CSVデータクリーナー

クラス設計とコンストラクタ

App056クラスにアプリの全機能をまとめています。__init__でウィンドウ設定、_build_ui()でUI構築、process()でメイン処理を担当します。責任の分離により、コードが読みやすくなります。

import tkinter as tk
from tkinter import ttk, messagebox, filedialog
import csv
import os
import io
from collections import defaultdict


class App056:
    """CSVデータクリーナー"""

    def __init__(self, root):
        self.root = root
        self.root.title("CSVデータクリーナー")
        self.root.geometry("1000x620")
        self.root.configure(bg="#1e1e1e")
        self._original = []
        self._cleaned = []
        self._headers = []
        self._build_ui()

    def _build_ui(self):
        header = tk.Frame(self.root, bg="#252526", pady=6)
        header.pack(fill=tk.X)
        tk.Label(header, text="🧹 CSVデータクリーナー",
                 font=("Noto Sans JP", 12, "bold"),
                 bg="#252526", fg="#4fc3f7").pack(side=tk.LEFT, padx=12)

        # ツールバー
        tb = tk.Frame(self.root, bg="#2d2d2d", pady=4)
        tb.pack(fill=tk.X)
        ttk.Button(tb, text="📂 CSV読込",    command=self._load).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="▶ クリーン実行", command=self._clean).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="💾 保存",        command=self._save).pack(side=tk.LEFT, padx=4)

        # オプションパネル
        opt_f = tk.LabelFrame(self.root, text="クリーンオプション",
                               bg="#252526", fg="#ccc", font=("Arial", 9),
                               padx=8, pady=4)
        opt_f.pack(fill=tk.X, padx=8, pady=4)

        self.opt_empty_row  = tk.BooleanVar(value=True)
        self.opt_dup_row    = tk.BooleanVar(value=True)
        self.opt_trim       = tk.BooleanVar(value=True)
        self.opt_empty_col  = tk.BooleanVar(value=False)
        self.opt_lower_hdr  = tk.BooleanVar(value=False)
        self.opt_fill_empty = tk.BooleanVar(value=False)
        self.fill_val_var   = tk.StringVar(value="")

        opts = [
            ("空行を削除",         self.opt_empty_row),
            ("重複行を削除",       self.opt_dup_row),
            ("前後の空白を除去",   self.opt_trim),
            ("空列を削除",         self.opt_empty_col),
            ("ヘッダーを小文字に", self.opt_lower_hdr),
            ("空セルを埋める",     self.opt_fill_empty),
        ]
        for i, (label, var) in enumerate(opts):
            tk.Checkbutton(opt_f, text=label, variable=var,
                           bg="#252526", fg="#ccc", selectcolor="#3c3c3c",
                           activebackground="#252526",
                           font=("Arial", 9)).grid(
                row=i//3, column=i%3*2, sticky="w", padx=6)

        tk.Label(opt_f, text="埋める値:", bg="#252526", fg="#ccc",
                 font=("Arial", 9)).grid(row=1, column=4, sticky="w")
        ttk.Entry(opt_f, textvariable=self.fill_val_var,
                  width=10).grid(row=1, column=5, sticky="w")

        # 左右プレビュー
        paned = ttk.PanedWindow(self.root, orient=tk.HORIZONTAL)
        paned.pack(fill=tk.BOTH, expand=True, padx=8, pady=4)

        left = tk.Frame(paned, bg="#1e1e1e")
        paned.add(left, weight=1)
        tk.Label(left, text="元データ", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.orig_tree = self._make_tree(left)

        right = tk.Frame(paned, bg="#1e1e1e")
        paned.add(right, weight=1)
        tk.Label(right, text="クリーン後", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.clean_tree = self._make_tree(right)

        self.status_var = tk.StringVar(value="CSVファイルを読み込んでください")
        tk.Label(self.root, textvariable=self.status_var,
                 bg="#252526", fg="#858585", font=("Arial", 9),
                 anchor="w", padx=8).pack(fill=tk.X, side=tk.BOTTOM)

    def _make_tree(self, parent):
        frame = tk.Frame(parent, bg="#1e1e1e")
        frame.pack(fill=tk.BOTH, expand=True)
        tree = ttk.Treeview(frame, show="headings", selectmode="browse")
        sbx = ttk.Scrollbar(frame, orient=tk.HORIZONTAL, command=tree.xview)
        sby = ttk.Scrollbar(frame, command=tree.yview)
        tree.configure(xscrollcommand=sbx.set, yscrollcommand=sby.set)
        sby.pack(side=tk.RIGHT, fill=tk.Y)
        tree.pack(fill=tk.BOTH, expand=True)
        sbx.pack(fill=tk.X)
        return tree

    def _load(self):
        path = filedialog.askopenfilename(
            filetypes=[("CSV", "*.csv"), ("TSV", "*.tsv"), ("すべて", "*.*")])
        if not path:
            return
        try:
            enc = "utf-8-sig"
            with open(path, encoding=enc, errors="replace") as f:
                reader = csv.reader(f)
                rows = list(reader)
            if not rows:
                messagebox.showinfo("情報", "データが空です")
                return
            self._headers = rows[0]
            self._original = rows[1:]
            self._cleaned = list(self._original)
            self._show_tree(self.orig_tree, self._headers, self._original)
            self._show_tree(self.clean_tree, self._headers, self._cleaned)
            self.status_var.set(
                f"読込完了: {len(self._original)} 行 × {len(self._headers)} 列")
        except Exception as e:
            messagebox.showerror("エラー", str(e))

    def _show_tree(self, tree, headers, rows, max_rows=500):
        cols = [f"c{i}" for i in range(len(headers))]
        tree.configure(columns=cols)
        for i, h in enumerate(headers):
            tree.heading(f"c{i}", text=str(h))
            tree.column(f"c{i}", width=100, anchor="w")
        tree.delete(*tree.get_children())
        for row in rows[:max_rows]:
            tree.insert("", tk.END, values=row)

    def _clean(self):
        if not self._original and not self._headers:
            messagebox.showwarning("警告", "CSVを読み込んでください")
            return

        rows = [list(r) for r in self._original]
        headers = list(self._headers)

