Android RadioGroup 换行, 支持多行多列

   经过反复试验，发现无论你怎么摆弄RadioGroup, 都无法实现多行多列的单选按钮组。 
1. 如果不结合其他布局，例如LinearLayout, 则只能实现单行多个按钮组，或者单列多个按钮组。 
2. 如果结合其他布局， 虽然可以实现多行多列的RadioButton布局，但是，如果不通过一些互斥算法，也无法实现按钮组的单选操作。 

所以，我对RadioGroup进行了改写. 

package com.example.ridiogroup;

import android.content.Context;  
import android.content.res.TypedArray;  
import android.util.AttributeSet;  
import android.view.MotionEvent;  
import android.view.View;  
import android.view.ViewGroup;  
import android.view.accessibility.AccessibilityEvent;  
import android.view.accessibility.AccessibilityNodeInfo;  
import android.widget.CompoundButton;  
import android.widget.LinearLayout;  
import android.widget.RadioButton;  
  
  
/** 
 * <p>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.</p> 
 * 
 * <p>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.</p> 
 * 
 * <p>The selection is identified by the unique id of the radio button as defined 
 * in the XML layout file.</p> 
 * 
 * <p><strong>XML Attributes</strong></p> 
 * <p>See {@link android.R.styleable#RadioGroup RadioGroup Attributes},  
 * {@link android.R.styleable#LinearLayout LinearLayout Attributes}, 
 * {@link android.R.styleable#ViewGroup ViewGroup Attributes}, 
 * {@link android.R.styleable#View View Attributes}</p> 
 * <p>Also see 
 * {@link android.widget.LinearLayout.LayoutParams LinearLayout.LayoutParams} 
 * for layout attributes.</p> 
 *  
 * @see RadioButton 
 * 
 */  
public class RadioGroup extends LinearLayout {  
    // holds the checked id; the selection is empty by default  
    private int mCheckedId = -1;  
    // tracks children radio buttons checked state  
    private CompoundButton.OnCheckedChangeListener mChildOnCheckedChangeListener;  
    // when true, mOnCheckedChangeListener discards events  
    private boolean mProtectFromCheckedChange = false;  
    private OnCheckedChangeListener mOnCheckedChangeListener;  
    private PassThroughHierarchyChangeListener mPassThroughListener;  
  
    /** 
     * {@inheritDoc} 
     */  
    public RadioGroup(Context context) {  
        super(context);  
        setOrientation(VERTICAL);  
        init();  
    }  
  
    /** 
     * {@inheritDoc} 
     */  
    public RadioGroup(Context context, AttributeSet attrs) {  
        super(context, attrs);  
        mCheckedId = View.NO_ID;  
  
        final int index = VERTICAL;  
        setOrientation(index);  
  
        init();  
    }  
  
    private void init() {  
        mChildOnCheckedChangeListener = new CheckedStateTracker();  
        mPassThroughListener = new PassThroughHierarchyChangeListener();  
        super.setOnHierarchyChangeListener(mPassThroughListener);  
    }  
  
    /** 
     * {@inheritDoc} 
     */  
    @Override  
    public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) {  
        // the user listener is delegated to our pass-through listener  
        mPassThroughListener.mOnHierarchyChangeListener = listener;  
    }  
  
    /** 
     * {@inheritDoc} 
     */  
    @Override  
    protected void onFinishInflate() {  
        super.onFinishInflate();  
  
        // checks the appropriate radio button as requested in the XML file  
        if (mCheckedId != -1) {  
            mProtectFromCheckedChange = true;  
            setCheckedStateForView(mCheckedId, true);  
            mProtectFromCheckedChange = false;  
            setCheckedId(mCheckedId);  
        }  
    }  
  
    @Override  
    public void addView(final View child, int index, ViewGroup.LayoutParams params) {  
        if (child instanceof RadioButton) {  
              
            ((RadioButton) child).setOnTouchListener(new OnTouchListener() {  
                  
                @Override  
                public boolean onTouch(View v, MotionEvent event) {  
                    ((RadioButton) child).setChecked(true);  
                    checkRadioButton((RadioButton) child);  
                    if(mOnCheckedChangeListener != null){  
                        mOnCheckedChangeListener.onCheckedChanged(RadioGroup.this, child.getId());  
                    }  
                    return true;  
                }  
            });  
              
        } else if(child instanceof LinearLayout){  
            int childCount = ((LinearLayout) child).getChildCount();  
            for(int i = 0; i < childCount; i++){  
                View view = ((LinearLayout) child).getChildAt(i);  
                if (view instanceof RadioButton) {  
                    final RadioButton button = (RadioButton) view;  
  
