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/**
* @page evas_examples Evas Examples
*
* Here is a page with examples.
*
* @ref Example_Evas_Buffer_Simple
*
* @ref Example_Evas_Init_Shutdown
*
* @ref Example_Evas_Text
*
* @ref Example_Evas_Images
*
* @ref Example_Evas_Images_2
*
* @ref Example_Evas_Events
*
* @ref Example_Evas_Object_Manipulation
*
* @ref Example_Evas_Aspect_Hints
*
* @ref Example_Evas_Size_Hints
*
* @ref Example_Evas_Stacking
*
* @ref Example_Evas_Smart_Objects
*
* @ref Example_Evas_Box Evas box
*/
/**
* @page Example_Evas_Buffer_Simple Simple Evas canvas example
*
* The canvas will here use the buffer engine.
*
* @include evas-buffer-simple.c
* @example evas-buffer-simple.c
*/
/**
* @page Example_Evas_Init_Shutdown Evas' init/shutdown routines example
*
* @include evas-init-shutdown.c
* @example evas-init-shutdown.c
*/
/**
* @page Example_Evas_Images Some image object functions examples
* @dontinclude evas-images.c
*
* In this example, we add two images to a canvas, each one having a
* quarter of the canvas' size, positioned on the top left and bottom
* right corners, respectively:
* @skip img1 = evas_object_image_add(d.evas);
* @until ecore_main_loop_begin
* See there is a border image around the top left one, <b>which is
* the one that should be displayed</b>. The other one will (on
* purpose) fail to load, because we set a wrong file path as image
* source on it:
* @dontinclude evas-images.c
* @skip valid_path
* @until bogus_path
* This is how one is supposed to test for success when binding source
* images to image objects: evas_object_image_load_error_get(),
* followed by evas_load_error_str(), if one wants to pretty print/log
* the error. We'll talk about the border image further.
*
* To interact with the program, there's a command line interface.
* A help string can be asked for with the 'h' key:
* @dontinclude evas-images.c
* @skip commands
* @until ;
* The first four commands will change the top left images's @b fill property
* values, which dictate how the source image (Enlightenment's logo)
* is to be displayed through the image object's area. Experiment with
* those switches until you get the idea of evas_object_fill_set().
*
* The 'f' command will toggle that image's "filled" property, which
* is whether it should track its size and set the fill one to fit the
* object's boundaries perfectly (stretching). Note that this command
* and the four above it will conflict: in real usage one would use
* one or other ways of setting an image object's viewport with regard
* to its image source.
*
* There are four commands which deal with the border image. This red
* frame is there to illustrate <b>image borders</b>. The image source
* for the border is a solid red rectangle, with a transparent @b
* rectangular area in its middle. See how we use it to get a 3 pixel
* wide frame with <code>evas_object_image_border_set(d.border, 3, 3,
* 3, 3)</code>. To finish the effect of showing it as a border, we
* issue <code>evas_object_image_border_center_fill_set(d.border,
* EVAS_BORDER_FILL_NONE)</code>.
*
* Use 't' to change the border's thickness. 'b' will change the
* border image's center region rendering schema: either a hole (no
* rendering), blending (see the original transparent area, in this
* case) or solid (the transparent area gets filled). Finally, 'c'
* will change the border's scaling factor.
*
* While you have the border in 'blending mode', test the command 'm':
* it will set whether to use or not smooth scaling on the border's
* source image. Since the image is small originally (30 x 30), we're
* obviously up-scaling it (except the border pixels, do you
* remember?). With this last switch, you'll either see the
* transparent shape in the middle flat (no smoothing) or blurry
* (smoothed).
*
* The full example follows.
*
* @include evas-images.c
* @example evas-images.c
*/
/**
* @page Example_Evas_Images_2 Some more image object functions examples (2nd block)
* @dontinclude evas-images2.c
*
* In this example, we have three images on the canvas, but one of
* them is special -- we're using it as a <b>proxy image
* object</b>. It will mirror the contents of the other two images
* (which are the ones on the top of the canvas), one at a time:
* @skip d.proxy_img = evas_object_image_filled_add(d.evas);
* @until evas_object_show(d.proxy_img);
* As in other examples, we have a command line interface on it.
* @dontinclude evas-images2.c
* @skip commands
* @until ;
* The 'p' one will change the source of the proxy image to one of the
* other two, as seem above.
* @skip if (strcmp(ev->key, "p") == 0)
* @until }
* Note the top right image, the smaller one:
* @dontinclude evas-images2.c
* @skip noise_img =
* @until show
* Since we are creating the data for its pixel buffer ourselves, we
* have to set its size with evas_object_image_size_set(), first. We
* set our data with the function evas_object_image_data_set(), where
* the second argument is a buffer with random data. There's a last
* command to print it's @b stride value. Since its created with one
* quarter of the canvas's original width
* @dontinclude evas-images2.c
* @skip define WIDTH
* @until define HEIGHT
* you can check this value.
