3 ## extends ScrollMode to have a line-based cursor.
4 class LineCursorMode < ScrollMode
6 ## overwrite scrollmode binding on arrow keys for cursor movement
7 ## but j and k still scroll!
8 k.add :cursor_down, "Move cursor down one line", :down, 'j'
9 k.add :cursor_up, "Move cursor up one line", :up, 'k'
10 k.add :select, "Select this item", :enter
15 def initialize opts={}
16 @cursor_top = @curpos = opts.delete(:skip_top_rows) || 0
17 @load_more_callbacks = []
18 @load_more_callbacks_m = Mutex.new
19 @load_more_callbacks_active = false
30 ## callbacks when the cursor is asked to go beyond the bottom
32 @load_more_callbacks << b
35 def draw_line ln, opts={}
37 super ln, :highlight => true, :debug => opts[:debug]
43 def ensure_mode_validity
45 raise @curpos.inspect unless @curpos.is_a?(Integer)
46 c = @curpos.clamp topline, botline - 1
47 c = @cursor_top if c < @cursor_top
48 buffer.mark_dirty unless c == @curpos
53 return if @curpos == p
54 @curpos = p.clamp @cursor_top, lines
58 ## override search behavior to be cursor-based
59 def search_goto_line line
69 def search_start_line; @curpos end
71 def line_down # overwrite scrollmode
73 call_load_more_callbacks([topline + buffer.content_height - lines, 10].max) if topline + buffer.content_height > lines
74 set_cursor_pos topline if @curpos < topline
77 def line_up # overwrite scrollmode
79 set_cursor_pos botline - 1 if @curpos > botline - 1
83 call_load_more_callbacks buffer.content_height if @curpos == lines - 1
84 return false unless @curpos < lines - 1
86 if @curpos >= botline - 1
88 set_cursor_pos topline
102 return false unless @curpos > @cursor_top
103 if @curpos == topline
104 old_topline = topline
106 set_cursor_pos [old_topline - 1, topline].max
110 draw_line @curpos + 1
119 def page_up # overwrite
120 if topline <= @cursor_top
121 set_cursor_pos @cursor_top
123 relpos = @curpos - topline
125 set_cursor_pos topline + relpos
129 ## more complicated than one might think. three behaviors.
131 ## if we're on the last page, and it's not a full page, just move
132 ## the cursor down to the bottom and assume we can't load anything
133 ## else via the callbacks.
134 if topline > lines - buffer.content_height
135 set_cursor_pos(lines - 1)
137 ## if we're on the last page, and it's a full page, try and load
138 ## more lines via the callbacks and then shift the page down
139 elsif topline == lines - buffer.content_height
140 call_load_more_callbacks buffer.content_height
143 ## otherwise, just move down
145 relpos = @curpos - topline
147 set_cursor_pos [topline + relpos, lines - 1].min
153 set_cursor_pos @cursor_top
157 super if topline < (lines - buffer.content_height)
158 set_cursor_pos(lines - 1)
165 @status = l > 0 ? "line #{@curpos + 1} of #{l}" : ""
168 def call_load_more_callbacks size
170 @load_more_callbacks_m.synchronize do
171 if @load_more_callbacks_active
174 @load_more_callbacks_active = true
180 @load_more_callbacks.each { |c| c.call size }
181 @load_more_callbacks_active = false