LinkEnabledTextView.java

package com.moupress.app.friendshost.uicomponent;

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.text.Spannable;
import android.text.SpannableString;
import android.text.style.ClickableSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.widget.TextView;

import com.moupress.app.friendshost.ui.listeners.TextLinkClickListener;
import com.moupress.app.friendshost.util.StringUtil;

public class LinkEnabledTextView  extends TextView {
	private static final String TAG = "LinkEnabledTextView";

	// The String Containing the Text that we have to gather links from private SpannableString linkableText;
	// Populating and gathering all the links that are present in the Text
	private ArrayList<Hyperlink> listOfLinks; 
	
	// A Listener Class for generally sending the Clicks to the one which requires it
	TextLinkClickListener mListener;
	
	// Pattern for gathering @usernames from the Text
	Pattern screenNamePattern = Pattern.compile("( @[a-zA-Z0-9_]+)");
	
	// Pattern for gathering #hasttags from the Text
	Pattern hashTagsPattern = Pattern.compile("( #[a-zA-Z0-9_-]+)");
	
	// Pattern for gathering http:// links from the Text
	Pattern hyperLinksPattern = Pattern.compile("(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]");
	
	// Pattern for Renren Feed Type 分享相册， 分享日志
	Pattern renrenFeedTypePattern = Pattern.compile("(分享了|上传了|转自)(日志|照片|相册)?:");

	private Spannable linkableText;
	
	public boolean IsLinkedTxtClicked = false;

	public LinkEnabledTextView(Context context, AttributeSet attrs) {
	    super(context, attrs);
	    listOfLinks = new ArrayList<Hyperlink>();
	}

	public void gatherLinksForText(String text) {
		// replace malformed text
		ArrayList<String> urls = StringUtil.retrieveURL(text);
		for (String url:urls) {
			text = text.replace(url, url + " ");
		}
		
	    linkableText = new SpannableString(text);
	    /*
	     *  gatherLinks basically collects the Links depending upon the Pattern that we supply
	     *  and add the links to the ArrayList of the links
	     */
	    listOfLinks = new ArrayList<Hyperlink>();
	    gatherLinks(listOfLinks, linkableText, screenNamePattern);
	    gatherLinks(listOfLinks, linkableText, hashTagsPattern);
	    gatherLinks(listOfLinks, linkableText, hyperLinksPattern);
	    //gatherLinks(listOfLinks, linkableText, renrenFeedTypePattern);
	
	    try {
	    	for(int i = 0; i< listOfLinks.size(); i++) {
		        Hyperlink linkSpec = listOfLinks.get(i);
		        android.util.Log.v("listOfLinks :: " + linkSpec.textSpan, "listOfLinks :: " + linkSpec.textSpan);
		        // this process here makes the Clickable Links from the text
		        linkableText.setSpan(linkSpec.span, linkSpec.start, linkSpec.end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
		    }
	    } catch (IndexOutOfBoundsException e) {
	    	Log.e(TAG, "Link Text Index out of bounds:" + text);
	    }
	    // sets the text for the TextView with enabled links
	    setText(linkableText);
	}

	/*
	 * sets the Listener for later click propagation purpose
	 */
	public void setOnTextLinkClickListener(TextLinkClickListener newListener) {
	    mListener = newListener;
	}

/*
 * The Method mainly performs the Regex Comparison for the Pattern and adds them to
 * listOfLinks array list
 */

	private final void gatherLinks(ArrayList<Hyperlink> links, Spannable s, Pattern pattern) {
	    // Matcher matching the pattern
	    Matcher m = pattern.matcher(s);
	    while (m.find()) {
	        int start = m.start();
	        int end = m.end();
	
	        /*
	         *  Hyperlink is basically used like a structure for storing the information about
	         *  where the link was found.
	         */
	        Hyperlink spec = new Hyperlink();
	
	        spec.textSpan = s.subSequence(start, end);
	        spec.span = new InternalURLSpan(spec.textSpan.toString());
	        spec.start = start;
	        spec.end = end;
	
	        links.add(spec);
	    }
	}

	/*
	 * This is class which gives us the clicks on the links which we then can use.
	 */
	public class InternalURLSpan extends ClickableSpan {
	    private String clickedSpan;
	
	    public InternalURLSpan (String clickedString) {
	        clickedSpan = clickedString;
	    }
	
	    @Override
	    public void onClick(View textView) {
	    	IsLinkedTxtClicked = true;
	        mListener.onTextLinkClick(textView, clickedSpan);
	    }
	}

	/*
	 * Class for storing the information about the Link Location
	 */
	
	class Hyperlink {
	    CharSequence textSpan;
	    InternalURLSpan span;
	    int start;
	    int end;
	}
}