Different types of Selection Screens in abap

Different Types of Selection Screens

What is:
1. at selection-screen on field
2. at selection-screen output
3. at selection-screen block
4. at selection-screen on value-request
5. at selection-screen on help-request and their difference?

For knowing Selection-screens:

First you must have right understanding of Events.
– Events are introduced by Event Keyword.  They end when again next processs begins.

Selection-screens are special screen defined in ABAP.
– This ABAP at run time only controls the flow logic of Selection-screens.  The PBO and PAI triggers the num of. selection-screens.

The basic form of the selection screen events is the AT SELECTION-SCREEN event. This event occurs after the runtime environment has passed all input data from the selection screen to the ABAP program. The other selection screen events allow programmers to modify the selection screen before it is sent and specifically check user input.

At Selection-screen OUTPUT is trigerred in PBO of selection-screen.
– This allows you to modify the Selection-screen, before it is displayed.

At Selection-screen On Field is triggered in PAI of selection-screens.
– The input fields can b checked,in the corresponding event block. If an error message occurs within this event block, the corresponding field is made ready for input again on the selection screen.

At Selection-screen On Block is trigerred in PAI event.
– You define a block  by enclosing the declarations of the elements in the block between the statements SELECTION-SCREEN BEGIN OF BLOCK block – END OF BLOCK block. You can use this event block to check the consistency of the input fields in the block.

At Selection-screen On value request.
– This event is trigerred for F4 help.

At Selection-screen On help request .
– This event is triggered when the user clicks F1 for help on fileds.

For all entries in abap

Folks,

When should we go for inner joins and when for all entries?? basic explanation is given below..

say if u want to display material and its text. u can use this concept.

 

~from the master table i’m selecting the materials based on the input s_matnr.

~then for the materials selected above , i have to get their corresponding description.

ie:

select matnr from mara into table i_matnr

where matnr in s_matnr.

 

if sy-subrc = 0.

select matnr maktx

from makt into table i_makt

for all entries in i_matnr

where matnr = i_mara-matnr.

endif.

This is similar to INNER JOIN concept. get the common data from 2 tables based on the input. Sometimes Join will give poor performance , n there u can use FOR ALL ENTRIES.

 

Joins have the advantage of linking two or more tables based on few of the conditions.However, there are a few disadvantages with same.

1) Duplicates are removed from the resulting set.Hence proper care has to be taken for the unique fields and keys that are used to determine the result.

2)If the resulting table is going to be very large, performace can be well affected.


   It is in this scenario , we use “for all entries“.The strategy would be to obtain the results for first table and based on the entries of first table, second table is filled and so on.But if the table on which the For All Entries IN clause is based is empty, all rows are selected into the destination table. Hence it is advisable to check before-hand that the first table is not empty. 

For more: http://help.sap.com/abapdocu_702/en/abenwhere_logexp_itab.htm

HTML5 New API’s and Changed API’s

APIs

HTML5 has introduced many new APIs and have extended, changed or obsoleted some existing APIs.

5.1 New APIs

HTML5 introduces a number of APIs that help in creating Web applications. These can be used together with the new elements introduced for applications:

  • Media elements (video and audio) have APIs for controlling playback, syncronising multiple media elements, and timed text tracks (e.g. subtitles).
  • An API for form constraint validation (e.g. the setCustomValidity() method).
  • An API for commands that the user can invoke (used together with the command element among others).
  • An API that enables offline Web applications, with an application cache.
  • An API that allows a Web application to register itself for certain protocols or media types, using registerProtocolHandler() and registerContentHandler() .
  • Editing API in combination with a new global contenteditable attribute.
  • Drag & drop API in combination with a draggable attribute.
  • An API that exposes the components of the document’s URL and allows scripts to navigate, redirect and reload (the Location interface).
  • An API that exposes the session history and allows scripts to update the document’s URL without actually navigating, so that applications don’t need to abuse the fragment component for “Ajax-style” navigation (the History interface).
  • An API for base64 conversion (atob() and btoa() methods).
  • An API to schedule timer-based callbacks (setTimeout() and setInterval()).
  • An API to prompt the user (alert()confirm()prompt()showModalDialog()).
  • An API for printing the document (print()).
  • An API for handling search providers (AddSearchProvider() and IsSearchProviderInstalled()).
  • The Window object has been defined.

WHATWG HTML has further APIs that are not in HTML5 but are separate specifications at the W3C:

5.2 Changed APIs

The following features from DOM Level 2 HTML are changed in various ways:

HTML5 Changed attributes

Changed Attributes

Several attributes have changed in various ways.