*
* The image on the top left also has a subtlety: it is @b pre-loaded
* on this example.
* @dontinclude evas-images2.c
* @skip d.logo =
* @until show
* On real use cases we wouldn't be just printing something like this
* @dontinclude evas-images2.c
* @skip static void
* @until }
* naturally.
*
* The 's' command will save one of the images on the disk, in the png
* format:
* @dontinclude evas-images2.c
* @skip if (strcmp(ev->key, "a") == 0)
* @until }
*
* The full example follows.
*
* @include evas-images2.c
* @example evas-images2.c
*/
/**
* @page Example_Evas_Events Evas events (canvas and object ones) and some canvas operations example
* @dontinclude evas-events.c
*
* In this example we illustrate how to interact with canvas' (and its
* objects') events, including the key input ones. We also demonstrate
* precise point collision on objects and canvas "obscured regions",
* here.
*
* The example application consists of a window with a white
* background and an image -- the Enlightenment logo. The application
* begins with this image switching back and forth into two sizes: the
* exact canvas' size and one quarter of it (when it's placed on the
* top left quadrant). Thus, we'll have an @b animation going on,
* with image states set to change each 2 elapsed seconds.
*
* There's a global variable to aid accessing our desired context
* variables from anywhere in the code:
* @dontinclude evas-events.c
* @skip test_data
* @until {0}
*
* What interests us there are the @c canvas pointer, our image handle
* -- @c img -- and the background one, @c bg.
*
* The first interesting thing on the example is the registration of a
* callback on each canvas resizing event, where we put our canvas'
* size and the background rectangle's one in synchrony, so that we
* don't get bogus content on rendering with canvas resizes:
* @dontinclude evas-events.c
* @skip resize_set
* @until resize_set
* @dontinclude evas-events.c
* @skip here to keep
* @until }
*
* Than, after grabbing our canvas pointer from the Ecore Evas helper
* infrastructure, we registrate an event callbacks on it:
* @skip evas_event_callback_add(d.canvas, EVAS_CALLBACK_RENDER_FLUSH_PRE,
* @until two canvas event callbacks
* @dontinclude evas-events.c
* @skip render flush callback
* @until }
* It will be called whenever our canvas has to flush its rendering
* pipeline. In this example, two ways of observing that message
* which is printed in the cited callback are:
* - to resize the example's window (thus resizing the canvas' viewport)
* - let the animation run
*
* When one resizes the canvas, there's at least one operation it has
* to do which will require new calculation for rendering: the
* resizing of the background rectangle, in a callback we already
* shown you.
*
* The creation of our background rectangle is so that we give it a @b name,
* via evas_object_name_set() and we give it the canvas @b focus:
* @dontinclude evas-events.c
* @skip bg = evas_object_rectangle_add
* @until focus_set
*
* Still exemplifying events and callbacks, we register a callback on
* the canvas event of an object being focused:
* @dontinclude evas-events.c
* @skip add(d.canvas, EVAS_CALLBACK_CANVAS_OBJECT_FOCUS
* @until }
* @dontinclude evas-events.c
* @skip called when
* @until }
*
* In that call, @c event_info is going to be the focused object's
* handle, in this case our background rectangle. We print its name,
* so you can check it's the same. We check that pointer is the same
* reported by Evas' API with regard to the newest focused
* object. Finally, we check whether that object is really flagged as
* focused, now using an Evas object API function.
*
* The animation we talked about comes from a timer we register just
* before we start the example's main loop. As we said, the resizing
* of the image will also force the canvas to repaint itself, thus
* flushing the rendering pipeline whenever the timer ticks:
* @dontinclude evas-events.c
* @skip d.resize_timer = ecore
* @until d.resize_timer = ecore
* @dontinclude evas-events.c
* @skip put some action
* @until }
* When you start this example, this animation will be
* running, by default. To interact with the program, there's a
* command line interface. A help string can be asked for with the
* 'h' key:
* @dontinclude evas-events.c
* @skip static const char *commands
* @until ;
* These are the commands the example will accept at any time, except
* when one triggers the 'f' one. This command will exemplify
* evas_event_freeze(), which interrupts @b all input events
* processing for the canvas (in the example, just for 3 seconds). Try
* to issue events for it during that freeze time:
* @dontinclude evas-events.c
* @skip if (strcmp(ev->key, "f") == 0)
* @until }
* The 'd' command will unregister those two canvas callbacks for you,
* so you won't see the messages about the focused object and the
* rendering process anymore:
* @dontinclude evas-events.c
* @skip if (strcmp(ev->key, "d") == 0)
* @until }
* In this example, we start using a focused object to handle the input
* events -- the background rectangle. We register a callback on an key input
* event occurring on it, so that we can act on each key stroke:
* @skip object_event_callback_add
* @until }
* @dontinclude evas-events.c
* @skip examine the keys pressed
* @until key grab
* We do so by examining the @c ev->key string (remember the event
* information struct for key down events is the #Evas_Event_Key_Down
* one). There's one more trick for grabbing input events on this
* example -- evas_object_key_grab(). The 'c' command will, when
