我在Delphi上的MediaLibrary有问题 .
我在我的主表单上创建了以下代码：
unit uPrincipal;
interface
uses
System.SysUtils, System.Types, System.UITypes, System.Classes,
System.Variants,FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics,
FMX.Dialogs,
FMX.Controls.Presentation, FMX.MultiView, FMX.Objects, FMX.Layouts,
FMX.StdCtrls, System.Actions, FMX.ActnList, FMX.StdActns,
FMX.MediaLibrary.Actions, FMX.MediaLibrary, FMX.Platform, System.Messaging;
type
TfmPrincipal = class(TForm)
Layout1: TLayout;
mvMenu: TMultiView;
rctMenuPrincipal: TRectangle;
rctMenuTop: TRectangle;
rctMenuBody: TRectangle;
rctOpHome: TRectangle;
rctBodyPrincipal: TRectangle;
tbPrincipal: TToolBar;
StyleBook1: TStyleBook;
sbMenu: TSpeedButton;
sbPhoto: TSpeedButton;
ActionList1: TActionList;
TakePhotoFromLibraryAction1: TTakePhotoFromLibraryAction;
Image1: TImage;
TakePhotoFromCameraAction1: TTakePhotoFromCameraAction;
procedure TakePhotoFromLibraryAction1DidFinishTaking(Image: TBitmap);
private
{ Private declarations }
public
{ Public declarations }
end;
var
fmPrincipal: TfmPrincipal;
implementation
{$R *.fmx}
{$R *.LgXhdpiPh.fmx ANDROID}
{$R *.NmXhdpiPh.fmx ANDROID}
{$R *.iPhone.fmx IOS}
uses uLogin, uTeste;
procedure TfmPrincipal.TakePhotoFromLibraryAction1DidFinishTaking(
Image: TBitmap);
begin
Image1.Bitmap.Assign(Image);
end;
end.
当我在手机上运行时，我点击SpeedButton，我收到“无效的类类型转换”错误消息 .
我在 TActionList 中添加了 TakePhotoFromLibraryAction1 ，并将其设置为SpeedButton的 Action .
我不知道为什么我会收到这个错误 .
1 回答
这是你的Delphi版本中的一个错误 .
一种解决方法是使用
TButton而不是TSpeedButton.另一种解决方法是从SpeedButton中删除
Action赋值，然后使用按钮的OnClick事件来调用操作的ExecuteTarget()方法，并将其作为Target参数传递给另一个控件 .