几个月之前，接触Android recovery源代码的时候，看ScreenRecoveryUI类的时候，那时候C++基础还不是特别好，一直不明白以下的初始化方式：
下面这个是Recovery的一个构造函数，代码位于：screen_ui.cpp，它的类的实现在screen_ui.h。
如下这个ScreenRecoveryUI类，这个类是继承于RecoveryUI类的：
这个文件在screen_ui.h
class ScreenRecoveryUI : public RecoveryUI {
public:
ScreenRecoveryUI();
void Init();
void SetLocale(const char* locale);
// overall recovery state ("background image")
void SetBackground(Icon icon);
// progress indicator
void SetProgressType(ProgressType type);
void ShowProgress(float portion, float seconds);
void SetProgress(float fraction);
void SetStage(int current, int max);
// text log
void ShowText(bool visible);
bool IsTextVisible();
bool WasTextEverVisible();
// printing messages
void Print(const char* fmt, ...) __printflike(2, 3);
void ShowFile(const char* filename);
// menu display
void StartMenu(const char* const * headers, const char* const * items,
int initial_selection);
int SelectMenu(int sel);
void EndMenu();
void KeyLongPress(int);
void Redraw();
enum UIElement {
HEADER, MENU, MENU_SEL_BG, MENU_SEL_BG_ACTIVE, MENU_SEL_FG, LOG, TEXT_FILL, INFO
};
void SetColor(UIElement e);
private:
Icon currentIcon;
int installingFrame;
const char* locale;
bool rtl_locale;
pthread_mutex_t updateMutex;
GRSurface* backgroundIcon[5];
GRSurface* backgroundText[5];
GRSurface** installation;
GRSurface* progressBarEmpty;
GRSurface* progressBarFill;
GRSurface* stageMarkerEmpty;
GRSurface* stageMarkerFill;
ProgressType progressBarType;
float progressScopeStart, progressScopeSize, progress;
double progressScopeTime, progressScopeDuration;
// true when both graphics pages are the same (except for the progress bar).
bool pagesIdentical;
size_t text_cols_, text_rows_;
// Log text overlay, displayed when a magic key is pressed.
char** text_;
size_t text_col_, text_row_, text_top_;
bool show_text;
bool show_text_ever; // has show_text ever been true?
char** menu_;
const char* const* menu_headers_;
bool show_menu;
int menu_items, menu_sel;
// An alternate text screen, swapped with 'text_' when we're viewing a log file.
char** file_viewer_text_;
pthread_t progress_thread_;
int animation_fps;
int installing_frames;
int iconX, iconY;
int stage, max_stage;
void draw_background_locked(Icon icon);
void draw_progress_locked();
void draw_screen_locked();
void update_screen_locked();
void update_progress_locked();
static void* ProgressThreadStartRoutine(void* data);
void ProgressThreadLoop();
void ShowFile(FILE*);
void PutChar(char);
void ClearText();
void DrawHorizontalRule(int* y);
void DrawTextLine(int* y, const char* line, bool bold);
void DrawTextLines(int* y, const char* const* lines);
void LoadBitmap(const char* filename, GRSurface** surface);
void LoadBitmapArray(const char* filename, int* frames, GRSurface*** surface);
void LoadLocalizedBitmap(const char* filename, GRSurface** surface);
};