* firstly used, @b unfocus the background rectangle. Unfocused
* objects on an Evas canvas will @b never receive key events. We
* grab, then, the keys we're interested at to the object forcefully:
* @skip if (d.focus)
* @until got here by key grabs
* This shows how one can handle input not depending on focus issues
* -- you can grab them globally. Switch back and forth focus and
* forced key grabbing with the 'c' key, and observe the messages
* printed about the focused object. Observe, also, that we register
* two more @b object callbacks, this time on the image object
* (Enlightenment logo), where we just print messages telling the mouse
* pointer has entered or exited it area:
* @skip evas_object_show(d.img);
* @until mouse_out, NULL
* @dontinclude evas-events.c
* @skip mouse enters the object's area
* @until mouse exits the object's area
* Experiment with moving the mouse pointer over the image, letting it
* enter and exit its area (stop the animation with 'a', for a better
* experience). When you start the example, Evas will consider this
* area by being the whole boundary rectangle around the picture. If
* you issue the 'p' command, though, you get a demonstration of Evas'
* precise point collision detection on objects. With
* evas_object_precise_is_inside_get(), one can make Evas consider the
* transparent areas of an object (the middle of the logo's E letter,
* in the case) as not belonging to it when calculating mouse
* in/out/up/down events:
* @dontinclude evas-events.c
* @skip if (strcmp(ev->key, "p") == 0)
* @until }
* To finish the example, try the command bound to Control + 'o',
* which exemplifies Evas' <b>obscured regions</b>. When firstly
* pressed, you'll get the same contents, in a region in the middle of
* the canvas, at the time the key was pressed, until you toggle the
* effect off again (make sure the animation is running on to get the
* idea better). When you toggle this effect off, we also demonstrate
* the use of evas_render_updates(), which will force immediate
* updates on the canvas rendering, bringing back the obscured
* region's contents to normal.
* @skip mods = evas_key_modifier_get(evas);
* @until end of obscured region command
*
* What follows is the complete code for this example.
*
* @include evas-events.c
* @example evas-events.c
*/
/**
* @page Example_Evas_Object_Manipulation Evas objects basic manipulation example
*
* @include evas-object-manipulation.c
* @example evas-object-manipulation.c
*/
/**
* @page Example_Evas_Aspect_Hints Evas aspect hints example
*
* @include evas-aspect-hints.c
* @example evas-aspect-hints.c
*/
/**
* @page Example_Evas_Size_Hints Evas alignment, minimum size, maximum size, padding and weight hints example
*
* In this code, we place a (vertical) box with two rectangles as
* child elements. It has a command line interface with which to act
* on those rectangles' <b>size hints</b>:
* @dontinclude evas-hints.c
* @skip static const char commands
* @until ;
*
* That should be self explanatory. Change those values (possibly
* resizing the box, which will resize together with the example's
* window) to get how size hints are honored by a container object,
* which in this case is the Evas box.
*
* More on this smart object can be found on @ref Example_Evas_Box.
* The full code for this example follows.
*
* @include evas-hints.c
* @example evas-hints.c
*/
/**
* @page Example_Evas_Box Evas box example
*
* In this example, we demonstrate the use of Evas box objects. We
* cover changing boxes' layouts (with a custom layout, besides the
* ones provided by Evas), box padding and alignment influence on the
* layouts, insertion and removal of box items.
*
* The interesting part of the code starts, naturally, when we add a
* box object to the canvas. Just after it, we place five rectangles,
* with random colors, inside of it. Those rectangles get a minimum
* size hint of 50 pixels on each axis, which will be respected by
* most of the box's possible layouts:
* @dontinclude evas-box.c
* @skip evas_object_box_add
* @until }
* @until }
*
* Just like in other Evas examples, we have a white background on the
* canvas and a red border around the container object of interest,
* the box, to mark its boundaries. Resizing of the canvas will keep
* the box's proportion with regard to the whole canvas', so that you
* can experiment with different sizes of the box to accommodate its
* children:
* @dontinclude evas-box.c
* @skip adjust canvas' contents on resizes
* @until }
*
* Again, one interacts with this program by means of key commands:
* @dontinclude evas-box.c
* @skip static const char *commands
* @until ;
*
* Let's start with the @b numeric ones, each of which will impose a
* different layout on the box object.
*
* The initial layout the box starts at is the one triggered by the
* key @c '1' -- the horizontal layout. Thus, the initial appearance
* of this program, demonstrating this layout, is something like:
*
* @image html evas-box-example-00.png
* @image rtf evas-box-example-00.png
* @image latex evas-box-example-00.eps
*
* The vertical layout (@c '2' key) is very similar, but just
* disposing the items vertically:
*
* @image html evas-box-example-01.png
* @image rtf evas-box-example-01.png
* @image latex evas-box-example-01.eps
*
* Note the influence of the (default) @c 0.5 box alignment property,
* which will let the children line in the middle of the box's
* area. Also, because the space required by them extrapolates the
* box's height (we resized it to be smaller), they'll be drawn out if
* its bounds.