        # 前後空白除去
        if self.opt_trim.get():
            rows = [[c.strip() for c in r] for r in rows]
            headers = [h.strip() for h in headers]

        # ヘッダー小文字化
        if self.opt_lower_hdr.get():
            headers = [h.lower() for h in headers]

        # 空セルを埋める
        if self.opt_fill_empty.get():
            fill_val = self.fill_val_var.get()
            rows = [[c if c != "" else fill_val for c in r] for r in rows]

        # 空行削除
        if self.opt_empty_row.get():
            rows = [r for r in rows if any(c.strip() for c in r)]

        # 重複行削除
        if self.opt_dup_row.get():
            seen = set()
            unique = []
            for r in rows:
                key = tuple(r)
                if key not in seen:
                    seen.add(key)
                    unique.append(r)
            rows = unique

        # 空列削除
        if self.opt_empty_col.get() and rows:
            non_empty_cols = []
            for j in range(len(headers)):
                if any(j < len(r) and r[j].strip() for r in rows):
                    non_empty_cols.append(j)
            headers = [headers[j] for j in non_empty_cols]
            rows = [[r[j] if j < len(r) else "" for j in non_empty_cols]
                    for r in rows]

        self._cleaned = rows
        self._show_tree(self.clean_tree, headers, rows)
        removed = len(self._original) - len(rows)
        self.status_var.set(
            f"クリーン完了: {len(rows)} 行 (元 {len(self._original)} 行, "
            f"{removed} 行削除)")

    def _save(self):
        if not self._cleaned and not self._headers:
            messagebox.showwarning("警告", "データがありません")
            return
        path = filedialog.asksaveasfilename(
            defaultextension=".csv",
            filetypes=[("CSV", "*.csv")])
        if not path:
            return
        try:
            with open(path, "w", newline="", encoding="utf-8-sig") as f:
                writer = csv.writer(f)
                writer.writerow(self._headers)
                writer.writerows(self._cleaned)
            messagebox.showinfo("完了",
                                 f"{len(self._cleaned)} 行を保存しました:\n{path}")
            self.status_var.set(f"保存完了: {os.path.basename(path)}")
        except Exception as e:
            messagebox.showerror("エラー", str(e))


if __name__ == "__main__":
    root = tk.Tk()
    app = App056(root)
    root.mainloop()

UIレイアウトの構築

LabelFrameで入力エリアと結果エリアを視覚的に分けています。pack()で縦に並べ、expand=Trueで結果エリアが画面いっぱいに広がるよう設定しています。

import tkinter as tk
from tkinter import ttk, messagebox, filedialog
import csv
import os
import io
from collections import defaultdict


class App056:
    """CSVデータクリーナー"""

    def __init__(self, root):
        self.root = root
        self.root.title("CSVデータクリーナー")
        self.root.geometry("1000x620")
        self.root.configure(bg="#1e1e1e")
        self._original = []
        self._cleaned = []
        self._headers = []
        self._build_ui()

    def _build_ui(self):
        header = tk.Frame(self.root, bg="#252526", pady=6)
        header.pack(fill=tk.X)
        tk.Label(header, text="🧹 CSVデータクリーナー",
                 font=("Noto Sans JP", 12, "bold"),
                 bg="#252526", fg="#4fc3f7").pack(side=tk.LEFT, padx=12)

        # ツールバー
        tb = tk.Frame(self.root, bg="#2d2d2d", pady=4)
        tb.pack(fill=tk.X)
        ttk.Button(tb, text="📂 CSV読込",    command=self._load).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="▶ クリーン実行", command=self._clean).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="💾 保存",        command=self._save).pack(side=tk.LEFT, padx=4)

        # オプションパネル
        opt_f = tk.LabelFrame(self.root, text="クリーンオプション",
                               bg="#252526", fg="#ccc", font=("Arial", 9),
                               padx=8, pady=4)
        opt_f.pack(fill=tk.X, padx=8, pady=4)

        self.opt_empty_row  = tk.BooleanVar(value=True)
        self.opt_dup_row    = tk.BooleanVar(value=True)
        self.opt_trim       = tk.BooleanVar(value=True)
        self.opt_empty_col  = tk.BooleanVar(value=False)
        self.opt_lower_hdr  = tk.BooleanVar(value=False)
        self.opt_fill_empty = tk.BooleanVar(value=False)
        self.fill_val_var   = tk.StringVar(value="")

        opts = [
            ("空行を削除",         self.opt_empty_row),
            ("重複行を削除",       self.opt_dup_row),
            ("前後の空白を除去",   self.opt_trim),
            ("空列を削除",         self.opt_empty_col),
            ("ヘッダーを小文字に", self.opt_lower_hdr),
            ("空セルを埋める",     self.opt_fill_empty),
        ]
        for i, (label, var) in enumerate(opts):
            tk.Checkbutton(opt_f, text=label, variable=var,
                           bg="#252526", fg="#ccc", selectcolor="#3c3c3c",
                           activebackground="#252526",
                           font=("Arial", 9)).grid(
                row=i//3, column=i%3*2, sticky="w", padx=6)

        tk.Label(opt_f, text="埋める値:", bg="#252526", fg="#ccc",
                 font=("Arial", 9)).grid(row=1, column=4, sticky="w")
        ttk.Entry(opt_f, textvariable=self.fill_val_var,
                  width=10).grid(row=1, column=5, sticky="w")

