizes the communication between C/C + + and JAVA language by adopting the JNI technology, solves the problem that the Qt program in the prior art is difficult to conveniently use the printer because of the programming language, optimizes the JNI technology, ensures the high efficiency and stability when the JNI interface executes the JAVA code by calling the abnormal detection and the establishment of the cache region when the JAVA code is called, provides the backup function of the printing service object for the user, and meets the repeated printing and historical backup requirements of the user as far as possible while protecting the privacy of the user, the invention can successfully realize the printing task by using different printer models or types through the Qt application printing scheme, the development difficulty is reduced, and the applicability is improved.
Drawings
FIG. 1 is a schematic flow chart of the present invention;
FIG. 2 is a schematic diagram of the system of the present invention;
FIG. 3 is a schematic diagram of a main process of integrating a Qt for Android environment according to the present invention;
FIG. 4 is a schematic diagram of the main process of document backup according to the present invention.
Detailed Description
The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention; it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art without any inventive work are within the scope of the present invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top/bottom", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise specifically stated or limited, the terms "mounted," "disposed," "sleeved/connected," "connected," and the like are used in a broad sense, and for example, "connected" may be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection through an intermediate medium, and a communication between two elements.
Example 1:
referring to fig. 1-2, a method for using a printer by an android platform QT program includes the following steps:
integrating a Qt for Android environment, preparing a printer with a USB or network interface, and correctly connecting an Android device;
reminding a user of installing the used printer plug-in on the Android equipment;
step three, after the printer plug-in is installed successfully, the printer plug-in is kept in an open state and waits to be called;
generating a document by the Qt application program according to the printed content, providing a printing button, calling a JNI interface to execute a JAVA code by clicking the button, using a printing function provided by an Android system under the JAVA programming environment, finally transferring the document content to a printer plug-in, and jumping to a printing interface, wherein the printing interface comprises document preview, printing parameters and the like;
the programming language of Qt is C/C + +, while the programming language of Android application layer is java, because the Android system supports a printer, in order to enable Qt to use the printer on the Android system, the solution is as follows: JNI technology (abbreviation of Java Native Interface, which can realize communication between different programming languages, and communication between C/C + + and Java language) is used for solving the problem that the Qt program in the prior art is difficult to use the printer conveniently, the realization process is simple and convenient, and the requirement of printing by a user can be met.
Step five, in the printing interface, the plug-in automatically finds the corresponding printer, clicks a printing button after selecting the printer, and finishes the printing work by the printer plug-in;
and step six, waiting for the printing end or abnormity.
Referring to fig. 3, the integrating the Qt for Android environment in the first step includes the following operations:
operation 1: downloading and preparing Java jdk, Android sdk, Android adb, Android ndk, Android ant and Qt;
operation 2: sequentially installing and configuring java jdk, Android sdk, Android adb, Android ndk and Android ant;
operation 3: installing Qt for Android and starting a qtcreator.
And operation 4: and (4) configuring a software path and running and debugging.
And configuring a system environment to realize the operation of the Qt application program in the Android system.
In the fourth step, after the printed content is generated into a document by the Qt application program, the document is automatically backed up into a designated folder, on one hand, the document can be used as a backup file to be convenient for a user to use after the document is lost outside a source file, and on the other hand, the document can be directly called to be printed when repeated printing is carried out, so that the method is convenient and fast.
The folder is a hidden folder, the hidden folder has user access authority, the system automatically runs a screen locking program after three continuous times of access failures, the hidden folder can avoid mistaken deletion or other misoperation of a user, certain confidentiality is achieved, the hidden folder is prevented from being stolen by outsiders, the system also has access authority to perform safety protection even after being displayed, and the system can judge abnormal operation to perform system screen locking protection after three continuous times of access failures.
The backup document has a fixed temporary storage period which is 30-60d, and the backup document is automatically deleted after the period of time is over, so that the backup document can be prevented from occupying a large amount of memory for permanent storage, and can be basically judged as an expired document when the backup document is not called after the period of time is over 30-60d, so that the memory can be saved after the backup document is deleted, and the program running speed can be increased.