*
* Next, comes the horizontal @b homogeneous layout (@c '3' key). See
* how it reserves an equal amount of space for each child to take:
*
* @image html evas-box-example-02.png
* @image rtf evas-box-example-02.png
* @image latex evas-box-example-02.eps
*
* Its vertical equivalent can be triggered by the @c '4' key. The
* next different layout of interest is the horizontal maximum size
* homogeneous (@c '5' key). It will reserve cells to children sized
* equally to the dimensions of the child with bigger size (or minimum
* size hints). For this example, all cells would be just the size of
* our rectangles' minimum size hints and, to prove that, insert a new
* (smaller) rectangle at position 3, say, with @c Ctrl and @c 3 keys
* together:
*
* @image html evas-box-example-03.png
* @image rtf evas-box-example-03.png
* @image latex evas-box-example-03.eps
*
* The code for the commands inserting and deleting box items is:
* @dontinclude evas-box.c
* @skip mods, "Shift"
* @until }
* @until }
* @dontinclude evas-box.c
* @skip new rectangle to be put in the box
* @until }
* In that code, we exemplify evas_object_box_children_get(), to fetch
* a child element at an exact position. After the element removal
* from the box (leaving it unparented again), we delete it and free
* that list. The code inserting a new rectangle, there, is
* straightforward.
*
* Try the @c '6' key for the vertical equivalent of the last shown
* layout. Then, comes the @b flow layout, triggered by the @c '7'
* key. We make our box small to demonstrate the effect on the items
* layouting:
*
* @image html evas-box-example-04.png
* @image rtf evas-box-example-04.png
* @image latex evas-box-example-04.eps
*
* The next two numerical commands are for the vertical equivalent of
* the last and the stack one, respectively. Try them out to get their
* looks.
*
* The last numerical key, @c '0', shows the effect of a @b custom
* layout on the box. We wrote one that would split the width and
* height of the box equally and, then, place the items in the cells
* in the diagonal:
* @dontinclude evas-box.c
* @skip key, "0"
* @until }
* @dontinclude evas-box.c
* @skip custom 'diagonal' layout
* @until }
* @until }
*
* @image html evas-box-example-05.png
* @image rtf evas-box-example-05.png
* @image latex evas-box-example-05.eps
*
* Finally, the @c 'a' and @c 'p' commands will change the box's
* alignment and padding property values, respectively. For each of
* the layouts above, see the effects they make by setting different
* values on those properties.
*
* The full code for this example follows. For an exercise on <b>the
* effect of children box elements' size hints on a box layout</b>,
* try the @ref Example_Evas_Size_Hints.
*
* @include evas-box.c
* @example evas-box.c
*/
/**
* @page Example_Evas_Stacking Evas object stacking functions (and some event handling)
* @dontinclude evas-stacking.c
*
* In this example, we illustrate how to stack objects in a custom
* manner and how to deal with layers.
*
* We have three objects of interest in it -- white background, red
* rectangle, green rectangle and blue rectangle.
* @skip d.bg = evas_object_rectangle_add(d.canvas);
* @until evas_object_resize(d.bg, WIDTH, HEIGHT);
* @skip d.rects[2] = evas_object_rectangle_add(d.canvas);
* @until evas_object_show(d.rects[0]);
* @dontinclude evas-stacking.c
* Like in other Evas examples, one interacts with it by means of key
* commands:
* @skip static const char *commands
* @until ;
* At any given point, like seem above, you'll be operating one rectangle only.
* You may stacking it below an adjacent object with "b":
* @skip evas_object_stack_below(d.rects[d.cur_rect], neighbour);
* @until evas_object_stack_below(d.rects[d.cur_rect], neighbour);
* @dontinclude evas-stacking.c
* "a" will do the opposite:
* @skip evas_object_stack_above(d.rects[d.cur_rect], neighbour);
* @until evas_object_stack_above(d.rects[d.cur_rect], neighbour);
* To bring it directly to the top/bottom, use "t"/"m", respectively:
* @dontinclude evas-stacking.c
* @skip evas_object_raise(d.rects[d.cur_rect]);
* @until evas_object_raise(d.rects[d.cur_rect]);
* @skip evas_object_lower(d.rects[d.cur_rect]);
* @until evas_object_lower(d.rects[d.cur_rect]);
* At any time, use the "s" command to see the status of the
* ordering. It will show the background's ordering too. Note that it
* also shows the @b layer for this object. It starts at a @b
* different layer than the others. Use "l" to change its layer
* (higher layer numbers mean higher layers). If the background is on
* the same layer as the others (0), you'll see it interact with them
* on the ordering. If it's in the layer above, no matter what you do,
* you'll see nothing but the white rectangle: it covers the other
* layers. For the initial layer (-1), it will never mess nor occlude
* the others.
