diff --git a/docs/changes.md b/docs/changes.md
index 39df937d2..f999e0c62 100644
--- a/docs/changes.md
+++ b/docs/changes.md
@@ -1,20 +1,21 @@
 # 最新动态
 
 2024/11/28
-  * 增加函数 bitmap_set_dirty/bitmap_is_dirty
+  * 增加函数 bitmap\_set\_dirty/bitmap\_is\_dirty
+  * 重构bitmap，用bitmap\_init\_ex 实现bitmap\_create\_ex
 
 2024/11/26
-  * 增加tab_button_group删除tab_button和对应page的函数(感谢智明提供补丁)
+  * 增加tab\_button\_group删除tab\_button和对应page的函数(感谢智明提供补丁)
 
 2024/11/22
   * 修复 mledit编译警告(感谢泽武提供补丁)
 
 2024/11/21
-  * 完善conf_json(感谢兆坤提供补丁)
+  * 完善conf\_json(感谢兆坤提供补丁)
 
 2024/11/19
-  * 增加函数 str_append_format_padding
-  * 增加 atomic_compare_exchange(感谢兆坤提供补丁)
+  * 增加函数 str\_append\_format\_padding
+  * 增加 atomic\_compare\_exchange(感谢兆坤提供补丁)
   * 完善 atomic(感谢兆坤提供补丁)
 
 2024/11/18
@@ -23,7 +24,7 @@
   * fix memory error whene change theme.
 
 2024/11/17
-  * 完善 TK_STRINGIZE(感谢兆坤提供补丁)
+  * 完善 TK\_STRINGIZE(感谢兆坤提供补丁)
   * value完善调试log(感谢兆坤提供补丁)
   * 修复拼写错误(感谢兆坤提供补丁)
   * 增加原子操作(感谢兆坤提供补丁)
@@ -31,8 +32,8 @@
 2024/11/15
   * 修复拼写错误(感谢兆坤提供补丁)
   * 修复 demoui dialog(感谢兆坤提供补丁)
-  * 增加tk_strs_bsearch
-  * 修复text_selector测试用例报错问题(感谢颖健提供补丁)
+  * 增加tk\_strs\_bsearch
+  * 修复text\_selector测试用例报错问题(感谢颖健提供补丁)
   * 修复控件有offset时更新指针icon没更新的问题(感谢颖健提供补丁)
 
 2024/11/14
diff --git a/src/base/bitmap.c b/src/base/bitmap.c
index 924a498b0..a4be64ec0 100644
--- a/src/base/bitmap.c
+++ b/src/base/bitmap.c
@@ -124,41 +124,35 @@ static ret_t bitmap_web_destroy(bitmap_t* bitmap) {
   return RET_OK;
 }
 
+static ret_t bitmap_platform_create(bitmap_t* bitmap) {
+  uint32_t w = bitmap->w;
+  uint32_t h = bitmap->h;
+  uint32_t line_length = bitmap_get_physical_line_length(bitmap);
+  bitmap_format_t format = bitmap->format;
+
+  uint8_t* data = bitmap_lock_buffer_for_write(bitmap);
+  return_value_if_fail(format == BITMAP_FMT_RGBA8888, NULL);
+  int32_t id = EM_ASM_INT(
+      { return VGCanvas.createMutableImage($0, $1, $2, $3, $4); }, data, w, h, line_length, format);
+  bitmap->specific = tk_pointer_from_int(id);
+  bitmap->specific_destroy = bitmap_web_destroy;
+  bitmap_unlock_buffer(bitmap);
+
+  return RET_OK;
+}
+#else
+static ret_t bitmap_platform_create(bitmap_t* bitmap) {
+  return RET_OK;
+}
 #endif /*AWTK_WEB*/
 
 bitmap_t* bitmap_create_ex(uint32_t w, uint32_t h, uint32_t line_length, bitmap_format_t format) {
   bitmap_t* bitmap = TKMEM_ZALLOC(bitmap_t);
-  uint32_t bpp = bitmap_get_bpp_of_format(format);
-
   return_value_if_fail(bitmap != NULL, NULL);
-
-  bitmap->w = w;
-  bitmap->h = h;
-  bitmap->format = format;
+  
+  bitmap_init_ex(bitmap, w, h, line_length, format, NULL);
   bitmap->should_free_handle = TRUE;
 
-  if (bpp < 4) {
-    bitmap->flags = BITMAP_FLAG_OPAQUE;
-  }
-
-  bitmap_set_line_length(bitmap, line_length);
-
-  bitmap_alloc_data(bitmap);
-  if (bitmap->buffer == NULL) {
-    TKMEM_FREE(bitmap);
-    bitmap = NULL;
-  } else {
-#ifdef AWTK_WEB
-    uint8_t* data = bitmap_lock_buffer_for_write(bitmap);
-    return_value_if_fail(format == BITMAP_FMT_RGBA8888, NULL);
-    int32_t id = EM_ASM_INT({ return VGCanvas.createMutableImage($0, $1, $2, $3, $4); }, data, w, h,
-                            line_length, format);
-    bitmap->specific = tk_pointer_from_int(id);
-    bitmap->specific_destroy = bitmap_web_destroy;
-    bitmap_unlock_buffer(bitmap);
-#endif /*AWTK_WEB*/
-  }
-
   return bitmap;
 }
 
