如何使Button和其他小部件不透明？

Question

所以我一直在努力为Qt设计器设置背景。

我发现了如何设置背景图像，并遇到另一个问题，似乎我拥有的每个小部件都是透明的，您看不到任何小部件，通常它们是白色的，并且idk如何设置

我的.ui代码：

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Dialog</class>
 <widget class="QDialog" name="Dialog">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>500</width>
    <height>400</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Dialog</string>
  </property>
  <property name="styleSheet">
   <string notr="true">background-image: url(:/img/Programming/Eclipse/Encrypter and Decrypter/Images/matrix.png);</string>
  </property>
  <widget class="QPushButton" name="pushbutton">
   <property name="geometry">
    <rect>
     <x>140</x>
     <y>310</y>
     <width>75</width>
     <height>31</height>
    </rect>
   </property>
   <property name="font">
    <font>
     <family>Arial</family>
     <pointsize>10</pointsize>
    </font>
   </property>
   <property name="text">
    <string>Encrypt</string>
   </property>
   <property name="default">
    <bool>false</bool>
   </property>
   <property name="flat">
    <bool>false</bool>
   </property>
  </widget>
  <widget class="QPushButton" name="pushButton">
   <property name="geometry">
    <rect>
     <x>280</x>
     <y>310</y>
     <width>75</width>
     <height>31</height>
    </rect>
   </property>
   <property name="font">
    <font>
     <family>Arial</family>
     <pointsize>10</pointsize>
    </font>
   </property>
   <property name="styleSheet">
    <string notr="true"/>
   </property>
   <property name="text">
    <string>Decrypt</string>
   </property>
  </widget>
  <widget class="QTextEdit" name="textEdit">
   <property name="geometry">
    <rect>
     <x>30</x>
     <y>80</y>
     <width>201</width>
     <height>201</height>
    </rect>
   </property>
   <property name="toolTip">
    <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Input your text here&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
   </property>
  </widget>
  <zorder>pushButton</zorder>
  <zorder>pushbutton</zorder>
  <zorder>textEdit</zorder>
 </widget>
 <resources>
  <include location="resource.qrc"/>
 </resources>
 <connections/>
</ui>