efl/legacy/elementary/doc/examples.dox

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/**
* @page Examples Examples
*
* Here is a page with Elementary examples.
*
* @ref bg_01_example_page
*
* @ref bg_02_example_page
*
* @ref bg_03_example_page
*
* @ref actionslider_example_page
*
* @ref elm_animator_example_page_01
*
* @ref transit_example_01_explained
*
* @ref transit_example_02_explained
*
* @ref general_functions_example_page
*/
/**
* @page bg_01_example_page elm_bg - Plain color background.
* @dontinclude bg_example_01.c
*
* The full code for this example can be found at @ref bg_example_01_c,
* in the function @c test_bg_plain. It's part of the @c elementar_test
* suite, and thus has the code for the three examples referenced by this
* documentation.
*
* This first example just sets a default background with a plain color. The
* first part consists of creating an Elementary window. It's the common
* piece of code that you'll see everywhere in Elementary: @skip elm_main
* @until autodel_set
*
* Now we really create our background object, using the window object as
* its parent:
*
* @skipline bg_add
*
* Then we set the size hints of the background object so that it will use
* all space available for it, and then add it as a resize object to the
* window, making it visible in the end:
*
* @skip size_hint_weight_set
* @until resize_object_add
*
* See @ref evas_object_size_hint_weight_set and elm_win_resize_object_add()
* for more detailed info about these functions.
*
* The end of the example is quite simple, just setting the minimum and
* maximum size of the background, so the Elementary window knows that it
* has to have at least the minimum size. The background also won't scale to
* a size above its maximum. Then we resize the window and show it in the
* end:
*
* @skip set size hints
* @until }
*
* And here we finish our very simple background object usage example.
*/
/**
* @page bg_02_example_page elm_bg - Image background.
* @dontinclude bg_example_02.c
*
* The full code for this example can be found at @ref bg_example_02_c,
* in the function @c test_bg_image. It's part of the @c elementar_test
* suite, and thus has the code for the three examples referenced by this
* documentation.
*
* This is the second example, and shows how to use the Elementary
* background object to set an image as background of your application.
*
* We start this example exactly in the same way as the previous one, even
* when creating the background object:
*
* @skip elm_main
* @until bg_add
*
* Now it's the different part.
*
* Our background will have an image, that will be displayed over the
* background color. Before loading the image, we set the load size of the
* image. The load size is a hint about the size that we want the image
* displayed in the screen. It's not the exact size that the image will have,
* but usually a bit bigger. The background object can still be scaled to a
* size bigger than the one set here. Setting the image load size to
* something smaller than its real size will reduce the memory used to keep
* the pixmap representation of the image, and the time to load it. Here we
* set the load size to 20x20 pixels, but the image is loaded with a size
* bigger than that (since it's just a hint):
*
* @skipline load_size_set
*
* And set our background image to be centered, instead of stretched or
* scaled, so the effect of the elm_bg_load_size_set() can be easily
* understood:
*
* @skipline option_set
*
* We need a filename to set, so we get one from the previous installed
* images in the @c PACKAGE_DATA_DIR, and write its full path to a buffer.
* Then we use this buffer to set the filename in the background object:
*
* @skip snprintf
* @until bg_file_set
*
* Notice that the third argument of the elm_bg_file_set() function is @c
* NULL, since we are setting an image to this background. This function
* also supports setting an edje group as background, in which case the @c
* group parameter wouldn't be @c NULL, but be the name of the group
* instead.
*
* Finally, we can set the size hints, add the background as a resize
* object, and resize the window, exactly the same thing we do in the @ref
* bg_01_example_page example:
*
* @skip size_hint
* @until }
*
* And this is the end of this example.
*
* This example will look like this:
* @image html screenshots/bg_01.png
* @image latex screenshots/bg_01.eps
*/
/**
* @page bg_03_example_page elm_bg - Background properties.
* @dontinclude bg_example_03.c
*
* The full code for this example can be found at @ref bg_example_03_c, in the
* function @c test_bg_options, with the callbacks @c _cb_overlay_changed, @c
* _cb_color_changed and @c _cb_radio_changed defined in the beginning of the
* file. It's part of the @c elementar_test suite, and thus has the code for
* the three examples referenced by this documentation.
*
* This example will show the properties available for the background object,
* and will use of some more widgets to set them.
