Add Random posts Widget to blogger :
When you making regular posts in your blog the visitor visit new post and ignore old posts so for we have way to show your old posts on side bar of your blog by adding a gadget.So this process will occur in few steps:
1st Step:
First of all open your blog dashboard and then click on Layout and then click on Add a Gadget2nd Step:
In second step Add new HTML/JavaScript Gadget as given below.3rd Step:
In the third step Add the following HTML Code in your Gadget HTML box .<style>
#random-posts img{float:left;margin-right:10px;
width:65px;height:50px;background-color: #F5F5F5;padding: 3px;}
ul#random-posts {list-style-type: none;}
</style>
<ul id='random-posts'>
<script type='text/javaScript'>
var rdp_numposts=5;
var rdp_snippet_length=150;
var rdp_info='yes';
var rdp_comment='Comments';
var rdp_disable='Comments Disabled';
var rdp_current=[];var rdp_total_posts=0;var rdp_current=new Array(rdp_numposts);function totalposts(json){rdp_total_posts=json.feed.openSearch$totalResults.$t}document.write('<script type=\"text/javascript\" src=\"/feeds/posts/default?alt=json-in-script&max-results=0&callback=totalposts\"><\/script>');function getvalue(){for(var i=0;i<rdp_numposts;i++){var found=false;var rndValue=get_random();for(var j=0;j<rdp_current.length;j++){if(rdp_current[j]==rndValue){found=true;break}};if(found){i--}else{rdp_current[i]=rndValue}}};function get_random(){var ranNum=1+Math.round(Math.random()*(rdp_total_posts-1));return ranNum};
</script>
<script type='text/javaScript'>
function random_posts(json){for(var i=0;i<rdp_numposts;i++){var entry=json.feed.entry[i];var rdp_posttitle=entry.title.$t;if('content'in entry){var rdp_get_snippet=entry.content.$t}else{if('summary'in entry){var rdp_get_snippet=entry.summary.$t}else{var rdp_get_snippet="";}};rdp_get_snippet=rdp_get_snippet.replace(/<[^>]*>/g,"");if(rdp_get_snippet.length<rdp_snippet_length){var rdp_snippet=rdp_get_snippet}else{rdp_get_snippet=rdp_get_snippet.substring(0,rdp_snippet_length);var space=rdp_get_snippet.lastIndexOf(" ");rdp_snippet=rdp_get_snippet.substring(0,space)+"…";};for(var j=0;j<entry.link.length;j++){if('thr$total'in entry){var rdp_commentsNum=entry.thr$total.$t+' '+rdp_comment}else{rdp_commentsNum=rdp_disable};if(entry.link[j].rel=='alternate'){var rdp_posturl=entry.link[j].href;var rdp_postdate=entry.published.$t;if('media$thumbnail'in entry){var rdp_thumb=entry.media$thumbnail.url}else{rdp_thumb="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLyaHQhT00vvPonsiGqOfi92dkXd4gff5hMprJA3sYD0YjUZQlENWcFtiT8zssor1oNCv-5v0Mr-EmBq_gWCn253KFY3AqQZp4VL1ImqabuKpc6BCHBGe57rAtvRLX8nPQGFSnzvblbbs/s1600/no_thumb.png"}}};document.write('<li>');document.write('<img alt="'+rdp_posttitle+'" src="'+rdp_thumb+'"/>');document.write('<div><a href="'+rdp_posturl+'" rel="nofollow" title="'+rdp_snippet+'">'+rdp_posttitle+'</a></div>');if(rdp_info=='yes'){document.write('<span>'+rdp_postdate.substring(8,10)+'/'+rdp_postdate.substring(5,7)+'/'+rdp_postdate.substring(0,4)+' - '+rdp_commentsNum)+'</span>'}document.write('<div style="clear:both"></div></li>')}};getvalue();for(var i=0;i<rdp_numposts;i++){document.write('<script type=\"text/javascript\" src=\"/feeds/posts/default?alt=json-in-script&start-index='+rdp_current[i]+'&max-results=1&callback=random_posts\"><\/script>')};
</script>
</ul>
In the given HTML code The 5 represent the Number of post that you want to show in the Gadget .
And the width; 65px and height; 50px is for the size of the thumbnail size of the post that you can change .
4th Step:
In this step click on save button and the the gadget is displayed .If you have any problem about this you can comments below...
Thank you !