ui/gfx/android/java_bitmap.h

   1 // Copyright (c) 2012 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 UI_GFX_ANDROID_JAVA_BITMAP_H_
   6 #define UI_GFX_ANDROID_JAVA_BITMAP_H_
   7
   8 #include <jni.h>
   9
  10 #include "base/android/scoped_java_ref.h"
  11 #include "third_party/skia/include/core/SkBitmap.h"
  12 #include "ui/gfx/size.h"
  13
  14 namespace gfx {
  15
  16 // A Java counterpart will be generated for this enum.
  17 // GENERATED_JAVA_ENUM_PACKAGE: org.chromium.ui.gfx
  18 enum BitmapFormat {
  19   BITMAP_FORMAT_NO_CONFIG,
  20   BITMAP_FORMAT_ALPHA_8,
  21   BITMAP_FORMAT_ARGB_4444,
  22   BITMAP_FORMAT_ARGB_8888,
  23   BITMAP_FORMAT_RGB_565,
  24 };
  25
  26 // This class wraps a JNI AndroidBitmap object to make it easier to use. It
  27 // handles locking and unlocking of the underlying pixels, along with wrapping
  28 // various JNI methods.
  29 class GFX_EXPORT JavaBitmap {
  30  public:
  31   explicit JavaBitmap(jobject bitmap);
  32   ~JavaBitmap();
  33
  34   inline void* pixels() { return pixels_; }
  35   inline const void* pixels() const { return pixels_; }
  36   inline const gfx::Size& size() const { return size_; }
  37   // Formats are in android/bitmap.h; e.g. ANDROID_BITMAP_FORMAT_RGBA_8888
  38   inline int format() const { return format_; }
  39   inline uint32_t stride() const { return stride_; }
  40
  41   // Registers methods with JNI and returns true if succeeded.
  42   static bool RegisterJavaBitmap(JNIEnv* env);
  43
  44  private:
  45   jobject bitmap_;
  46   void* pixels_;
  47   gfx::Size size_;
  48   int format_;
  49   uint32_t stride_;
  50
  51   DISALLOW_COPY_AND_ASSIGN(JavaBitmap);
  52 };
  53
  54 // Allocates a Java-backed bitmap (android.graphics.Bitmap) with the given
  55 // (non-empty!) size and color type.
  56 GFX_EXPORT base::android::ScopedJavaLocalRef<jobject> CreateJavaBitmap(
  57     int width,
  58     int height,
  59     SkColorType color_type);
  60
  61 // Loads an SkBitmap from the provided drawable resource identifier (e.g.,
  62 // android:drawable/overscroll_glow). If the resource loads successfully, it
  63 // will be integrally scaled down, preserving aspect ratio, to a size no smaller
  64 // than |size|. Otherwise, an empty bitmap is returned.
  65 GFX_EXPORT SkBitmap
  66     CreateSkBitmapFromAndroidResource(const char* name, gfx::Size size);
  67
  68 // Converts |skbitmap| to a Java-backed bitmap (android.graphics.Bitmap).
  69 // Note: |skbitmap| is assumed to be non-null, non-empty and one of RGBA_8888 or
  70 // RGB_565 formats.
  71 GFX_EXPORT base::android::ScopedJavaLocalRef<jobject> ConvertToJavaBitmap(
  72     const SkBitmap* skbitmap);
  73
  74 // Converts |bitmap| to an SkBitmap of the same size and format.
  75 // Note: |jbitmap| is assumed to be non-null, non-empty and of format RGBA_8888.
  76 GFX_EXPORT SkBitmap CreateSkBitmapFromJavaBitmap(const JavaBitmap& jbitmap);
  77
  78 // Returns a Skia color type value for the requested input java Bitmap.Config.
  79 GFX_EXPORT SkColorType ConvertToSkiaColorType(jobject jbitmap_config);
  80
  81 }  // namespace gfx
  82
  83 #endif  // UI_GFX_ANDROID_JAVA_BITMAP_H_