  • The accept attribute on input now allows the values audio/*video/* and image/*.
  • The accesskey global attribute now allows multiple characters to be specified, which the user agent can choose from.
  • The action attribute on form is no longer allowed to have an empty URL.
  • In WHATWG HTML, the method attribute has a new keyword dialog, intended to close a dialog element.
  • The border attribute on table only allows the values “1” and the empty string. In WHATWG HTML, the border attribute is obsolete.
  • The colspan attribute on td and th now has to be greater than zero.
  • The coords attribute on area no longer allows a percentage value of the radius when the element is in the circle state.
  • The data attribute on object is no longer said to be relative to the codebase attribute.
  • The defer attribute on script now explicitly makes the script execute when the page has finished parsing.
  • The dir global attribute now allows the value auto.
  • The enctype attribute on form now supports the value text/plain.
  • The width and height attributes on imgiframe and object are no longer allowed to contain percentages. They are also not allowed to be used to stretch the image to a different aspect ratio than its intrinsic aspect ratio.
  • The href attribute on link is no longer allowed to have an empty URL.
  • The href attribute on base is now allowed to contain a relative URL.
  • All attributes that take URLs, e.g. href on the a element, now support IRIs if the document’s encoding is UTF-8 or UTF-16.
  • The http-equiv attribute on meta is no longer said to be used by HTTP servers to create HTTP headers in the HTTP response. Instead, it is said to be a pragma directive to be used by the user agent.
  • The id global attribute is now allowed to have any value, as long as it is unique, is not the empty string, and does not contain space characters.
  • The lang global attribute takes the empty string in addition to a valid language identifier, just like xml:lang does in XML.
  • The media attribute on link now accepts a media query and defaults to “all”.
  • The event handler attributes (e.g. onclick) now always use JavaScript as the scripting language.
  • The value attribute of the li element is no longer deprecated as it is not presentational. The same goes for the start and type attributes of the ol element.
  • The style global attribute now always uses CSS as the styling language.
  • The tabindex global attribute now allows negative values which indicate that the element can receive focus but cannot be tabbed to.
  • The target attribute of the a and area elements is no longer deprecated, as it is useful in Web applications, e.g. in conjunction with iframe.
  • The type attribute on script and style is no longer required if the scripting language is JavaScript and the styling language is CSS, respectively.
  • The usemap attribute on img no longer takes a URL, but instead takes a valid hash-name reference to a map element.

The following attributes are allowed but authors are discouraged from using them and instead strongly encouraged to use an alternative solution:

  • The border attribute on img. It is required to have the value “0” when present. Authors can use CSS instead.
  • The language attribute on script. It is required to have the value “JavaScript” (case-insensitive) when present and cannot conflict with the type attribute. Authors can simply omit it as it has no useful function.
  • The name attribute on a. Authors can use the id attribute instead.

HTML5 Changed Elements

Changed Elements

These elements have slightly modified meanings in HTML5 to better reflect how they are used on the Web or to make them more useful:

  • The address element is now scoped by the nearest ancestor article or body element.
  • The b element now represents a span of text to which attention is being drawn for utilitarian purposes without conveying any extra importance and with no implication of an alternate voice or mood, such as key words in a document abstract, product names in a review, actionable words in interactive text-driven software, or an article lede.
  • The cite element now solely represents the title of a work (e.g. a book, a paper, an essay, a poem, a score, a song, a script, a film, a TV show, a game, a sculpture, a painting, a theatre production, a play, an opera, a musical, an exhibition, a legal case report, etc). Specifically the example in HTML4 where it is used to mark up the name of a person is no longer considered conforming.
  • The dl element now represents an association list of name-value groups, and is no longer said to be appropriate for dialogue.
  • The hr element now represents a paragraph-level thematic break.
  • The i element now represents a span of text in an alternate voice or mood, or otherwise offset from the normal prose in a manner indicating a different quality of text, such as a taxonomic designation, a technical term, an idiomatic phrase from another language, a thought, or a ship name in Western texts.
  • For the label element the browser should no longer move focus from the label to the control unless such behavior is standard for the underlying platform user interface.
  • The menu element is redefined to be useful for toolbars and context menus.
  • The noscript element is no longer said to be rendered when the user agent doesn’t support a scripting language invoked by a script element earlier in the document.
  • The s element now represents contents that are no longer accurate or no longer relevant.
  • The script element can now be used for scripts or for custom data blocks.
  • The small element now represents side comments such as small print.
  • The strong element now represents importance rather than strong emphasis.
  • The u element now represents a span of text with an unarticulated, though explicitly rendered, non-textual annotation, such as labeling the text as being a proper name in Chinese text (a Chinese proper name mark), or labeling the text as being misspelt.

