Add csv_viewer example

Author: kojix2

examples/gallery/csv_viewer.cr

@@ -0,0 +1,215 @@
+require "../../src/uing"
+require "csv"
+
+class CSVViewer
+  # Constants
+  WINDOW_WIDTH         = 600
+  WINDOW_HEIGHT        = 400
+  SUPPORTED_EXTENSIONS = %w[.csv .tsv]
+
+  # Instance variables
+  @csv_data = [] of Array(String)
+  @column_count = 0
+  @table : UIng::Table
+  @table_model : UIng::Table::Model
+  @hbox : UIng::Box
+  @window : UIng::Window
+
+  def initialize
+    UIng.init
+
+    # Initialize UI components directly
+    @hbox = UIng::Box.new :horizontal
+
+    # Create initial table model and table directly in initialize
+    model_handler = UIng::Table::Model::Handler.new do
+      num_columns { @column_count > 0 ? @column_count : 1 }
+      column_type { |column| UIng::Table::Value::Type::String }
+      num_rows { @csv_data.size }
+      cell_value do |row, column|
+        if row < @csv_data.size && column < @csv_data[row].size
+          UIng::Table::Value.new(@csv_data[row][column])
+        else
+          UIng::Table::Value.new("")
+        end
+      end
+      set_cell_value { |row, column, value| }
+    end
+
+    @table_model = UIng::Table::Model.new(model_handler)
+
+    @table = UIng::Table.new(@table_model) do
+      if @column_count > 0
+        (0...@column_count).each do |i|
+          append_text_column(generate_column_name(i), i, -1)
+        end
+      else
+        # Default single column if no data loaded yet
+        append_text_column("A", 0, -1)
+      end
+    end
+
+    @hbox.append(@table, true)
+
+    # Create menu after UI components are initialized
+    setup_menu
+
+    @window = UIng::Window.new("CSV Viewer", WINDOW_WIDTH, WINDOW_HEIGHT, menubar: true)
+    @window.child = @hbox
+  end
+
+  private def generate_column_name(index : Int32) : String
+    result = ""
+    temp = index
+    while temp >= 0
+      result = ('A'.ord + (temp % 26)).chr.to_s + result
+      temp = temp // 26 - 1
+    end
+    result
+  end
+
+  private def load_csv_data(filename : String) : Int32
+    separator = File.extname(filename).downcase == ".tsv" ? '\t' : ','
+
+    File.open(filename) do |file|
+      new_data = CSV.parse(file, separator: separator)
+      return 0 if new_data.empty?
+
+      @csv_data.clear
+      @csv_data.concat(new_data)
+      columns = @csv_data.first?.try(&.size) || 0
+      puts "Loaded file: #{filename} (#{@csv_data.size} rows, #{columns} columns)"
+      columns
+    end
+  rescue ex : Exception
+    puts "Error loading file: #{ex.message}"
+    0
+  end
+
+  private def create_table_with_columns(column_count : Int32)
+    model_handler = UIng::Table::Model::Handler.new do
+      num_columns { column_count }
+      column_type { |column| UIng::Table::Value::Type::String }
+      num_rows { @csv_data.size }
+      cell_value do |row, column|
+        if row < @csv_data.size && column < @csv_data[row].size
+          UIng::Table::Value.new(@csv_data[row][column])
+        else
+          UIng::Table::Value.new("")
+        end
+      end
+      set_cell_value { |row, column, value| }
+    end
+
+    @table_model = UIng::Table::Model.new(model_handler)
+
+    @table = UIng::Table.new(@table_model) do
+      (0...column_count).each do |i|
+        append_text_column(generate_column_name(i), i, -1)
+      end
+    end
+
+    @hbox.append(@table, true)
+  end
+
+  private def clear_table_data
+    old_count = @csv_data.size
+    (old_count - 1).downto(0) do |i|
+      @table_model.row_deleted(i)
+    end
+  end
+
+  private def destroy_current_table
+    @hbox.delete(0)
+    @table.destroy
+    @table_model.free
+  end
+
+  private def recreate_table(new_column_count : Int32)
+    puts "Column count changed from #{@column_count} to #{new_column_count}, recreating table"
+
+    destroy_current_table
+    create_table_with_columns(new_column_count)
+
+    puts "Table updated with new data"
+  end
+
+  private def update_existing_table
+    @csv_data.each_with_index do |_, i|
+      @table_model.row_inserted(i)
+    end
+
+    puts "Table updated with new data"
+  end
+
+  private def update_table_with_file(filename : String) : Bool
+    puts "Opening file: #{filename}"
+
+    # Clear existing data
+    clear_table_data
+
+    new_column_count = load_csv_data(filename)
+    return false if new_column_count == 0
+
+    if new_column_count != @column_count && new_column_count > 0
+      recreate_table(new_column_count)
+    else
+      update_existing_table
+    end
+
+    @column_count = new_column_count
+    true
+  end
+
+  private def setup_menu
+    UIng::Menu.new("File") do
+      append_item("Open").on_clicked do |w|
+        if filename = w.open_file
+          update_table_with_file(filename)
+        end
+      end
+      append_separator
+      append_quit_item
+    end
+  end
+
+  private def setup_initial_data
+    return unless ARGV.size > 0
+
+    filename = ARGV[0]
+    return unless File.exists?(filename)
+
+    extension = File.extname(filename).downcase
+    if SUPPORTED_EXTENSIONS.includes?(extension)
+      update_table_with_file(filename)
+    else
+      puts "Error: File must have #{SUPPORTED_EXTENSIONS.join(" or ")} extension"
+    end
+  end
+
+  # Clean up resources
+  private def cleanup
+    @hbox.delete(0)
+    @table.destroy
+    @table_model.free
+    UIng.quit
+  end
+
+  # Main application loop
+  def run
+    setup_initial_data
+
+    @window.on_closing do
+      cleanup
+      true
+    end
+
+    @window.show
+    UIng.main
+  ensure
+    UIng.uninit
+  end
+end
+
+viewer = CSVViewer.new
+viewer.run