【干货】Android系统定制基础篇：第二部分(Launcher3支持键盘切换焦点、开发者模式密码确认、禁止非预装应用安装、配置时间)

1、Android Launcher3支持键盘切换焦点

Android Launcher3 默认并不支持键盘操作，无法切换焦点，在一些需要支持键盘或遥控操作的设备中无法使用，因些对 Launcher3 做简单修改，使其支持键盘切换焦点。

diff --git a/packages/apps/Launcher3/res/layout/all_apps.xml b/packages/apps/Launcher3/res/layout/all_apps.xml
old mode 100644
new mode 100755
diff --git a/packages/apps/Launcher3/res/layout/all_apps_icon.xml b/packages/apps/Launcher3/res/layout/all_apps_ic
index 3c2f842..1c22ec3 100755
--- a/packages/apps/Launcher3/res/layout/all_apps_icon.xml
+++ b/packages/apps/Launcher3/res/layout/all_apps_icon.xml
@@ -24,5 +24,7 @@
     launcher:iconDisplay="all_apps"
     launcher:centerVertically="true"
     android:paddingLeft="@dimen/dynamic_grid_cell_padding_x"
-    android:paddingRight="@dimen/dynamic_grid_cell_padding_x" />
+    android:paddingRight="@dimen/dynamic_grid_cell_padding_x"
+    android:focusable="true"
+    android:focusableInTouchMode="false" />
 
diff --git a/packages/apps/Launcher3/res/layout/page_indicator.xml b/packages/apps/Launcher3/res/layout/page_indic
old mode 100644
new mode 100755
diff --git a/packages/apps/Launcher3/res/layout/search_container_workspace.xml b/packages/apps/Launcher3/res/layou
old mode 100644
new mode 100755
index 1c617b1..161431f
--- a/packages/apps/Launcher3/res/layout/search_container_workspace.xml
+++ b/packages/apps/Launcher3/res/layout/search_container_workspace.xml
@@ -22,9 +22,11 @@
         android:id="@id/search_container_workspace"
         android:padding="0dp" >
 
-    <fragment
-        android:name="com.android.launcher3.qsb.QsbContainerView$QsbFragment"
-        android:layout_width="match_parent"
-        android:tag="qsb_view"
-        android:layout_height="match_parent"/>
+    <!--Modified by shenhb@topband.com.cn，remove search box.-->
+    <!--<fragment-->
+        <!--android:name="com.android.launcher3.qsb.QsbContainerView$QsbFragment"-->
+        <!--android:layout_width="match_parent"-->
+        <!--android:tag="qsb_view"-->
+        <!--android:layout_height="match_parent"/>-->
+    <!--End of modify-->
 </com.android.launcher3.qsb.QsbContainerView>
\ No newline at end of file
diff --git a/packages/apps/Launcher3/src/com/android/launcher3/Workspace.java b/packages/apps/Launcher3/src/com/an
old mode 100644
new mode 100755
index 6ce3ad6..8a03091
--- a/packages/apps/Launcher3/src/com/android/launcher3/Workspace.java
+++ b/packages/apps/Launcher3/src/com/android/launcher3/Workspace.java
@@ -606,11 +606,13 @@ public class Workspace extends PagedView
                     .inflate(R.layout.search_container_workspace,firstPage, false);
         }
 
+        /* Modified by shenhb@topband.com.cn，remove search box.
         CellLayout.LayoutParams lp = new CellLayout.LayoutParams(0, 0, firstPage.getCountX(), 1);
         lp.canReorder = false;
         if (!firstPage.addViewToCellLayout(qsb, 0, R.id.search_container_workspace, lp, true)) {
             Log.e(TAG, "Failed to add to item at (0, 0) to CellLayout");
         }
+        End of Modify */
     }
 
     public void removeAllWorkspaceScreens() {
diff --git a/packages/apps/Launcher3/src/com/android/launcher3/config/BaseFlags.java b/packages/apps/Launcher3/src
old mode 100644
new mode 100755
index 6a4cbcb..5bc4df8
--- a/packages/apps/Launcher3/src/com/android/launcher3/config/BaseFlags.java
+++ b/packages/apps/Launcher3/src/com/android/launcher3/config/BaseFlags.java
@@ -51,7 +51,7 @@ abstract class BaseFlags {
     // Feature flag to enable moving the QSB on the 0th screen of the workspace.
     public static final boolean QSB_ON_FIRST_SCREEN = true;
     // When enabled the all-apps icon is not added to the hotseat.
-    public static final boolean NO_ALL_APPS_ICON = true;
+    public static final boolean NO_ALL_APPS_ICON = false;
     // When enabled fling down gesture on the first workspace triggers search.
     public static final boolean PULLDOWN_SEARCH = false;
     // When enabled the status bar may show dark icons based on the top of the wallpaper.

