Basic4android（B4A）设置主题样式

    android:theme="@android:style/Theme.Dialog" : Activity显示为对话框模式
    android:theme="@android:style/Theme.NoTitleBar" : 不显示应用程序标题栏
    android:theme="@android:style/Theme.NoTitleBar.Fullscreen" : 不显示应用程序标题栏，并全屏
    android:theme="Theme.Light ": 背景为白色
    android:theme="Theme.Light.NoTitleBar" : 白色背景并无标题栏
    android:theme="Theme.Light.NoTitleBar.Fullscreen" : 白色背景，无标题栏，全屏
    android:theme="Theme.Black" : 背景黑色
    android:theme="Theme.Black.NoTitleBar" : 黑色背景并无标题栏
    android:theme="Theme.Black.NoTitleBar.Fullscreen" : 黑色背景，无标题栏，全屏
    android:theme="Theme.Wallpaper" : 用系统桌面为应用程序背景
    android:theme="Theme.Wallpaper.NoTitleBar" : 用系统桌面为应用程序背景，且无标题栏
    android:theme="Theme.Wallpaper.NoTitleBar.Fullscreen" : 用系统桌面为应用程序背景，无标题栏，全屏
    android:theme="Theme.Translucent : 透明背景
    android:theme="Theme.Translucent.NoTitleBar" : 透明背景并无标题
    android:theme="Theme.Translucent.NoTitleBar.Fullscreen" : 透明背景并无标题，全屏
    android:theme="Theme.Panel ": 面板风格显示
    android:theme="Theme.Light.Panel" : 平板风格显示

      #Region  Project Attributes
          #ApplicationLabel: B4A_主题设置
          #VersionCode: 1
          #VersionName:
          #SupportedOrientations: unspecified
          #CanInstallToExternalStorage: False
      #End Region

      #Region  Activity Attributes
          #FullScreen: False
          #IncludeTitle: True
      #End Region

      Sub Process_Globals
          Private Theme_Value As Int
      End Sub

      Sub Globals
          Private res As XmlLayoutBuilder
          Private ProgressBar1 As ProgressBar
          Private Spinner1 As Spinner
      End Sub

      Sub Activity_Create(FirstTime As Boolean)
          Activity.LoadLayout("main")
          ProgressBar1.Progress = 50
          Spinner1.AddAll(Array("Item 1", "Item 2", "Item 3"))
      End Sub

      Sub btnHolo_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Holo"))
      End Sub

      Sub btnHoloLight_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Holo.Light"))
      End Sub

      Sub btnHoloLightDark_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Holo.Light.DarkActionBar"))
      End Sub

      Sub btnOld_Click
          SetTheme(16973829)
      End Sub

      Sub btnMaterialLightDark_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Material.Light.DarkActionBar"))
      End Sub

      Sub btnMaterialLight_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Material.Light"))
      End Sub

      Sub btnMaterial_Click
          SetTheme(res.GetResourceId("style", "android:style/Theme.Material"))
      End Sub

      Private Sub SetTheme (Theme As Int)
          If Theme = 0 Then
              ToastMessageShow("Theme not available.", False)
              Return
          End If
          If Theme = Theme_Value Then Return
          File.WriteString(File.DirInternal, "theme.txt", Theme)
          Theme_Value = Theme
          Activity.Finish
          StartActivity(Me)
      End Sub


      #if java
      import anywheresoftware.b4a.objects.streams.*;
      public void _onCreate() {
          try {
          if (File.Exists(getFilesDir().toString(), "theme.txt"))
              _theme_value = Integer.parseInt(File.ReadString(getFilesDir().toString(), "theme.txt"));
          } catch (Exception e) {
              throw new RuntimeException(e);
          }
          if (_theme_value != 0)
              setTheme(_theme_value);
      }
      #end if

      Sub Activity_Resume

      End Sub

      Sub Activity_Pause (UserClosed As Boolean)

      End Sub

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