printing/printing_context.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef PRINTING_PRINTING_CONTEXT_H_
   6 #define PRINTING_PRINTING_CONTEXT_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/callback.h"
  12 #include "base/strings/string16.h"
  13 #include "printing/print_settings.h"
  14 #include "ui/gfx/native_widget_types.h"
  15
  16 namespace base {
  17 class DictionaryValue;
  18 }
  19
  20 namespace printing {
  21
  22 // An abstraction of a printer context, implemented by objects that describe the
  23 // user selected printing context. This includes the OS-dependent UI to ask the
  24 // user about the print settings. Concrete implementations directly talk to the
  25 // printer and manage the document and page breaks.
  26 class PRINTING_EXPORT PrintingContext {
  27  public:
  28   // Tri-state result for user behavior-dependent functions.
  29   enum Result {
  30     OK,
  31     CANCEL,
  32     FAILED,
  33   };
  34
  35   virtual ~PrintingContext();
  36
  37   // Callback of AskUserForSettings, used to notify the PrintJobWorker when
  38   // print settings are available.
  39   typedef base::Callback<void(Result)> PrintSettingsCallback;
  40
  41   // Asks the user what printer and format should be used to print. Updates the
  42   // context with the select device settings. The result of the call is returned
  43   // in the callback. This is necessary for Linux, which only has an
  44   // asynchronous printing API.
  45   virtual void AskUserForSettings(gfx::NativeView parent_view,
  46                                   int max_pages,
  47                                   bool has_selection,
  48                                   const PrintSettingsCallback& callback) = 0;
  49
  50   // Selects the user's default printer and format. Updates the context with the
  51   // default device settings.
  52   virtual Result UseDefaultSettings() = 0;
  53
  54   // Returns paper size to be used for PDF or Cloud Print in device units.
  55   virtual gfx::Size GetPdfPaperSizeDeviceUnits() = 0;
  56
  57   // Updates printer settings.
  58   // |external_preview| is true if pdf is going to be opened in external
  59   // preview. Used by MacOS only now to open Preview.app.
  60   virtual Result UpdatePrinterSettings(bool external_preview) = 0;
  61
  62   // Updates Print Settings. |job_settings| contains all print job
  63   // settings information. |ranges| has the new page range settings.
  64   Result UpdatePrintSettings(const base::DictionaryValue& job_settings,
  65                              const PageRanges& ranges);
  66
  67   // Initializes with predefined settings.
  68   virtual Result InitWithSettings(const PrintSettings& settings) = 0;
  69
  70   // Does platform specific setup of the printer before the printing. Signal the
  71   // printer that a document is about to be spooled.
  72   // Warning: This function enters a message loop. That may cause side effects
  73   // like IPC message processing! Some printers have side-effects on this call
  74   // like virtual printers that ask the user for the path of the saved document;
  75   // for example a PDF printer.
  76   virtual Result NewDocument(const base::string16& document_name) = 0;
  77
  78   // Starts a new page.
  79   virtual Result NewPage() = 0;
  80
  81   // Closes the printed page.
  82   virtual Result PageDone() = 0;
  83
  84   // Closes the printing job. After this call the object is ready to start a new
  85   // document.
  86   virtual Result DocumentDone() = 0;
  87
  88   // Cancels printing. Can be used in a multi-threaded context. Takes effect
  89   // immediately.
  90   virtual void Cancel() = 0;
  91
  92   // Releases the native printing context.
  93   virtual void ReleaseContext() = 0;
  94
  95   // Returns the native context used to print.
  96   virtual gfx::NativeDrawingContext context() const = 0;
  97
  98   // Creates an instance of this object. Implementers of this interface should
  99   // implement this method to create an object of their implementation. The
 100   // caller owns the returned object.
 101   static PrintingContext* Create(const std::string& app_locale);
 102
 103   void set_margin_type(MarginType type);
 104
 105   const PrintSettings& settings() const {
 106     return settings_;
 107   }
 108
 109  protected:
 110   explicit PrintingContext(const std::string& app_locale);
 111
 112   // Reinitializes the settings for object reuse.
 113   void ResetSettings();
 114
 115   // Does bookkeeping when an error occurs.
 116   PrintingContext::Result OnError();
 117
 118   // Complete print context settings.
 119   PrintSettings settings_;
 120
 121   // The dialog box has been dismissed.
 122   volatile bool dialog_box_dismissed_;
 123
 124   // Is a print job being done.
 125   volatile bool in_print_job_;
 126
 127   // Did the user cancel the print job.
 128   volatile bool abort_printing_;
 129
 130   // The application locale.
 131   std::string app_locale_;
 132
 133  private:
 134   DISALLOW_COPY_AND_ASSIGN(PrintingContext);
 135 };
 136
 137 }  // namespace printing
 138
 139 #endif  // PRINTING_PRINTING_CONTEXT_H_