我有一个压缩的图像我试图接收它并在Android平台上显示它,在vcl中我一直在做类似的事情
procedure TForm1.CreateJpg(Data: string);
var
JpegStream: TMemoryStream;
JpegImage: TJPEGImage;
Bitmap: TBitmap;
tmpPos, tmpLen: integer;
pp: string;
begin
try
tmpPos := Pos('B]>', Data);
pp := Copy(Data, 5, tmpPos - 5);
tmpLen := StrToInt(pp);
Data := Copy(Data, tmpPos + 3, tmpLen);
Bitmap := TBitmap.Create;
try
JpegImage := TJPEGImage.Create;
try
JpegStream := TMemoryStream.Create;
try
TIdDecoderMIME.DecodeStream(Data, JpegStream);
JpegStream.Position := 0;
JpegImage.LoadFromStream(JpegStream);
finally
JpegStream.Free;
end;
with Bitmap do
begin
Canvas.Lock;
try
Width := JpegImage.Width;
Height := JpegImage.Height;
Canvas.StretchDraw(rect(0, 0, 200, 160), JpegImage);
finally
Canvas.Unlock;
end;
end;
finally
JpegImage.Free;
end;
img.Assign(Bitmap);
finally
Bitmap.Free;
end;
except
on E: Exception do
//
end;
end;
但是我不能对android做同样的事情,因为没有TJPEGIMAGE
库的声明我不确定我是否可以在JPEG
上做Fire-monkey
的替代,我很困惑我必须做什么
答案 0 :(得分:3)
VCL使用TGraphic
派生类来处理各个图像类型。但是,FireMonkey中没有等效的TGraphic
。它只有一个TBitmap
类,支持多种图像类型。不同的FMX平台支持不同的图像类型子集(有关完整列表,请参阅Supported Image Formats)。幸运的是,JPG是所有FMX平台支持的两种图像类型之一(PNG是另一种)。
您的VCL代码的FMX等价物如下所示:
procedure TForm1.CreateJpg(Data: string);
var
JpegStream: TMemoryStream;
Jpeg, Bitmap: TBitmap;
tmpPos, tmpLen: integer;
pp: string;
begin
try
tmpPos := Pos('B]>', Data);
pp := Copy(Data, 5, tmpPos - 5);
tmpLen := StrToInt(pp);
Data := Copy(Data, tmpPos + 3, tmpLen);
Bitmap := TBitmap.Create;
try
Jpeg := TBitmap.Create;
try
JpegStream := TMemoryStream.Create;
try
TIdDecoderMIME.DecodeStream(Data, JpegStream);
JpegStream.Position := 0;
Jpeg.LoadFromStream(JpegStream);
finally
JpegStream.Free;
end;
with Bitmap do
begin
SetSize(Jpeg.Width, Jpeg.Height);
if Canvas.BeginScene then
try
Canvas.DrawBitmap(Jpeg,
{$IF RTLVersion >= 31} // 10.1 Berlin or higher
Jpeg.BoundsF,
{$ELSE}
TRectF.Create(0, 0, Jpeg.Width, Jpeg.Height),
{$IFEND}
TRectF.Create(0, 0, 200, 160), 1.0);
finally
Canvas.EndScene;
end;
end;
finally
Jpeg.Free;
end;
img.Bitmap.Assign(Bitmap);
finally
Bitmap.Free;
end;
except
on E: Exception do
//
end;
end;