@@ -587,6 +581,7 @@ ret_t bitmap_init(bitmap_t* bitmap, uint32_t w, uint32_t h, bitmap_format_t form
     uint32_t bpp = bitmap_get_bpp_of_format(format);
     line_length = tk_max(w * bpp, line_length);
   }
+
   return bitmap_init_ex(bitmap, w, h, line_length, format, data);
 }
 
@@ -612,6 +607,10 @@ ret_t bitmap_init_ex(bitmap_t* bitmap, uint32_t w, uint32_t h, uint32_t line_len
     bitmap->should_free_data = TRUE;
   }
 
+  if (bitmap->buffer == NULL) {
+    bitmap_platform_create(bitmap);
+  }
+  
   return bitmap->buffer != NULL ? RET_OK : RET_OOM;
 }
 
diff --git a/tests/bitmap_test.cc b/tests/bitmap_test.cc
index e1d924ecb..44b46e3b8 100644
--- a/tests/bitmap_test.cc
+++ b/tests/bitmap_test.cc
@@ -2,7 +2,7 @@
 #include "base/bitmap.h"
 #include "gtest/gtest.h"
 
-TEST(Bitmap, basic) {
+TEST(Bitmap, basic1) {
   uint32_t n = 100;
   uint32_t i = 0;
   for (i = 0; i < n; i++) {
@@ -10,10 +10,10 @@ TEST(Bitmap, basic) {
     uint8_t* bdata = bitmap_lock_buffer_for_write(b);
     ASSERT_EQ(((intptr_t)(bdata)) % BITMAP_ALIGN_SIZE, (intptr_t)0);
     ASSERT_EQ(bitmap_get_line_length(b), b->w * 4u);
-    ASSERT_EQ(bitmap_is_dirty(b), TRUE);
-    bitmap_unlock_buffer(b);
     ASSERT_EQ(bitmap_is_dirty(b), FALSE);
-
+    bitmap_unlock_buffer(b);
+    ASSERT_EQ(bitmap_is_dirty(b), TRUE);
+    ASSERT_EQ(b->should_free_handle, TRUE);
     bitmap_destroy(b);
   }
 
@@ -23,10 +23,38 @@ TEST(Bitmap, basic) {
     ASSERT_EQ(((intptr_t)(bdata)) % BITMAP_ALIGN_SIZE, (intptr_t)0);
     ASSERT_EQ(bitmap_get_line_length(b), b->w * 2u);
     bitmap_unlock_buffer(b);
+    ASSERT_EQ(b->should_free_handle, TRUE);
     bitmap_destroy(b);
   }
 }
 
+TEST(Bitmap, basic2) {
+  bitmap_t bitmap;
+  uint32_t n = 100;
+  uint32_t i = 0;
+  bitmap_t* b = &bitmap;
+
+  for (i = 0; i < n; i++) {
+    bitmap_init_ex(b, i + 1, i + 1, 0, BITMAP_FMT_BGRA8888, NULL);
+    uint8_t* bdata = bitmap_lock_buffer_for_write(b);
+    ASSERT_EQ(((intptr_t)(bdata)) % BITMAP_ALIGN_SIZE, (intptr_t)0);
+    ASSERT_EQ(bitmap_get_line_length(b), b->w * 4u);
+    ASSERT_EQ(bitmap_is_dirty(b), FALSE);
+    bitmap_unlock_buffer(b);
+    ASSERT_EQ(bitmap_is_dirty(b), TRUE);
+    ASSERT_EQ(b->should_free_handle, FALSE);
+  }
+
+  for (i = 0; i < n; i++) {
+    bitmap_init_ex(b, i + 1, i + 1, 0, BITMAP_FMT_BGR565, NULL);
+    uint8_t* bdata = bitmap_lock_buffer_for_write(b);
+    ASSERT_EQ(((intptr_t)(bdata)) % BITMAP_ALIGN_SIZE, (intptr_t)0);
+    ASSERT_EQ(bitmap_get_line_length(b), b->w * 2u);
+    bitmap_unlock_buffer(b);
+    ASSERT_EQ(b->should_free_handle, FALSE);
+  }
+}
+
 TEST(Bitmap, row_size) {
   ASSERT_EQ(TK_BITMAP_MONO_LINE_LENGTH(8), 2);
   ASSERT_EQ(TK_BITMAP_MONO_LINE_LENGTH(9), 2);