Android实例-屏幕操持常亮(XE8+小米2)

相关资料：

http://www.bubuko.com/infodetail-163304.html

结果：

1.打开权限Wake lock为True。

第三方单元：

  1 unit Android.JNI.PowerManager;
  2
  3 interface
  4
  5 function AcquireWakeLock : Boolean;
  6 procedure ReleaseWakeLock;
  7
  8 implementation
  9
 10 uses
 11   System.SysUtils,
 12   Androidapi.Helpers,
 13   Androidapi.JNI,
 14   Androidapi.JNIBridge,
 15   Androidapi.JNI.GraphicsContentViewText,
 16   Androidapi.JNI.JavaTypes,
 17   FMX.Helpers.Android;
 18
 19 type
 20   JPowerManager = interface;
 21   JWakeLock = interface;
 22   JWakeLockClass = interface(JObjectClass)
 23   [‘{918E171F-CDB8-4464-9507-F49272CE7636}‘]
 24   end;
 25
 26   [JavaSignature(‘android/os/PowerManager$WakeLock‘)]
 27   JWakeLock = interface(JObject)
 28   [‘{D17B1136-FA15-4AEB-85B1-2D490F0FD320}‘]
 29     {Methods}
 30     procedure acquire; cdecl;
 31     procedure release; cdecl;
 32     function isHeld: Boolean; cdecl;
 33   end;
 34
 35   TJWakeLock = class(TJavaGenericImport<JWakeLockClass, JWakeLock>) end;
 36   JPowerManagerClass = interface(JObjectClass)
 37   [‘{7D0696A2-ADEA-4158-AE1F-5E720DEDBCF9}‘]
 38     {Property methods}
 39     function _GetFULL_WAKE_LOCK: Integer; cdecl;
 40     function _GetSCREEN_BRIGHT_WAKE_LOCK: Integer; cdecl;
 41     function _GetSCREEN_DIM_WAKE_LOCK: Integer; cdecl;
 42     function _GetPARTIAL_WAKE_LOCK: Integer; cdecl;
 43     {Properties}
 44     //Keep screen on bright & keyboard on
 45     //Deprecated in API level 17 - Jelly Bean MR1
 46     property FULL_WAKE_LOCK: Integer read _GetFULL_WAKE_LOCK;
 47     //Keep screen on bright
 48     //Deprecated in API level 13 - Honeycomb MR2
 49     property SCREEN_BRIGHT_WAKE_LOCK: Integer read _GetSCREEN_BRIGHT_WAKE_LOCK;
 50     //Keep screen on dim
 51     //Deprecated in API level 17 - Jelly Bean MR1
 52     property SCREEN_DIM_WAKE_LOCK: Integer read _GetSCREEN_DIM_WAKE_LOCK;
 53     //Keep CPU running, screen & keyboard can go off
 54     property PARTIAL_WAKE_LOCK: Integer read _GetPARTIAL_WAKE_LOCK;
 55   end;
 56
 57   [JavaSignature(‘android/os/PowerManager‘)]
 58   JPowerManager = interface(JObject)
 59   [‘{DEAED658-4353-4D17-B0A3-8179E48BE87F}‘]
 60     {Methods}
 61     function newWakeLock(levelAndFlags: Integer; tag: JString): JWakeLock; cdecl;
 62   end;
 63
 64   TJPowerManager = class(TJavaGenericImport<JPowerManagerClass, JPowerManager>) end;
 65
 66   function GetPowerManager: JPowerManager;
 67   var
 68     PowerServiceNative: JObject;
 69   begin
 70     PowerServiceNative := SharedActivityContext.getSystemService(
 71       TJContext.JavaClass.POWER_SERVICE);
 72     if not Assigned(PowerServiceNative) then
 73       raise Exception.Create(‘Could not locate Power Service‘);
 74     Result := TJPowerManager.Wrap(
 75       (PowerServiceNative as ILocalObject).GetObjectID);
 76     if not Assigned(Result) then
 77       raise Exception.Create(‘Could not access Power Manager‘);
 78   end;
 79
 80 var
 81   WakeLock: JWakeLock = nil;
 82   function AcquireWakeLock: Boolean;
 83   var
 84     PowerManager: JPowerManager;
 85   begin
 86     Result := Assigned(WakeLock);
 87     if not Result then
 88     begin
 89       PowerManager := GetPowerManager;
 90       WakeLock := PowerManager.newWakeLock(
 91         TJPowerManager.JavaClass.SCREEN_BRIGHT_WAKE_LOCK,
 92         StringToJString(‘Runing‘));
 93       Result := Assigned(WakeLock);
 94     end;
 95     if Result then
 96     begin
 97       if not WakeLock.IsHeld then
 98       begin
 99         WakeLock.acquire;
100         Result := WakeLock.isHeld
101       end;
102     end;
103   end;
104
105 procedure ReleaseWakeLock;
106 begin
107   if Assigned(WakeLock) then
108   begin
109     WakeLock.release;
110     WakeLock := nil
111   end;
112 end;
113
114 end.

实例代码：

 1 unit Unit1;
 2
 3 interface
 4
 5 uses
 6   System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
 7   FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs,
 8   FMX.Controls.Presentation, FMX.StdCtrls;
 9
10 type
11   TForm1 = class(TForm)
12     Label1: TLabel;
13     Button1: TButton;
14     Button2: TButton;
15     procedure Button1Click(Sender: TObject);
16     procedure Button2Click(Sender: TObject);
17   private
18     { Private declarations }
19   public
20     { Public declarations }
21   end;
22
23 var
24   Form1: TForm1;
25
26 implementation
27 uses
28   Android.JNI.PowerManager;//需要引入
29 {$R *.fmx}
30 {$R *.NmXhdpiPh.fmx ANDROID}
31
32 procedure TForm1.Button1Click(Sender: TObject);
33 begin
34   AcquireWakeLock;//获取唤醒锁
35 end;
36
37 procedure TForm1.Button2Click(Sender: TObject);
38 begin
39   ReleaseWakeLock;//释放唤醒锁
40 end;
41
42 end.