2、Android打开开发者模式需要密码确认

在安全性要求比较高的产品中，一般会默认关闭『adb调试』，同时禁止用户打开『adb调试』功能。在Android8.1中默认禁止『adb调试』只需要将下面属性：

persist.sys.usb.config=mtp,adb

改为：

persist.sys.usb.config=mtp

Android默认通过连续点击『版本号』可以打开『开发者选项』，在『开发者选项』中可以打开『adb调试』，所以要禁止用户打开『adb调试』功能，我们在用户点击『版本号』时弹出管理员密码对话框，只有输入正确的管理员密码才可以打开『开发者选项』。修改如下：

diff --git a/packages/apps/Settings/src/com/android/settings/deviceinfo/BuildNumberPreferenceController.java b/pac
index 7a00163..d9b41a4 100755
--- a/packages/apps/Settings/src/com/android/settings/deviceinfo/BuildNumberPreferenceController.java
+++ b/packages/apps/Settings/src/com/android/settings/deviceinfo/BuildNumberPreferenceController.java
@@ -18,17 +18,22 @@ package com.android.settings.deviceinfo;
 
 import android.app.Activity;
 import android.app.Fragment;
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.content.DialogInterface;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Build;
 import android.os.UserHandle;
 import android.os.UserManager;
+import android.os.SystemProperties;
 import android.support.v7.preference.Preference;
 import android.support.v7.preference.PreferenceScreen;
 import android.text.BidiFormatter;
 import android.text.TextUtils;
 import android.util.Pair;
 import android.widget.Toast;
+import android.widget.EditText;
 
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
 import com.android.settings.R;
@@ -63,6 +68,9 @@ public class BuildNumberPreferenceController extends AbstractPreferenceControlle
     private boolean mDebuggingFeaturesDisallowedBySystem;
     private int mDevHitCountdown;
     private boolean mProcessingLastDevHit;
+    
+    private boolean isAuthenticated = false;
+    private Dialog mPasswordDialog;
 
     public BuildNumberPreferenceController(Context context, Activity activity, Fragment fragment,
             Lifecycle lifecycle) {
@@ -114,7 +122,34 @@ public class BuildNumberPreferenceController extends AbstractPreferenceControlle
 
     @Override
     public boolean handlePreferenceTreeClick(Preference preference) {
-        /*
+        final String password = SystemProperties.get("ro.topband.password", "");
+        if (!isAuthenticated && !TextUtils.isEmpty(password) 
+            && (mPasswordDialog == null || !mPasswordDialog.isShowing())) {
+            EditText editText = new EditText(mContext);
+            mPasswordDialog = new AlertDialog.Builder(mContext)
+                .setTitle(R.string.password_dialog_title)
+                .setView(editText)
+                .setPositiveButton(R.string.dialog_ok, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        String text = editText.getText().toString();
+                        if (TextUtils.equals(text, password)) {
+                            isAuthenticated = true;
+                        } else {
+                            Toast.makeText(mContext, R.string.password_error, Toast.LENGTH_SHORT).show();
+                        }
+                    }
+                })
+                .setNegativeButton(R.string.dialog_cancel, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int i) {
+                        dialog.dismiss();
+                    }
+                }).create();
+            mPasswordDialog.show();
+            return false;
+        }
+
         if (!TextUtils.equals(preference.getKey(), KEY_BUILD_NUMBER)) {
             return false;
         }
@@ -191,7 +226,6 @@ public class BuildNumberPreferenceController extends AbstractPreferenceControlle
                     Pair.create(MetricsEvent.FIELD_SETTINGS_BUILD_NUMBER_DEVELOPER_MODE_ENABLED,
                             1));
         }
-        */
         return true;
     }

弹窗预览：
在这里插入图片描述密码通过下面属性配置：

ro.topband.password=123456

3、Android禁止非预装应用安装

禁止非预装应用安装，应用安装时提取文件包名，判断系统是否有预装此应用，如果没有预装则结束安装流程。此方案修改 PackageInstaller，不影响adb安装应用。

合入下面修改前请先合入 Android静默安装这次修改，因为两者共用了从provider Uri中提取文件路径的方法。

diff --git a/packages/apps/PackageInstaller/src/com/android/packageinstaller/InstallStart.java b/packages/apps/Pac
index cbf8c41..2edf99b 100755
--- a/packages/apps/PackageInstaller/src/com/android/packageinstaller/InstallStart.java
+++ b/packages/apps/PackageInstaller/src/com/android/packageinstaller/InstallStart.java
@@ -116,6 +116,15 @@ public class InstallStart extends Activity {
             }
         }
 
