For some applications, such as drawing apps, page layout apps and other apps that focus on graphic output, creating beautiful printed pages is a key feature. In this case, it is not enough to print an image or an HTML document. The print output for these types of applications requires precise control of everything that goes into a page, including fonts, text flow, page breaks, headers, footers, and graphic elements. Show
Creating print output that is completely customized for your application requires more programming investment than the previously discussed approaches. You must build components that communicate with the print framework, adjust to printer settings, draw page elements and manage printing on multiple pages. This lesson shows you how you connect with the print manager, create a print adapter and build content for printing. Connect to the print managerWhen your application
manages the printing process directly, the first step after receiving a print request from your user is to connect to the Android print framework and obtain an instance of the
The example code above demonstrates how to name a print job and set an instance of the Note: The last parameter in the Create a print adapterA print adapter interacts with the Android print framework and handles the steps of the printing process. This process requires users to select printers and print options before creating a document for printing. These selections can influence the final output as the user chooses printers with different output capabilities, different page sizes, or different page orientations. As these selections are made, the print framework asks your adapter to lay out and generate a print document, in preparation for final output. Once a user taps the print button, the framework takes the final print document and passes it to a print provider for output. During the printing process, users can choose to cancel the print action, so your print adapter must also listen for and react to a cancellation requests. The
The following sections describe how to implement the layout and write methods, which are critical to the functioning of a print adapter. Note: These adapter methods are
called on the main thread of your application. If you expect the execution of these methods in your implementation to take a significant amount of time, implement them to execute within a separate thread. For example, you can encapsulate the layout or print document writing work in separate Compute print document infoWithin an implementation of the
The execution of Note: The boolean parameter of the The main work of
Write a print document fileWhen it is time to write print output to a file, the Android print framework calls the Note: The Android print framework may call the Note: The boolean parameter of the The following sample
demonstrates the basic mechanics of this process using the
This sample delegates rendering of PDF page content to As with layout, execution of Note: Rendering a document for printing can be a resource-intensive operation. In order to avoid blocking the main user interface thread of your application, you should consider performing the page rendering and writing operations on a separate thread, for example in an Drawing PDF page contentWhen your application prints, your application must generate a PDF document and pass it to the Android print framework for printing. You can use any PDF generation library for this purpose. This lesson shows how to use the The
When using
Tip: While the Which of the following devices commonly use an ARM based processor?Arm processors are used extensively in consumer electronic devices such as smartphones, tablets, wearables and other mobile devices.
Which of the following technologies is commonly used to inventory the organization's equipment by attaching a tag to the device containing a chip prog?The use of RFID for inventory management requires a scanner that uses radio waves to communicate with an RFID tag. The tag itself contains a microchip that allows the reader to read data and also write data to the tag for real-time updating in place.
Which of the following ports are used by the NetBIOS protocol to share files and printers on a Windows network?Port 139 is used by SMB dialects that communicate over NetBIOS. It operates as an application layer network protocol for device communication in Windows operating systems over a network. For example, printers and serials ports communicate via Port 139.
Which type of cloud service provides users with an end to end application solution for a recurring monthly or yearly fee?Software as a service (SaaS) is a software distribution model in which a cloud provider hosts applications and makes them available to end users over the internet.
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