Module com.googlecode.lanterna
Package com.googlecode.lanterna.gui2

Interface TextGUI

  • All Known Subinterfaces:
    WindowBasedTextGUI
    All Known Implementing Classes:
    AbstractTextGUI, MultiWindowTextGUI
    public interface TextGUI
    This is the base interface for advanced text GUIs supported in Lanterna. You may want to use this in combination with a TextGUIThread, that can be created/retrieved by using getGUIThread().

    • Method Detail

      • getTheme

        Theme getTheme()
        Returns the theme currently assigned to this TextGUI
        Returns:
        Currently active Theme

      • setTheme

        void setTheme​(Theme theme)
        Sets the global theme to be used by this TextGUI. This value will be set on every TextGUIGraphics object created for drawing the GUI, but individual components can override this if they want. If you don't call this method you should assume that a default theme is assigned by the library.
        Parameters:
        theme - Theme to use as the default theme for this TextGUI

      • processInput

        boolean processInput()
              throws java.io.IOException
        Drains the input queue and passes the key strokes to the GUI system for processing. For window-based system, it will send each key stroke to the active window for processing. If the input read gives an EOF, it will throw EOFException and this is normally the signal to shut down the GUI (any command coming in before the EOF will be processed as usual before this).
        Returns:
        true if at least one key stroke was read and processed, false if there was nothing on the input queue (only for non-blocking IO)
        Throws:
        java.io.IOException - In case there was an underlying I/O error
        java.io.EOFException - In the input stream received an EOF marker

      • updateScreen

        void updateScreen()
           throws java.io.IOException
        Updates the screen, to make any changes visible to the user.
        Throws:
        java.io.IOException - In case there was an underlying I/O error

      • isPendingUpdate

        boolean isPendingUpdate()
        This method can be used to determine if any component has requested a redraw. If this method returns true, you may want to call updateScreen().
        Returns:
        true if this TextGUI has a change and is waiting for someone to call updateScreen()

      • setVirtualScreenEnabled

        void setVirtualScreenEnabled​(boolean virtualScreenEnabled)
        This method controls whether or not the virtual screen should be used. This is what enabled you to make your UI larger than what fits the terminal, as it will expand the virtual area and put in scrollbars. If set to false, the virtual screen will be bypassed and any content outside of the screen will be cropped. This property is true by default.
        Parameters:
        virtualScreenEnabled - If true, then virtual screen will be used, otherwise it is bypassed

      • getGUIThread

        TextGUIThread getGUIThread()
        The first time this method is called, it will create a new TextGUIThread object that you can use to automatically manage this TextGUI instead of manually calling processInput() and updateScreen(). After the initial call, it will return the same object as it was originally returning.
        Returns:
        A TextGUIThread implementation that can be used to asynchronously manage the GUI

      • getFocusedInteractable

        Interactable getFocusedInteractable()
        Returns the interactable component currently in focus
        Returns:
        Component that is currently in input focus

      • addListener

        void addListener​(TextGUI.Listener listener)
        Adds a listener to this TextGUI to fire events on.
        Parameters:
        listener - Listener to add

      • removeListener

        void removeListener​(TextGUI.Listener listener)
        Removes a listener from this TextGUI so that it will no longer receive events
        Parameters:
        listener - Listener to remove