Android 系统（125）---Android通过Dialer实现暗码启动

Android通过Dialer实现暗码启动

目前接触比较多的就是通过dialer应用来启动/触发暗码。

本文以Dialer为例，

1.经过调试定位，发现拨号盘接对应的Activity为DialtactsActivity。

2.DialtactsActivity中有个showDialpadFragment方法，用来加载显示拨号盘，因为有可能此时拨号盘正处于收缩/隐藏状态。

/**
 * Initiates a fragment transaction to show the dialpad fragment. Animations and other visual
 * updates are handled by a callback which is invoked after the dialpad fragment is shown.
 * @see #onDialpadShown
 */
private void showDialpadFragment(boolean animate) {
    if (mIsDialpadShown || mStateSaved) {
        return;
    }
    mIsDialpadShown = true;

    mListsFragment.setUserVisibleHint(false);

    final FragmentTransaction ft = getFragmentManager().beginTransaction();
    if (mDialpadFragment == null) {
        mDialpadFragment = new DialpadFragment();
        ft.add(R.id.dialtacts_container, mDialpadFragment, TAG_DIALPAD_FRAGMENT);
    } else {
        ft.show(mDialpadFragment);
    }

    //mDialpadFragment.setAnimate(animate);
    AnalyticsUtil.sendScreenView(mDialpadFragment);
    ft.commit();
    maybeEnterSearchUi();
    if (animate) {
        mFloatingActionButtonController.scaleOut();
    } else {
        mFloatingActionButtonController.setVisible(false);
    }
    mActionBarController.onDialpadUp();

    mListsFragment.getView().animate().alpha(0).withLayer();
}

3.接下来重点处理实现就在DialpapFragment中，首先来看类的声明/继承。

import com.android.dialer.dialpad.DialpadFragment;

/**
 * Fragment that displays a twelve-key phone dialpad.
 */
public class DialpadFragment extends Fragment
        implements View.OnClickListener,
        View.OnLongClickListener, View.OnKeyListener,
        AdapterView.OnItemClickListener, TextWatcher,
        PopupMenu.OnMenuItemClickListener,
        DialpadKeyButton.OnPressedListener,
        /// M: add for plug-in @{
        DialpadExtensionAction {

从以上类实现/继承中可以发现，其继承了TextWatcher类，也正是这个类使之能够监听实现输入变化。

TextWatcher有3个重要方法，分别为：beforeTextChanged，onTextChanged和afterTextChanged。分别看下面那份源码。

onTextChanged

其中最重点的是afterTextChanged方法，其调用了SpecialCharSequenceMgr辅助工具类的handleChars方法。

4.handleChars方法中，会对各种特殊的secret code进行匹配处理。

public static boolean handleChars(Context context, String input, EditText textField) {
    //get rid of the separators so that the string gets parsed correctly
    String dialString = PhoneNumberUtils.stripSeparators(input);
    if (handleDeviceIdDisplay(context, dialString) //*#06#
            || handleRegulatoryInfoDisplay(context, dialString)
            || handlePinEntry(context, dialString)
            || handleAdnEntry(context, dialString, textField)
            || handleSecretCode(context, dialString) //for the form of *#*##*#*.

5.接下来分开两种讲，一种是直接弹出对话框的那种，类如*#06#，另一种则是调起别的应用等方式。
5.1 ）*#*##*#*

/**
 * Handles secret codes to launch arbitrary activities in the form of *#*##*#*.

有以上代码可知，最终是通过broadcast发送出去的，并往intent里面加载了2种数据：Uri和Action。

Action：

private static final String SECRET_CODE_ACTION = "android.provider.Telephony.SECRET_CODE";

接受端的注册方式，Action 和 data必须和发送的broadcast相匹配才行：

/vendor/mediatek/proprietary/packages/apps/EngineerMode/AndroidManifest.xml

<receiver
    android:name=".EngineerModeReceiver"
    android:exported="true" >
    <intent-filter>
        <action android:name="android.provider.Telephony.SECRET_CODE" />
        <data
            android:host="3646633"
            android:scheme="android_secret_code" />
    intent-filter>
receiver>

/vendor/mediatek/proprietary/packages/apps/EngineerMode/src/com/mediatek/engineermode/EngineerModeReceiver.java

由上面代码可知，这就对应上了，在Receiver接受到广播后，启动对应的应用/Activity来处理接下来的工作。

5.2 ）*#06#  直接在Context中弹出对话框,显示IMEI信息

/packages/apps/Dialer/src/com/android/dialer/SpecialCharSequenceMgr.java

// TODO: Use TelephonyCapabilities.getDeviceIdLabel() to get the device id label instead of a
// hard-coded string.
static boolean handleDeviceIdDisplay(Context context, String input) {
    TelephonyManager telephonyManager =
            (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);

    if (telephonyManager != null && input.equals(MMI_IMEI_DISPLAY)) {
        int labelResId = (telephonyManager.getPhoneType() == TelephonyManager.PHONE_TYPE_GSM) ?
                R.string.imei : R.string.meid;

        List deviceIds = new ArrayList();
        if (TelephonyManagerCompat.getPhoneCount(telephonyManager) > 1 &&
                CompatUtils.isMethodAvailable(TelephonyManagerCompat.TELEPHONY_MANAGER_CLASS,
                        "getDeviceId", Integer.TYPE)) {
            for (int slot = 0; slot < telephonyManager.getPhoneCount(); slot++) {
                String deviceId = telephonyManager.getDeviceId(slot);
                if (!TextUtils.isEmpty(deviceId)) {
                    deviceIds.add(deviceId);
                }
            }
        } else {
            deviceIds.add(telephonyManager.getDeviceId());
        }

        AlertDialog alert = new AlertDialog.Builder(context)
                .setTitle(labelResId)
                .setItems(deviceIds.toArray(new String[deviceIds.size()]), null)
                .setPositiveButton(android.R.string.ok, null)
                .setCancelable(false)
                .show();///直接在Context中弹出对话框,显示IMEI信息
        return true;
    }
    return false;
}

*#07# 直接通过隐式intent启动相关应用

private static boolean handleRegulatoryInfoDisplay(Context context, String input) {
    if (input.equals(MMI_REGULATORY_INFO_DISPLAY)) {
        Log.d(TAG, "handleRegulatoryInfoDisplay() sending intent to settings app");
        Intent showRegInfoIntent = new Intent(Settings.ACTION_SHOW_REGULATORY_INFO);
        try {
            context.startActivity(showRegInfoIntent);
        } catch (ActivityNotFoundException e) {
            Log.e(TAG, "startActivity() failed: " + e);
        }
        return true;
    }
    return false;
}

以上就是Android通过Dialer方式启动暗码的大致源码流程分析。