HTML5 New Attributes

New Attributes

Several attributes have been introduced to various elements that were already part of HTML4:

  • The a and area elements now have a media attribute for consistency with the link element. WHATWG HTML also has the download and ping attributes.
  • The area element, for consistency with the a and link elements, now also has the hreflangtype and rel attributes.
  • The base element can now have a target attribute as well, mainly for consistency with the a element. (This is already widely supported.)
  • The meta element has a charset attribute now as this was already widely supported and provides a nice way to specify the character encoding for the document.
  • A new autofocus attribute can be specified on the input (except when the type attribute is hidden), selecttextarea and button elements. It provides a declarative way to focus a form control during page load. Using this feature should enhance the user experience compared to focusing the element with script as the user can turn it off if the user does not like it, for instance.
  • A new placeholder attribute can be specified on the input and textarea elements. It represents a hint intended to aid the user with data entry.
    <input type=email placeholder="a@b.com">
  • The new form attribute for inputoutputselecttextareabuttonlabelobject and fieldset elements allows for controls to be associated with a form. These elements can now be placed anywhere on a page, not just as descendants of the form element, and still be associated with a form.
    <table>
     <tr>
      <th>Key
      <th>Value
      <th>Action
     <tr>
      <td><form id=1><input name=1-key></form>
      <td><input form=1 name=1-value>
      <td><button form=1 name=1-action value=save>✓</button>
          <button form=1 name=1-action value=delete>✗</button>
     ...
    </table>
  • The new required attribute applies to input (except when the type attribute is hiddenimage or some button type such as submit), select and textarea. It indicates that the user has to fill in a value in order to submit the form. For select, the first option element has to be a placeholder with an empty value.
    <label>Color: <select name=color required>
     <option value="">Choose one
     <option>Red
     <option>Green
     <option>Blue
    </select></label>
  • The fieldset element now allows the disabled attribute which disables all descendant controls (excluding those that are descendants of the legend element) when specified, and the name attribute which can be used for script access.
  • The input element has several new attributes to specify constraints: autocompleteminmaxmultiplepattern and step. As mentioned before it also has a newlist attribute which can be used together with the datalist element. It also now has the width and height attributes to specify the dimensions of the image when using type=image.
  • The input and textarea elements have a new attribute named dirname that causes the directionality of the control as set by the user to be submitted as well.
  • The textarea element also has two new attributes, maxlength and wrap which control max input length and submitted line wrapping behavior, respectively.
  • The form element has a novalidate attribute that can be used to disable form validation submission (i.e. the form can always be submitted).
  • The input and button elements have formactionformenctypeformmethodformnovalidate, and formtarget as new attributes. If present, they override the action,enctypemethodnovalidate, and target attributes on the form element.
  • In WHATWG HTML, the input and textarea have an inputmode attribute.
  • The menu element has two new attributes: type and label. They allow the element to transform into a menu as found in typical user interfaces as well as providing for context menus in conjunction with the global contextmenu attribute.
  • The style element has a new scoped attribute which can be used to enable scoped style sheets. Style rules within such a style element only apply to the local tree.
  • The script element has a new attribute called async that influences script loading and execution.
  • The html element has a new attribute called manifest that points to an application cache manifest used in conjunction with the API for offline Web applications.
  • The link element has a new attribute called sizes. It can be used in conjunction with the icon relationship (set through the rel attribute; can be used for e.g. favicons) to indicate the size of the referenced icon. Thus allowing for icons of distinct dimensions.
  • The ol element has a new attribute called reversed. When present, it indicates that the list order is descending.
  • The iframe element has three new attributes called sandboxseamless, and srcdoc which allow for sandboxing content, e.g. blog comments.
  • The object element has a new attribute called typemustmatch which allows safer embedding of external resources.
  • The img element has a new attribute called crossorigin to use CORS in the fetch and if it is successful, allows the image data to be read with the canvas API. In WHATWG HTML, there is also a new attribute called srcset to support multiple images for different resolutions and different images for different viewport sizes.

Several attributes from HTML4 now apply to all elements. These are called global attributes: accesskeyclassdiridlangstyletabindex and title. Additionally, XHTML 1.0 only allowed xml:space on some elements, which is now allowed on all elements in XHTML documents.

There are also several new global attributes:

  • The contenteditable attribute indicates that the element is an editable area. The user can change the contents of the element and manipulate the markup.
  • The contextmenu attribute can be used to point to a context menu provided by the author.
  • The data-* collection of author-defined attributes. Authors can define any attribute they want as long as they prefix it with data- to avoid clashes with future versions of HTML. These are intended to be used to store custom data to be consumed by the Web page or application itself. They are not intended for data to be consumed by other parties (e.g. user agents).
  • The draggable and dropzone attributes can be used together with the new drag & drop API.
  • The hidden attribute indicates that an element is not yet, or is no longer, relevant.
  • WHATWG HTML has the inert attribute, intended to make dialog elements modal.
  • The role and aria-* collection attributes which can be used to instruct assistive technology.
  • The spellcheck attribute allows for hinting whether content can be checked for spelling or not.
  • The translate attribute gives a hint to translators whether the content should be translated.

