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- 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
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Java Development Guides and API Reference
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Development Guide - BlackBerry Java Development Environment - 4.6.1
Create a field to display a parent and child relationship between items
- Import the following classes:
- Import the net.rim.device.api.ui.component.TreeFieldCallback interface.
- Implement the TreeFieldCallback interface.
- Invoke TreeField.setExpanded() on the TreeField object
to specify whether a folder is collapsible. In the following code sample, we create a TreeField object and multiple child nodes to the TreeField object. We then invoke TreeField.setExpanded()
using node4 as a parameter to collapse the folder.
String fieldOne = new String("Main folder"); ... TreeCallback myCallback = new TreeCallback(); TreeField myTree = new TreeField(myCallback, Field.FOCUSABLE); int node1 = myTree.addChildNode(0, fieldOne); int node2 = myTree.addChildNode(0, fieldTwo); int node3 = myTree.addChildNode(node2, fieldThree); int node4 = myTree.addChildNode(node3, fieldFour); ... int node10 = myTree.addChildNode(node1, fieldTen); myTree.setExpanded(node4, false); ... mainScreen.add(myTree); - To repaint a TreeField when a node changes, create a class that implements the TreeFieldCallback interface and implement the TreeFieldCallback.drawTreeItem method. In the following code sample, the TreeFieldCallback.drawTreeItem method
uses the cookie for a tree node to draw a String in the location of a node. The TreeFieldCallback.drawTreeItem method
invokes Graphics.drawText() to draw the String.
private class TreeCallback implements TreeFieldCallback { public void drawTreeItem(TreeField _tree, Graphics g, int node, int y, int width, int indent) { String text = (String)_tree.getCookie(node); g.drawText(text, indent, y); } }
Parent topic: UI components