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 def line_down # overwrite scrollmode
60 call_load_more_callbacks([topline + buffer.content_height - lines, 10].max) if topline + buffer.content_height > lines
61 set_cursor_pos topline if @curpos < topline
64 def line_up # overwrite scrollmode
66 set_cursor_pos botline - 1 if @curpos > botline - 1
70 call_load_more_callbacks buffer.content_height if @curpos == lines - 1
71 return false unless @curpos < lines - 1
73 if @curpos >= botline - 1
75 set_cursor_pos topline
89 return false unless @curpos > @cursor_top
93 set_cursor_pos [old_topline - 1, topline].max
106 def page_up # overwrite
107 if topline <= @cursor_top
108 set_cursor_pos @cursor_top
110 relpos = @curpos - topline
112 set_cursor_pos topline + relpos
116 ## more complicated than one might think. three behaviors.
118 ## if we're on the last page, and it's not a full page, just move
119 ## the cursor down to the bottom and assume we can't load anything
120 ## else via the callbacks.
121 if topline > lines - buffer.content_height
122 set_cursor_pos(lines - 1)
124 ## if we're on the last page, and it's a full page, try and load
125 ## more lines via the callbacks and then shift the page down
126 elsif topline == lines - buffer.content_height
127 call_load_more_callbacks buffer.content_height
130 ## otherwise, just move down
132 relpos = @curpos - topline
134 set_cursor_pos [topline + relpos, lines - 1].min
140 set_cursor_pos @cursor_top
144 super if topline < (lines - buffer.content_height)
145 set_cursor_pos(lines - 1)
152 @status = l > 0 ? "line #{@curpos + 1} of #{l}" : ""
155 def call_load_more_callbacks size
157 @load_more_callbacks_m.synchronize do
158 if @load_more_callbacks_active
161 @load_more_callbacks_active = true
167 @load_more_callbacks.each { |c| c.call size }
168 @load_more_callbacks_active = false