Multiple application instances in operating systems that utilize a single process for application execution
Various examples for providing multiple instances of a client application in operating systems that limit execution of the client application to a single process are disclosed. A client device can include an operating system natively configured to generate a single process for an execution of the client application on the client device. A client application can be configured to, in the single process, generate sub-processes for execution of separate instances of the client application. The client application can include at least one user interface that permits creation of, termination of, or toggling between various instances of the client application.
1. A system for providing multiple instances of a client application, comprising:
a client device comprising at least one hardware processor; and
program instructions executable in the client device that, when executed by the client device, cause the client device to:
provide an operating system natively configured to generate a single process for an execution of the client application on the client device based on an interpretation of a manifest file of the client application;
in response to an indication to execute the client application, generate the single process for the execution of a default routine of the client application, wherein the default routine of the client application is configured to, in the single process:
generate a first sub-process for execution of a first instance of the client application, the first sub-process being a first sub-routine extending from the default routine and having a corresponding process attribute in the manifest file;
generate a second sub-process for execution of a second instance of the client application, the second sub-process being a second sub-routine extending from the default routine and having a corresponding process attribute in the manifest file; and
maintain a first state of the first instance and a second state of the second instance; and
display at least one user interface that permits a selection of the first instance of the client application or the second instance of the client application.
2. The system of claim 1 , wherein the client application comprises a startup activity routine that is performed in response to an initial execution of the client application in the single process, the startup activity routine being configured to:
provide the at least one user interface that permits the selection of the first instance of the client application or the second instance of the client application; or
make active the first instance of the client application or the second instance of the client application.
3. The system of claim 2 , wherein the selection of the first instance of the client application in the at least one user interface makes the first instance of the client application active in the operating system; and
wherein the selection of the second instance of the client application in the at least one user interface makes the second instance of the client application active in the operating system.
4. The system of claim 2 , wherein the client application comprises:
a first startup activity sub-routine of the startup activity routine for execution of the first instance of the client application in the first sub-process; and
a second startup activity sub-routine of the startup activity routine for execution of the second instance of the client application in the second sub-process.
5. The system of claim 1 , wherein the first sub-process and the second sub-process each comprise an onDestroy routine comprising code that, when executed upon termination of a respective one of the multiple instances, returns an identifier corresponding to a terminated one of the multiple instances.
6. The system of claim 1 , wherein:
the first instance of the client application and the second instance of the client application are a portion of a plurality of instances of the client application; and
the program instructions, when executed by the client device, further cause the client device to maintain a list comprising a plurality of data structures, individual ones of the plurality of data structures in the list corresponding to active ones of the plurality of instances of the client application.
7. The system of claim 1 , wherein the operating system is a mobile operating system.
8. A non-transitory computer-readable medium for providing multiple instances of a client application embodying program code executable in a client device that, when executed by the client device, causes the client device to:
provide an operating system natively configured to generate a single process for an execution of the client application on the client device based on an interpretation of a manifest file of the client application;
in response to an indication to execute the client application, generate the single process for the execution of a default routine of the client application, wherein the default routine of the client application is configured to, in the single process:
generate a first sub-process for execution of a first instance of the client application, the first sub-process being a first sub-routine extending from the default routine and having a corresponding process attribute in the manifest file;
generate a second sub-process for execution of a second instance of the client application, the second sub-process being a second sub-routine extending from the default routine and having a corresponding process attribute in the manifest file; and
maintain a first state of the first instance and a second state of the second instance; and
display at least one user interface that permits a selection of the first instance of the client application or the second instance of the client application.
9. The non-transitory computer-readable medium of claim 8 , wherein the client application comprises a startup activity routine that is performed in response to an initial execution of the client application in the single process, the startup activity routine being configured to:
provide the at least one user interface that permits the selection of the first instance of the client application or the second instance of the client application; or
make active the first instance of the client application or the second instance of the client application.
10. The non-transitory computer-readable medium of claim 9 , wherein the selection of the first instance of the client application in the at least one user interface makes the first instance of the client application active in the operating system; and
wherein the selection of the second instance of the client application in the at least one user interface makes the second instance of the client application active in the operating system.
11. The non-transitory computer-readable medium of claim 9 , wherein the client application comprises:
a first startup activity sub-routine of the startup activity routine for execution of the first instance of the client application in the first sub-process; and
a second startup activity sub-routine of the startup activity routine for execution of the second instance of the client application in the second sub-process.
12. The non-transitory computer-readable medium of claim 8 , wherein the first sub-process and the second sub-process each comprise an onDestroy routine comprising code that, when executed upon termination of a respective one of the multiple instances, returns an identifier corresponding to a terminated one of the multiple instances.
13. The non-transitory computer-readable medium of claim 8 , wherein:
the first instance of the client application and the second instance of the client application are a portion of a plurality of instances of the client application; and
the program instructions, when executed by the client device, further cause the client device to maintain a list comprising a plurality of data structures, individual ones of the plurality of data structures in the list corresponding to active ones of the plurality of instances of the client application.
14. The non-transitory computer-readable medium of claim 8 , wherein the operating system is a mobile operating system.
15. A computer-implemented method for providing multiple instances of a client application on a client device, comprising:
providing an operating system natively configured to generate a single process for an execution of the client application on the client device based on an interpretation of a manifest file of the client application;
in response to an indication to execute the client application, generating the single process for the execution of a default routine of the client application, wherein the default routine of the client application is configured to, in the single process:
generate a first sub-process for execution of a first instance of the client application, the first sub-process being a first sub-routine extending from the default routine and having a corresponding process attribute in the manifest file;
generate a second sub-process for execution of a second instance of the client application, the second sub-process being a second sub-routine extending from the default routine and having a corresponding process attribute in the manifest file; and
maintain a first state of the first instance and a second state of the second instance; and
displaying at least one user interface that permits a selection of the first instance of the client application or the second instance of the client application.
16. The computer-implemented method of claim 15 , wherein the client application comprises a startup activity routine that is performed in response to an initial execution of the client application in the single process, the startup activity routine being configured to:
provide the at least one user interface that permits the selection of the first instance of the client application or the second instance of the client application; or
make active the first instance of the client application or the second instance of the client application.
17. The computer-implemented method of claim 16 , wherein the selection of the first instance of the client application in the at least one user interface makes the first instance of the client application active in the operating system; and
wherein the selection of the second instance of the client application in the at least one user interface makes the second instance of the client application active in the operating system.
18. The computer-implemented method of claim 16 , wherein the client application comprises:
a first startup activity sub-routine of the startup activity routine for execution of the first instance of the client application in the first sub-process; and
a second startup activity sub-routine of the startup activity routine for execution of the second instance of the client application in the second sub-process.
19. The computer-implemented method of claim 15 , wherein the first sub-process and the second sub-process each comprise an onDestroy routine comprising code that, when executed upon termination of a respective one of the multiple instances, returns an identifier corresponding to a terminated one of the multiple instances.
20. The computer-implemented method of claim 15 , wherein the operating system is a mobile operating system.