*
* In order to do this, we will set some callbacks for these widgets. The
* first is for the radio buttons that will be used to choose the option
* passed as argument to elm_bg_option_set():
*
* @skip _cb_radio_changed
* @until }
*
* The next callback will be used when setting the overlay (using
* elm_bg_overlay_set()):
*
* @skip _cb_overlay_changed
* @until }
* @until }
*
* And the last one, used to set the color (with elm_bg_color_set()):
*
* @skip _cb_color_changed
* @until }
*
* We will get back to what these functions do soon. If you want to know more
* about how to set these callbacks and what these widgets are, look for:
* @li elm_radio_add()
* @li elm_check_add()
* @li elm_spinner_add()
*
* Now going to the main function, @c test_bg_options, we have the common
* code with the other examples:
*
* @skip bg-options
* @until autodel_set
*
* We add a plain background to this window, so it will have the default
* background color behind everything:
*
* @skip bg = elm_bg_add
* @until evas_object_show(bg)
*
* Then we add a vertical box (elm_box_add()) that will hold the background
* object that we are going to play with, as well as a horizontal box that
* will hold widgets:
*
* @skip elm_box_add
* @until evas_object_show
*
* Now we add the background object that is going to be of use for our
* example. It is an image background, as used in @ref bg_02_example_page ,
* so the code should be familiar:
*
* @skip elm_bg_add
* @until evas_object_show
*
* Notice the call to elm_box_pack_end(): it will pack the background object
* in the end of the Elementary box declared above. Just refer to that
* documentation for more info.
*
* Since this Elementary background is already an image background, we are
* going to play with its other properties. We will change its option
* (CENTER, SCALE, STRETCH, TILE), its color (RGB), and add an overlay to it.
* For all of these properties, we are going to add widgets that will
* configure them.
*
* First, lets add the horizontal box that will hold these widgets:
* @skip hbox
* @until align_set
*
* For now, just consider this @c hbox as a rectangle that will contain the
* widgets, and will distribute them horizontally inside its content. Then we
* add radio buttons that will allow us to choose the property to use with
* this background:
*
* @skip radio_add
* @until evas_object_show
*
* Again, I won't give details about the use of these widgets, just look for
* their documentation if necessary. It's enough to know for now that we are
* packing them in the @c hbox, setting a label for them, and the most
* important parts: setting its value to @c ELM_BG_OPTION_CENTER and its
* callback to @c _cb_radio_changed (the function defined in the beginning of
* this example). We do this for the next 3 radio buttons added after this
* one, each of them with a different value.
*
* Now taking a look at the code of the callback @c _cb_radio_changed again,
* it will call elm_bg_option_set() with the value set from the checked radio
* button, thus setting the option for this background. The background is
* passed as argument to the @p data parameter of this callback, and is
* referenced here as @c o_bg.
*
* Later we set the default value for this radio button:
*
* @skipline elm_radio_value_set
*
* Then we add a checkbox for the elm_bg_overlay_set() function:
*
* @skip check_add
* @until evas_object_show
*
* Now look at the code of the @c _cb_overlay_changed again. If the checkbox
* state is checked, an overlay will be added to the background. It's done by
* creating an Edje object, and setting it with elm_bg_overlay_set() to the
* background object. For information about what are and how to set Edje
* object, look at the Edje documentation.
*
* Finally we add a spinner object (elm_spinner_add()) to be used to select
* the color of our background. In its callback it's possible to see the call
* to elm_bg_color_set(), which will change the color of this background.
* This color is used by the background to fill areas where the image doesn't
* cover (in this case, where we have an image background). The spinner is
* also packed into the @c hbox :
*
* @skip elm_spinner_add
* @until evas_object_show
*
* Then we just have to pack the @c hbox inside the @c box, set some size
* hints, and show our window:
*
* @skip pack_end
* @until }
*
* Now to see this code in action, open elementary_test, and go to the "Bg
* Options" test. It should demonstrate what was implemented here.
*/
/**
* @page actionslider_example_page Actionslider usage
* @dontinclude actionslider_example_01.c
*
* For this example we are going to assume knowledge of evas smart callbacks
* and some basic evas object functions. Elementary is not meant to be used
* without evas, if you're not yet familiar with evas it probably is worth
* checking that out.
*
* And now to the example, when using Elementary we start by including
* Elementary.h:
* @skipline #include
*
* Next we define some callbacks, they all share the same signature because
* they are all to be used with evas_object_smart_callback_add().
* The first one just prints the selected label(in two different ways):
* @until }
*
* This next callback is a little more interesting, it makes the selected
* label magnetic(except if it's the center label):
* @until }
*
* This callback enables or disables the magnetic propertty of the center
* label:
* @until }
*
* And finally a callback to stop the main loop when the window is closed:
* @until }
*
* To be able to create our actionsliders we need to do some setup, but this
* isn't really relevant here, so if you want to know about that go @ref
* Win "here".