        # 左右プレビュー
        paned = ttk.PanedWindow(self.root, orient=tk.HORIZONTAL)
        paned.pack(fill=tk.BOTH, expand=True, padx=8, pady=4)

        left = tk.Frame(paned, bg="#1e1e1e")
        paned.add(left, weight=1)
        tk.Label(left, text="元データ", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.orig_tree = self._make_tree(left)

        right = tk.Frame(paned, bg="#1e1e1e")
        paned.add(right, weight=1)
        tk.Label(right, text="クリーン後", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.clean_tree = self._make_tree(right)

        self.status_var = tk.StringVar(value="CSVファイルを読み込んでください")
        tk.Label(self.root, textvariable=self.status_var,
                 bg="#252526", fg="#858585", font=("Arial", 9),
                 anchor="w", padx=8).pack(fill=tk.X, side=tk.BOTTOM)

    def _make_tree(self, parent):
        frame = tk.Frame(parent, bg="#1e1e1e")
        frame.pack(fill=tk.BOTH, expand=True)
        tree = ttk.Treeview(frame, show="headings", selectmode="browse")
        sbx = ttk.Scrollbar(frame, orient=tk.HORIZONTAL, command=tree.xview)
        sby = ttk.Scrollbar(frame, command=tree.yview)
        tree.configure(xscrollcommand=sbx.set, yscrollcommand=sby.set)
        sby.pack(side=tk.RIGHT, fill=tk.Y)
        tree.pack(fill=tk.BOTH, expand=True)
        sbx.pack(fill=tk.X)
        return tree

    def _load(self):
        path = filedialog.askopenfilename(
            filetypes=[("CSV", "*.csv"), ("TSV", "*.tsv"), ("すべて", "*.*")])
        if not path:
            return
        try:
            enc = "utf-8-sig"
            with open(path, encoding=enc, errors="replace") as f:
                reader = csv.reader(f)
                rows = list(reader)
            if not rows:
                messagebox.showinfo("情報", "データが空です")
                return
            self._headers = rows[0]
            self._original = rows[1:]
            self._cleaned = list(self._original)
            self._show_tree(self.orig_tree, self._headers, self._original)
            self._show_tree(self.clean_tree, self._headers, self._cleaned)
            self.status_var.set(
                f"読込完了: {len(self._original)} 行 × {len(self._headers)} 列")
        except Exception as e:
            messagebox.showerror("エラー", str(e))

    def _show_tree(self, tree, headers, rows, max_rows=500):
        cols = [f"c{i}" for i in range(len(headers))]
        tree.configure(columns=cols)
        for i, h in enumerate(headers):
            tree.heading(f"c{i}", text=str(h))
            tree.column(f"c{i}", width=100, anchor="w")
        tree.delete(*tree.get_children())
        for row in rows[:max_rows]:
            tree.insert("", tk.END, values=row)

    def _clean(self):
        if not self._original and not self._headers:
            messagebox.showwarning("警告", "CSVを読み込んでください")
            return

        rows = [list(r) for r in self._original]
        headers = list(self._headers)

        # 前後空白除去
        if self.opt_trim.get():
            rows = [[c.strip() for c in r] for r in rows]
            headers = [h.strip() for h in headers]

        # ヘッダー小文字化
        if self.opt_lower_hdr.get():
            headers = [h.lower() for h in headers]

        # 空セルを埋める
        if self.opt_fill_empty.get():
            fill_val = self.fill_val_var.get()
            rows = [[c if c != "" else fill_val for c in r] for r in rows]

        # 空行削除
        if self.opt_empty_row.get():
            rows = [r for r in rows if any(c.strip() for c in r)]

        # 重複行削除
        if self.opt_dup_row.get():
            seen = set()
            unique = []
            for r in rows:
                key = tuple(r)
                if key not in seen:
                    seen.add(key)
                    unique.append(r)
            rows = unique

        # 空列削除
        if self.opt_empty_col.get() and rows:
            non_empty_cols = []
            for j in range(len(headers)):
                if any(j < len(r) and r[j].strip() for r in rows):
                    non_empty_cols.append(j)
            headers = [headers[j] for j in non_empty_cols]
            rows = [[r[j] if j < len(r) else "" for j in non_empty_cols]
                    for r in rows]

        self._cleaned = rows
        self._show_tree(self.clean_tree, headers, rows)
        removed = len(self._original) - len(rows)
        self.status_var.set(
            f"クリーン完了: {len(rows)} 行 (元 {len(self._original)} 行, "
            f"{removed} 行削除)")

    def _save(self):
        if not self._cleaned and not self._headers:
            messagebox.showwarning("警告", "データがありません")
            return
        path = filedialog.asksaveasfilename(
            defaultextension=".csv",
            filetypes=[("CSV", "*.csv")])
        if not path:
            return
        try:
            with open(path, "w", newline="", encoding="utf-8-sig") as f:
                writer = csv.writer(f)
                writer.writerow(self._headers)
                writer.writerows(self._cleaned)
            messagebox.showinfo("完了",
                                 f"{len(self._cleaned)} 行を保存しました:\n{path}")
            self.status_var.set(f"保存完了: {os.path.basename(path)}")
        except Exception as e:
            messagebox.showerror("エラー", str(e))


if __name__ == "__main__":
    root = tk.Tk()
    app = App056(root)
    root.mainloop()

