SnapshotWidget
touchgfx/widgets/SnapshotWidget.hpp
A widget that is able to make a snapshot of the area the SnapshotWidget covers into either a Bitmap or into animation storage (if this available). Once the snapshot has been taken using SnapshowWidget::makeSnapshot(), the SnapshotWidget will show the captured snapshot when it is subsequently drawn.
Inherits from: Widget, Drawable
Public Functions
| virtual void | draw(const Rect & invalidatedArea) const |
| Draw this drawable. | |
| uint8_t | getAlpha() const |
| Gets the current alpha value of the widget. | |
| virtual Rect | getSolidRect() const |
| Get (the largest possible) rectangle that is guaranteed to be solid (opaque). | |
| virtual void | invalidateContent() const |
| Tell the framework that the contents of the Drawable needs to be redrawn. | |
| virtual void | makeSnapshot() |
| Makes a snapshot of the area the SnapshotWidget currently covers. | |
| virtual void | makeSnapshot(const BitmapId bmp) |
| Makes a snapshot of the area the SnapshotWidget currently covers. | |
| void | setAlpha(const uint8_t newAlpha) |
| Sets the opacity (alpha value). | |
| SnapshotWidget() | |
Protected Attributes
| uint8_t | alpha |
| The alpha with which to draw this snapshot. | |
| BitmapId | bitmapId |
| BitmapId where copy is stored s copied to. | |
Additional inherited members
Public Functions inherited from Widget
| virtual void | getLastChild(int16_t , int16_t , Drawable ** last) |
| Since a Widget is only one Drawable, Widget::getLastChild simply yields itself as result, but only if the Widget isVisible and isTouchable. | |
Public Functions inherited from Drawable
| void | center() |
| Centers the Drawable inside its parent. | |
| void | centerX() |
| Center the Drawable horizontally inside its parent. | |
| void | centerY() |
| Center the Drawable vertically inside its parent. | |
| virtual void | childGeometryChanged() |
| This function can be called on parent nodes to signal that the size or position of one or more of its children has changed. | |
| Drawable() | |
| Initializes a new instance of the Drawable class. | |
| void | drawToDynamicBitmap(BitmapId id) |
| Render the Drawable object into a dynamic bitmap. | |
| void | expand(int margin =0) |
| Expands the Drawable to have the same size as its parent with a given margin around the edge. | |
| Rect | getAbsoluteRect() const |
| Helper function for obtaining the rectangle this Drawable covers, expressed in absolute coordinates. | |
| virtual Drawable * | getFirstChild() |
| Function for obtaining the first child of this drawable if any. | |
| int16_t | getHeight() const |
| Gets the height of this Drawable. | |
| virtual void | getLastChild(int16_t x, int16_t y, Drawable ** last) =0 |
| Function for obtaining the the last child of this drawable that intersects with the specified point. | |
| Drawable * | getNextSibling() |
| Gets the next sibling node. | |
| Drawable * | getParent() const |
| Returns the parent node. | |
| const Rect & | getRect() const |
| Gets the rectangle this Drawable covers, in coordinates relative to its parent. | |
| virtual Rect | getSolidRectAbsolute() |
| Helper function for obtaining the largest solid rect (as implemented by getSolidRect()) expressed in absolute coordinates. | |
| virtual void | getVisibleRect(Rect & rect) const |
| Function for finding the visible part of this drawable. | |
| int16_t | getWidth() const |
| Gets the width of this Drawable. | |
| int16_t | getX() const |
| Gets the x coordinate of this Drawable, relative to its parent. | |
| int16_t | getY() const |
| Gets the y coordinate of this Drawable, relative to its parent. | |
| virtual void | handleClickEvent(const ClickEvent & event) |
| Defines the event handler interface for ClickEvents. | |
| virtual void | handleDragEvent(const DragEvent & event) |
| Defines the event handler interface for DragEvents. | |
| virtual void | handleGestureEvent(const GestureEvent & event) |
| Defines the event handler interface for GestureEvents. | |
| virtual void | handleTickEvent() |
| Called periodically by the framework if the Drawable instance has subscribed to timer ticks. | |
| virtual void | invalidate() const |
| Tell the framework that this entire Drawable needs to be redrawn. | |
| virtual void | invalidateRect(Rect & invalidatedArea) const |
| Request that a region of this drawable is redrawn. | |
| bool | isTouchable() const |
| Gets whether this Drawable receives touch events or not. | |
| bool | isVisible() const |
| Gets whether this Drawable is visible. | |
| virtual void | moveRelative(int16_t x, int16_t y) |
| Moves the drawable. | |
| virtual void | moveTo(int16_t x, int16_t y) |
| Moves the drawable. | |
| virtual void | setHeight(int16_t height) |
| Sets the height of this drawable. | |
| void | setPosition(const Drawable & drawable) |
