編輯：關於Android編程
本文代碼以MTK平台Android 4.4為分析對象，與Google原生AOSP有些許差異，請讀者知悉。
Android系統通話記錄存儲在聯系人數據庫contacts2.db中的calls表中，通話記錄(calllog)存儲到數據庫的時機可查看我之前的一篇博客Android4.4 Telephony流程分析——電話掛斷step39，系統提供了CallLogProvider這個ContentProvider來供外界訪問。我們來看本文將會使用到的CallLogProvider的代碼片段：
/**
* Call log content provider.
*/
public class CallLogProvider extends ContentProvider {
......
private static final int CALLS_JION_DATA_VIEW = 5;
private static final int CALLS_JION_DATA_VIEW_ID = 6;
......
private static final UriMatcher sURIMatcher = new UriMatcher(UriMatcher.NO_MATCH);
static {
sURIMatcher.addURI(CallLog.AUTHORITY, "calls", CALLS);
sURIMatcher.addURI(CallLog.AUTHORITY, "calls/#", CALLS_ID);
sURIMatcher.addURI(CallLog.AUTHORITY, "calls/filter/*", CALLS_FILTER);
sURIMatcher.addURI(CallLog.AUTHORITY, "calls/search_filter/*", CALLS_SEARCH_FILTER);
sURIMatcher.addURI(CallLog.AUTHORITY, "callsjoindataview", CALLS_JION_DATA_VIEW);
sURIMatcher.addURI(CallLog.AUTHORITY, "callsjoindataview/#", CALLS_JION_DATA_VIEW_ID);
sURIMatcher.addURI(CallLog.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY, SEARCH_SUGGESTIONS);
sURIMatcher.addURI(CallLog.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY + "/*", SEARCH_SUGGESTIONS);
sURIMatcher.addURI(CallLog.AUTHORITY, SearchManager.SUGGEST_URI_PATH_SHORTCUT + "/*", SEARCH_SHORTCUT);
}
private static final HashMap sCallsProjectionMap;
......
private static final String mstableCallsJoinData = Tables.CALLS + " LEFT JOIN "
+ " (SELECT * FROM " + Views.DATA + " WHERE " + Data._ID + " IN "
+ "(SELECT " + Calls.DATA_ID + " FROM " + Tables.CALLS + ")) AS " + Views.DATA
+ " ON(" + Tables.CALLS + "." + Calls.DATA_ID + " = " + Views.DATA + "." + Data._ID + ")";
......
private static final HashMap sCallsJoinDataViewProjectionMap;
......
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
String sortOrder) {
final SQLiteQueryBuilder qb = new SQLiteQueryBuilder();
.......
switch (match) {
......
case CALLS_JION_DATA_VIEW: {
qb.setTables(mstableCallsJoinData);
qb.setProjectionMap(sCallsJoinDataViewProjectionMap);
qb.setStrict(true);
break;
}
case CALLS_JION_DATA_VIEW_ID: {
qb.setTables(mstableCallsJoinData);//將查詢這個數據集合，mstableCallsJoinData前面已定義
qb.setProjectionMap(sCallsJoinDataViewProjectionMap);
qb.setStrict(true);
selectionBuilder.addClause(getEqualityClause(Tables.CALLS + "." + Calls._ID,
parseCallIdFromUri(uri)));
break;
}
......
}
......
}
......