イベント処理

ボタンのcommand引数でクリックイベントを、bind('')でEnterキーイベントを処理します。どちらの操作でも同じprocess()が呼ばれ、コードの重複を避けられます。

import tkinter as tk
from tkinter import ttk, messagebox, filedialog
import csv
import os
import io
from collections import defaultdict


class App056:
    """CSVデータクリーナー"""

    def __init__(self, root):
        self.root = root
        self.root.title("CSVデータクリーナー")
        self.root.geometry("1000x620")
        self.root.configure(bg="#1e1e1e")
        self._original = []
        self._cleaned = []
        self._headers = []
        self._build_ui()

    def _build_ui(self):
        header = tk.Frame(self.root, bg="#252526", pady=6)
        header.pack(fill=tk.X)
        tk.Label(header, text="🧹 CSVデータクリーナー",
                 font=("Noto Sans JP", 12, "bold"),
                 bg="#252526", fg="#4fc3f7").pack(side=tk.LEFT, padx=12)

        # ツールバー
        tb = tk.Frame(self.root, bg="#2d2d2d", pady=4)
        tb.pack(fill=tk.X)
        ttk.Button(tb, text="📂 CSV読込",    command=self._load).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="▶ クリーン実行", command=self._clean).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="💾 保存",        command=self._save).pack(side=tk.LEFT, padx=4)

        # オプションパネル
        opt_f = tk.LabelFrame(self.root, text="クリーンオプション",
                               bg="#252526", fg="#ccc", font=("Arial", 9),
                               padx=8, pady=4)
        opt_f.pack(fill=tk.X, padx=8, pady=4)

        self.opt_empty_row  = tk.BooleanVar(value=True)
        self.opt_dup_row    = tk.BooleanVar(value=True)
        self.opt_trim       = tk.BooleanVar(value=True)
        self.opt_empty_col  = tk.BooleanVar(value=False)
        self.opt_lower_hdr  = tk.BooleanVar(value=False)
        self.opt_fill_empty = tk.BooleanVar(value=False)
        self.fill_val_var   = tk.StringVar(value="")

        opts = [
            ("空行を削除",         self.opt_empty_row),
            ("重複行を削除",       self.opt_dup_row),
            ("前後の空白を除去",   self.opt_trim),
            ("空列を削除",         self.opt_empty_col),
            ("ヘッダーを小文字に", self.opt_lower_hdr),
            ("空セルを埋める",     self.opt_fill_empty),
        ]
        for i, (label, var) in enumerate(opts):
            tk.Checkbutton(opt_f, text=label, variable=var,
                           bg="#252526", fg="#ccc", selectcolor="#3c3c3c",
                           activebackground="#252526",
                           font=("Arial", 9)).grid(
                row=i//3, column=i%3*2, sticky="w", padx=6)

        tk.Label(opt_f, text="埋める値:", bg="#252526", fg="#ccc",
                 font=("Arial", 9)).grid(row=1, column=4, sticky="w")
        ttk.Entry(opt_f, textvariable=self.fill_val_var,
                  width=10).grid(row=1, column=5, sticky="w")

        # 左右プレビュー
        paned = ttk.PanedWindow(self.root, orient=tk.HORIZONTAL)
        paned.pack(fill=tk.BOTH, expand=True, padx=8, pady=4)

        left = tk.Frame(paned, bg="#1e1e1e")
        paned.add(left, weight=1)
        tk.Label(left, text="元データ", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.orig_tree = self._make_tree(left)

        right = tk.Frame(paned, bg="#1e1e1e")
        paned.add(right, weight=1)
        tk.Label(right, text="クリーン後", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.clean_tree = self._make_tree(right)

        self.status_var = tk.StringVar(value="CSVファイルを読み込んでください")
        tk.Label(self.root, textvariable=self.status_var,
                 bg="#252526", fg="#858585", font=("Arial", 9),
                 anchor="w", padx=8).pack(fill=tk.X, side=tk.BOTTOM)

    def _make_tree(self, parent):
        frame = tk.Frame(parent, bg="#1e1e1e")
        frame.pack(fill=tk.BOTH, expand=True)
        tree = ttk.Treeview(frame, show="headings", selectmode="browse")
        sbx = ttk.Scrollbar(frame, orient=tk.HORIZONTAL, command=tree.xview)
        sby = ttk.Scrollbar(frame, command=tree.yview)
        tree.configure(xscrollcommand=sbx.set, yscrollcommand=sby.set)
        sby.pack(side=tk.RIGHT, fill=tk.Y)
        tree.pack(fill=tk.BOTH, expand=True)
        sbx.pack(fill=tk.X)
        return tree

