效果：

1. 初始显示

2. 更换组件，在本例中是将原有组件都清空重新创建组件放入

代码：

import sys
from PyQt5 import QtCore,QtGui,QtWidgets

class ExampleWidget(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()
        self.temp_mark = 0
        self.init_data()
        self.init_ui()
        self.fill_pic_widget()
    def init_data(self):
        self.pic_file_name_list = ['000', '001', '002', '003', '004', '005', '006', '007', '008', '009', '010', '011',
                                   '012', '013', '014', '015', '016', '017']
        pass
    def init_ui(self):
        self.setWindowTitle('QScrollArea动态放置控件例子')
        one_btn = QtWidgets.QPushButton('换内容')
        one_btn.clicked.connect(self.one_btn_clicked)

        self.pic_layout = QtWidgets.QGridLayout()

        self.scroll_area = QtWidgets.QScrollArea()
        self.scroll_area.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)

        layout = QtWidgets.QVBoxLayout()
        layout.addWidget(one_btn)
        layout.addWidget(self.scroll_area)
        self.setLayout(layout)
        pass
    def one_btn_clicked(self):
        self.temp_mark = 1
        self.fill_pic_widget()
        pass
    def fill_pic_widget(self):
        '''放置图片'''
        # 清空控件
        while self.pic_layout.count():
            item = self.pic_layout.takeAt(0)
            widget = item.widget()
            if widget is not None:
                widget.deleteLater()
                pass
            pass
        sc_child_widget = self.scroll_area.takeWidget()
        if sc_child_widget is not None:
            sc_child_widget.deleteLater()
        pre_dir = r'E:/temp005/'
        row_i = -2
        if self.temp_mark == 1:
            self.pic_file_name_list.reverse()
        for pic_index,file_name in enumerate(self.pic_file_name_list):
            one_check = QtWidgets.QCheckBox(file_name)
            pixmap = QtGui.QPixmap(pre_dir + file_name + '.jpeg')
            one_piclabel = QtWidgets.QLabel()
            one_piclabel.setPixmap(pixmap)
            one_piclabel.setScaledContents(True)

            col_i = pic_index%4
            if col_i == 0:
                row_i +=2
            print(file_name, row_i, col_i)
            self.pic_layout.addWidget(one_check,row_i,col_i,1,1)
            self.pic_layout.addWidget(one_piclabel,row_i+1,col_i,1,1)
            pass
        print('self.pic_layout,',self.pic_layout.count())
        one_sc_child_widget = QtWidgets.QWidget()
        one_sc_child_widget.setLayout(self.pic_layout)
        self.scroll_area.setWidget(one_sc_child_widget)
        pass

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    t_win = ExampleWidget()
    t_win.show()
    sys.exit(app.exec_())
    pass