Delphi XE5开发Android程序使用自定义字体文件.
万事大吉,只欠根据字体文件(.ttf文件)切换阅读字体,通常Android系统只带三种以下字体.一般用Java/Eclipse开发的话比较简单,typeface的createFromAsset,createFromFile之类的很容易使用. 但是由于FireMonkey是跨平台的类库,必然不能和平台帮得太紧,所以提供了抽象的封装. 但是也许Delphi XE5是Android平台的第一个版本,有些地方难免有疏漏,FireMonkey的封装没有提供更换字体的功能.
但是我要实现的电子书阅读器换字体几乎是必须要实现的功能,所以只能给FireMonkey动动小手术了.
FireMonkey的字体加载是由抽象类TFontGlyphManager来实现的,在各个具体平台又有不同的实现,TWinFontGlyphManager,TIOSFontGlyphManager,TMacFontGlyphManager,TAndroidFontGlyphManager.
我们这里只针对Android不能加载字体文件换字体进行手术.
把TAndroidFontGlyphManager的实现单元FMX.FontGlyphs.Android拷贝到我们自己要使用更换字的的工程的目录中.修改TAndroidFontGlyphManager.LoadResource方法,当应用某字体的时候先判断我们指定的目录中是否存在同名的.ttf文件.有的话优先使用我们的字体文件.
做了两处改动.一处是uses添加了System.IOUtils单元.一处是TAndroidFontGlyphManager.LoadResource. 在这里做这样的小手术好处是我们的程序不收任何影响.例如: Text1.Font.Family:=’微软雅黑’; Text2.Font.Family:=’楷体’; 那么只要在我们指定的目录中存在”楷体.ttf”和”微软雅黑.ttf”那么这两个控件的字体就会分别应用对应的字体文件.
希望XE6版本中Android能投提供一种让我们动态加载字体的办法.不过也许我这个不是一个大众需求,毕竟大多数Android软件不需要太多的字体文件,在系统两三款字体下也活得好好的.
下面贴出来我修改过的文件.
{ ******************************************************* } { } { Delphi FireMonkey Platform } { Copyright(c) 2013 Embarcadero Technologies, Inc. } { } { ******************************************************* } unit FMX.FontGlyphs.Android; interface uses System.Types, System.Classes, System.SysUtils, System.UITypes, System.UIConsts, System.Generics.Collections, FMX.Types, FMX.Surfaces, FMX.FontGlyphs, FMX.PixelFormats, Androidapi.JNI.JavaTypes, Androidapi.JNI.GraphicsContentViewText, Androidapi.JNIBridge; {$SCOPEDENUMS ON} type TAndroidFontGlyphManager = class(TFontGlyphManager) private FPaint: JPaint; // Current metrics FSpacing: Single; FTop: Single; FTopInt: Integer; FAscent: Single; FDescent: Single; FBottom: Single; FBottomInt: Integer; FLeading: Single; FLeadingInt: Integer; protected procedure LoadResource; override; procedure FreeResource; override; function DoGetGlyph(const Char: UCS4Char; const Settings: TFontGlyphSettings): TFontGlyph; override; public constructor Create; destructor Destroy; override; end; implementation uses System.Math, System.Character, Androidapi.Bitmap, //引入System.IOUtils是为了能够获取Android的各种系统目录 System.IOUtils, // FMX.Graphics; { TAndroidFontGlyphManager } constructor TAndroidFontGlyphManager.Create; begin inherited Create; FPaint := TJPaint.Create; end; destructor TAndroidFontGlyphManager.Destroy; begin FPaint := nil; inherited; end; procedure TAndroidFontGlyphManager.LoadResource; const BoldAndItalic = [TFontStyle.fsBold, TFontStyle.fsItalic]; var TypefaceFlag: Integer; Typeface: JTypeface; FamilyName: JString; Metrics: JPaint_FontMetrics; MetricsInt: JPaint_FontMetricsInt; FontFile: string; begin FPaint.setAntiAlias(True); FPaint.setTextSize(CurrentSettings.Size * CurrentSettings.Scale); FPaint.setARGB(255, 255, 255, 255); FPaint.setUnderlineText(TFontStyle.fsUnderline in CurrentSettings.Style); FPaint.setStrikeThruText(TFontStyle.fsStrikeOut in CurrentSettings.Style); if TOSVersion.Check(4, 0) then FPaint.setHinting(TJPaint.JavaClass.HINTING_ON); // Font try FamilyName := StringToJString(CurrentSettings.Family); if (BoldAndItalic * CurrentSettings.Style) = BoldAndItalic then TypefaceFlag := TJTypeface.JavaClass.BOLD_ITALIC else if TFontStyle.fsBold in CurrentSettings.Style then TypefaceFlag := TJTypeface.JavaClass.BOLD else if TFontStyle.fsItalic in CurrentSettings.Style then TypefaceFlag := TJTypeface.JavaClass.ITALIC else TypefaceFlag := TJTypeface.JavaClass.NORMAL; { Fix Begin 修改开始.