/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.print.pdf;
import android.annotation.IntRange;
import android.annotation.NonNull;
import android.content.Context;
import android.graphics.Rect;
import android.graphics.pdf.PdfDocument;
import android.print.PrintAttributes;
import android.print.PrintAttributes.Margins;
import android.print.PrintAttributes.MediaSize;
This class is a helper for creating a PDF file for given print attributes. It is useful for
implementing printing via the native Android graphics APIs.
This class computes the page width, page height, and content rectangle from the provided print attributes and these precomputed values can be accessed via getPageWidth(), getPageHeight(), and getPageContentRect(), respectively. The startPage(int) methods creates pages whose PageInfo is initialized with the precomputed values for width, height, and content rectangle.
A typical use of the APIs looks like this:
// open a new document
PrintedPdfDocument document = new PrintedPdfDocument(context,
printAttributes);
// start a page
Page page = document.startPage(0);
// draw something on the page
View content = getContentView();
content.draw(page.getCanvas());
// finish the page
document.finishPage(page);
. . .
// add more pages
. . .
// write the document content
document.writeTo(getOutputStream());
//close the document
document.close();
/**
* This class is a helper for creating a PDF file for given print attributes. It is useful for
* implementing printing via the native Android graphics APIs.
* <p>
* This class computes the page width, page height, and content rectangle from the provided print
* attributes and these precomputed values can be accessed via {@link #getPageWidth()},
* {@link #getPageHeight()}, and {@link #getPageContentRect()}, respectively. The
* {@link #startPage(int)} methods creates pages whose
* {@link android.graphics.pdf.PdfDocument.PageInfo PageInfo} is initialized with the precomputed
* values for width, height, and content rectangle.
* <p>
* A typical use of the APIs looks like this:
* </p>
* <pre>
* // open a new document
* PrintedPdfDocument document = new PrintedPdfDocument(context,
* printAttributes);
*
* // start a page
* Page page = document.startPage(0);
*
* // draw something on the page
* View content = getContentView();
* content.draw(page.getCanvas());
*
* // finish the page
* document.finishPage(page);
* . . .
* // add more pages
* . . .
* // write the document content
* document.writeTo(getOutputStream());
*
* //close the document
* document.close();
* </pre>
*/
public class PrintedPdfDocument extends PdfDocument {
private static final int MILS_PER_INCH = 1000;
private static final int POINTS_IN_INCH = 72;
private final int mPageWidth;
private final int mPageHeight;
private final Rect mContentRect;
Creates a new document.
Note: You must close the document after you are done by calling PdfDocument.close().
Params: - context – Context instance for accessing resources.
- attributes – The print attributes.
/**
* Creates a new document.
* <p>
* <strong>Note:</strong> You must close the document after you are
* done by calling {@link #close()}.
* </p>
*
* @param context Context instance for accessing resources.
* @param attributes The print attributes.
*/
public PrintedPdfDocument(@NonNull Context context, @NonNull PrintAttributes attributes) {
MediaSize mediaSize = attributes.getMediaSize();
// Compute the size of the target canvas from the attributes.
mPageWidth = (int) (((float) mediaSize.getWidthMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
mPageHeight = (int) (((float) mediaSize.getHeightMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
// Compute the content size from the attributes.
Margins minMargins = attributes.getMinMargins();
final int marginLeft = (int) (((float) minMargins.getLeftMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
final int marginTop = (int) (((float) minMargins.getTopMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
final int marginRight = (int) (((float) minMargins.getRightMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
final int marginBottom = (int) (((float) minMargins.getBottomMils() / MILS_PER_INCH)
* POINTS_IN_INCH);
mContentRect = new Rect(marginLeft, marginTop, mPageWidth - marginRight,
mPageHeight - marginBottom);
}
Starts a new page. The page is created using width, height and content rectangle computed from the print attributes passed in the constructor and the given page number to create an appropriate PageInfo. After the page is created you can draw arbitrary content on the page's canvas which you can get by calling Page.getCanvas(). After you are done drawing the content you should finish the page by calling PdfDocument.finishPage(Page). After the page is finished you should no longer access the page or its canvas.
Note: Do not call this method after PdfDocument.close(). Also do not call this method if the last page returned by this method is not finished by calling PdfDocument.finishPage(Page).
Params: - pageNumber – The page number. Must be a non negative.
See Also: Returns: A blank page.
/**
* Starts a new page. The page is created using width, height and content rectangle computed
* from the print attributes passed in the constructor and the given page number to create an
* appropriate {@link android.graphics.pdf.PdfDocument.PageInfo PageInfo}.
* <p>
* After the page is created you can draw arbitrary content on the page's canvas which you can
* get by calling {@link android.graphics.pdf.PdfDocument.Page#getCanvas() Page.getCanvas()}.
* After you are done drawing the content you should finish the page by calling
* {@link #finishPage(Page)}. After the page is finished you should no longer access the page or
* its canvas.
* </p>
* <p>
* <strong>Note:</strong> Do not call this method after {@link #close()}. Also do not call this
* method if the last page returned by this method is not finished by calling
* {@link #finishPage(Page)}.
* </p>
*
* @param pageNumber The page number. Must be a non negative.
* @return A blank page.
*
* @see #finishPage(Page)
*/
public @NonNull Page startPage(@IntRange(from = 0) int pageNumber) {
PageInfo pageInfo = new PageInfo
.Builder(mPageWidth, mPageHeight, pageNumber)
.setContentRect(mContentRect)
.create();
return startPage(pageInfo);
}
Gets the page width.
Returns: The page width in PostScript points (1/72th of an inch).
/**
* Gets the page width.
*
* @return The page width in PostScript points (1/72th of an inch).
*/
public @IntRange(from = 0) int getPageWidth() {
return mPageWidth;
}
Gets the page height.
Returns: The page height in PostScript points (1/72th of an inch).
/**
* Gets the page height.
*
* @return The page height in PostScript points (1/72th of an inch).
*/
public @IntRange(from = 0) int getPageHeight() {
return mPageHeight;
}
Gets the content rectangle. This is the area of the page that
contains printed data and is relative to the page top left.
Returns: The content rectangle.
/**
* Gets the content rectangle. This is the area of the page that
* contains printed data and is relative to the page top left.
*
* @return The content rectangle.
*/
public @NonNull Rect getPageContentRect() {
return mContentRect;
}
}