Help Center
Local Navigation
- Creating user interfaces
- Screens
- UI components
- Add a UI component to a screen
- Create a dialog box
- Creat a bitmap
- Create a button
- Create a list
- Create an alphanumeric drop-down list
- Create a text list that can be filtered
- Create a check box
- Create a radio button
- Create a date field
- Create a text field
- Create a read-only text field that allows formatting
- Create an editable text field that has no formatting and accepts filters
- Create an editable text field that allows special characters
- Create a password field
- Create a text field for AutoText
- Create a progress bar field
- Create a text label
- Create a list from which users can select multiple items
- Create a field to display a parent and child relationship between items
- Add a UI component to a screen
- Create a custom field
- Create a menu item
- Adding menu items to a BlackBerry device application
- Register a menu item
- Arrange UI components
- UI events
- Spell check
- Accessibility
- Notifying an assistive technology application when the UI changes
- UI changes that trigger a notification to an assistive technology application
- UI component states and properties
- Provide an assistive technology application with information about a UI change
- Provide an assistive technology application with information about text changes
- Provide an assistive technology application with access to information from a table
- Provide an assistive technology application with access to numeric values
- Allow an assistive technology application to receive notification of field changes
- Storing data
- Creating connections
- Network gateways
- Connections
- Wi-Fi connections
- Wireless access families
- Retrieve the wireless access families that a BlackBerry device supports
- Determine if a BlackBerry device supports multiple wireless access families
- Determine the wireless access family transceivers that are turned on
- Turn on the transceiver for a wireless access family
- Turn off the transceiver for a wireless access family
- Check if the Wi-Fi transceiver is turned on
- Check if the Wi-Fi transceiver is connected to a wireless access point
- Retrieve the status of the wireless access point or the active Wi-Fi profile
- Open a Wi-Fi socket connection
- Open a Wi-Fi HTTP connection
- Open a Wi-Fi HTTPS connection
- Managing applications
- Using custom messages and folders in the message list
- Creating a module for background processes
- Creating a module for the UI
- Create the module for background processes
- Start the module for background processes or the module for the UI
- Create an icon for a custom message
- Create a custom folder in the message list
- Send a notification when a custom folder changes
- Create an indicator for the number of messages in a custom folder
- Hide an indicator for a custom folder
- Remove an indicator for a custom folder
- Applications for push content
- Localizing BlackBerry device applications
- Controlling access to APIs and application data
- Check if a code signature is required
- Java APIs with controlled access
- Register to use controlled APIs
- Restrictions on code signatures
- Request a code signature
- Register a signature key using a proxy server
- Sign an application using a proxy server
- View the signature status for an application
- Using keys to protect APIs and data
- Protect APIs using code signing keys
- Protect runtime store data using code signing keys
- Protect persistent data using code signing keys
- Testing a BlackBerry device application
- Packaging and distributing a BlackBerry Java Application
- Preverify a BlackBerry device application
- Application distribution over the wireless network
- Wireless pull (user-initiated)
- Wireless push (server-initiated)
- Distributing BlackBerry Java Applications over the wireless network
- Distributing BlackBerry device applications with the BlackBerry Desktop Software
- Application distribution through a computer connection
- Distributing an application from a computer
- Create an application loader file
- Install a BlackBerry device application on a specific device
- Specifing supported versions of the BlackBerry Device Software
- Glossary
- Provide feedback
- Legal notice
BlackBerry Manuals & Help
>
Documentation for Developers
>
Java Development Guides and API Reference
>
Development Guide - BlackBerry Java Development Environment - 4.6.1
Manage a drawing area
The Graphics object represents the entire drawing surface that is available to the BlackBerry® device application. To limit this area, divide it into XYRect objects. Each XYPoint represents a point on the screen, which is composed of an X co-ordinate and a Y co-ordinate.
- Import the following classes:
- Create an instance of an XYPoint object and an XYRect object.
XYPoint bottomRight = new XYPoint(50, 50); XYRect rectangle = new XYRect(topLeft, bottomRight); XYPoint topLeft = new XYPoint(10, 10);
- Invoke Graphics.pushContext() to make drawing calls that specify that the region origin should not adjust the drawing offset.
In the following code sample, we create two XYPoint objects to represent the top left and bottom right points of a rectangle. We then create a rectangular clipping region by creating an XYRect object using the XYPoint objects. We invoke Graphics.pushContext()
to push the rectangular clipping region
to the context stack. We invoke Graphics.drawRect()
to draw a rectangle and invoke Graphics.fillRect() to fill a rectangle. We invoke Graphics.popContext()
to pop the current context off of the context stack.
XYPoint bottomRight = new XYPoint(50, 50); XYPoint topLeft = new XYPoint(10, 10); XYRect rectangle = new XYRect(topLeft, bottomRight); graphics.pushContext(rectangle, 0, 0); graphics.fillRect(10, 10, 30, 30); graphics.drawRect(15, 15, 30, 30); graphics.popContext(); graphics.drawRect(15, 15, 30, 30); graphics.pushContext(rectangle, 0, 0); graphics.fillRect(10, 10, 30, 30); graphics.drawRect(15, 15, 30, 30); graphics.popContext(); graphics.drawRect(15, 15, 30, 30);
- Invoke pushRegion()
and specify that the region origin should adjust the drawing offset.
In the following code sample, we invoke Graphics.drawRect()
to draw a rectangle and invoke Graphics.fillRect() to fill a rectangle. We invoke Graphics.popContext()
to pop the current context off of the context stack.
graphics.pushRegion(rectangle); graphics.fillRect(10, 10, 30, 30); graphics.drawRect(15, 15, 30, 30); graphics.popContext();
- Invert a specified XYRect object.
- Specify the portion of the Graphics object to push onto the stack.
- After you invoke pushContext() (or pushRegion()), provide the portion of the Graphics object to invert.
graphics.pushContext(rectangle); graphics.invert(rectangle); graphics.popContext();
- Invoke translate(). The XYRect is translated from its origin of (1, 1) to an origin of (20, 20). After translation, the bottom portion of the XYRect object extends past the bounds of the graphics context and clips it.
XYRect rectangle = new XYRect(1, 1, 100, 100); XYPoint newLocation = new XYPoint(20, 20); rectangle.translate(newLocation);
Parent topic: Screens