                      
                    ((RadioButton) button).setOnTouchListener(new OnTouchListener() {  
                          
                        @Override  
                        public boolean onTouch(View v, MotionEvent event) {  
                            ((RadioButton) button).setChecked(true);  
                            checkRadioButton((RadioButton) button);  
                            if(mOnCheckedChangeListener != null){  
                                mOnCheckedChangeListener.onCheckedChanged(RadioGroup.this, button.getId());  
                            }  
                            return true;  
                        }  
                    });  
                      
                }  
            }  
        }  
  
        super.addView(child, index, params);  
    }  
      
    private void checkRadioButton(RadioButton radioButton){  
        View child;  
        int radioCount = getChildCount();  
        for(int i = 0; i < radioCount; i++){  
            child = getChildAt(i);  
            if (child instanceof RadioButton) {  
                if(child == radioButton){  
                    // do nothing  
                } else {  
                    ((RadioButton) child).setChecked(false);  
                }  
            } else if(child instanceof LinearLayout){  
                int childCount = ((LinearLayout) child).getChildCount();  
                for(int j = 0; j < childCount; j++){  
                    View view = ((LinearLayout) child).getChildAt(j);  
                    if (view instanceof RadioButton) {  
                        final RadioButton button = (RadioButton) view;  
                        if(button == radioButton){  
                            // do nothing  
                        } else {  
                            ((RadioButton) button).setChecked(false);  
                        }  
                    }  
                }  
            }  
        }  
    }  
  
    /** 
     * <p>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 {@link #clearCheck()}.</p> 
     * 
     * @param id the unique id of the radio button to select in this group 
     * 
     * @see #getCheckedRadioButtonId() 
     * @see #clearCheck() 
     */  
    public void check(int id) {  
        // don't even bother  
        if (id != -1 && (id == mCheckedId)) {  
            return;  
        }  
  
        if (mCheckedId != -1) {  
            setCheckedStateForView(mCheckedId, false);  
        }  
  
        if (id != -1) {  
            setCheckedStateForView(id, true);  
        }  
  
        setCheckedId(id);  
    }  
  
    private void setCheckedId(int id) {  
        mCheckedId = id;  
    }  
  
    private void setCheckedStateForView(int viewId, boolean checked) {  
        View checkedView = findViewById(viewId);  
        if (checkedView != null && checkedView instanceof RadioButton) {  
            ((RadioButton) checkedView).setChecked(checked);  
        }  
    }  
  
    /** 
     * <p>Returns the identifier of the selected radio button in this group. 
     * Upon empty selection, the returned value is -1.</p> 
     * 
     * @return the unique id of the selected radio button in this group 
     * 
     * @see #check(int) 
     * @see #clearCheck() 
     * 
     * @attr ref android.R.styleable#RadioGroup_checkedButton 
     */  
    public int getCheckedRadioButtonId() {  
        return mCheckedId;  
    }  
  
    /** 
     * <p>Clears the selection. When the selection is cleared, no radio button 
     * in this group is selected and {@link #getCheckedRadioButtonId()} returns 
     * null.</p> 
     * 
     * @see #check(int) 
     * @see #getCheckedRadioButtonId() 
     */  
    public void clearCheck() {  
        check(-1);  
    }  
  
    /** 
     * <p>Register a callback to be invoked when the checked radio button 
     * changes in this group.</p> 
     * 
     * @param listener the callback to call on checked state change 
     */  
    public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {  
        mOnCheckedChangeListener = listener;  
    }  
  
    /** 
     * {@inheritDoc} 
     */  
    @Override  
    public LayoutParams generateLayoutParams(AttributeSet attrs) {  
        return new RadioGroup.LayoutParams(getContext(), attrs);  
    }  
  
    /** 
     * {@inheritDoc} 
     */  
    @Override  
    protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {  
        return p instanceof RadioGroup.LayoutParams;  
    }  
  
    @Override  
    protected LinearLayout.LayoutParams generateDefaultLayoutParams() {  
        return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);  
    }  
  
    @Override  
    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {  
        super.onInitializeAccessibilityEvent(event);  
        event.setClassName(RadioGroup.class.getName());  
    }  
  
    @Override  
    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {  
        super.onInitializeAccessibilityNodeInfo(info);  
        info.setClassName(RadioGroup.class.getName());  
    }  
  
