checkbox: Adding third state (Indeterminate) support in checkbox

Summary:
Checkbox should support a third state "indeterminate" along with "Checked" and "Unchecked"
This third state is a state of checkbox which is shown when checkbox is neither Checked nor Unchecked.

- Added this new feature on the basis of a boolean variable's value.
- By default this boolean variable is disabled and checkbox will treat like old way.
- While adding this, I kept in mind, that applications which are already using checkbox, should not be affected, so I used 0=False=Unchecked, 1=True=Checked, and 2=Indeterminate
- Also added an example check_example_o2.c, which is using checkbox with both ways, using boolean, and using enum.
- Now also values can be set using boolean values, but it will give a type casting warning. As a boolean doen't support third state, so I used an enum int like.

- Added APIs to enable disable third state mode. elm_check_three_state_mode_set(check_obj, bool_val), and elm_check_three_state_mode_get(check_obj)
- Modified old APIs which were setting or getting states of checkbox.
- Added a state in theme of checkbox, with third state image.

Reviewers: seoz, raster, Sergeant_Whitespace, Hermet

Subscribers: Hermet, Sergeant_Whitespace, sachin.dev

Differential Revision: https://phab.enlightenment.org/D2249

1 files changed, 111 insertions, 0 deletions

diff --git a/src/examples/check_example_02.c b/src/examples/check_example_02.c
new file mode 100644
index 000000000..6aa0a1cfd
--- /dev/null
+++ b/src/examples/check_example_02.c
@@ -0,0 +1,111 @@
+//Compile with:
+//gcc -o check_example_02  check_example_02.c -g `pkg-config --cflags --libs elementary` && ./check_example_02
+
+#include <Elementary.h>
+
+Evas_Object *cb, *cb1, *cb2, *cb3;
+
+static void
+_print(void *data, Evas_Object *obj, void *event_info)
+{
+   if (!elm_check_three_state_mode_get(cb))
+     {
+        printf("check0 %smarked\n", *((Eina_Bool*)data) ? "" : "un");
+     }
+   else
+     {
+        printf("check0 elm_check_state_get() value is %d (%s)\n", elm_check_state_get(cb), *((Eina_Bool*)data) ? "EINA_TRUE" : "EINA_FALSE");
+     }
+}
+
+static void
+_print1(void *data, Evas_Object *obj, void *event_info)
+{
+   Check_State st = elm_check_state_get(cb1);
+   if (st == _CHECK_STATE_CHECKED)
+     printf("check1 elm_check_state_get() value is %d (%s)\n", st, "_CHECK_STATE_CHECKED");
+   else if (st == _CHECK_STATE_INDETERMINATE)
+     printf("check1 elm_check_state_get() value is %d (%s)\n", st, "_CHECK_STATE_INDETERMINATE");
+   else
+     printf("check1 elm_check_state_get() value is %d (%s)\n", st, "_CHECK_STATE_UNCHECKED");
+}
+
+static void
+_print2(void *data, Evas_Object *obj, void *event_info)
+{
+   printf("Currently three state mode is: %s\n", elm_check_three_state_mode_get(cb) ? "On" : "Off");
+   elm_check_three_state_mode_set(cb, elm_check_state_get(cb2));
+   elm_check_three_state_mode_set(cb1, elm_check_state_get(cb2));
+   printf("Three state mode is changed to: %s\n", elm_check_three_state_mode_get(cb) ? "On" : "Off");
+}
+
+static void
+_print3(void *data, Evas_Object *obj, void *event_info)
+{
+   elm_object_disabled_set(cb, elm_check_state_get(cb3));
+   elm_object_disabled_set(cb1, elm_check_state_get(cb3));
+   printf("Checkbox disable mode is : %s\n", elm_check_state_get(cb3) ? "Enabled" : "Disabled");
+}
+
+EAPI_MAIN int
+elm_main(int argc, char **argv)
+{
+   Evas_Object *win, *icon;
+   Eina_Bool value, *value2, *value3;
+   Check_State *value1;
+
+   elm_policy_set(ELM_POLICY_QUIT, ELM_POLICY_QUIT_LAST_WINDOW_CLOSED);
+
+   win = elm_win_util_standard_add("check", "Check");
+   elm_win_autodel_set(win, EINA_TRUE);
+
+   cb = elm_check_add(win);
+   elm_object_text_set(cb, "check0 using bool");
+   elm_check_state_pointer_set(cb, &value);
+   elm_check_state_set(cb, EINA_FALSE);
+   evas_object_smart_callback_add(cb, "changed", _print, &value);
+   evas_object_move(cb, 10, 10);
+   evas_object_resize(cb, 250, 30);
+   evas_object_show(cb);
+
+   cb1 = elm_check_add(win);
+   elm_object_text_set(cb1, "check1 using enum");
+   elm_check_state_pointer_set(cb1, (Check_State *)&value1);
+   elm_check_state_set(cb1, (Check_State)_CHECK_STATE_CHECKED);
+   evas_object_smart_callback_add(cb1, "changed", _print1, &value1);
+   evas_object_move(cb1, 10, 50);
+   evas_object_resize(cb1, 250, 30);
+   evas_object_show(cb1);
+
+   icon = evas_object_rectangle_add(evas_object_evas_get(win));
+   evas_object_color_set(icon, 0, 255, 0, 255);
+   evas_object_resize(icon, 20, 20);
+   evas_object_show(icon);
+
+   cb2 = elm_check_add(win);
+   elm_object_text_set(cb2, "Enable three state mode in above checkboxes");
+   elm_check_state_pointer_set(cb2, (Check_State *)&value2);
+   elm_check_state_set(cb2, (Check_State)_CHECK_STATE_UNCHECKED);
+   evas_object_smart_callback_add(cb2, "changed", _print2, &value2);
+   elm_object_part_content_set(cb2, "icon", icon);
+   evas_object_move(cb2, 10, 90);
+   evas_object_resize(cb2, 250, 30);
+   evas_object_show(cb2);
+
+   cb3 = elm_check_add(win);
+   elm_object_text_set(cb3, "Enable/Disable checkboxes");
+   elm_check_state_pointer_set(cb3, (Check_State *)&value3);
+   elm_check_state_set(cb3, (Check_State)_CHECK_STATE_UNCHECKED);
+   evas_object_smart_callback_add(cb3, "changed", _print3, &value3);
+   evas_object_move(cb3, 10, 130);
+   evas_object_resize(cb3, 250, 30);
+   evas_object_show(cb3);
+
+   evas_object_resize(win, 200, 190);
+   evas_object_show(win);
+
+   elm_run();
+
+   return 0;
+}
+ELM_MAIN()