*
* Let's make some tests with those commands. The rectangle which starts
* selected and which will receive our commands is the @b red one. It
* starts stacked above all the others, like seem above:
*
* @image html evas-stacking-example-00.png
* @image rtf evas-stacking-example-00.png
* @image latex evas-stacking-example-00.eps
*
* Stack it one level below, with 'b', and you'll get:
*
* @image html evas-stacking-example-01.png
* @image rtf evas-stacking-example-01.png
* @image latex evas-stacking-example-01.eps
* Note how the rectangle which laid above it, the green one, is now
* on top of it. Now change the rectangle to operate on to the blue
* one, with two consecutive 'c' commands. Note that it's the lowest
* one on the stack of rectangles. Issue the 'a' command for it, thus
* re-stacking it one level above:
*
* @image html evas-stacking-example-02.png
* @image rtf evas-stacking-example-02.png
* @image latex evas-stacking-example-02.eps
* You can send it to the top of its layer directly with the 't' command:
*
* @image html evas-stacking-example-03.png
* @image rtf evas-stacking-example-03.png
* @image latex evas-stacking-example-03.eps
* Now put it back to the bottom of that layer with 'm':
*
* @image html evas-stacking-example-04.png
* @image rtf evas-stacking-example-04.png
* @image latex evas-stacking-example-04.eps
* Like said above, we have two layers used at the beginning of the
* example: the default one (0) and the one immediately below it (-1),
* for the white background. Let's change this setup by issuing the
* 'l' command, which will change the background's layer to 1, i.e., a
* layer @b above the one holding the other rectangles:
*
* @image html evas-stacking-example-05.png
* @image rtf evas-stacking-example-05.png
* @image latex evas-stacking-example-05.eps
* See how it now covers everything else. Press 'l' again, taking it
* now to layer 0. It's still covering everything because it lands the
* layer as the highest one on the objects stack. As we have the blue
* rectangle as the one receiving stacking commands, hit 't' and
* you'll see it again:
*
* @image html evas-stacking-example-06.png
* @image rtf evas-stacking-example-06.png
* @image latex evas-stacking-example-06.eps
* By bringing the background back to layer -1 ('l'), you'll get:
*
* @image html evas-stacking-example-07.png
* @image rtf evas-stacking-example-07.png
* @image latex evas-stacking-example-07.eps
*
* The last two commands available are "p" and "r", which will make
* the target rectangle to @b pass (ignore) and @b repeat the mouse
* events occurring on it (the commands will cycle through on and off
* states). This is demonstrated with the following
* #EVAS_CALLBACK_MOUSE_DOWN callback, registered on each of the
* colored rectangles:
* @dontinclude evas-stacking.c
* @skip static void
* @until }
* Try to change these properties on the three rectangles while
* experimenting with mouse clicks on their intersection region.
*
* The full example follows.
*
* @include evas-stacking.c
* @example evas-stacking.c
*/
/**
* @page Example_Evas_Map_Overview Evas Map - Overview
* @dontinclude evas-map-utils.c
*
* Down to the very bottom, Map is simple: it takes an object and transforms
* the way it will be shown on screen. But using it properly can be a bit
* troublesome.
*
* For the most common operations there are utility functions that help in
* setting up the map to achieve the desired effects. Now we'll go through
* an overview of the map API and some of the things that can be done with
* it.
*
* The full code can be found @ref evas-map-utils.c "here".
*
* To show how some functions work, this example listens to keys pressed to
* toggle several options.
* @skip typedef
* @until App_Data
* @until ;
*
* In this program, we divide the window in four quadrants, each holding an
* object that will have different map configurations applied to them in each
* call to an animator function.
* @skip static Eina_Bool
* @until evas_output_size_get
*
* Let's first create a map and set some of our options to it. Only four
* points maps are supported, so we'll stick to that magic number. We can
* set a color for each vertex or apply one for all of them at once
* @until evas_map_util_points_color_set
*
* For the first object, we'll have a plain rectangle. At its creation, this
* rectangle was set to be semi-transparent, but whether its own alpha is
* used will be defined by the map's alpha setting. If the map's alpha is
* disabled, then the object will be completely opaque. The map's own color,
* however, will use any alpha set to it.
*
* So we get our object, initialize our map geometry to match the rectangle
* and make it rotate around its own center, then apply the map to the
* object so it takes effect.
* @until evas_object_map_enable_set
*
* The second object is an image. Here we don't have any color set for the
* object, but the image itself contains an alpha channel that will not be
* affected by the map settings, so even with alpha set to be off, the image
* will still be transparent. Color applied to the map will tint it though.
* Since setting a map copies it into the object, we can reuse the same one
* we created before. We initialize it to the new object while all other
* options are kept the same. Notice that no rotation will be done here, as
* that's just an utility function that takes the coordinates set for each
* point of the map and transforms it accordingly.
* @until evas_map_util_points_populate_from_object_full
*
* This time the object is a bit farther into the screen, by using a @c z
* value higher than 0 to init the map. We also need to map the image used
* by the object, so Evas knows how to transform it properly. For this we
* use the evas_map_point_image_uv_set() to tell the map what coordinate
* within the image corresponds to each point of the map.