如果在下载目录中存在跟字体同名的.ttf文件,那么优先使用ttf文件. 我是放在SD卡的下载目录中.大家可以按需要任意改这个位置. 甚至也可以放在Asset目录中,这样可以打包在APK中. } FontFile := TPath.GetSharedDownloadsPath + PathDelim + CurrentSettings.Family + '.ttf'; if FileExists(FontFile) then Typeface := TJTypeface.JavaClass.createFromFile(StringToJString(FontFile)) else Typeface := TJTypeface.JavaClass.Create(FamilyName, TypefaceFlag); { Fix End 修改结束 } FPaint.setTypeface(Typeface); try Metrics := FPaint.getFontMetrics; MetricsInt := FPaint.getFontMetricsInt; // FSpacing := FPaint.getFontMetrics(Metrics); FTop := Metrics.top; FTopInt := MetricsInt.top; FAscent := Metrics.ascent; FDescent := Metrics.descent; FBottom := Metrics.bottom; FBottomInt := MetricsInt.bottom; FLeading := Metrics.leading; FLeadingInt := MetricsInt.leading; // SysDebug(FloatToStr(CurrentSettings.Size) + ':' + FloatToStr(CurrentSettings.Scale)); // Log.d(Format('Top=(%d %f) Bottom=(%d %f) Leading=(%d %f) FAscent=(%d %f)', [FTopInt, FTop, FBottomInt, FBottom, FLeadingInt, FLeading, MetricsInt.ascent, FAscent])); finally Metrics := nil; MetricsInt := nil; end; finally FamilyName := nil; Typeface := nil; end; end; procedure TAndroidFontGlyphManager.FreeResource; begin if Assigned(FPaint) then FPaint.reset; end; function TAndroidFontGlyphManager.DoGetGlyph(const Char: UCS4Char; const Settings: TFontGlyphSettings): TFontGlyph; var Text: JString; Bitmap: JBitmap; Canvas: JCanvas; GlyphRect: TRect; C, I, J, Width, Height: Integer; Advance: Single; Bounds: JRect; GlyphStyle: TFontGlyphStyles; PixelBuffer: Pointer; Data: PIntegerArray; Path: JPath; PathMeasure: JPathMeasure; PathLength: Single; Coords: TJavaArray<Single>; StartPoint, LastPoint, Point: TPointF; NewContour, HasStartPoint: Boolean; begin try Text := StringToJString(System.Char.ConvertFromUtf32(Char)); Advance := FPaint.measureText(Text); // SysDebug(Format('%s %f', [System.Char.ConvertFromUtf32(Char), Advance])); Height := Abs(FTopInt) + Abs(FBottomInt) + 2; Width := Ceil(Abs(Advance)) + 2; try Bitmap := TJBitmap.JavaClass.createBitmap(Width, Height, TJBitmap_Config.JavaClass.ARGB_8888); try Bounds := TJRect.Create; FPaint.getTextBounds(Text, 0, Text.length, Bounds); // Log.d(Format('Bounds=(%d %d %d %d) %d %d ', [Bounds.left, Bounds.top, Bounds.right, Bounds.bottom, Bounds.width, Bounds.height])); try Canvas := TJCanvas.JavaClass.init(Bitmap); Canvas.drawText(Text, 0, -Trunc(FAscent), FPaint); finally Canvas := nil; end; GlyphStyle := []; if ((FAscent = 0) and (FDescent = 0)) or not HasGlyph(Char) then GlyphStyle := [TFontGlyphStyle.NoGlyph]; if TFontGlyphSetting.gsPath in Settings then GlyphStyle := GlyphStyle + [TFontGlyphStyle.HasPath]; Result := TFontGlyph.Create(TPoint.Create(Bounds.left, Abs(FTopInt - Bounds.top)), Advance, Abs(FTopInt) + Abs(FBottomInt) + Abs(FLeadingInt), GlyphStyle); if (TFontGlyphSetting.gsBitmap in Settings) and (HasGlyph(Char) or ((FAscent <> 0) or (FDescent <> 0))) and (AndroidBitmap_lockPixels(TJNIResolver.GetJNIEnv, (Bitmap as ILocalObject).GetObjectID, @PixelBuffer) = 0) then begin Data := PIntegerArray(PixelBuffer); GlyphRect.left := Bounds.left; GlyphRect.Right := Bounds.Right; GlyphRect.top := Abs(Trunc(FAscent) - Bounds.top); GlyphRect.bottom := Abs(Trunc(FAscent) - Bounds.bottom); // Log.d(Format('GlyphRect=(%d %d %d %d) %d %d', [GlyphRect.Left, GlyphRect.Top, GlyphRect.Right, GlyphRect.Bottom, GlyphRect.Width, GlyphRect.Height])); if (GlyphRect.Width > 0) or (GlyphRect.Height > 0) then begin Result.Bitmap.SetSize(GlyphRect.Width + 1, GlyphRect.Height + 1, TPixelFormat.pfA8R8G8B8); if TFontGlyphSetting.gsPremultipliedAlpha in Settings then begin for I := GlyphRect.top to GlyphRect.bottom do Move(Data[I * Width + Max(GlyphRect.left, 0)], Result.Bitmap.GetPixelAddr(0, I - GlyphRect.top)^, Result.Bitmap.Pitch); end else for I := GlyphRect.top to GlyphRect.bottom - 1 do for J := GlyphRect.left to GlyphRect.Right - 1 do begin C := Data[I * Width + J]; if C <> 0 then begin C := ((C shr 16) and $FF + (C shr 8) and $FF + (C and $FF)) div 3; Result.Bitmap.Pixels[J - GlyphRect.left, I - GlyphRect.top] := MakeColor($FF, $FF, $FF, C); end end; end; AndroidBitmap_unlockPixels(TJNIResolver.GetJNIEnv, (Bitmap as ILocalObject).GetObjectID); end; // Path if TFontGlyphSetting.gsPath in Settings then try Path := TJPath.Create; FPaint.getTextPath(Text, 0, Text.length, Result.Origin.X, Result.Origin.Y, Path); PathMeasure := TJPathMeasure.Create; PathMeasure.setPath(Path, False); Coords := TJavaArray<Single>.Create(2); if PathMeasure.getLength > 0 then repeat PathLength := PathMeasure.getLength; NewContour := True; HasStartPoint := False; I := 0; while I < PathLength do begin if PathMeasure.getPosTan(I, Coords, nil) then begin Point := PointF(Coords[0], Coords[1]); if NewContour then begin Result.Path.MoveTo(Point); NewContour := False; HasStartPoint := False; end else if Point <> LastPoint then begin if HasStartPoint and (LastPoint <> StartPoint) then if not SameValue (((Point.Y - StartPoint.Y) / (Point.X - StartPoint.X) ), ((Point.Y - LastPoint.Y) / (Point.X - LastPoint.X) ), Epsilon) then begin Result.Path.LineTo(Point); HasStartPoint := False; end else else Result.Path.LineTo(Point); end; LastPoint := Point; if not HasStartPoint then begin StartPoint := Point; HasStartPoint := True; end; end; Inc(I); end; if Result.Path.Count > 0 then Result.Path.ClosePath; until not PathMeasure.nextContour; Point := Result.Path.GetBounds.TopLeft; Result.Path.Translate(-Point.X + Result.Origin.X, -Point.Y + Result.Origin.Y); finally FreeAndNil(Coords); Path := nil; PathMeasure := nil; end; finally Bounds := nil; end; finally Bitmap.recycle; Bitmap := nil; end; finally Text := nil; end; end; end.
