WebUsb Android chooser UI

chrome/browser/ui/android/usb_chooser_android.h

+// Copyright 2016 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 CHROME_BROWSER_UI_ANDROID_USB_CHOOSER_ANDROID_H_
+#define CHROME_BROWSER_UI_ANDROID_USB_CHOOSER_ANDROID_H_
+
+#include <string>
+#include <vector>
+
+#include "base/android/scoped_java_ref.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "base/scoped_observer.h"
+#include "base/strings/string16.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "device/usb/public/interfaces/chooser_service.mojom.h"
+#include "device/usb/usb_service.h"
+#include "mojo/public/cpp/bindings/array.h"
+
+namespace content {
+class RenderFrameHost;
+class WebContents;
+}
+
+namespace device {
+class UsbDevice;
+class UsbDeviceFilter;
+}
+
+// Represents a way to ask the user to select a USB device from a list of
+// options.
+class UsbChooserAndroid : public device::UsbService::Observer,
+                          public content::WebContentsObserver {

[Reilly Grant (use Gerrit), 2016/03/04 20:53:39]

I've been told that WebContentsObservers are expensive. Instead have this object
explicitly owned by the WebUsbChooserServiceAndroid which is in turn explicitly
owned by the UsbTabHelper which will destroy it if the frame navigates.

[juncai, 2016/03/05 00:18:25]

Done.

+ public:
+  UsbChooserAndroid(
+      mojo::Array<device::usb::DeviceFilterPtr> device_filters,
+      content::RenderFrameHost* render_frame_host,
+      const device::usb::ChooserService::GetPermissionCallback& callback);
+  ~UsbChooserAndroid() override;
+
+  // device::UsbService::Observer:
+  void OnDeviceAdded(scoped_refptr<device::UsbDevice> device) override;
+  void OnDeviceRemoved(scoped_refptr<device::UsbDevice> device) override;
+
+  // content::WebContentsObserver:
+  void RenderFrameDeleted(content::RenderFrameHost* render_frame_host) override;
+
+  void Select(const std::string& guid);
+  void Cancel();
+
+  void GotUsbDeviceList(
+      const std::vector<scoped_refptr<device::UsbDevice>>& devices);
+
+  // Report the dialog's result.
+  void OnDialogFinished(JNIEnv* env,
+                        const base::android::JavaParamRef<jobject>& obj,
+                        jint event_type,
+                        const base::android::JavaParamRef<jstring>& device_id);
+
+  void ShowUsbOverviewLink(JNIEnv* env,
+                           const base::android::JavaParamRef<jobject>& obj);
+
+  static bool Register(JNIEnv* env);
+
+ private:
+  void UpdateChooserDialog() const;
+
+  void OpenUrl(const std::string& url);
+
+  content::RenderFrameHost* const render_frame_host_;
+  content::WebContents* web_contents_;
+  device::usb::ChooserService::GetPermissionCallback callback_;
+  ScopedObserver<device::UsbService, device::UsbService::Observer>
+      usb_service_observer_;
+  std::vector<device::UsbDeviceFilter> filters_;
+  std::vector<scoped_refptr<device::UsbDevice>> devices_;
+  std::vector<std::string> device_guids_;
+  std::vector<base::string16> device_names_;
+  base::android::ScopedJavaGlobalRef<jobject> java_dialog_;
+  base::WeakPtrFactory<UsbChooserAndroid> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(UsbChooserAndroid);
+};
+
+#endif  // CHROME_BROWSER_UI_ANDROID_USB_CHOOSER_ANDROID_H_