* @until evas_map_point_image_uv_set(m, 3
*
* This object will also be rotated, but in all three axis and around some
* other point, not its center, chosen mostly at random. If enabled, lighting
* will be applied to, from a light source at the center of the window.
* @until evas_object_map_enable_set
*
* For the third object we are doing, once more, a 3D rotation, but this time
* perspective will be applied to our map to make it look more realistic.
* The lighting source also follows the mouse cursor and it's possible to
* toggle backface culling, so that the object is hidden whenever we are
* not seeing its front face.
* @until evas_object_map_enable_set
*
* And we free this map, since we messed too much with it and for the
* last object we want something cleaner.
* @until evas_map_free
*
* The last object is actually two. One image, with an image set to it, and
* one image proxying the first one with evas_object_image_source_set(). This
* way, the second object will show whatever content its source has.
* This time we'll be using a map more manually to simulate a simple reflection
* of the original image.
*
* We know that the reflection object is placed just like the original, so
* we take a shortcut by just getting the geometry of our to-be-mapped object.
* We also need to get the image size of the source.
* @until evas_object_image_size_get
*
* For this we'll create a map shaped so that it begins at the base of our
* image and it expands horizontally as it grows (downwards) in height.
* @until evas_map_point_coord_set(m, 3
*
* Since the reflection should show the image inverted, we need to map it
* this way. The first point of the map (top-left) will be mapped to the
* mapped to the first pixel of the last row. There's no horizontal reflection
* and we want the full width of the image, but as we map its upper side ww
* will only take two thirds of the image.
* @until evas_map_point_image_uv_set(m, 3
*
* Finally, to fade out our reflection we set the colors for each point in
* the map. The two at the top need to be visible, but we'll tone them down
* a bit and make them a bit translucent. The other two will go straight to
* full transparency. Evas interpolates the colors from one point to the next,
* so this will make them fade out.
* @until evas_object_map_enable_set
*
* Close up by freeing the map and do some other things needed to keep stuff
* moving in our animations and we are done.
* @until }
*
* The rest of the program is setup and listening to key events. Nothing that
* matters within the scope of this example, so we are going to skip it.
* Refer to it @ref evas-map-utils.c "here" however to see how everything
* fits together.
*
* @example evas-map-utils.c
*/
/**
* @page Example_Evas_Smart_Objects Evas object smart objects
* @dontinclude evas-smart-object.c
*
* In this example, we illustrate how to create and handle Evas smart objects.
*
* A smart object is one that provides custom functions to handle
* clipping, hiding, moving, resizing, color setting and more on @b
* child elements, automatically, for the smart object's user. They
* could be as simple as a group of objects that move together (see
* @ref Evas_Smart_Object_Clipped) or implementations of whole complex
* UI widgets, providing some intelligence (thus the name) and
* extension to simple Evas objects.
*
* Here, we create one as an example. What it does is to control (at
* maximum) 2 child objects, with regard to their geometries and
* colors. There can be a "left" child and a "right" one. The former
* will always occupy the top left quadrant of the smart object's
* area, while the latter will occupy the bottom right. The smart
* object will also contain an @b internal decorative border object,
* which will also be controlled by it, naturally.
*
* Here is where we add it to the canvas:
* @skip d.smt = evas_smart_example_add(d.evas);
* @until show
*
* The magic starts to happen in the @c evas_smart_example_add()
* function, which is one in the example smart object's defined @b
* interface. These should be the functions you would export to the
* users of your smart object. We made three for this one:
* - @c evas_smart_example_add(): add a new instance of the example
* smart object to a canvas
* - @c evas_smart_example_remove(): remove a given child of the smart
* object from it
* - @c evas_smart_example_set_left(): set the left child of the smart
* object
* - @c evas_smart_example_set_right(): set the right child of the
* smart object
*
* The object's creation takes place as:
* @dontinclude evas-smart-object.c
* @skip add a new example smart object to a canvas
* @until }
*
* Smart objects are defined by <b>smart classes</b>, which are structs
* defining their interfaces, or <b>smart functions</b> (see
* #Evas_Smart_Class, the base class for any smart object). As you
* see, one has to use the evas_object_smart_add() function to
* instantiate smart objects. Its second parameter is what matters --
* an #Evas_Smart struct, which contains all the smart class
* definitions (smart functions, smart callbacks, and the like). Note,
* however, that @c _evas_smart_example_smart_class_new() seems not to
* be defined in our example's code. That's because it came from a very
* handy <b>helper macro</b>:
* @dontinclude evas-smart-object.c
* @skip EVAS_SMART_SUBCLASS_NEW
* @until _smart_callbacks
* What it does is to @b subclass a given existing smart class, thus
* specializing it. This is very common and useful in Evas. There is a
* built-in smart object, the "clipped smart object", which implements
* a behavior mostly desired by many other smart object implementors:
* it will clip its children to its area and move them along with it,
* on evas_object_move() calls. Then, our example smart object will
* get that behavior for free.
