[FMX] Switches the Android app to the background and switches from the background to the foreground implementation

Sometimes we need to switch our Android program to run in the background and switch it to the foreground if necessary. The following provides a way to do this by first referencing three cells:

1	Uses androidapi. JNI. App,androidapi. JNI. Graphicscontentviewtext,androidapi. Helpers;

To switch the application to the background, there are two ways of switching the app back to the desktop, which is equivalent to pressing the Home key after execution:

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procedure sendapptoback(Sender: tobject); var Intent:jintent; beginIntent: = tjintent. Create; Intent. Setaction(tjintent. Javaclass. Action_main); Intent. SetFlags(tjintent. Javaclass. Flag_activity_new_task); Intent. Addcategory(tjintent. Javaclass. Category_home); sharedactivitycontext. StartActivity(intent); end;

Another option is to call the Jactivitymanager.movetasktoback function, which is equivalent to pressing the return key, but the program does not exit. First we need to implement a Activitymanager service instance, XE7 does not provide a default function, we imitate write a, this function in the back of the program to the foreground when the need to use:

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function sharedactivitymanager: jactivitymanager; var aservice: jobject; beginaservice := sharedactivitycontext. Getsystemservice (tjcontext. Javaclass. Activity_service Result : = tjactivitymanager. Wrap((aservice as ilocalobject). Getobjectid); end;

Now switch to the background, just one line of code:

1234	procedure sendapptoback; begin Sharedactivitymanager. Movetasktoback(sharedactivity. GetTaskID,tjintent. Javaclass. Flag_activity_new_task); end;

In turn, switching to the foreground requires only a single line of code:

delphi/pascal

1234	procedure Bringapptofront begin sharedactivitymanager. Movetasktofront (sharedactivity.gettaskid,tjintent.< Span class= "crayon-v" >javaclass. Flag_activity_new_task end;

With Movetasktoback/movetasktofront, it is important to note that the application needs to be authorized reorder tasks (check it out in the project settings).

[FMX] Switches the Android app to the background and switches from the background to the foreground implementation