jbutton: add new bare-bones button widget for touch

CMakeLists.txt

@@ -34,6 +34,7 @@ add_library(${NAME} STATIC
   src/jframe.c
   src/jlist.c
   src/jscrolledlist.c
+  src/jbutton.c
   src/vec.c
   src/keymap.c
   ${ASSETS_${FXSDK_PLATFORM}}

include/justui/jbutton.h

@@ -0,0 +1,59 @@
+//---
+// JustUI.jbutton: Touchable multi-state click button
+//---
+
+#ifndef _J_JBUTTON
+#define _J_JBUTTON
+
+#include <justui/defs.h>
+#include <justui/jwidget.h>
+
+#include <gint/display.h>
+
+/* jbutton: Button with multiple states
+
+   This widget is your everyday interactible button. It responds to touch by
+   changing its background color for idle, focused and active states. It also
+   has a disabled states which can be used to make a "selected" visual.
+
+   TODO: Allow jbutton it to hold any widget inside.
+   TODO: jbutton's focus state is untested since I only tested touch.
+
+   Events:
+   * JBUTTON_TRIGGERED when activated. */
+
+enum {
+    JBUTTON_IDLE,
+    JBUTTON_ACTIVE,
+    JBUTTON_DISABLED,
+
+    JBUTTON_STATE_NUM,
+};
+
+typedef struct {
+    jwidget widget;
+
+    /* Text shown on the button; not owned by the button */
+    char const *text;
+    /* Rendering font */
+    font_t const *font;
+    /* Colors for all states */
+    color_t fg_colors[JBUTTON_STATE_NUM];
+    color_t bg_colors[JBUTTON_STATE_NUM];
+    /* Current state */
+    int state;
+
+} jbutton;
+
+/* Event IDs */
+extern uint16_t JBUTTON_TRIGGERED;
+
+/* jbutton_create(): Create a button */
+jbutton *jbutton_create(char const *text, void *parent);
+
+/* Trivial properties */
+void jbutton_set_text(jbutton *b, char const *text);
+void jbutton_set_font(jbutton *b, font_t const *font);
+void jbutton_set_disabled(jbutton *b, bool disabled);
+
+#endif /* _J_JBUTTON */

