【发布时间】：2021-07-30 10:04:47
【问题描述】：
我有一个使用 Itext 5 并按预期工作的项目。 程序必须将 userInput 放在段落内的某些“块”中。段落每行有不可移动的（块）字，用户输入应该在为用户输入保留的空间内缩放。 旧项目有以下代码（作为示例）
public class Oldway {
static final transient Font bold2 = FontFactory.getFont("Times-Roman", 10.0f, 1);
public static void main(String[] args) {
Document document = new Document();
document.setPageSize(PageSize.A4);
try {
PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(new File("itext5.pdf")));
document.open();
Paragraph title = new Paragraph("Title of doc");
title.setAlignment(1);
document.add(title);
Paragraph dec= new Paragraph();
Chunk ch01 = new Chunk("Prev text ");
dec.add(ch01);
Chunk ch02 = new Chunk(getEmptySpace(42));
dec.add(ch02);
Chunk ch03 = new Chunk(" next Text");
dec.add(ch03);
document.add(dec);
float y = writer.getVerticalPosition(false);
float x2 = document.left() + ch01.getWidthPoint();
float x3 = x2 + ch02.getWidthPoint();
getPlainFillTest("Text to insert", document, y, x3, x2, writer, false);
document.close();
writer.flush();
} catch (FileNotFoundException | DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Chunk getEmptySpace(int size) {
Chunk ch = new Chunk();
for(int i = 0;i<=size;i++) {
ch.append("\u00a0");
}
return new Chunk(ch);
}
public static void getPlainFillTest(String str,Document document,float y, float x1pos,
float x2pos, PdfWriter writer,boolean withTab) {
if(str.isEmpty() || str.isBlank()) {
str = "________";
}
Rectangle rec2 = null;
if(!withTab)
rec2 = new Rectangle(x2pos, y, x1pos-2,y+10);
else {
rec2 = new Rectangle(x2pos+35, y, x1pos+33,y+10);
}
BaseFont bf = bold2.getBaseFont();
PdfContentByte cb = writer.getDirectContent();
float fontSize = getMaxFontSize(bf, str,(int)rec2.getWidth(), (int)rec2.getHeight());
Phrase phrase = new Phrase(str, new Font(bf, fontSize));
ColumnText.showTextAligned(cb, Element.ALIGN_CENTER, phrase,
// center horizontally
(rec2.getLeft() + rec2.getRight()) / 2,
// shift baseline based on descent
rec2.getBottom() - bf.getDescentPoint(str, fontSize),0);
cb.saveState();//patrulaterul albastru
cb.setColorStroke(Color.BLUE);
cb.rectangle(rec2.getLeft(), rec2.getBottom(), rec2.getWidth(), rec2.getHeight());
cb.stroke();
cb.restoreState();
}
//stackoverflow solution
private static float getMaxFontSize(BaseFont bf, String text, int width, int height){
// avoid infinite loop when text is empty
if(text.isEmpty()){
return 0.0f;
}
float fontSize = 0.1f;
while(bf.getWidthPoint(text, fontSize) < width){
fontSize += 0.1f;
}
float maxHeight = measureHeight(bf, text, fontSize);
while(maxHeight > height){
fontSize -= 0.1f;
maxHeight = measureHeight(bf, text, fontSize);
};
return fontSize;
}
public static float measureHeight(BaseFont baseFont, String text, float fontSize)
{
float ascend = baseFont.getAscentPoint(text, fontSize);
float descend = baseFont.getDescentPoint(text, fontSize);
return ascend - descend;
}}
现在我正尝试在 IText 7 中做同样的事情，但……没那么容易！ 我设法创建了一个工作代码，但它很乱，有些东西没有得到正确的坐标。 Itext7代码（作为示例）：
public class Newway {
public static void main(String[] args) {
PdfWriter writer;
try {
writer = new PdfWriter(new File("test2.pdf"));
PdfDocument document = new PdfDocument(writer);
document.getDocumentInfo().addCreationDate();
document.getDocumentInfo().setTitle("Title");
document.setDefaultPageSize(PageSize.A4);
Document doc = new Document(document);
doc.setFontSize(12);
Paragraph par = new Paragraph();
Text ch01 = new Text("Prev Text ");
par.add(ch01);
Paragraph space = new Paragraph();
space.setMaxWidth(40);
for(int i=0;i<40;i++) {
par.add("\u00a0");
space.add("\u00a0");
}
Text ch02 = new Text(" next text");
par.add(ch02);
doc.add(par);
Paragraph linePara = new Paragraph().add("Test from UserInput")
.setTextAlignment(TextAlignment.CENTER).setBorder(new DottedBorder(1));
float width = doc.getPageEffectiveArea(PageSize.A4).getWidth();
float height = doc.getPageEffectiveArea(PageSize.A4).getHeight();
IRenderer primul = ch01.createRendererSubTree().setParent(doc.getRenderer());
IRenderer spaceR = space.createRendererSubTree().setParent(doc.getRenderer());
LayoutResult primulResult = primul.layout(new LayoutContext(new LayoutArea(1, new Rectangle(width,height))));
LayoutResult layoutResult = spaceR.layout(new LayoutContext(new LayoutArea(1, new Rectangle(width,height))));
Rectangle primulBox = ((TextRenderer) primul).getInnerAreaBBox();
Rectangle rect = ((ParagraphRenderer) spaceR).getInnerAreaBBox();
float rwidth = rect.getWidth();
float rheight = rect.getHeight();
float x = primulBox.getWidth()+ doc.getLeftMargin();
float y = rect.getY()+(rheight*2.05f);//rect.getY() is never accurate, is always below the paragraph. WHY ??
Rectangle towr = new Rectangle(x, y, rwidth, rheight*1.12f);//rheight on default is way too small
PdfCanvas pdfcanvas = new PdfCanvas(document.getFirstPage());
Canvas canvas = new Canvas(pdfcanvas, towr);
//from theinternet
float fontSizeL = 1;
float fontSizeR = 14;
while (Math.abs(fontSizeL - fontSizeR) > 1e-1) {
float curFontSize = (fontSizeL + fontSizeR) / 2;
linePara.setFontSize(curFontSize);
// It is important to set parent for the current element renderer to a root renderer
IRenderer renderer = linePara.createRendererSubTree().setParent(canvas.getRenderer());
LayoutContext context = new LayoutContext(new LayoutArea(1, towr));
if (renderer.layout(context).getStatus() == LayoutResult.FULL) {
// we can fit all the text with curFontSize
fontSizeL = curFontSize;
} else {
fontSizeR = curFontSize;
}
}
canvas.add(linePara);
new PdfCanvas(document.getFirstPage()).rectangle(towr).setStrokeColor(ColorConstants.BLACK).stroke();
canvas.close();
doc.close();
writer.flush();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}}
问题是
- 有没有更好、更优雅的方法来做到这一点？
- 为什么 rect.getY() 总是在段落下方？以及如何让 Y 与段落实际 Y 坐标相匹配？
- 为什么默认的 'rheight' 总是太小？但是 (rheight*1.1f) 有效吗？
- （可选）如何在 IText 7 中设置 tab() 空间大小？
【问题讨论】：
-
问题 4 似乎与您当前代码的其他 3 个问题完全无关。提出一个单独的问题并正确描述您要实现的目标以及您当前拥有的代码是最有意义的（我在当前代码中看不到任何选项卡）
标签： optimization itext itext7