Android: Align many buttons nicely

Question

I have a RelativeLayout with 12 buttons, I want to align them nicely in the center of the screen and with equal distance to each others and equal left and right margins (like calculator buttons or telephone buttons). What I have done is in this XML file and the result in the pic, but it is still not perfect. Do you guys have any better solution for this?

 <RelativeLayout
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:id="@+id/tabview1">
    <TextView
        android:id="@+id/logo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:text="www.fasttest.me" 
        android:textColor="@android:color/white"/>

    <Button
        android:id="@+id/ql0"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="100dp"
        android:layout_marginLeft="10dp"
        android:text="b0" />
   <Button
        android:id="@+id/ql1"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="100dp"
        android:layout_marginLeft="80dp"
        android:text="b1" />
   <Button
        android:id="@+id/ql2"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="100dp"
        android:layout_marginLeft="150dp"
        android:text="b2" />
    <Button
        android:id="@+id/ql3"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="100dp"
       android:layout_marginLeft="220dp"
        android:text="b3" />
    <Button
        android:id="@+id/ql4"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="180dp"
        android:layout_marginLeft="10dp"
        android:text="b4" />
   <Button
        android:id="@+id/ql5"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="180dp"
        android:layout_marginLeft="80dp"
        android:text="b5" />
   <Button
        android:id="@+id/ql6"
         android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="180dp"
        android:layout_marginLeft="150dp"
        android:text="b6" />
    <Button
        android:id="@+id/ql7"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="180dp"
        android:layout_marginLeft="220dp"
        android:text="b7" />
   <Button
        android:id="@+id/ql8"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="260dp"
       android:layout_marginLeft="10dp"
        android:text="b8" />
   <Button
        android:id="@+id/ql9"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="260dp"
        android:layout_marginLeft="80dp"
        android:text="b9" />
   <Button
        android:id="@+id/ql10"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="260dp"
       android:layout_marginLeft="150dp"
        android:text="b10" />
    <Button
        android:id="@+id/ql11"
        android:layout_width="@dimen/qlbutton_width"
        android:layout_height="@dimen/qlbutton_height"
        android:layout_marginTop="260dp"
       android:layout_marginLeft="2dp"
        android:text="b11" />
   </RelativeLayout>

Answer 1

I finally get it done with a gridview of buttons. Here is the code:

public class MainActivity extends Activity {
    public String[] filenames ={"B1","B2","B3","B4","B5","B6"};        
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);           
        GridView gridView = (GridView) findViewById(R.id.gridview);
        gridView.setAdapter(new ButtonAdapter(this));  
        gridView.setOnItemClickListener(new OnItemClickListener(){
            public void onItemClick(AdapterView<?> parent, 
            View v, int position, long id){                
                Toast.makeText(getBaseContext(), 
                        "pic" + (position + 1) + " selected", 
                        Toast.LENGTH_SHORT).show();
            }
        });        
    }

    public class ButtonAdapter extends BaseAdapter {
        private Context context;    
        public ButtonAdapter(Context c){
            context = c;
        }
        public int getCount() {
            return filenames.length;
        }
        public Object getItem(int position) {
            return position;
        }     
        public long getItemId(int position) {
            return position;
        }
        public View getView(int position, View convertView, ViewGroup parent){
              Button btn;  
                 if (convertView == null) {   
                  btn = new Button(context);  
                  btn.setLayoutParams(new GridView.LayoutParams(100, 100));  
                  btn.setPadding(8, 8, 8, 8);  
                  btn.setFOcusable(false);
                  btn.setClickable(false);
                  }else {  
                  btn = (Button) convertView;  
                 }               
                 btn.setText(filenames[position]);    
                 btn.setTextColor(Color.WHITE);  
                 btn.setId(position);       
                 return btn; 
        }
    }    
}

Answer 2

You can use this custom GridLayout from Romain Guy. Specifiy the number of rows and columns. And the screen will be divided into equally sized cells.

Here is the link

Answer 3

I suggest you use buttons inside a GridView. Give each button the same weigh so it stretches itself:

<Button
    android:id="@+id/ql3"
    android:layout_height="@dime/button_height"
    android:layout_width="0dp"
    android:layout_weight="1"
    android:padding="@dimen/buttons_padding"
    android:text="b3" />