When the Qt application program backups the document, a limited access link is also established and can only be accessed by the Qt application program through the link, the Qt application program also provides a history calling window and displays the calling history document, the limited access link is provided with an extraction password, a user can conveniently and directly search the backup document through the history calling window after entering a Qt application page, the link is effective after clicking and quickly locates the backup document, the document can be directly called after inputting the extraction password, and the extraction password can be any number combination of 3-6 bits.
The specific flow in the fourth step is that by clicking a print button, a callObjectMethod is called by a Qt application program to acquire a printer service object on the Android device, a static callStaticMethod is called by the Qt application program through a JNI interface to transmit the printer service object as a parameter, a written JAVA code is called, and the printer service object is received.
The method comprises the steps of detecting an exception when a compiled JAVA code is called, immediately returning the JAVA code and throwing the exception if the JAVA code is called, continuously executing the code if the JAVA code is not called, finding a requested field when the JAVA code is called, generating NoSuchFieldError if the JAVA code is called, causing program crash if the native code is continuously operated without detecting the exception and using a field ID which is supposed to be returned by the native code, and actively throwing the exception when the JAVA code is called, so that the possibility of program crash can be greatly reduced.
In the fourth step, the JNI interface searches and globally caches the commonly used class, field ID and method ID, and sometimes, a large amount of work needs to be done in the JVM to obtain the call of the field or method, because the field and method may be relayed from the super class, which allows the JVM to traverse the class hierarchy upward to find them.
And in the sixth step, the Qt application program detects the state of the printer in real time through the return value printJobState of the printing function, receives the returned printing state value, checks the printing working condition, finally returns to the application interface, and displays the printing state for the user to check.
The invention can avoid the transplanting problem and the compatibility problem caused by using different printer types, correctly connect the printer and install the printer plug-in after integrating the Qt for Android environment on the Android device, simultaneously realize the communication between C/C + + and JAVA language by adopting the JNI technology, solve the problem that the Qt program in the prior art is difficult to conveniently use the printer because of the programming language, optimize the JNI technology, ensure the high efficiency and stability when the JNI interface executes the JAVA code by calling the abnormal detection and the establishment of the buffer zone when the JAVA code is called, in addition, provide the backup function of the printing service object for the user, and meet the repeated printing and historical backup requirements of the user as far as possible while protecting the privacy of the user, the invention can successfully realize the printing task by using different printer models or types through the Qt application printing scheme, the invention has the advantages that the development difficulty is reduced, the applicability is improved, the Hewlett packard USB ink-jet printer, the Hewlett packard laser printer, the Canon network laser printer and the Canon network ink-jet printer are verified, the operability is convenient and reliable, and the universal applicability on Qt onAndroid is realized.
The foregoing is only a preferred embodiment of the present invention; the scope of the invention is not limited thereto. Any person skilled in the art should be able to cover the technical scope of the present invention by equivalent or modified solutions and modifications within the technical scope of the present invention.

Claims (10)

1. A method for using a printer by an android platform QT program is characterized by comprising the following steps: the method comprises the following steps:
integrating a Qt for Android environment, preparing a printer with a USB or network interface, and correctly connecting an Android device;
reminding a user of installing the used printer plug-in on the Android equipment;
step three, after the printer plug-in is installed successfully, the printer plug-in is kept in an open state and waits to be called;
generating a document by the Qt application program according to the printed content, providing a printing button, calling a JNI interface to execute a JAVA code by clicking the button, using a printing function provided by an Android system under the JAVA programming environment, finally transferring the document content to a printer plug-in, and jumping to a printing interface, wherein the printing interface comprises document preview, printing parameters and the like;
step five, in the printing interface, the plug-in automatically finds the corresponding printer, clicks a printing button after selecting the printer, and finishes the printing work by the printer plug-in;
and step six, waiting for the printing end or abnormity.
2. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: the integration of the Qt for Android environment in the first step comprises the following operations:
operation 1: downloading and preparing Java jdk, Android sdk, Android adb, Android ndk, Android ant and Qt;
operation 2: sequentially installing and configuring java jdk, Android sdk, Android adb, Android ndk and Android ant;
operation 3: installing Qt for Android and starting a qtcreator.
And operation 4: and (4) configuring a software path and running and debugging.
3. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: and after the Qt application program in the fourth step generates a document from the printed content, automatically backing up the document into a specified folder.
4. The method for using the printer by the android platform QT program of claim 3, which is characterized in that: the folder is a hidden folder, the hidden folder has user access authority, and the system automatically operates a screen locking program after three continuous access failures.
5. The method for using the printer by the android platform QT program of claim 3, which is characterized in that: the backup file has a fixed temporary storage period which is 30-60d, and the backup file is automatically deleted after expiration.
6. The method for using the printer by the android platform QT program of claim 3, which is characterized in that: and when the Qt application program backups the document, a limited access link is established and can only be accessed by the Qt application program through the link, the Qt application program also provides a history calling window and displays the calling history document, and the limited access link is provided with an extraction password.
7. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: the specific process in the fourth step is that a printer service object on the Android device is obtained by calling an object method callObjectMethod under a Qt application program by clicking a printing button, the printer service object is transmitted out as a parameter by calling a static method callStaticMethod under the Qt application program through a JNI interface, a written JAVA code is called, and the printer service object is received at the same time.
8. The method for using the printer by the android platform QT program of claim 7, wherein the method comprises the following steps: and detecting the exception when the compiled JAVA code is called, if the exception occurs, returning the JAVA code immediately and throwing the exception, and if the exception does not occur, continuing to execute the code.
9. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: and searching and globally caching the commonly used class, field ID and method ID by the JNI interface in the step four.
10. The method for using the printer by the android platform QT program of claim 1, which is characterized in that: and in the sixth step, the Qt application program detects the state of the printer in real time through the return value printJobState of the printing function, receives the returned printing state value, checks the printing working condition, finally returns to an application interface, and displays the printing state for a user to check.
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CN112181328A (en) * 2020-11-30 2021-01-05 统信软件技术有限公司 Printing control system and method and computing device
CN112558892A (en) * 2020-12-22 2021-03-26 厦门喵宝科技有限公司 Portable intelligent printing device and control method
CN112677659A (en) * 2020-12-22 2021-04-20 厦门喵宝科技有限公司 Control method of portable intelligent printing device and printing device
CN112822193A (en) * 2021-01-05 2021-05-18 网易（杭州）网络有限公司 Application communication method, device, equipment and storage medium
CN112988092A (en) * 2021-04-08 2021-06-18 读书郎教育科技有限公司 Method and system compatible with multiple intelligent printers

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112181328A (en) * 2020-11-30 2021-01-05 统信软件技术有限公司 Printing control system and method and computing device
CN112558892A (en) * 2020-12-22 2021-03-26 厦门喵宝科技有限公司 Portable intelligent printing device and control method
CN112677659A (en) * 2020-12-22 2021-04-20 厦门喵宝科技有限公司 Control method of portable intelligent printing device and printing device
CN112558892B (en) * 2020-12-22 2022-06-14 厦门喵宝科技有限公司 Portable intelligent printing device and control method
CN112677659B (en) * 2020-12-22 2022-09-09 厦门喵宝科技有限公司 Control method of portable intelligent printing device and printing device
CN112822193A (en) * 2021-01-05 2021-05-18 网易（杭州）网络有限公司 Application communication method, device, equipment and storage medium
CN112822193B (en) * 2021-01-05 2023-03-24 网易（杭州）网络有限公司 Application communication method, device, equipment and storage medium
CN112988092A (en) * 2021-04-08 2021-06-18 读书郎教育科技有限公司 Method and system compatible with multiple intelligent printers

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