    def _load(self):
        path = filedialog.askopenfilename(
            filetypes=[("CSV", "*.csv"), ("TSV", "*.tsv"), ("すべて", "*.*")])
        if not path:
            return
        try:
            enc = "utf-8-sig"
            with open(path, encoding=enc, errors="replace") as f:
                reader = csv.reader(f)
                rows = list(reader)
            if not rows:
                messagebox.showinfo("情報", "データが空です")
                return
            self._headers = rows[0]
            self._original = rows[1:]
            self._cleaned = list(self._original)
            self._show_tree(self.orig_tree, self._headers, self._original)
            self._show_tree(self.clean_tree, self._headers, self._cleaned)
            self.status_var.set(
                f"読込完了: {len(self._original)} 行 × {len(self._headers)} 列")
        except Exception as e:
            messagebox.showerror("エラー", str(e))

    def _show_tree(self, tree, headers, rows, max_rows=500):
        cols = [f"c{i}" for i in range(len(headers))]
        tree.configure(columns=cols)
        for i, h in enumerate(headers):
            tree.heading(f"c{i}", text=str(h))
            tree.column(f"c{i}", width=100, anchor="w")
        tree.delete(*tree.get_children())
        for row in rows[:max_rows]:
            tree.insert("", tk.END, values=row)

    def _clean(self):
        if not self._original and not self._headers:
            messagebox.showwarning("警告", "CSVを読み込んでください")
            return

        rows = [list(r) for r in self._original]
        headers = list(self._headers)

        # 前後空白除去
        if self.opt_trim.get():
            rows = [[c.strip() for c in r] for r in rows]
            headers = [h.strip() for h in headers]

        # ヘッダー小文字化
        if self.opt_lower_hdr.get():
            headers = [h.lower() for h in headers]

        # 空セルを埋める
        if self.opt_fill_empty.get():
            fill_val = self.fill_val_var.get()
            rows = [[c if c != "" else fill_val for c in r] for r in rows]

        # 空行削除
        if self.opt_empty_row.get():
            rows = [r for r in rows if any(c.strip() for c in r)]

        # 重複行削除
        if self.opt_dup_row.get():
            seen = set()
            unique = []
            for r in rows:
                key = tuple(r)
                if key not in seen:
                    seen.add(key)
                    unique.append(r)
            rows = unique

        # 空列削除
        if self.opt_empty_col.get() and rows:
            non_empty_cols = []
            for j in range(len(headers)):
                if any(j < len(r) and r[j].strip() for r in rows):
                    non_empty_cols.append(j)
            headers = [headers[j] for j in non_empty_cols]
            rows = [[r[j] if j < len(r) else "" for j in non_empty_cols]
                    for r in rows]

        self._cleaned = rows
        self._show_tree(self.clean_tree, headers, rows)
        removed = len(self._original) - len(rows)
        self.status_var.set(
            f"クリーン完了: {len(rows)} 行 (元 {len(self._original)} 行, "
            f"{removed} 行削除)")

    def _save(self):
        if not self._cleaned and not self._headers:
            messagebox.showwarning("警告", "データがありません")
            return
        path = filedialog.asksaveasfilename(
            defaultextension=".csv",
            filetypes=[("CSV", "*.csv")])
        if not path:
            return
        try:
            with open(path, "w", newline="", encoding="utf-8-sig") as f:
                writer = csv.writer(f)
                writer.writerow(self._headers)
                writer.writerows(self._cleaned)
            messagebox.showinfo("完了",
                                 f"{len(self._cleaned)} 行を保存しました:\n{path}")
            self.status_var.set(f"保存完了: {os.path.basename(path)}")
        except Exception as e:
            messagebox.showerror("エラー", str(e))


if __name__ == "__main__":
    root = tk.Tk()
    app = App056(root)
    root.mainloop()

Textウィジェットでの結果表示

tk.Textウィジェットをstate=DISABLED（読み取り専用）で作成し、更新時はNORMALに変更してinsert()で内容を書き込み、再びDISABLEDに戻します。

import tkinter as tk
from tkinter import ttk, messagebox, filedialog
import csv
import os
import io
from collections import defaultdict


class App056:
    """CSVデータクリーナー"""

    def __init__(self, root):
        self.root = root
        self.root.title("CSVデータクリーナー")
        self.root.geometry("1000x620")
        self.root.configure(bg="#1e1e1e")
        self._original = []
        self._cleaned = []
        self._headers = []
        self._build_ui()

    def _build_ui(self):
        header = tk.Frame(self.root, bg="#252526", pady=6)
        header.pack(fill=tk.X)
        tk.Label(header, text="🧹 CSVデータクリーナー",
                 font=("Noto Sans JP", 12, "bold"),
                 bg="#252526", fg="#4fc3f7").pack(side=tk.LEFT, padx=12)

        # ツールバー
        tb = tk.Frame(self.root, bg="#2d2d2d", pady=4)
        tb.pack(fill=tk.X)
        ttk.Button(tb, text="📂 CSV読込",    command=self._load).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="▶ クリーン実行", command=self._clean).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="💾 保存",        command=self._save).pack(side=tk.LEFT, padx=4)