HTML5 also makes all event handler attributes from HTML4, which take the form onevent, global attributes and adds several new event handler attributes for new events it defines. For instance, the onplay event handler attribute for the play event which is used by the API for the media elements (video and audio).

Difference between HTML4 & HTML5

Hey guys,

Lets see briefly what is the difference between HTML4 & HTML5 today…

Before get into deep of html5 lets look into some basics.. 😉

Do u know what is doctype and why its used??

The HTML syntax of HTML5 requires a doctype to be specified to ensure that the browser renders the page in standards mode. The doctype has no other purpose.

In order to deal both with content written according to Web standards and with content written according to legacy practices that were prevalent in the late 1990s, today’s Web browsers implement various engine modes.

Names of Browser Engines

Browser Engine ECMAScript Engine
Firefox, Mozilla Gecko SpiderMonkey
Internet Explorer 4…7 Trident jscript
Mac IE 5 Tasman jscript
Opera 7…9.2 Presto linear_b
Opera 9.5 Presto Core 2 futhark
Konqueror KHTML KJS
Safari WebKit JavaScriptCore

Chrome – WebKit, V8 JavaScript engine

  • The script engine of Mac IE 5 is a port of the engine that is used in Windows IE although the layout engines are different.
  • WebKit and JavaScriptCore are forks of KHTML and KJS.

For more..Clickhere

What is HTML5?

HTML5 is the latest version of HTML and XHTML. It comes up with a number of features like drag and drop, multimedia, video playback, APIs, form control etc.

What are the benefits of HTML5?

  • HTML5 brings in new elements to structure the web pages as compared to HTML4 which uses common structures such as: – header, columns etc.
  • These new elements are: header, nav, section, article, aside,  footer etc.

New Elements

The following elements have been introduced for better structure:

  • section represents a generic document or application section. It can be used together with the h1h2h3h4h5, and h6 elements to indicate the document structure.
  • article represents an independent piece of content of a document, such as a blog entry or newspaper article.
  • aside represents a piece of content that is only slightly related to the rest of the page.
  • hgroup represents the header of a section.
  • header represents a group of introductory or navigational aids.
  • footer represents a footer for a section and can contain information about the author, copyright information, etc.
  • nav represents a section of the document intended for navigation.
  • figure represents a piece of self-contained flow content, typically referenced as a single unit from the main flow of the document.
    <figure>
     <video src="example.webm" controls></video>
     <figcaption>Example</figcaption>
    </figure>

    figcaption can be used as caption (it is optional).

Then there are several other new elements:

  • video and audio for multimedia content. Both provide an API so application authors can script their own user interface, but there is also a way to trigger a user interface provided by the user agent. source elements are used together with these elements if there are multiple streams available of different types.
  • track provides text tracks for the video element.
  • embed is used for plugin content.
  • mark represents a run of text in one document marked or highlighted for reference purposes, due to its relevance in another context.
  • progress represents a completion of a task, such as downloading or when performing a series of expensive operations.
  • meter represents a measurement, such as disk usage.
  • time represents a date and/or time.
  • WHATWG HTML has data which allows content to be annotated with a machine-readable value.
  • WHATWG HTML has dialog for showing a dialog.
  • rubyrt, and rp allow for marking up ruby annotations.
  • bdi represents a span of text that is to be isolated from its surroundings for the purposes of bidirectional text formatting.
  • wbr represents a line break opportunity.
  • canvas is used for rendering dynamic bitmap graphics on the fly, such as graphs or games.
  • command represents a command the user can invoke.
  • details represents additional information or controls which the user can obtain on demand. The summary element provides its summary, legend, or caption.
  • datalist together with the a new list attribute for input can be used to make comboboxes:
    <input list="browsers">
    <datalist id="browsers">
     <option value="Safari">
     <option value="Internet Explorer">
     <option value="Opera">
     <option value="Firefox">
    </datalist>
  • keygen represents control for key pair generation.
  • output represents some type of output, such as from a calculation done through scripting.

The input element’s type attribute now has the following new values:

The idea of these new types is that the user agent can provide the user interface, such as a calendar date picker or integration with the user’s address book, and submit a defined format to the server. It gives the user a better experience as his input is checked before sending it to the server meaning there is less time to wait for feedback.

For more clickhere