Android PdfDocument

Question

我很高兴在Android PDF类PdfDocument中制作PDF文档。在迷惑了＆＃34;微妙的＆＃34;文档我认为坐标系是PostScript（1/72＆＃34;）

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上工作得很好，但是当我在三星S6上时坐标系看起来很乱，我感到非常惊讶，所以在Nexus 10上我把文字放在0,0并且它很适合2厘米向下和1厘米对面，但是在S6上它显示4厘米向下和2厘米横跨。此外，底部和右部被夹住2cm和1cm。换句话说，剪切矩形位于正确的位置，但看起来坐标系已经双重偏移。

我的绘制代码如下所示：

        canvas.save();
        canvas.translate(0, pagePosition);
        staticLayout.draw(canvas);
        canvas.restore();

其中pagePosition是一个简单的ps计数器，通过测量staticLayout.getHeight（）的结果来驱动;

要明确的是，在相当复杂的文本，线条图和图像混合上没有缺陷的情况下布局很明显，只是得到了这种依赖于设备的缺陷。

虫子还是我的大脑？

编辑：左边是Nexus，右边是S6

生产代码：

 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);
}
}

Answer 1

解决方法：

    currentPage = super.startPage(pageInfo);
    Canvas canvas = currentPage.getCanvas();
    canvas.translate(CM, CM*2);
    canvas.clipRect(0, 0, rect.width(), rect.height());

将画布保持完全相同的状态。