How to add a radio group to radio buttons inside of a table?

Question

I have multiple radio buttons which I want to layout using a table but also include them in a single radio group. I have the following xml layout:

<RadioGroup android:layout_width="fill_parent" 
      android:layout_height="wrap_content" 
      android:orientation="vertical"
      android:id="@+id/Group1">

    <TableLayout android:id="@+id/RadioButtons" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content">

        <TableRow>
            <RadioButton android:id="@+id/rad1" 
                android:text="RButton1" 
                android:layout_width="105px" 
                android:layout_height="wrap_content" 
                android:textSize="13px"></RadioButton>
            <RadioButton android:id="@+id/rad2" 
                android:text="RButton2" 
                android:layout_width="105px" 
                android:textSize="13px" 
                android:layout_height="wrap_content"></RadioButton>
            <RadioButton android:id="@+id/rad3" 
                android:text="RButton3" 
                android:layout_width="105px" 
                android:textSize="13px" 
                android:layout_height="wrap_content"></RadioButton>
        </TableRow>
      </TableLayout>
</RadioGroup>  

But unfortunately the radio buttons inside the table seem to ignore the fact that they're inside of the RadioGroup tags and because of this you can select more than one radio button at the time. I noticed that by removing the table and just having the radio buttons it works just fine. How can I overcome this? Would it be as simple as declaring the radio group inside of the table instead of outside? Thanks for any help.

Answer 1

Here is my RadioGroup/RadioButton extension (SoftRadioGroup/SoftRadioButton). RadioGroup is no more needed in the layout XML. You can group the RadioButtons with a property called group.

SoftRadioButton:

import java.util.HashMap;
import java.util.Random;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.RadioButton;

public class SoftRadioButton extends RadioButton {

    private static HashMap<String, SoftRadioGroup> GROUP_MAPPINGS = new HashMap<String, SoftRadioGroup>();
    private String mGroupName;

    public SoftRadioButton(Context context, AttributeSet attrs) {
        super(context, attrs);
        addToGroup(attrs);
    }

    public SoftRadioGroup getRadioGroup() {
        return GROUP_MAPPINGS.get(mGroupName);
    }

    private void addToGroup(AttributeSet attrs) {
        for (int i = 0; i < attrs.getAttributeCount(); i++) {
            if (attrs.getAttributeName(i).equals("group")) {
                String groupName = attrs.getAttributeValue(i);
                SoftRadioGroup group;
                if ((group = GROUP_MAPPINGS.get(groupName)) != null) {
                    // RadioGroup already exists
                    group.addView(this);
                    setOnClickListener(group);
                    mGroupName = groupName;

                } else {
                    // this is the first RadioButton in the RadioGroup
                    group = new SoftRadioGroup();
                    group.addView(this);
                    mGroupName = groupName;
                    setOnClickListener(group);

                    GROUP_MAPPINGS.put(groupName, group);
                }
                return;
            }
        }
        // group is not specified in the layout xml. Let's generate a random
        // RadioGroup
        SoftRadioGroup group = new SoftRadioGroup();
        group.addView(this);
        Random rn = new Random();
        String groupName;
        do {
            groupName = Integer.toString(rn.nextInt());
        } while (GROUP_MAPPINGS.containsKey(groupName));
        GROUP_MAPPINGS.put(groupName, group);
        mGroupName = groupName;
        setOnClickListener(group);

    }

}

SoftRadioGroup:

import java.util.ArrayList;

import android.view.View;
import android.view.View.OnClickListener;
import android.widget.RadioButton;

public class SoftRadioGroup implements OnClickListener {

    private ArrayList<RadioButton> buttons = new ArrayList<RadioButton>();

    public void addView(RadioButton button) {
        buttons.add(button);
    }

    @Override
    public void onClick(View v) {
        for (RadioButton button : buttons) {
            button.setChecked(false);
        }
        RadioButton button = (RadioButton) v;
        button.setChecked(true);
    }

    public RadioButton getCheckedRadioButton() {
        for (RadioButton button : buttons) {
            if (button.isSelected())
                return button;
        }
        return null;
    }

    public int getChildCount() {
        return buttons.size();
    }

    public RadioButton getChildAt(int i) {
        return buttons.get(i);
    }

    public void check(SoftRadioButton button) {
        if (buttons.contains(button)) {
            for (RadioButton b : buttons) {
                b.setChecked(false);
            }
        }
    }

}

Usage in XML layout embedded in a table (2 groups with 2 buttons per group):

<TableLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:stretchColumns="1" >

            <TableRow
                android:id="@+id/tableRow1"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content" >

                <Your.Package.SoftRadioButton
                    android:id="@+id/filterActivity_RadioButton_byDate"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:checked="true"
                    android:contentDescription="date"
                    android:text="@string/filterActivity_RadioButton_byDate"
                    fake:group="orderBy" />

                <Your.Package.SoftRadioButton
                    android:id="@+id/filterActivity_RadioButton_byPrice"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:contentDescription="price"
                    android:text="@string/filterActivity_RadioButton_byPrice"
                    fake:group="orderBy" />
            </TableRow>

            <TableRow
                android:id="@+id/tableRow2"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content" >

                <Your.Package.SoftRadioButton
                    android:id="@+id/filterActivity_RadioButton_asc"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:contentDescription="down"
                    android:text="@string/filterActivity_RadioButton_asc"
                    fake:group="direction" />

                <Your.Package.SoftRadioButton
                    android:id="@+id/filterActivity_RadioButton_desc"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:checked="true"
                    android:contentDescription="up"
                    android:text="@string/filterActivity_RadioButton_desc"
                    fake:group="direction" />
            </TableRow>
        </TableLayout>

Answer 2

rg1 = (RadioGroup)findViewById(R.id.radioGroup1);
        rg2 = (RadioGroup)findViewById(R.id.radioGroup2);
        rg1.setOnCheckedChangeListener(this);
        rg2.setOnCheckedChangeListener(this);
    }
    boolean rg1b = false;
    boolean rg2b = false;

    @Override
    public void onCheckedChanged(RadioGroup rgId, int radioButtonId) {
        switch (rgId.getId()) {
        case R.id.radioGroup1:
            rg1b=true;
            if(rg2b)
                rg2.clearCheck();
            break;

        case R.id.radioGroup2:
            rg1b=true;
            if(rg1b)
                rg1.clearCheck();
            break;
        }

Answer 3

Your RadioButton widgets must be immediate children of the RadioGroup for the group effect to work.