TextBoxWithSuggText.java 文件源码

/**
 * Allows to initialize the text box by setting up its listeners and styles.
 */
private void initialize() {
    //Set the base values and styles
    super.setStyleName( CommonResourcesContainer.GWT_TEXT_BOX_STYLE );
    this.addStyleName( CommonResourcesContainer.USER_DIALOG_SUGG_TEXT_BOX_STYLE );
    this.setText( helperText );
    //On gaining the focus
    addFocusHandler(new FocusHandler(){
        public void onFocus(FocusEvent event) {
            //If the focus is obtained and the text box value is set to empty if
            //the user text was not set, i.e. he have the helper message there
            if( TextBoxWithSuggText.super.getText().trim().equals( helperText ) ){
                TextBoxWithSuggText.super.setText( "" );
            }
            //Remove the suggestion style making the text be in another color
            removeStyleName( CommonResourcesContainer.USER_DIALOG_SUGG_TEXT_BOX_STYLE );
        }
    });
    //On loosing the focus
    addBlurHandler(new BlurHandler(){
        public void onBlur(BlurEvent e) {
            //If the text box looses the focus and the text is not set
            //then we set the helper text and the corresponding style 
            if( TextBoxWithSuggText.super.getText().trim().isEmpty() ){
                TextBoxWithSuggText.this.setText( null );
            }
        }
    });
}