我一直很高兴在 Android PDF 类 PdfDocument 中生成 PDF 文档。在对“微妙”文档感到困惑之后,我猜想坐标系在 PostScript 中(1/72“)
private static final int A4_WIDTH = 595;
private static final int A4_HEIGHT = 842;
private static final int CM = 28;
private static final int footer_height = CM;
void startPage() {
if (currentPage != null) {
finishPage(currentPage);
}
PageInfo.Builder pageBuilder = new PageInfo.Builder(A4_WIDTH, A4_HEIGHT, page++);
Rect rect = new Rect(0, 0, A4_WIDTH, A4_HEIGHT);
rect.inset(CM, 2 * CM);
pageBuilder.setContentRect(rect);
PageInfo pageInfo = pageBuilder.create();
pagePosition = 0.0f;
pageWidth = rect.width();
pageHeight = rect.height();
currentPage = super.startPage(pageInfo);
page_count++;
if (has_footer)
putFooter();
}
这在我的 Nexus 10 上运行良好,但是当在三星 S6 上的坐标系似乎混乱时,我感到相当惊讶,所以在 Nexus 10 上,我将文本设置为 0,0,它非常适合向下 2 厘米和 1 厘米宽,但在 S6 上它看起来向下 4 厘米,宽 2 厘米。此外,底部和右侧被剪裁了 2 厘米和 1 厘米。换句话说,剪切矩形在正确的位置,但似乎坐标系已经被双重偏移。
我的绘图代码如下所示:
canvas.save();
canvas.translate(0, pagePosition);
staticLayout.draw(canvas);
canvas.restore();
其中 pagePosition 是一个简单的 ps 计数器,通过从 staticLayout.getHeight() 的结果测量文本来驱动;
需要明确的是,布局是正确的,在文本、线条图和图像的相当复杂的组合上没有任何缺点,只是得到了这个与设备相关的缺点。
虫子还是我的大脑?
编辑:左边是 Nexus,右边是 S6
生成代码:
import android.annotation.TargetApi;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.pdf.PdfDocument;
import android.support.v4.content.ContextCompat;
import uk.co.spennycycles.pocketcycletech.PocketCycleTechApp;
import uk.co.spennycycles.pocketcycletech.R;
@TargetApi(19)
public class TestReport extends PdfDocument {
private static final String TAG = SpennyPdfDocument.class.getSimpleName();
private static final int A4_WIDTH = 595;
private static final int A4_HEIGHT = 842;
private static final int CM = 28;
int pageWidth;
int pageHeight;
public void generateReport() {
PageInfo.Builder pageBuilder = new PageInfo.Builder(A4_WIDTH, A4_HEIGHT, 1);
Rect rect = new Rect(0, 0, A4_WIDTH, A4_HEIGHT);
rect.inset(CM, 2 * CM);
pageBuilder.setContentRect(rect);
PageInfo pageInfo = pageBuilder.create();
Page page = super.startPage(pageInfo);
pageWidth = rect.width();
pageHeight = rect.height();
Canvas canvas = page.getCanvas();
RectF r = new RectF((float) 0, 0, pageWidth, pageHeight);
r.inset(1.0f, 1.0f);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setDither(true);
paint.setStyle(Paint.Style.FILL);
paint.setColor(ContextCompat.getColor(PocketCycleTechApp.getContext(), R.color.lt_gray));
canvas.drawRect(r, paint);
paint.setColor(ContextCompat.getColor(PocketCycleTechApp.getContext(), R.color.black));
paint.setStrokeWidth(2.0f);
paint.setStyle(Paint.Style.STROKE);
canvas.drawRect(r, paint);
paint.setStyle(Paint.Style.FILL_AND_STROKE);
canvas.drawLine(r.left, r.top, r.right, r.bottom, paint);
canvas.drawLine(r.right, r.top, r.left, r.bottom, paint);
finishPage(page);
}
}