        # オプションパネル
        opt_f = tk.LabelFrame(self.root, text="クリーンオプション",
                               bg="#252526", fg="#ccc", font=("Arial", 9),
                               padx=8, pady=4)
        opt_f.pack(fill=tk.X, padx=8, pady=4)

        self.opt_empty_row  = tk.BooleanVar(value=True)
        self.opt_dup_row    = tk.BooleanVar(value=True)
        self.opt_trim       = tk.BooleanVar(value=True)
        self.opt_empty_col  = tk.BooleanVar(value=False)
        self.opt_lower_hdr  = tk.BooleanVar(value=False)
        self.opt_fill_empty = tk.BooleanVar(value=False)
        self.fill_val_var   = tk.StringVar(value="")

        opts = [
            ("空行を削除",         self.opt_empty_row),
            ("重複行を削除",       self.opt_dup_row),
            ("前後の空白を除去",   self.opt_trim),
            ("空列を削除",         self.opt_empty_col),
            ("ヘッダーを小文字に", self.opt_lower_hdr),
            ("空セルを埋める",     self.opt_fill_empty),
        ]
        for i, (label, var) in enumerate(opts):
            tk.Checkbutton(opt_f, text=label, variable=var,
                           bg="#252526", fg="#ccc", selectcolor="#3c3c3c",
                           activebackground="#252526",
                           font=("Arial", 9)).grid(
                row=i//3, column=i%3*2, sticky="w", padx=6)

        tk.Label(opt_f, text="埋める値:", bg="#252526", fg="#ccc",
                 font=("Arial", 9)).grid(row=1, column=4, sticky="w")
        ttk.Entry(opt_f, textvariable=self.fill_val_var,
                  width=10).grid(row=1, column=5, sticky="w")

        # 左右プレビュー
        paned = ttk.PanedWindow(self.root, orient=tk.HORIZONTAL)
        paned.pack(fill=tk.BOTH, expand=True, padx=8, pady=4)

        left = tk.Frame(paned, bg="#1e1e1e")
        paned.add(left, weight=1)
        tk.Label(left, text="元データ", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.orig_tree = self._make_tree(left)

        right = tk.Frame(paned, bg="#1e1e1e")
        paned.add(right, weight=1)
        tk.Label(right, text="クリーン後", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.clean_tree = self._make_tree(right)

        self.status_var = tk.StringVar(value="CSVファイルを読み込んでください")
        tk.Label(self.root, textvariable=self.status_var,
                 bg="#252526", fg="#858585", font=("Arial", 9),
                 anchor="w", padx=8).pack(fill=tk.X, side=tk.BOTTOM)

    def _make_tree(self, parent):
        frame = tk.Frame(parent, bg="#1e1e1e")
        frame.pack(fill=tk.BOTH, expand=True)
        tree = ttk.Treeview(frame, show="headings", selectmode="browse")
        sbx = ttk.Scrollbar(frame, orient=tk.HORIZONTAL, command=tree.xview)
        sby = ttk.Scrollbar(frame, command=tree.yview)
        tree.configure(xscrollcommand=sbx.set, yscrollcommand=sby.set)
        sby.pack(side=tk.RIGHT, fill=tk.Y)
        tree.pack(fill=tk.BOTH, expand=True)
        sbx.pack(fill=tk.X)
        return tree

    def _load(self):
        path = filedialog.askopenfilename(
            filetypes=[("CSV", "*.csv"), ("TSV", "*.tsv"), ("すべて", "*.*")])
        if not path:
            return
        try:
            enc = "utf-8-sig"
            with open(path, encoding=enc, errors="replace") as f:
                reader = csv.reader(f)
                rows = list(reader)
            if not rows:
                messagebox.showinfo("情報", "データが空です")
                return
            self._headers = rows[0]
            self._original = rows[1:]
            self._cleaned = list(self._original)
            self._show_tree(self.orig_tree, self._headers, self._original)
            self._show_tree(self.clean_tree, self._headers, self._cleaned)
            self.status_var.set(
                f"読込完了: {len(self._original)} 行 × {len(self._headers)} 列")
        except Exception as e:
            messagebox.showerror("エラー", str(e))

    def _show_tree(self, tree, headers, rows, max_rows=500):
        cols = [f"c{i}" for i in range(len(headers))]
        tree.configure(columns=cols)
        for i, h in enumerate(headers):
            tree.heading(f"c{i}", text=str(h))
            tree.column(f"c{i}", width=100, anchor="w")
        tree.delete(*tree.get_children())
        for row in rows[:max_rows]:
            tree.insert("", tk.END, values=row)

    def _clean(self):
        if not self._original and not self._headers:
            messagebox.showwarning("警告", "CSVを読み込んでください")
            return

        rows = [list(r) for r in self._original]
        headers = list(self._headers)

        # 前後空白除去
        if self.opt_trim.get():
            rows = [[c.strip() for c in r] for r in rows]
            headers = [h.strip() for h in headers]

        # ヘッダー小文字化
        if self.opt_lower_hdr.get():
            headers = [h.lower() for h in headers]

        # 空セルを埋める
        if self.opt_fill_empty.get():
            fill_val = self.fill_val_var.get()
            rows = [[c if c != "" else fill_val for c in r] for r in rows]

        # 空行削除
        if self.opt_empty_row.get():
            rows = [r for r in rows if any(c.strip() for c in r)]

        # 重複行削除
        if self.opt_dup_row.get():
            seen = set()
            unique = []
            for r in rows:
                key = tuple(r)
                if key not in seen:
                    seen.add(key)
                    unique.append(r)
            rows = unique

