Android SMS and MMS exploring threads

Android Source Code adds a trigger in the mms sms table and the mms pdu table.

CREATE TRIGGER delete_obsolete_threads_pdu AFTER DELETE ON pdu BEGIN   DELETE FROM threads   WHERE     _id = old.thread_id     AND _id NOT IN     (SELECT thread_id FROM sms      UNION SELECT thread_id from pdu); END

If the threads table does not have an external reference of SMS or pdu, the thread will be deleted.

After the thread is deleted, you can insert a text message or MMS Message (of course, the code is inserted). This will not be displayed because there is no thread ID.

Some people may think that it is not enough to maintain the threads table together? Unfortunately, the system does not fully enable providers for this table and can only be used for searching.

But we need thread_id again at this time. I made some modifications to the source code and extracted the Thread class for your reference only.

package com.sweetop.provider;import java.util.HashSet;import java.util.Set;import java.util.regex.Matcher;import java.util.regex.Pattern;import android.content.Context;import android.database.Cursor;import android.net.Uri;import android.text.TextUtils;import android.util.Log;import android.util.Patterns;public final class Threads implements ThreadsColumns {private static final String[] ID_PROJECTION = { BaseColumns._ID };private static final String STANDARD_ENCODING = "UTF-8";private static final Uri THREAD_ID_CONTENT_URI = Uri.parse("content://mms-sms/threadID");public static final Uri CONTENT_URI = Uri.withAppendedPath(Uri.parse("content://mms-sms/"), "conversations");public static final Uri OBSOLETE_THREADS_URI = Uri.withAppendedPath(CONTENT_URI, "obsolete");public static final Pattern NAME_ADDR_EMAIL_PATTERN = Pattern.compile("\\s*(\"[^\"]*\"|[^<>\"]+)\\s*<([^<>]+)>\\s*");public static final int COMMON_THREAD = 0;public static final int BROADCAST_THREAD = 1;// No one should construct an instance of this class.private Threads() {}/** * This is a single-recipient version of getOrCreateThreadId. It's * convenient for use with SMS messages. */public static long getOrCreateThreadId(Context context, String recipient) {Set<String> recipients = new HashSet<String>();recipients.add(recipient);return getOrCreateThreadId(context, recipients);}/** * Given the recipients list and subject of an unsaved message, return its * thread ID. If the message starts a new thread, allocate a new thread ID. * Otherwise, use the appropriate existing thread ID. *  * Find the thread ID of the same set of recipients (in any order, without * any additions). If one is found, return it. Otherwise, return a unique * thread ID. */public static long getOrCreateThreadId(Context context,Set<String> recipients) {Uri.Builder uriBuilder = THREAD_ID_CONTENT_URI.buildUpon();for (String recipient : recipients) {if (isEmailAddress(recipient)) {recipient = extractAddrSpec(recipient);}uriBuilder.appendQueryParameter("recipient", recipient);}Uri uri = uriBuilder.build();// if (DEBUG) Log.v(TAG, "getOrCreateThreadId uri: " + uri);Cursor cursor = context.getContentResolver().query(uri, ID_PROJECTION,null, null, null);if (true) {Log.v("Threads","getOrCreateThreadId cursor cnt: " + cursor.getCount());}if (cursor != null) {try {if (cursor.moveToFirst()) {return cursor.getLong(0);} else {Log.e("Threads", "getOrCreateThreadId returned no rows!");}} finally {cursor.close();}}Log.e("Threads","getOrCreateThreadId failed with uri " + uri.toString());throw new IllegalArgumentException("Unable to find or allocate a thread ID.");}public static String extractAddrSpec(String address) {Matcher match = NAME_ADDR_EMAIL_PATTERN.matcher(address);if (match.matches()) {return match.group(2);}return address;}/** * Returns true if the address is an email address *  * @param address *            the input address to be tested * @return true if address is an email address */public static boolean isEmailAddress(String address) {if (TextUtils.isEmpty(address)) {return false;}String s = extractAddrSpec(address);Matcher match = Patterns.EMAIL_ADDRESS.matcher(s);return match.matches();}}

To obtain a thread ID, you only need to call

Threads.getOrCreateThreadId(this, address)

Address is the sender's mobile phone address.

If you have any questions, please comment again and I will reply one by one.

In addition, reprinted and indicated the source