*
* With all that boring stuff out of the way we can proceed to creating some
* actionsliders.@n
* All actionsliders are created the same way:
* @skipline actionslider_add
* Next we must choose where the indicator starts, and for this one we choose
* the right, and set the right as magnetic:
* @skipline indicator_pos_set
* @until magnet_pos_set
*
* We then set the labels for the left and right, passing NULL as an argument
* to any of the labels makes that position have no label.
* @until Stop
*
* Furthermore we mark both left and right as enabled positions, if we didn't
* do this all three positions would be enabled:
* @until RIGHT
*
* Having the the enabled positions we now add a smart callback to change
* which position is magnetic, so that only the last selected position is
* magnetic:
* @until NULL
*
* And finally we set our printing callback and show the actionslider:
* @until object_show
* @skip pack_end
*
* For our next actionslider we are going to do much as we did for the
* previous except we are going to have the center as the magnet(and not
* change it):
* @skipline actionslider_add
* @skipline indicator_pos_set
* @until object_show
*
* And another actionslider, in this one the indicator starts on the left.
* It has labels only in the center and right, and both bositions are
* magnetic. Because the left doesn't have a label and is not magnetic once
* the indicator leaves it can't return:
* @skipline actionslider_add
* @skipline indicator_pos_set
* @until object_show
* @note The greyed out area is a @ref Styles "style".
*
* And now an actionslider with a label in the indicator, and whose magnet
* properties change based on what was last selected:
* @skipline actionslider_add
* @skipline indicator_pos_set
* @until object_show
* @note The greyed out area is a @ref Styles "style".
*
* We are almost done, this next one is just an actionslider with all
* positions magnetized and having every possible label:
* @skipline actionslider_add
* @skipline indicator_pos_set
* @until object_show
*
* And for our last actionslider we have one that turns the magnetic property
* on and off:
* @skipline actionslider_add
* @skipline indicator_pos_set
* @until object_show
*
* The example will look like this:
* @image html screenshots/actionslider_01.png
* @image latex screenshots/actionslider_01.eps
*
* See the full source code @ref actionslider_example_01 "here"
*/
/**
* @page elm_animator_example_page_01 Animator usage
* @dontinclude animator_example_01.c
*
* For this example we will be using a bit of evas, you could animate a
* elementary widget in much the same way, but to keep things simple we use
* an evas_object_rectangle.
*
* As every other example we start with our include and a simple callback to
* exit the app when the window is closed:
* @skipline #include
* @until }
*
* This next callback is the one that actually creates our animation, it
* changes the size, position and color of a rectangle given to it in @a
* data:
* @until }
*
* Next we have a callback that prints a string, nothing special:
* @until }
*
* This next callback is a little more interesting, it has a state variable
* to know if the animation is currently paused or running, and it toogles
* the state of the animation accordingly:
* @until }
* @until }
* @until }
*
* Finally we have a callback to stop the animation:
* @until }
*
* As with every example we need to do a bit of setup before we can actually
* use an animation, but for the purposes of this example that's not relevant
* so let's just skip to the good stuff, creating an animator:
* @skipline animator_add
* @note Since elm_animator is not a widget we can give it a NULL parent.
*
* Now that we have an elm_animator we set it's duration to 1 second:
* @line duration_set
*
* We would also like our animation to be reversible, so:
* @line reverse_set
*
* We also set our animation to repeat as many times as possible, which will
* mean that _end_cb will only be called after UINT_MAX * 2 seconds(UINT_MAX
* for the animation running forward and UNIT_MAX for the animation running
* backwards):
* @line repeat_set
*
* To add some fun to our animation we will use the IN_OUT curve style:
* @line curve_style
*
* To actually animate anything we need an operation callback:
* @line operation_callback
*
* Even though we set our animation to repeat for a very long time we are
* going to set a end callback to it:
* @line completion_callback
* @note Notice that stoping the animation with the stop button will not make
* _end_cb be called.
*
* Now that we have fully set up our animator we can tell it to start
* animating:
* @line animate
*
* There's a bit more of code that doesn't really matter to use so we skip
* right down to our last interesting point:
* @skipline animator_del
* @note Because we created our animator with no parent we need to delete it
* ourselves.