src/jbutton.c

@@ -0,0 +1,139 @@
+#include <justui/jwidget.h>
+#include <justui/jwidget-api.h>
+#include <justui/jbutton.h>
+#include <justui/config.h>
+
+#include <stdlib.h>
+
+J_DEFINE_WIDGET(jbutton, csize, render, event)
+J_DEFINE_EVENTS(JBUTTON_TRIGGERED)
+
+static void jbutton_set_state(jbutton *b, int state)
+{
+    if((uint)state >= JBUTTON_STATE_NUM || b->state == state)
+        return;
+    b->state = state;
+    jwidget_set_background(b, b->bg_colors[state]);
+    b->widget.update = 1;
+}
+
+jbutton *jbutton_create(char const *text, void *parent)
+{
+    if(jbutton_type_id < 0)
+        return NULL;
+
+    jbutton *b = malloc(sizeof *b);
+    if(!b)
+        return NULL;
+
+    jwidget_init(&b->widget, jbutton_type_id, parent);
+    jwidget_set_focus_policy(b, J_FOCUS_POLICY_ACCEPT);
+
+    b->text = text ? text : "";
+    b->font = dfont_default();
+
+#if GINT_RENDER_MONO
+    b->fg_colors[JBUTTON_IDLE] = C_WHITE;
+    b->fg_colors[JBUTTON_ACTIVE] = C_WHITE;
+    b->fg_colors[JBUTTON_DISABLED] = C_BLACK;
+    b->bg_colors[JBUTTON_IDLE] = C_BLACK;
+    b->bg_colors[JBUTTON_ACTIVE] = C_BLACK;
+    b->bg_colors[JBUTTON_DISABLED] = C_WHITE;
+    jwidget_set_padding(b, 1, 2, 1, 2);
+#endif
+#if GINT_RENDER_RGB
+    b->fg_colors[JBUTTON_IDLE] = C_WHITE;
+    b->fg_colors[JBUTTON_ACTIVE] = C_WHITE;
+    b->fg_colors[JBUTTON_DISABLED] = C_RGB(8, 8, 8);
+    b->bg_colors[JBUTTON_IDLE] = C_BLACK;
+    b->bg_colors[JBUTTON_ACTIVE] = C_RGB(8, 8, 8);
+    b->bg_colors[JBUTTON_DISABLED] = C_RGB(24, 24, 24);
+    jwidget_set_padding(b, 2, 4, 2, 4);
+#endif
+
+    jbutton_set_state(b, JBUTTON_IDLE);
+    return b;
+}
+
+void jbutton_set_text(jbutton *b, char const *text)
+{
+    b->text = text ? text : "";
+    b->widget.dirty = 1;
+}
+
+void jbutton_set_font(jbutton *b, font_t const *font)
+{
+    b->font = font ? font : dfont_default();
+    b->widget.dirty = 1;
+}
+
+void jbutton_set_disabled(jbutton *b, bool disabled)
+{
+    if(disabled)
+        jbutton_set_state(b, JBUTTON_DISABLED);
+    else if(b->state == JBUTTON_DISABLED)
+        jbutton_set_state(b, JBUTTON_IDLE);
+}
+
+//---
+// Polymorphic widget operations
+//---
+
+void jbutton_poly_csize(void *b0)
+{
+    jbutton *b = b0;
+    int w, h;
+    dsize(b->text, b->font ? b->font : dfont_default(), &w, &h);
+    b->widget.w = w;
+    b->widget.h = h;
+}
+
+void jbutton_poly_render(void *b0, int x, int y)
+{
+    jbutton *b = b0;
+    int cw = jwidget_content_width(b);
+    int ch = jwidget_content_height(b);
+
+    int fg = b->fg_colors[b->state];
+    font_t const *old_font = dfont(b->font);
+    dtext_opt(x + cw / 2, y + ch / 2, fg, C_NONE, DTEXT_CENTER, DTEXT_MIDDLE,
+        b->text, -1);
+    dfont(old_font);
+}
+
+bool jbutton_poly_event(void *b0, jevent e)
+{
+    jbutton *b = b0;
+    key_event_t ev = { .type = KEYEV_NONE };
+    if(e.type == JWIDGET_KEY)
+        ev = e.key;
+
+#if J_CONFIG_TOUCH
+    bool accepts_touch = b->state != JBUTTON_DISABLED;
+    if((ev.type == KEYEV_TOUCH_DOWN || ev.type == KEYEV_TOUCH_DRAG ||
+        ev.type == KEYEV_TOUCH_UP) && accepts_touch) {
+        int lx = ev.x - jwidget_absolute_padding_x(b);
+        int ly = ev.y - jwidget_absolute_padding_y(b);
+        uint cw = jwidget_padding_width(b);
+        uint ch = jwidget_padding_height(b);
+        bool inside = (uint)lx < cw && (uint)ly < ch;
+
+        if(ev.type == KEYEV_TOUCH_DOWN)
+            jbutton_set_state(b, JBUTTON_ACTIVE);
+        if(ev.type == KEYEV_TOUCH_DRAG)
+            jbutton_set_state(b, inside ? JBUTTON_ACTIVE : JBUTTON_IDLE);
+        if(ev.type == KEYEV_TOUCH_UP && b->state == JBUTTON_ACTIVE) {
+            jbutton_set_state(b, JBUTTON_IDLE);
+            jwidget_emit(b, (jevent){ .type = JBUTTON_TRIGGERED });
+        }
+        return true;
+    }
+#endif
+
+    if(ev.type == KEYEV_DOWN && (ev.key == KEY_EXE || ev.key == KEY_OK)) {
+        jwidget_emit(b, (jevent){ .type = JBUTTON_TRIGGERED });
+        return true;
+    }
+
+    return jwidget_poly_event(b, e);
+}