    /** 
     * <p>This set of layout parameters defaults the width and the height of 
     * the children to {@link #WRAP_CONTENT} when they are not specified in the 
     * XML file. Otherwise, this class ussed the value read from the XML file.</p> 
     * 
     * <p>See 
     * {@link android.R.styleable#LinearLayout_Layout LinearLayout Attributes} 
     * for a list of all child view attributes that this class supports.</p> 
     * 
     */  
    public static class LayoutParams extends LinearLayout.LayoutParams {  
        /** 
         * {@inheritDoc} 
         */  
        public LayoutParams(Context c, AttributeSet attrs) {  
            super(c, attrs);  
        }  
  
        /** 
         * {@inheritDoc} 
         */  
        public LayoutParams(int w, int h) {  
            super(w, h);  
        }  
  
        /** 
         * {@inheritDoc} 
         */  
        public LayoutParams(int w, int h, float initWeight) {  
            super(w, h, initWeight);  
        }  
  
        /** 
         * {@inheritDoc} 
         */  
        public LayoutParams(ViewGroup.LayoutParams p) {  
            super(p);  
        }  
  
        /** 
         * {@inheritDoc} 
         */  
        public LayoutParams(MarginLayoutParams source) {  
            super(source);  
        }  
  
        /** 
         * <p>Fixes the child's width to 
         * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} and the child's 
         * height to  {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} 
         * when not specified in the XML file.</p> 
         * 
         * @param a the styled attributes set 
         * @param widthAttr the width attribute to fetch 
         * @param heightAttr the height attribute to fetch 
         */  
        @Override  
        protected void setBaseAttributes(TypedArray a,  
                int widthAttr, int heightAttr) {  
  
            if (a.hasValue(widthAttr)) {  
                width = a.getLayoutDimension(widthAttr, "layout_width");  
            } else {  
                width = WRAP_CONTENT;  
            }  
              
            if (a.hasValue(heightAttr)) {  
                height = a.getLayoutDimension(heightAttr, "layout_height");  
            } else {  
                height = WRAP_CONTENT;  
            }  
        }  
    }  
  
    /** 
     * <p>Interface definition for a callback to be invoked when the checked 
     * radio button changed in this group.</p> 
     */  
    public interface OnCheckedChangeListener {  
        /** 
         * <p>Called when the checked radio button has changed. When the 
         * selection is cleared, checkedId is -1.</p> 
         * 
         * @param group the group in which the checked radio button has changed 
         * @param checkedId the unique identifier of the newly checked radio button 
         */  
        public void onCheckedChanged(RadioGroup group, int checkedId);  
    }  
  
    private class CheckedStateTracker implements CompoundButton.OnCheckedChangeListener {  
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {  
            // prevents from infinite recursion  
            if (mProtectFromCheckedChange) {  
                return;  
            }  
  
            mProtectFromCheckedChange = true;  
            if (mCheckedId != -1) {  
                setCheckedStateForView(mCheckedId, false);  
            }  
            mProtectFromCheckedChange = false;  
  
            int id = buttonView.getId();  
            setCheckedId(id);  
        }  
    }  
  
    /** 
     * <p>A pass-through listener acts upon the events and dispatches them 
     * to another listener. This allows the table layout to set its own internal 
     * hierarchy change listener without preventing the user to setup his.</p> 
     */  
    private class PassThroughHierarchyChangeListener implements  
            ViewGroup.OnHierarchyChangeListener {  
        private ViewGroup.OnHierarchyChangeListener mOnHierarchyChangeListener;  
  
        /** 
         * {@inheritDoc} 
         */  
        public void onChildViewAdded(View parent, View child) {  
            if (parent == RadioGroup.this && child instanceof RadioButton) {  
                int id = child.getId();  
                // generates an id if it's missing  
                if (id == View.NO_ID) {  
                    id = child.hashCode();  
                    child.setId(id);  
                }  
                ((RadioButton) child).setOnCheckedChangeListener(  
                        mChildOnCheckedChangeListener);  
            }  
  
            if (mOnHierarchyChangeListener != null) {  
                mOnHierarchyChangeListener.onChildViewAdded(parent, child);  
            }  
        }  
  
        /** 
         * {@inheritDoc} 
         */  
        public void onChildViewRemoved(View parent, View child) {  
            if (parent == RadioGroup.this && child instanceof RadioButton) {  
                ((RadioButton) child).setOnCheckedChangeListener(null);  
            }  
  
            if (mOnHierarchyChangeListener != null) {  
                mOnHierarchyChangeListener.onChildViewRemoved(parent, child);  
            }  
        }  
    }  
} 

demo:http://download.csdn.net/detail/u012350993/9061727

摘自：http://developer.51cto.com/art/201001/180261.html