} 
下面是Dialer中通話記錄的加載時序圖，此圖只關注calllog數據的處理:
Dialer模塊是Android4.4之後才獨立處理的，整個模塊大部分的UI顯示都是使用Framgment實現。觸發通話記錄刷新加載的的操作比較多，如Fragment onResume()時、數據庫更新時、選擇了通話記錄過濾等，這些操作都會使用step2的refreshData()方法來查詢數據庫。
step3~step4，刷新通話記錄聯系人圖片緩存，聯系人圖片緩存使用的是LruCache技術，異步加載，後面再發博文分析。
step5，讀取sim卡過濾設置、通話類型設置，開始查詢，
public void startCallsQuery() {
mAdapter.setLoading(true);//step6，正在加載聯系人，此時聯系人列表不顯示為 空
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this.getActivity());
int simFilter = prefs.getInt(Constants.SIM_FILTER_PREF, Constants.FILTER_SIM_DEFAULT);//要查看calllog的SIM卡
int typeFilter = prefs.getInt(Constants.TYPE_FILTER_PREF, Constants.FILTER_TYPE_DEFAULT);//通話類型：來電？去電？未接？全部？
mCallLogQueryHandler.fetchCallsJionDataView(simFilter, typeFilter);
/* add wait cursor */
int count = this.getListView().getCount();
Log.i(TAG, "***********************count : " + count);
mIsFinished = false;
if (0 == count) {//現在列表中記錄為空，顯示等待加載控件
Log.i(TAG, "call sendmessage");
mHandler.sendMessageDelayed(mHandler.obtainMessage(WAIT_CURSOR_START),
WAIT_CURSOR_DELAY_TIME);
}
}step9，設置查詢Uri，
if (QUERY_ALL_CALLS_JOIN_DATA_VIEW_TOKEN == token) {
queryUri = Uri.parse("content://call_log/callsjoindataview");
queryProjection = CallLogQueryEx.PROJECTION_CALLS_JOIN_DATAVIEW;
}CallLogQueryHandlerEx、NoNullCursorAsyncQueryHandler抽象類、AsyncQueryHandler抽象類是繼承關系，繼承自Handler，
AsyncQueryHandler是Framework中提供的異步查詢類，定義在\frameworks\base\cZ喎?/kf/ware/vc/" target="_blank" class="keylink">vcmVcamF2YVxhbmRyb2lkXGNvbnRlbnSjrHN0ZXAxML2rsunRr8frx/O9u7j4y/yjrDxicj4KPC9wPgo8cD48L3A+CjxwcmUgY2xhc3M9"brush:java;"> public void startQuery(int token, Object cookie, Uri uri,
String[] projection, String selection, String[] selectionArgs,
String orderBy) {
// Use the token as what so cancelOperations works properly
Message msg = mWorkerThreadHandler.obtainMessage(token);//mWorkerThreadHandler是WorkerHandler的對象，也是一個Handler，與工作線程通信
msg.arg1 = EVENT_ARG_QUERY;
WorkerArgs args = new WorkerArgs();
args.handler = this;//this即AsyncQueryHandler，用於工作線程返回查詢結果Cursor
args.uri = uri;
args.projection = projection;
args.selection = selection;
args.selectionArgs = selectionArgs;
args.orderBy = orderBy;
args.cookie = cookie;
msg.obj = args;
mWorkerThreadHandler.sendMessage(msg);//查詢將在工作線程中進行
}
step12~step15，工作線程將查詢結果返回給AsyncQueryHandler的handleMessage()處理。
protected class WorkerHandler extends Handler {
public WorkerHandler(Looper looper) {
super(looper);
}
@Override
public void handleMessage(Message msg) {
final ContentResolver resolver = mResolver.get();
if (resolver == null) return;
WorkerArgs args = (WorkerArgs) msg.obj;
int token = msg.what;
int event = msg.arg1;
switch (event) {
case EVENT_ARG_QUERY:
Cursor cursor;
try {
cursor = resolver.query(args.uri, args.projection,
args.selection, args.selectionArgs,
args.orderBy);
// Calling getCount() causes the cursor window to be filled,
// which will make the first access on the main thread a lot faster.
if (cursor != null) {
cursor.getCount();
}
} catch (Exception e) {
Log.w(TAG, "Exception thrown during handling EVENT_ARG_QUERY", e);
cursor = null;
}
args.result = cursor;//查詢結果cursor
break;
......
}
// passing the original token value back to the caller
// on top of the event values in arg1.
Message reply = args.handler.obtainMessage(token); //args.handler就是上文提到的this
reply.obj = args;
reply.arg1 = msg.arg1; //EVENT_ARG_QUERY
reply.sendToTarget();
}
} @Override
protected final void onQueryComplete(int token, Object cookie, Cursor cursor) {
CookieWithProjection projectionCookie = (CookieWithProjection) cookie;
super.onQueryComplete(token, projectionCookie.originalCookie, cursor);
if (cursor == null) {//通話記錄為空，創建一個空的cursor返回
cursor = new EmptyCursor(projectionCookie.projection);
}
onNotNullableQueryComplete(token, projectionCookie.originalCookie, cursor);//step17
} @Override
public void onCallsFetched(Cursor cursor) {
.......
mAdapter.setLoading(false);//與step6對應
mAdapter.changeCursor(cursor);//更改CallLogListAdapter的cursor，刷新ListView
// when dialpadfrangment is in forgoround, not update dial pad menu item.
