Qt（九）文件夹与文件（显示图像）_qt 文件夹图片

一、UI布局

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QFileDialog>
#include <QTreeWidgetItem>
#include <QTreeWidget>
#include <QPixmap>
#include <QLabel>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT
private:
    enum treeItemType {itTopItem=1001,itGroupItem,itImageItem};
    enum treeColNum {colItem=0,colItemType=1};
    QPixmap pixmap;
    QLabel  labFileName;
    float pixRatio;

    void changeItemCaption(QTreeWidgetItem *item);
public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void on_actOpenFolder_triggered();

    void on_actOpenFile_triggered();

    void on_treeWidget_currentItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *previous);

    void on_actWidth_triggered();

    void on_actIter_triggered();

    void on_actDel_triggered();

    void on_actHeight_triggered();

    void on_actZoomIn_triggered();

    void on_actZoomOut_triggered();

    void on_actRealSize_triggered();

private:
    Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"


MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->statusbar->addWidget(&labFileName);
}

MainWindow::~MainWindow()
{
    delete ui;
}


void MainWindow::on_actOpenFolder_triggered()
{
    QString fullname = QFileDialog::getExistingDirectory(this,"open Folder",".");
    if(fullname.isEmpty()) return;

    QString dir = fullname.right(fullname.length()-fullname.lastIndexOf('/')-1);

    if(!ui->treeWidget->currentIndex().isValid()) return;
    QTreeWidgetItem* parItem = ui->treeWidget->currentItem();
    QTreeWidgetItem* item = new QTreeWidgetItem(itGroupItem);

    QIcon icon(":/images/icon/open.ico");
    item->setIcon(treeColNum::colItem, icon);
    item->setText(treeColNum::colItem, dir);
    item->setText(treeColNum::colItemType, "type:group");
    item->setFlags(Qt::ItemIsSelectable|Qt::ItemIsAutoTristate|Qt::ItemIsEnabled|Qt::ItemIsUserCheckable);
    item->setCheckState(colItem,Qt::Checked);
    parItem->addChild(item);

}

void MainWindow::on_actOpenFile_triggered()
{
    QStringList files = QFileDialog::getOpenFileNames(this,"file or files",".","Images(*.jpg *.png)");
    if (files.isEmpty()) return;

    QTreeWidgetItem* parItem;
    QTreeWidgetItem* item = ui->treeWidget->currentItem();

    if(item->type() == treeItemType::itImageItem)
        parItem = item->parent();
    else
        parItem = item;
    foreach(auto &file, files){
        item = new QTreeWidgetItem(treeItemType::itImageItem);
        QString name = file.right(file.length()-file.lastIndexOf('/')-1);
        QIcon icon(":/images/icon/picture.ico");
        item->setIcon(treeColNum::colItem, icon);
        item->setText(treeColNum::colItem, name);
        item->setText(treeColNum::colItemType, "type:Image");
        item->setFlags(Qt::ItemIsSelectable|Qt::ItemIsAutoTristate|Qt::ItemIsEnabled|Qt::ItemIsUserCheckable);
        item->setCheckState(colItem,Qt::Checked);
        item->setData(treeColNum::colItem,Qt::UserRole,file);
        parItem->addChild(item);
    }

}

void MainWindow::on_treeWidget_currentItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *previous)
{
    Q_UNUSED(previous);
    if(current == NULL) return;
    int var = current->type();
    switch (var) {
    case treeItemType::itTopItem:
        ui->actOpenFile->setEnabled(true);
        ui->actOpenFolder->setEnabled(true);
        ui->actDel->setEnabled(false);
        break;
    case treeItemType::itGroupItem:
        ui->actOpenFile->setEnabled(true);
        ui->actOpenFolder->setEnabled(true);
        ui->actDel->setEnabled(true);
        break;
    case treeItemType::itImageItem:
        ui->actOpenFile->setEnabled(true);
        ui->actOpenFolder->setEnabled(false);
        ui->actDel->setEnabled(true);
        labFileName.setText(current->data(colItem,Qt::UserRole).toString());
        pixmap.load(current->data(colItem,Qt::UserRole).toString());
        on_actWidth_triggered();
        ui->actWidth->setEnabled(true);
        ui->actHeight->setEnabled(true);
        ui->actZoomIn->setEnabled(true);
        ui->actZoomOut->setEnabled(true);
        ui->actRealSize->setEnabled(true);
        break;
    }
}

void MainWindow::on_actWidth_triggered()
{
    int W = ui->scrollArea->width();
    int realW = pixmap.width();
    pixRatio = (float)W/realW;
    QPixmap pix = pixmap.scaledToWidth(W-30);
    ui->label->setPixmap(pix);

}

void MainWindow::on_actIter_triggered()
{
    for (int i=0; i<ui->treeWidget->topLevelItemCount(); i++) {
        QTreeWidgetItem *item = ui->treeWidget->topLevelItem(i);
        changeItemCaption(item);
    }
}

void MainWindow::changeItemCaption(QTreeWidgetItem *item)
{
    QString str = "x_"+item->text(colItem);
    item->setText(colItem,str);
    for (int i=0; i<item->childCount(); i++) {
        changeItemCaption(item->child(i));
    }
}


void MainWindow::on_actDel_triggered()
{
    QTreeWidgetItem* item = ui->treeWidget->currentItem();
    if (!item->parent()) {
        ui->actDel->setEnabled(false);
        return;
    }
    QTreeWidgetItem* ParItem = item->parent();
    ParItem->removeChild(item);
    delete item;
}

void MainWindow::on_actHeight_triggered()
{
    int H = ui->scrollArea->height();
    int realH = pixmap.height();
    pixRatio = (float)H/realH;
    QPixmap pix = pixmap.scaledToHeight(H-30);
    ui->label->setPixmap(pix);
}

void MainWindow::on_actZoomIn_triggered()
{
    pixRatio *= 1.2;
    int w = pixRatio*pixmap.width();
    int h = pixRatio*pixmap.height();
    QPixmap pix = pixmap.scaled(w,h);
    ui->label->setPixmap(pix);

}

void MainWindow::on_actZoomOut_triggered()
{
    pixRatio *= 0.8;
    int w = pixRatio*pixmap.width();
    int h = pixRatio*pixmap.height();
    QPixmap pix = pixmap.scaled(w,h);
    ui->label->setPixmap(pix);
}

void MainWindow::on_actRealSize_triggered()
{
    ui->label->setPixmap(pixmap);
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171

二、效果演示