Prompt for granting permission to access USB devices.

extensions/browser/api/device_permissions_prompt.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSIONS_BROWSER_DEVICE_PERMISSIONS_PROMPT_H_
+#define EXTENSIONS_BROWSER_DEVICE_PERMISSIONS_PROMPT_H_
+
+#include <vector>
+
+#include "base/callback.h"
+#include "base/logging.h"
+#include "base/memory/ref_counted.h"
+#include "base/strings/string16.h"
+
+namespace content {
+class BrowserContext;
+class WebContents;
+}
+
+namespace device {
+class UsbDevice;
+class UsbDeviceFilter;
+}
+
+namespace extensions {
+
+class Extension;
+
+// Platform-independent interface for displaing a UI for choosing devices
+// (similar to choosing files).
+class DevicePermissionsPrompt {
+ public:
+  // Context information available to the UI implementation.
+  class Prompt : public base::RefCountedThreadSafe<Prompt> {
+   public:
+    // Displayed properties of a device.
+    struct DeviceInfo {
+      DeviceInfo(scoped_refptr<device::UsbDevice> device,
+                 const base::string16& name,
+                 const base::string16& serial_number,
+                 const base::string16& tooltip);
+      ~DeviceInfo();
+
+      scoped_refptr<device::UsbDevice> device;
+      base::string16 name;
+      base::string16 serial_number;
+      base::string16 tooltip;
+    };
+
+    // Since the set of devices can change while the UI is visible an
+    // implementation should register an observer.
+    class Observer {
+     public:
+      virtual void OnDevicesChanged() = 0;
+    };
+
+    Prompt();
+
+    // Only one observer may be registered at a time.
+    void SetObserver(Observer* observer);
+
+    base::string16 GetHeading() const;
+    base::string16 GetPromptMessage() const;
+    size_t GetDeviceCount() const { return devices_.size(); }
+    scoped_refptr<device::UsbDevice> GetDevice(size_t index) const;
+    base::string16 GetDeviceName(size_t index) const {
+      DCHECK_LT(index, devices_.size());
+      return devices_[index].name;
+    }
+    base::string16 GetDeviceSerialNumber(size_t index) const {
+      DCHECK_LT(index, devices_.size());
+      return devices_[index].serial_number;
+    }
+    base::string16 GetDeviceTooltip(size_t index) const {
+      DCHECK_LT(index, devices_.size());
+      return devices_[index].tooltip;
+    }
+
+    // Notifies the DevicePermissionsManager for the current extension that
+    // access to the device at the given index is now granted.
+    void GrantDevicePermission(size_t index) const;
+
+    const extensions::Extension* extension() const { return extension_; }
+    void set_extension(const extensions::Extension* extension) {
+      extension_ = extension;
+    }
+
+    void set_browser_context(content::BrowserContext* context) {
+      browser_context_ = context;
+    }
+
+    bool multiple() const { return multiple_; }
+    void set_multiple(bool multiple) { multiple_ = multiple; }
+
+    const std::vector<device::UsbDeviceFilter>& filters() const {
+      return filters_;
+    }
+    void set_filters(const std::vector<device::UsbDeviceFilter>& filters);
+
+   private:
+    friend class base::RefCountedThreadSafe<Prompt>;
+
+    virtual ~Prompt();
+
+    // Querying for devices must be done asynchronously on the FILE thread.
+    void DoDeviceQuery();
+    void SetDevices(const std::vector<DeviceInfo>& devices);
+
+    const extensions::Extension* extension_;
+    content::BrowserContext* browser_context_;
+    bool multiple_;
+    std::vector<device::UsbDeviceFilter> filters_;
+    std::vector<DeviceInfo> devices_;
+    Observer* observer_;
+  };
+
+  class Delegate {
+   public:
+    // Called with the list of selected USB devices.
+    virtual void OnUsbDevicesChosen(
+        const std::vector<scoped_refptr<device::UsbDevice>>& devices) = 0;
+
+   protected:
+    virtual ~Delegate() {}
+  };
+
+  typedef base::Callback<void(content::WebContents*,
+                              DevicePermissionsPrompt::Delegate*,
+                              scoped_refptr<DevicePermissionsPrompt::Prompt>)>
+      ShowDialogCallback;
+
+  static ShowDialogCallback GetDefaultShowDialogCallback();
+
+  DevicePermissionsPrompt(content::WebContents* web_contents);
+  virtual ~DevicePermissionsPrompt();
+
+  virtual void AskForUsbDevices(
+      Delegate* delegate,
+      const Extension* extension,
+      content::BrowserContext* context,
+      bool multiple,
+      const std::vector<device::UsbDeviceFilter>& filters);
+
+ private:
+  // Parent web contents of the device permissions UI dialog.
+  content::WebContents* web_contents_;
+
+  // The delegate called after the UI has been dismissed.
+  Delegate* delegate_;
+
+  // Parameters available to the UI implementation.
+  scoped_refptr<Prompt> prompt_;
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_API_DEVICE_PERMISSIONS_PROMPT_H_