*
* The example should look like this:
* @image html screenshots/animator_example_01.png
* @image latex screenshots/animator_example_01.eps
* @n
* @image html screenshots/animator_example_02.png
* @image latex screenshots/animator_example_02.eps
* @n
* @image html screenshots/animator_example_03.png
* @image latex screenshots/animator_example_03.eps
*
* The full source code for this example can be found @ref
* animator_example_01_c "here"
*/
/**
* @page transit_example_03_c elm_transit - Combined effects and options.
*
* This example shows how to apply the following transition effects:
* @li translation
* @li color
* @li rotation
* @li wipe
* @li zoom
* @li resizing
*
* It allows you to apply more than one effect at once, and also allows to
* set properties like event_enabled, auto_reverse, repeat_times and
* tween_mode.
*
* @include transit_example_03.c
*/
/**
* @page transit_example_04_c elm_transit - Combined effects over two objects.
*
* This example shows how to apply the transition effects:
* @li flip
* @li resizable_flip
* @li fade
* @li blend
* over two objects. This kind of transition effect is used to make one
* object disappear and another one appear on its place.
*
* You can mix more than one effect of this type on the same objects, and the
* transition will apply both.
*
* @include transit_example_04.c
*/
/**
* @page transit_example_01_explained elm_transit - Basic transit usage.
* @dontinclude transit_example_01.c
*
* The full code for this example can be found at @ref transit_example_01_c.
*
* This example shows the simplest way of creating a transition and applying
* it to an object. Similarly to every other elementary example, we create a
* window, set its title, size, autodel property, and setup a callback to
* exit the program when finished:
*
* @skip on_done
* @until evas_object_resize
*
* We also add a resizeable white background to use behind our animation:
*
* @skip bg_add
* @until evas_object_show
*
* And then we add a button that we will use to demonstrate the effects of
* our animation:
*
* @skip button_add
* @until evas_object_show(win)
*
* Notice that we are not adding the button with elm_win_resize_object_add()
* because we don't want the window to control the size of the button. We
* will use the transition to change the button size, so it could conflict
* with something else trying to control that size.
*
* Now, the simplest code possible to create the resize animation:
*
* @skip transit_add
* @until transit_go
*
* As you can see, this code is very easy to understand. First, we create the
* transition itself with elm_transit_add(). Then we add the button to this
* transition with elm_transit_object_add(), which means that the transition
* will operate over this button. The effect that we want now is changing the
* object size from 100x50 to 300x150, and can be achieved by adding the
* resize effect with elm_transit_effect_resizing_add().
*
* Finally, we set the transition time to 5 seconds and start the transition
* with elm_transit_go(). If we wanted more effects applied to this
* button, we could add them to the same transition. See the
* @ref transit_example_03_c to watch many transitions being applied to an
* object.
*/
/**
* @page transit_example_02_explained elm_transit - Chained transitions.
* @dontinclude transit_example_02.c
*
* The full code for this example can be found at @ref transit_example_02_c.
*
* This example shows how to implement a chain of transitions. This chain is
* used to start a transition just after another transition ended. Similarly
* to every other elementary example, we create a window, set its title,
* size, autodel property, and setup a callback to exit the program when
* finished:
*
* @skip on_done
* @until evas_object_resize
*
* We also add a resizeable white background to use behind our animation:
*
* @skip bg_add
* @until evas_object_show
*
* This example will have a chain of 4 transitions, each of them applied to
* one button. Thus we create 4 different buttons:
*
* @skip button_add
* @until evas_object_show(bt4)
*
* Now we create a simple translation transition that will be started as soon
* as the program loads. It will be our first transition, and the other
* transitions will be started just after this transition ends:
*
* @skip transit_add
* @until transit_go
*
* The code displayed until now has nothing different from what you have
* already seen in @ref transit_example_01_explained, but now comes the new
* part: instead of creating a second transition that will start later using
* a timer, we create the it normally, and use
* elm_transit_chain_transit_add() instead of elm_transit_go. Since we are
* adding it in a chain after the first transition, it will start as soon as
* the first transition ends:
*
* @skip transit_add
* @until transit_chain_transit_add
*
* Finally we add the 2 other transitions to the chain, and run our program.
* It will make one transition start after the other finish, and there is the
* transition chain.
*/
/**
* @page general_functions_example_page General (top-level) functions example
* @dontinclude general_funcs_example.c
*
* As told in their documentation blocks, the
* elm_app_compile_*_dir_set() family of functions have to be called
* before elm_app_info_set():
* @skip tell elm about
* @until elm_app_info_set
*
* We are here setting the fallback paths to the compiling time target
* paths, naturally. If you're building the example out of the
* project's build system, we're assuming they are the canonical ones.