        # 空列削除
        if self.opt_empty_col.get() and rows:
            non_empty_cols = []
            for j in range(len(headers)):
                if any(j < len(r) and r[j].strip() for r in rows):
                    non_empty_cols.append(j)
            headers = [headers[j] for j in non_empty_cols]
            rows = [[r[j] if j < len(r) else "" for j in non_empty_cols]
                    for r in rows]

        self._cleaned = rows
        self._show_tree(self.clean_tree, headers, rows)
        removed = len(self._original) - len(rows)
        self.status_var.set(
            f"クリーン完了: {len(rows)} 行 (元 {len(self._original)} 行, "
            f"{removed} 行削除)")

    def _save(self):
        if not self._cleaned and not self._headers:
            messagebox.showwarning("警告", "データがありません")
            return
        path = filedialog.asksaveasfilename(
            defaultextension=".csv",
            filetypes=[("CSV", "*.csv")])
        if not path:
            return
        try:
            with open(path, "w", newline="", encoding="utf-8-sig") as f:
                writer = csv.writer(f)
                writer.writerow(self._headers)
                writer.writerows(self._cleaned)
            messagebox.showinfo("完了",
                                 f"{len(self._cleaned)} 行を保存しました:\n{path}")
            self.status_var.set(f"保存完了: {os.path.basename(path)}")
        except Exception as e:
            messagebox.showerror("エラー", str(e))


if __name__ == "__main__":
    root = tk.Tk()
    app = App056(root)
    root.mainloop()

例外処理とエラーハンドリング

try-exceptでValueErrorとExceptionを捕捉し、messagebox.showerror()でエラーメッセージを表示します。予期しないエラーも処理することで、アプリの堅牢性が向上します。

import tkinter as tk
from tkinter import ttk, messagebox, filedialog
import csv
import os
import io
from collections import defaultdict


class App056:
    """CSVデータクリーナー"""

    def __init__(self, root):
        self.root = root
        self.root.title("CSVデータクリーナー")
        self.root.geometry("1000x620")
        self.root.configure(bg="#1e1e1e")
        self._original = []
        self._cleaned = []
        self._headers = []
        self._build_ui()

    def _build_ui(self):
        header = tk.Frame(self.root, bg="#252526", pady=6)
        header.pack(fill=tk.X)
        tk.Label(header, text="🧹 CSVデータクリーナー",
                 font=("Noto Sans JP", 12, "bold"),
                 bg="#252526", fg="#4fc3f7").pack(side=tk.LEFT, padx=12)

        # ツールバー
        tb = tk.Frame(self.root, bg="#2d2d2d", pady=4)
        tb.pack(fill=tk.X)
        ttk.Button(tb, text="📂 CSV読込",    command=self._load).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="▶ クリーン実行", command=self._clean).pack(side=tk.LEFT, padx=4)
        ttk.Button(tb, text="💾 保存",        command=self._save).pack(side=tk.LEFT, padx=4)

        # オプションパネル
        opt_f = tk.LabelFrame(self.root, text="クリーンオプション",
                               bg="#252526", fg="#ccc", font=("Arial", 9),
                               padx=8, pady=4)
        opt_f.pack(fill=tk.X, padx=8, pady=4)

        self.opt_empty_row  = tk.BooleanVar(value=True)
        self.opt_dup_row    = tk.BooleanVar(value=True)
        self.opt_trim       = tk.BooleanVar(value=True)
        self.opt_empty_col  = tk.BooleanVar(value=False)
        self.opt_lower_hdr  = tk.BooleanVar(value=False)
        self.opt_fill_empty = tk.BooleanVar(value=False)
        self.fill_val_var   = tk.StringVar(value="")

        opts = [
            ("空行を削除",         self.opt_empty_row),
            ("重複行を削除",       self.opt_dup_row),
            ("前後の空白を除去",   self.opt_trim),
            ("空列を削除",         self.opt_empty_col),
            ("ヘッダーを小文字に", self.opt_lower_hdr),
            ("空セルを埋める",     self.opt_fill_empty),
        ]
        for i, (label, var) in enumerate(opts):
            tk.Checkbutton(opt_f, text=label, variable=var,
                           bg="#252526", fg="#ccc", selectcolor="#3c3c3c",
                           activebackground="#252526",
                           font=("Arial", 9)).grid(
                row=i//3, column=i%3*2, sticky="w", padx=6)

        tk.Label(opt_f, text="埋める値:", bg="#252526", fg="#ccc",
                 font=("Arial", 9)).grid(row=1, column=4, sticky="w")
        ttk.Entry(opt_f, textvariable=self.fill_val_var,
                  width=10).grid(row=1, column=5, sticky="w")

        # 左右プレビュー
        paned = ttk.PanedWindow(self.root, orient=tk.HORIZONTAL)
        paned.pack(fill=tk.BOTH, expand=True, padx=8, pady=4)

        left = tk.Frame(paned, bg="#1e1e1e")
        paned.add(left, weight=1)
        tk.Label(left, text="元データ", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.orig_tree = self._make_tree(left)

        right = tk.Frame(paned, bg="#1e1e1e")
        paned.add(right, weight=1)
        tk.Label(right, text="クリーン後", bg="#1e1e1e", fg="#888",
                 font=("Arial", 9)).pack(anchor="w")
        self.clean_tree = self._make_tree(right)

        self.status_var = tk.StringVar(value="CSVファイルを読み込んでください")
        tk.Label(self.root, textvariable=self.status_var,
                 bg="#252526", fg="#858585", font=("Arial", 9),
                 anchor="w", padx=8).pack(fill=tk.X, side=tk.BOTTOM)

