Android
android.widget
public class

android.widget.RadioGroup

java.lang.Object
android.view.View Drawable.Callback KeyEvent.Callback
android.view.ViewGroup ViewManager ViewParent
android.widget.LinearLayout
android.widget.RadioGroup

This class is used to create a multiple-exclusion scope for a set of radio buttons. Checking one radio button that belongs to a radio group unchecks any previously checked radio button within the same group.

Intially, all of the radio buttons are unchecked. While it is not possible to uncheck a particular radio button, the radio group can be cleared to remove the checked state.

The selection is identified by the unique id of the radio button as defined in the XML layout file.

XML Attributes

See RadioGroup Attributes, LinearLayout Attributes, ViewGroup Attributes, View Attributes

Also see LinearLayout.LayoutParams for layout attributes.

Nested Classes
RadioGroup.LayoutParams

This set of layout parameters defaults the width and the height of the children to WRAP_CONTENT when they are not specified in the XML file. 

RadioGroup.OnCheckedChangeListener

Interface definition for a callback to be invoked when the checked radio button changed in this group. 

See Also

Summary

XML Attributes inherited from class android.widget.LinearLayout
XML Attributes inherited from class android.view.ViewGroup
XML Attributes inherited from class android.view.View
Constants inherited from class android.widget.LinearLayout
Constants inherited from class android.view.ViewGroup
Constants inherited from class android.view.View
Fields inherited from class android.view.ViewGroup
Fields inherited from class android.view.View

Public Constructors

            RadioGroup(Context context)
            RadioGroup(Context context, AttributeSet attrs)

Public Methods

          void  check(int id)

Sets the selection to the radio button whose identifier is passed in parameter.

          void  clearCheck()

Clears the selection.

          RadioGroup.LayoutParams  generateLayoutParams(AttributeSet attrs)
Returns a new set of layout parameters based on the supplied attributes set.
          int  getCheckedRadioButtonId()

Returns the identifier of the selected radio button in this group.

          void  setOnCheckedChangeListener(RadioGroup.OnCheckedChangeListener listener)

Register a callback to be invoked when the checked radio button changes in this group.

          void  setOnHierarchyChangeListener(ViewGroup.OnHierarchyChangeListener listener)
Register a callback to be invoked when a child is added to or removed from this view.

Protected Methods

          boolean  checkLayoutParams(ViewGroup.LayoutParams p)
          LinearLayout.LayoutParams  generateDefaultLayoutParams()
Returns a set of layout parameters with a width of FILL_PARENT and a height of WRAP_CONTENT when the layout's orientation is VERTICAL.
          void  onFinishInflate()
Finalize inflating a view from XML.
Methods inherited from class android.widget.LinearLayout
Methods inherited from class android.view.ViewGroup
Methods inherited from class android.view.View
Methods inherited from class java.lang.Object
Methods inherited from interface android.graphics.drawable.Drawable.Callback
Methods inherited from interface android.view.KeyEvent.Callback
Methods inherited from interface android.view.ViewManager
Methods inherited from interface android.view.ViewParent

Details

Public Constructors

public RadioGroup(Context context)

public RadioGroup(Context context, AttributeSet attrs)

Public Methods

public void check(int id)

Sets the selection to the radio button whose identifier is passed in parameter. Using -1 as the selection identifier clears the selection; such an operation is equivalent to invoking clearCheck().

Parameters

id the unique id of the radio button to select in this group

public void clearCheck()

Clears the selection. When the selection is cleared, no radio button in this group is selected and getCheckedRadioButtonId() returns null.

public RadioGroup.LayoutParams generateLayoutParams(AttributeSet attrs)

Returns a new set of layout parameters based on the supplied attributes set.

Parameters

attrs the attributes to build the layout parameters from

public int getCheckedRadioButtonId()

Returns the identifier of the selected radio button in this group. Upon empty selection, the returned value is -1.

Returns

  • the unique id of the selected radio button in this group

public void setOnCheckedChangeListener(RadioGroup.OnCheckedChangeListener listener)

Register a callback to be invoked when the checked radio button changes in this group.

Parameters

listener the callback to call on checked state change

public void setOnHierarchyChangeListener(ViewGroup.OnHierarchyChangeListener listener)

Register a callback to be invoked when a child is added to or removed from this view.

Parameters

listener the callback to invoke on hierarchy change

Protected Methods

protected boolean checkLayoutParams(ViewGroup.LayoutParams p)

protected LinearLayout.LayoutParams generateDefaultLayoutParams()

Returns a set of layout parameters with a width of FILL_PARENT and a height of WRAP_CONTENT when the layout's orientation is VERTICAL. When the orientation is HORIZONTAL, the width is set to WRAP_CONTENT and the height to WRAP_CONTENT.

protected void onFinishInflate()

Finalize inflating a view from XML. This is called as the last phase of inflation, after all child views have been added.

Even if the subclass overrides onFinishInflate, they should always be sure to call the super method, so that we get called.

Copyright 2007 Google Inc. Build 0.9_r1-98467 - 14 Aug 2008 18:48