*
* After the program starts, elm_app_info_set() will actually run and
* then you'll see an intrincasy: Elementary does the prefix lookup @b
* twice. This is so because of the quicklaunch infrastructure in
* Elementary (@ref Start), which will register a predefined prefix
* for possible users of the launch schema. We're not hooking into a
* quick launch, so this first call can't be avoided.
*
* If you ran this example from your "bindir" installation
* directiory, no output will emerge from these both attempts -- it
* will find the "magic" file there registered and set the prefixes
* silently. Otherwise, you could get something like:
@verbatim
WARNING: Could not determine its installed prefix for 'ELM'
so am falling back on the compiled in default:
usr
implied by the following:
bindir = usr/lib
libdir = usr/lib
datadir = usr/share/elementary
localedir = usr/share/locale
Try setting the following environment variables:
ELM_PREFIX - points to the base prefix of install
or the next 4 variables
ELM_BIN_DIR - provide a specific binary directory
ELM_LIB_DIR - provide a specific library directory
ELM_DATA_DIR - provide a specific data directory
ELM_LOCALE_DIR - provide a specific locale directory
@endverbatim
* if you also didn't change those environment variables (remember
* they are also a valid way of communicating your prefix to the
* binary) - this is the scenario where it fallbacks to the paths set
* for compile time.
*
* Then, you can check the prefixes set on the standard output:
* @skip prefix was set to
* @until locale directory is
*
* In the fragment
* @skip by using this policy
* @until elm_win_autodel_set
* we demonstrate the use of Elementary policies. The policy defining
* under which circunstances our application should quit automatically
* is set to when its last window is closed (this one has just one
* window, though). This will save us from having to set a callback
* ourselves on the window, like done in @ref bg_example_01_c "this"
* example. Note that we need to tell the window to delete itself's
* object on a request to destroy the canvas coming, with
* elm_win_autodel_set().
*
* What follows is some boilerplate code, creating a frame with a @b
* button, our object of interest, and, below, widgets to change the
* button's behavior and exemplify the group of functions in question.
*
* @dontinclude general_funcs_example.c
* We enabled the focus highlight object for this window, so that you
* can keep track of the current focused object better:
* @skip elm_win_focus_highlight_enabled_set
* @until evas_object_show
* Use the tab key to navigate through the focus chain.
*
* @dontinclude general_funcs_example.c
* While creating the button, we exemplify how to use Elementary's
* finger size information to scale our UI:
* @skip fprintf(stdout, "Elementary
* @until evas_object_show
*
* @dontinclude general_funcs_example.c
* The first checkbox's callback is:
* @skip static void
* @until }
* When unsetting the checkbox, we disable the button, which will get a new
* decoration (greyed out) and stop receiving events. The focus chain
* will also ignore it.
*
* Following, there are 2 more buttons whose actions are focus/unfocus
* the top button, respectively:
* @skip focus callback
* @until }
* and
* @skip unfocus callback
* @until }
* Note the situations in which they won't take effect:
* - the button is not allowed to get focus or
* - the button is disabled
*
* The first restriction above you'll get by a second checkbox, whose
* callback is:
* @skip focus allow callback
* @until }
* Note that the button will still get mouse events, though.
*
* Next, there's a slider controlling the button's scale:
* @skip scaling callback
* @until }
*
* Experiment with it, so you understand the effect better. If you
* change its value, it will mess with the button's original size,
* naturally.
*
* The full code for this example can be found
* @ref general_functions_example_c "here".
*/
/**
* @page bg_example_01_c bg_example_01.c
* @include bg_example_01.c
* @example bg_example_01.c
*/
/**
* @page bg_example_02_c bg_example_02.c
* @include bg_example_02.c
* @example bg_example_02.c
*/
/**
* @page bg_example_03_c bg_example_03.c
* @include bg_example_03.c
* @example bg_example_03.c
*/
/**
* @page actionslider_example_01 Actionslider example
* @include actionslider_example_01.c
* @example actionslider_example_01.c
*/
/**
* @page animator_example_01_c Animator example 01
* @include animator_example_01.c
* @example animator_example_01.c
*/
/**
* @page transit_example_01_c Transit example 1
* @include transit_example_01.c
* @example transit_example_01.c
*/
/**
* @page transit_example_02_c Transit example 2
* @include transit_example_02.c
* @example transit_example_02.c
*/
/**
* @page general_functions_example_c General (top-level) functions example
* @include general_funcs_example.c
* @example general_funcs_example.c
*/