Activity activity = getActivity();
/// M: for refresh option menu;
activity.invalidateOptionsMenu();
if (mScrollToTop) {
//Modified by Lee 2014-06-30 for flip sms and call start
final HYListView listView = (HYListView)getListView();
//Modified by Lee 2014-06-30 for flip sms and call end
if (listView.getFirstVisiblePosition() > 5) {
listView.setSelection(5);
}
listView.setSelection(0);
mScrollToTop = false;
}
mCallLogFetched = true;
/** M: add :Bug Fix for ALPS00115673 @ { */
Log.i(TAG, "onCallsFetched is call");
mIsFinished = true;
mLoadingContainer.startAnimation(AnimationUtils.loadAnimation(getActivity(),
android.R.anim.fade_out));
mLoadingContainer.setVisibility(View.GONE);
mLoadingContact.setVisibility(View.GONE);
mProgress.setVisibility(View.GONE);
// hide calldetail view,let no call log warning show on all screen
if (mCallDetail != null) {
if (cursor == null || cursor.getCount() == 0) {
mCallDetail.setVisibility(View.GONE);
} else {
mCallDetail.setVisibility(View.VISIBLE);
}
}
mEmptyTitle.setText(R.string.recentCalls_empty);
/** @ }*/
destroyEmptyLoaderIfAllDataFetched();
// send message,the message will execute after the listview inflate
handle.sendEmptyMessage(SETFIRSTTAG); //設置ListView第一條可顯示的數據
}step26中是具體的分組規則、分組過程:
public void addGroups(Cursor cursor) {
final int count = cursor.getCount();
if (count == 0) {
return;
}
int currentGroupSize = 1;
cursor.moveToFirst();
// The number of the first entry in the group.
String firstNumber = cursor.getString(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_NUMBER);
// This is the type of the first call in the group.
int firstCallType = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_CALL_TYPE);
//The following lines are provided and maintained by Mediatek Inc.
int firstSimId = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_SIM_ID);
int firstVtCall = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_VTCALL);
long firstDate = cursor.getLong(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_DATE);
if (0 != cursor.getCount()) {
setGroupHeaderPosition(cursor.getPosition());
}
/// @}
while (cursor.moveToNext()) {
// The number of the current row in the cursor.
final String currentNumber = cursor.getString(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_NUMBER);
final int callType = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_CALL_TYPE);
/// @}
final boolean sameNumber = equalNumbers(firstNumber, currentNumber);
final boolean shouldGroup;
/// M: add @{
final int simId = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_SIM_ID);
final int vtCall = cursor.getInt(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_VTCALL);
final long date = cursor.getLong(CallLogQueryEx.CALLS_JOIN_DATA_VIEW_DATE);
final boolean isSameDay = CallLogDateFormatHelper.isSameDay(firstDate, date);
/// @ }
/// M: [VVM] voice mail should not be grouped.
if (firstCallType == Calls.VOICEMAIL_TYPE || !sameNumber || firstCallType != callType
|| firstSimId != simId || firstVtCall != vtCall || !isSameDay) { //看注釋
// Should only group with calls from the same number, the same
// callType, the same simId and the same vtCall values.
shouldGroup = false; //這個條件下，ListView需要顯示一條記錄
} else {
shouldGroup = true; //同一個group ListView只顯示一條記錄，加上通話記錄數目
}
/// @}
if (shouldGroup) {
// Increment the size of the group to include the current call, but do not create
// the group until we find a call that does not match.
currentGroupSize++; //累加
} else {
// Create a group for the previous set of calls, excluding the current one, but do
// not create a group for a single call.
addGroup(cursor.getPosition() - currentGroupSize, currentGroupSize);
if (!isSameDay) { //不是同一天的通話記錄，需要顯示Header(日期)
setGroupHeaderPosition(cursor.getPosition());
}
/// @}
// Start a new group; it will include at least the current call.
currentGroupSize = 1;
// The current entry is now the first in the group.//上一條記錄為參考值，比較
firstNumber = currentNumber;
firstCallType = callType;
/// M: add @{
firstCallType = callType;
firstSimId = simId;
firstVtCall = vtCall;
firstDate = date;
/// @}
}
}
addGroup(count - currentGroupSize, currentGroupSize);
/// @}
}
public void setGroupHeaderPosition(int cursorPosition) {
mHeaderPositionList.put(Integer.valueOf(cursorPosition), Boolean.valueOf(true));
} protected void addGroup(int cursorPosition, int size, boolean expanded) {
if (mGroupCount >= mGroupMetadata.length) {
int newSize = idealLongArraySize(
mGroupMetadata.length + GROUP_METADATA_ARRAY_INCREMENT);
long[] array = new long[newSize];
System.arraycopy(mGroupMetadata, 0, array, 0, mGroupCount);
mGroupMetadata = array;
}
long metadata = ((long)size << 32) | cursorPosition;
if (expanded) {
metadata |= EXPANDED_GROUP_MASK;
}
mGroupMetadata[mGroupCount++] = metadata;
}
通話記錄ListView和Adapter的數據綁定是在GroupingListAdapter中的getView()方法中，此類繼承自BaseAdapter，來看一下它的繼承結構：
浏覽器中打開即可查看大圖。
未完待續，有不對的地方，請指正。
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