    def _make_tree(self, parent):
        frame = tk.Frame(parent, bg="#1e1e1e")
        frame.pack(fill=tk.BOTH, expand=True)
        tree = ttk.Treeview(frame, show="headings", selectmode="browse")
        sbx = ttk.Scrollbar(frame, orient=tk.HORIZONTAL, command=tree.xview)
        sby = ttk.Scrollbar(frame, command=tree.yview)
        tree.configure(xscrollcommand=sbx.set, yscrollcommand=sby.set)
        sby.pack(side=tk.RIGHT, fill=tk.Y)
        tree.pack(fill=tk.BOTH, expand=True)
        sbx.pack(fill=tk.X)
        return tree

    def _load(self):
        path = filedialog.askopenfilename(
            filetypes=[("CSV", "*.csv"), ("TSV", "*.tsv"), ("すべて", "*.*")])
        if not path:
            return
        try:
            enc = "utf-8-sig"
            with open(path, encoding=enc, errors="replace") as f:
                reader = csv.reader(f)
                rows = list(reader)
            if not rows:
                messagebox.showinfo("情報", "データが空です")
                return
            self._headers = rows[0]
            self._original = rows[1:]
            self._cleaned = list(self._original)
            self._show_tree(self.orig_tree, self._headers, self._original)
            self._show_tree(self.clean_tree, self._headers, self._cleaned)
            self.status_var.set(
                f"読込完了: {len(self._original)} 行 × {len(self._headers)} 列")
        except Exception as e:
            messagebox.showerror("エラー", str(e))

    def _show_tree(self, tree, headers, rows, max_rows=500):
        cols = [f"c{i}" for i in range(len(headers))]
        tree.configure(columns=cols)
        for i, h in enumerate(headers):
            tree.heading(f"c{i}", text=str(h))
            tree.column(f"c{i}", width=100, anchor="w")
        tree.delete(*tree.get_children())
        for row in rows[:max_rows]:
            tree.insert("", tk.END, values=row)

    def _clean(self):
        if not self._original and not self._headers:
            messagebox.showwarning("警告", "CSVを読み込んでください")
            return

        rows = [list(r) for r in self._original]
        headers = list(self._headers)

        # 前後空白除去
        if self.opt_trim.get():
            rows = [[c.strip() for c in r] for r in rows]
            headers = [h.strip() for h in headers]

        # ヘッダー小文字化
        if self.opt_lower_hdr.get():
            headers = [h.lower() for h in headers]

        # 空セルを埋める
        if self.opt_fill_empty.get():
            fill_val = self.fill_val_var.get()
            rows = [[c if c != "" else fill_val for c in r] for r in rows]

        # 空行削除
        if self.opt_empty_row.get():
            rows = [r for r in rows if any(c.strip() for c in r)]

        # 重複行削除
        if self.opt_dup_row.get():
            seen = set()
            unique = []
            for r in rows:
                key = tuple(r)
                if key not in seen:
                    seen.add(key)
                    unique.append(r)
            rows = unique

        # 空列削除
        if self.opt_empty_col.get() and rows:
            non_empty_cols = []
            for j in range(len(headers)):
                if any(j < len(r) and r[j].strip() for r in rows):
                    non_empty_cols.append(j)
            headers = [headers[j] for j in non_empty_cols]
            rows = [[r[j] if j < len(r) else "" for j in non_empty_cols]
                    for r in rows]

        self._cleaned = rows
        self._show_tree(self.clean_tree, headers, rows)
        removed = len(self._original) - len(rows)
        self.status_var.set(
            f"クリーン完了: {len(rows)} 行 (元 {len(self._original)} 行, "
            f"{removed} 行削除)")

    def _save(self):
        if not self._cleaned and not self._headers:
            messagebox.showwarning("警告", "データがありません")
            return
        path = filedialog.asksaveasfilename(
            defaultextension=".csv",
            filetypes=[("CSV", "*.csv")])
        if not path:
            return
        try:
            with open(path, "w", newline="", encoding="utf-8-sig") as f:
                writer = csv.writer(f)
                writer.writerow(self._headers)
                writer.writerows(self._cleaned)
            messagebox.showinfo("完了",
                                 f"{len(self._cleaned)} 行を保存しました:\n{path}")
            self.status_var.set(f"保存完了: {os.path.basename(path)}")
        except Exception as e:
            messagebox.showerror("エラー", str(e))


if __name__ == "__main__":
    root = tk.Tk()
    app = App056(root)
    root.mainloop()

💡 ダークモードを追加する

bg色・fg色を辞書で管理し、ボタン1つでダークモード・ライトモードを切り替えられるようにしましょう。

💡 データの保存機能

処理結果をCSV・TXTファイルに保存する機能を追加しましょう。filedialog.asksaveasfilename()でファイル保存ダイアログが使えます。

💡 設定ダイアログ

フォントサイズや色などの設定をユーザーが変更できるオプションダイアログを追加しましょう。

❌ 日本語フォントが表示されない

原因：システムに日本語フォントが見つからない場合があります。

解決法：font引数を省略するかシステムに合ったフォントを指定してください。

❌ ライブラリのインポートエラー

原因：必要なライブラリがインストールされていません。

解決法：pip install コマンドで必要なライブラリをインストールしてください。 (pip install pandas)

❌ ウィンドウサイズが合わない

原因：画面解像度や表示スケールによって異なる場合があります。

解決法：root.geometry()で適切なサイズに調整してください。