*
* The first argument to the macro,
* @dontinclude evas-smart-object.c
* @skip _evas_smart_example_type
* @until _evas_smart_example_type
* will define the new smart class' name. The second tells the macro
* what is the @b prefix of the function it will be declaring with a @c
* _smart_set_user() suffix. On this function, we may override/extend
* any desired method from our parent smart class:
* @dontinclude evas-smart-object.c
* @skip setting our smart interface
* @until }
*
* The first function pointer's code will take place at an example
* smart object's @b creation time:
* @dontinclude evas-smart-object.c
* @skip create and setup
* @until }
*
* The #EVAS_SMART_DATA_ALLOC macro will take care of allocating our
* smart object data, which will be available on other contexts for us
* (mainly in our interface functions):
* @dontinclude evas-smart-object.c
* @skip typedef struct _Evas_Smart_Example_Data
* @until };
*
* See that, as we're inheriting from the clipped smart object's
* class, we @b must have their data struct as our first member. Other
* data of interest for us is a child members array and the border
* object's handle. The latter is what is created in the last
* mentioned function. Note how to tell Evas the border will be
* managed by our smart object from that time on:
* <code>evas_object_smart_member_add(priv->border, o);</code>.
* The counterpart of this function is exemplified on the smart
* object's interface function to remove children:
* @skip remove a child element
* @until set to
*
* At the end of that function we make use of an constant defined by
* the #EVAS_SMART_SUBCLASS_NEW: @c _evas_smart_example_parent_sc. It
* has the same prefix we passed to the macro, as you can see, and it
* holds a pointer to our @b parent smart class. Then, we can call the
* specialized method, itself, after our code. The @c del, @c hide, @c
* show and @c resize specializations are straightforward, we let the
* reader take a look at them below to check their behavior. What's
* interesting is the @c calculate one:
* @dontinclude evas-smart-object.c
* @skip act on child objects' properties
* @until setting
*
* This code will take place whenever the smart object itself is
* flagged "dirty", i.e., must be recalculated for rendering (that
* could come from changes on its clipper, resizing, moving,
* etc). There, we make sure the decorative border lies on the edges of
* the smart object and the children, if any, lie on their respective
* quadrants.
*
* After instantiating our smart object, we do some checks to exemplify
* some of the API on smart objects:
* @dontinclude evas-smart-object.c
* @skip ret = evas_object_smart_type_check
* @until "no"
* The evas_object_smart_type_check() one will assure we have the
* string naming our smart class really set to the live object. The
* evas_object_smart_clipped_clipper_get() exemplifies usage of
* "static clippers" -- clipped smart objects have their global
* clippers flagged static.
*
* Other important things we also exemplify here are <b>smart
* callbacks</b> and smart callback @b introspection:
* @dontinclude evas-smart-object.c
* @skip EVT_CHILDREN_NUMBER_CHANGED
* @until ;
*
* Here we declare our array of smart callback descriptions, which has
* one element only, in this case. That callback will take place, as
* the name indicates, whenever the number of member objects in our
* smart object example instance changes. That global array variable
* must be the last argument to #EVAS_SMART_SUBCLASS_NEW, so that it's
* registered as the <b>smart class</b>'s callbacks description.
*
* After we instantiate the smart object, we take a look on those
* descriptions and register a callback on that unique smart event:
* @dontinclude evas-smart-object.c
* @skip for (;
* @until focus_set
*
* The code of the callback will just print how many member objects we
* have, which is an integer argument of the callback itself, as
* flagged by its description:
* @dontinclude evas-smart-object.c
* @skip callback on number of member objects changed
* @until }
*
* One of the points at which we issue that callback is inside the @c
* evas_smart_example_remove(), code that was already shown.
*
* As in other examples, to interact with this one there's a command
* line interface. A help string can be asked for with the 'h' key:
* @dontinclude evas-smart-object.c
* @skip static const char *commands =
* @until ;
* Use 'l' and 'r' keys, to create new rectangles and place them on
* the left (@c evas_smart_example_set_left()) or right (@c
* evas_smart_example_set_right()) spots of our smart object,
* respectively. The 'w' command will remove all member objects from
* the smart object and delete them. The keyboard arrows will move the
* smart object along the canvas. See how it takes any child objects
* with it during its movement. The 'd' and 'i' keys will increase or
* decrease the smart object's size -- see how it affects the
* children's sizes, too. Finally, 'c' will change the color of the
* smart object's clipper (which is the exact internal clipper coming
* from a clipped smart object):
* @dontinclude evas-smart-object.c
* @skip d.clipper =
* @until .a);
*
* "Real life" examples of smart objects are Edje and Emotion objects:
* they both have independent libraries implementing their
* behavior. The full example follows.