| Sets the position of the Drawable to the same as the given Drawable. | |
| void | setPosition(int16_t x, int16_t y, int16_t width, int16_t height) |
| Sets the size and position of this Drawable, relative to its parent. | |
| void | setTouchable(bool touch) |
| Controls whether this Drawable receives touch events or not. | |
| void | setVisible(bool vis) |
| Controls whether this Drawable should be visible. | |
| virtual void | setWidth(int16_t width) |
| Sets the width of this drawable. | |
| void | setWidthHeight(const Bitmap & bitmap) |
| Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates). | |
| void | setWidthHeight(const Drawable & drawable) |
| Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates). | |
| void | setWidthHeight(const Rect & other) |
| Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates). | |
| void | setWidthHeight(int16_t width, int16_t height) |
| Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates). | |
| virtual void | setX(int16_t x) |
| Sets the x coordinate of this Drawable, relative to its parent. | |
| void | setXY(const Drawable & drawable) |
| Sets the x and y coordinates of this Drawable. | |
| void | setXY(int16_t x, int16_t y) |
| Sets the x and y coordinates of this Drawable, relative to its parent. | |
| virtual void | setY(int16_t y) |
| Sets the y coordinate of this Drawable, relative to its parent. | |
| virtual void | translateRectToAbsolute(Rect & r) const |
| Helper function for converting a region of this Drawable to absolute coordinates. | |
| virtual | ~Drawable() |
| Finalizes an instance of the Drawable class. | |
Protected Attributes inherited from Drawable
| Drawable * | nextSibling |
| Pointer to the next Drawable. | |
| Drawable * | parent |
| Pointer to this drawable's parent. | |
| Rect | rect |
| The coordinates of this Drawable, relative to its parent. | |
| bool | touchable |
| True if this drawable should receive touch events. | |
| bool | visible |
| True if this drawable should be drawn. | |
Public Functions Documentation
draw
Draw this drawable.
It is a requirement that the draw implementation does not draw outside the region specified by invalidatedArea.
| invalidatedArea | The sub-region of this drawable that needs to be redrawn, expressed in coordinates relative to its parent (e.g. for a complete redraw, invalidatedArea will be (0, 0, width, height). |
Reimplements: touchgfx::Drawable::draw
getAlpha
| uint8_t getAlpha | ( | ) | const |
Gets the current alpha value of the widget.
The alpha value is in range 255 (solid) to 0 (invisible).
The current alpha value.
getSolidRect
| virtual Rect getSolidRect | ( | ) | const |
Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
This information is important, as any Drawable underneath the solid area does not need to be drawn.
The solid rectangle part of the Drawable.
Note
The rectangle returned must be relative to upper left corner of the Drawable, meaning that a completely solid widget should return the full size Rect(0, 0, getWidth(), getHeight()). If no area can be guaranteed to be solid, an empty Rect must be returned. Failing to return the correct rectangle may result in errors on the display.
Reimplements: touchgfx::Drawable::getSolidRect
invalidateContent
| virtual void invalidateContent | ( | ) | const |
Tell the framework that the contents of the Drawable needs to be redrawn.
If the Drawable is invisible, nothing happens. Subclasses of Drawable are encouraged to implement this function and invalidate as little as possible, i.e. the smallest rectangle covering the visual element(s) drawn by the widget.
Reimplements: touchgfx::Drawable::invalidateContent
makeSnapshot
| virtual void makeSnapshot | ( | ) |
Makes a snapshot of the area the SnapshotWidget currently covers.
This area is defined by setting the dimensions and the position of the SnapshotWidget. The snapshot is stored in Animation Storage.
makeSnapshot
| virtual void makeSnapshot | ( | const BitmapId | bmp | ) | |
Makes a snapshot of the area the SnapshotWidget currently covers.
This area is defined by setting the dimensions and the position of the SnapshotWidget. The snapshot is stored in the provided dynamic bitmap. The format of the Bitmap must match the format of the display.
| bmp | The target dynamic bitmap. |
setAlpha
| void setAlpha | ( | const uint8_t | newAlpha | ) | |
Sets the opacity (alpha value).
This can be used to fade it away by gradually decreasing the alpha value from 255 (solid) to 0 (invisible).
| newAlpha | The new alpha value. 255=solid, 0=invisible. |
Note
The user code must call invalidate() in order to update the display.
SnapshotWidget
Protected Attributes Documentation
alpha
uint8_t alpha
The alpha with which to draw this snapshot.
bitmapId
BitmapId bitmapId
BitmapId where copy is stored s copied to.