title: Flutter - how to remove default padding (48 px as per doc) from widgets (IconButton, CheckBox, FlatButton)
body: <p>I am facing a problem with the default padding of the widgets (IconButton, CheckBox, FlatButton). I have searched a lot for this concern but with no success.</p>
  <p><a href="https://i.stack.imgur.com/AhOTU.png" rel="noreferrer"><img src="https://i.stack.imgur.com/AhOTU.png" alt="enter image description here" /></a></p>
  <p>In the above image, the outer blue rect is the actual size of these widgets and I have to remove that space.</p>
  <pre><code>Checkbox(
            onChanged: (value) {
              setState(() {
                _rememberMeFlag = !_rememberMeFlag;
              });
            },
            value: _rememberMeFlag,
            activeColor: const Color(0xff00bbff),
            materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
          )
  </code></pre>
  <p>and below is the widget code for hide/show widget icon:</p>
  <pre><code>new Container(
            child: TextFormField(
              decoration: InputDecoration(
                labelText: &quot;Password&quot;,
                suffixIcon: Padding(
                  padding: EdgeInsetsDirectional.zero,
                  child: GestureDetector(
                    child: Icon(
                      hidePassword ? Icons.visibility : Icons.visibility_off,
                      size: 20.0,
                      color: Colors.black,
                    ),
                  ),
                ),
                contentPadding: const EdgeInsets.only(
                    left: 0.0, top: 6.0, bottom: 6.0, right: 0.0),
              ),
              obscureText: !hidePassword,
              maxLength: 20,
            ),
          )
  </code></pre>
  <p>I have tried to set the container size too but no luck. Also tried the padding properties of the widgets but with no success.</p>
  <p>Is there any way to remove this extra spacing from these widgets?</p>