*
* @include evas-smart-object.c
* @example evas-smart-object.c
*/
/**
* @page Example_Evas_Smart_Interfaces Evas object smart interfaces
* @dontinclude evas-smart-interface.c
*
* In this example, we illustrate how to create and handle Evas smart
* @b interfaces. Note that we use the same code base of the @ref
* Example_Evas_Smart_Objects example, here. We just augment it with
* an interfaces demonstration.
*
* A smart interface is just a functions interface a given smart
* object is declaring to support and or use. In Evas, interfaces are
* very simple: no interface inheritance, no interface
* overriding. Their purpose is to extend an object's capabilities and
* behavior beyond the sub-classing schema.
*
* Here, together with a custom smart object, we create and declare
* the object as using an Evas interface. It'll have a custom
* function, too, besides the @c add() and del() obligatory ones. To
* demonstrate interface data, which is bound to object @b instances,
* we'll have a string as this data.
*
* Here is where we declare our interface:
* @skip static const char iface1_data[]
* @until (Evas_Smart_Interface *)&iface1, NULL
* @until };
*
* Note that there's error checking for interfaces creation, by means of
* the @c add() method's return value (@c _iface1_add(), here).
*
* Now note that here we are filling in the interface's fields dynamically.
* Let's move on to that code region:
*
* @dontinclude evas-smart-interface.c
* @skip iface = (Evas_Smart_Example_Interface *)&iface1;
* @until d.smt = evas_smart_example_add(d.evas);
*
* As important as setting the function pointers, is declaring the @c
* private_size as to match exactly the size of the data blob we want
* to have allocated for us by Evas. This will happen automatically
* inside @c evas_smart_example_add(). Later, on this code, we deal
* exactly with that data blob, more specifically writing on it (as
* it's not done inside @c _iface1_add(), here:
*
* @dontinclude evas-smart-interface.c
* @skip iface = (Evas_Smart_Example_Interface *)evas_object_smart_interface_get
* @until }
*
* Before accessing the interface data, we exercise the interface
* fetching call evas_object_smart_interface_get(), with the name
* string we used to be interface's name. With that handle in hands,
* we issue evas_object_smart_interface_data_get() and write the
* string we want as data on that memory region. That will make up for
* the string you get on @c _iface1_del().
*
* The full example follows.
*
* @include evas-smart-interface.c
* @example evas-smart-interface.c
*/
/**
* @page Example_Evas_Text Evas text object example
*
* In this example, we illustrate how to use text objects in various
* manners.
*
* We place, in the canvas, a text object along with a border image to
* delimit its geometry. After we instantiate the text object, we set
* lots of properties on it to the initial ones from a preset list,
* which has the following declaration:
* @dontinclude evas-text.c
* @skip init values
* @until };
*
* Then, we set the text string itself, on it, with
* evas_object_text_text_set(). We set an explicit size of 30 points
* for our font, as you could see, what we check back with the
* getter evas_object_text_font_get().
*
* Look at how it translates to code:
* @dontinclude evas-text.c
* @skip evas_object_text_add
* @until fprintf
*
* Like in other Evas examples, one interacts with it by means of key
* commands:
* @dontinclude evas-text.c
* @skip static const char *commands
* @until ;
*
* Use the 't' key to exercise the evas_object_text_style_set()
* function on the text -- it will cycle through all styles on
* #Evas_Text_Style_Type (note we start on #EVAS_TEXT_STYLE_PLAIN,
* thus with no effects on it) and, with other keys, you'll be able to
* set properties applicable to individual styles on the text object.
*
* The 'z' key will change the text's @b size, keeping the font family
* for it. Use 'f' to change the font, keeping the last size
* set. There are three font families the example will cycle through:
*
* The 'b' command shows us that evas_object_color_set(), on a given
* text object, will change the text's @b base color. Experiment with
* it, which will cycle through the colors in the <c>.text</c> list in
* @c init_data.
*
* The 's', 'o', 'w' and 'g' keys will make the text object to cycle
* to the preset values on colors for shadow, outline, glow and 'glow
* 2' effects, respectively. Naturally, they will only take effect on
* the text styles which resemble them.
*
* The full example follows.
*
* @include evas-text.c
* @example evas-text.c
*/
/**
* @page tutorial_table Table Smart Object example
*
* This example will arrange rectangles of different sizes(and colors) in a
* table. While it's possible to create the same layout we are doing here by
* positioning each rectangle independently, using a table makes it a lot
* easier, since the table will control layout of all the objects, allowing you
* to move, resize or hide the entire table.
*
* We'll start with creating the table, setting it to
* EVAS_OBJECT_TABLE_HOMOGENEOUS_NONE to have maximum flexibility and setting
* its padding to 0:
* @dontinclude evas-table.c
* @skip object_table
* @until show
*
* We then create each rectangle and add it to the table:
* @until table_pack
* @until table_pack
* @until table_pack
* @until table_pack
* @note Each rectangle has a different minimum size based on how many rows and
* columns it will occupy.
*
* The full source for this example follow:
* @include evas-table.c
* @example evas-table.c
*/