title: Extjs4 Upload file with just one button
body: <p>I want to upload a file with just one button "Upload button", which on clicked, opens file chooser, and if file selected, it must upload it.</p>
  
  <p>The view should not show <code>input[type=file]</code> or any other labels, but just one button.</p>
  
  <p>I know it is easy with jQuery or just javascript, but since I am relatively new to Extjs, I writing this here looking for your help.</p>
  
  <p>Below is the sample file uploader from documentation. How can I customize it to fit my needs:</p>
  
  <pre><code>Ext.create('Ext.form.Panel', {
  title: 'Upload a Photo',
  width: 400,
  bodyPadding: 10,
  frame: true,
  renderTo: Ext.getBody(),
  items: [{
      xtype: 'filefield',
      name: 'photo',
      fieldLabel: 'Photo',
      labelWidth: 50,
      msgTarget: 'side',
      allowBlank: false,
      anchor: '100%',
      buttonText: 'Select Photo...'
  }],
  
  buttons: [{
      text: 'Upload',
      handler: function() {
          var form = this.up('form').getForm();
          if(form.isValid()){
              form.submit({
                  url: 'photo-upload.php',
                  waitMsg: 'Uploading your photo...',
                  success: function(fp, o) {
                      Ext.Msg.alert('Success', 'Your photo "' + o.result.file + '" has been uploaded.');
                  }
              });
          }
      }
  }]
  });
  </code></pre>