+        if (TextUtils.equals(SystemProperties.get("ro.unallow_install", "0"), "1")) {
+            if (!isPreInstallApp(path)) {
+                Log.w(LOG_TAG, "The app is not allowed to be installed without pre-installed.");
+                setResult(RESULT_CANCELED);
+                finish();
+                return;
+            }
+        }
+
         if (isSilentInstall(intent, path)) {
             Log.i(LOG_TAG, "silent install path: " + path);
             getPackageManager().installPackage(Uri.fromFile(new File(path)),
@@ -369,4 +378,29 @@ public class InstallStart extends Activity {
             Log.i(LOG_TAG, packageName + " silent installed.");
         }
     }
+
+    private boolean isPreInstallApp(String path) {
+        Log.i(LOG_TAG, "isPreInstallApp, path=" + path);
+
+        PackageInfo pi = null;
+        if (!TextUtils.isEmpty(path)) {
+            File sourceFile = new File(path);
+            PackageParser.Package parsed = PackageUtil.getPackageInfo(this, sourceFile);
+            if (parsed != null) {
+                PackageInfo pkgInfo = PackageParser.generatePackageInfo(parsed, null,
+                        PackageManager.GET_PERMISSIONS, 0, 0, null,
+                        new PackageUserState());
+                if (pkgInfo != null) {
+                    try {
+                        PackageManager pm = getApplicationContext().getPackageManager();
+                        pi = pm.getPackageInfo(pkgInfo.packageName, 0);
+                    } catch (Exception e) {
+                        Log.w(LOG_TAG, "isPreInstallAPp, error: " + e.getMessage());
+                    }
+                }
+            }
+        }
+
+        return (pi != null);
+    }
 }

属性：

# 禁止非预装应用安装，0：允许，1：禁止
ro.unallow_install=1

4、Android配置初始时间

Android默认初始时间是1970年，首次开机后通过网络同步时间。有时候我们期望默认时间为最近时间，因此通过下面修改来定制通过属性『ro.earliest_time』配置Android初始时间。

diff --git a/frameworks/base/services/java/com/android/server/SystemServer.java b/frameworks/base/services/java/co
index a7bc916..a96f881 100755
--- a/frameworks/base/services/java/com/android/server/SystemServer.java
+++ b/frameworks/base/services/java/com/android/server/SystemServer.java
@@ -50,6 +50,7 @@ import android.util.DisplayMetrics;
 import android.util.EventLog;
 import android.util.Slog;
 import android.view.WindowManager;
+import android.text.TextUtils;
 
 import com.android.internal.R;
 import com.android.internal.app.NightDisplayController;
@@ -145,7 +146,7 @@ public final class SystemServer {
 
     // The earliest supported time.  We pick one day into 1970, to
     // give any timezone code room without going into negative time.
-    private static final long EARLIEST_SUPPORTED_TIME = 86400 * 1000;
+    private static final long EARLIEST_SUPPORTED_TIME = 1577836800L * 1000; //2020-01-01 08:00:00 // 86400 * 1000
 
     /*
      * Implementation class names. TODO: Move them to a codegen class or load
@@ -280,14 +281,6 @@ public final class SystemServer {
     private void run() {
         try {
             traceBeginAndSlog("InitBeforeStartServices");
-            // If a device's clock is before 1970 (before 0), a lot of
-            // APIs crash dealing with negative numbers, notably
-            // java.io.File#setLastModified, so instead we fake it and
-            // hope that time from cell towers or NTP fixes it shortly.
-            if (System.currentTimeMillis() < EARLIEST_SUPPORTED_TIME) {
-                Slog.w(TAG, "System clock is before 1970; setting to 1970.");
-                SystemClock.setCurrentTimeMillis(EARLIEST_SUPPORTED_TIME);
-            }
 
             //
             // Default the timezone property to GMT if not set.
@@ -393,6 +386,23 @@ public final class SystemServer {
             startCoreServices();
             startOtherServices();
             SystemServerInitThreadPool.shutdown();
+            
+            // Modify by ayst.shen@foxmail.com, for configure the initial time.
+            // If a device's clock is before 1970 (before 0), a lot of
+            // APIs crash dealing with negative numbers, notably
+            // java.io.File#setLastModified, so instead we fake it and
+            // hope that time from cell towers or NTP fixes it shortly.
+            long earliestTime = EARLIEST_SUPPORTED_TIME;
+            String earliestTimeStr = SystemProperties.get("ro.earliest_time", "");
+            if (!TextUtils.isEmpty(earliestTimeStr)) {
+                earliestTime = Long.parseLong(earliestTimeStr);
+            }
+            Slog.i(TAG, "Earliest supported time: " + earliestTime);
+            if (System.currentTimeMillis() < earliestTime) {
+                Slog.w(TAG, "System clock is before 1970; setting to 1970.");
+                SystemClock.setCurrentTimeMillis(earliestTime);
+            }
+            // Modify the end
         } catch (Throwable ex) {
             Slog.e("System", "******************************************");
             Slog.e("System", "************ Failure starting system services", ex);

配置属性
通过在线时间戳转换工具将目标日期转为时间戳，比如日期：2020-01-01 08:00:00，转换为时间戳：1577836800000。

# 2020-01-01 08:00:00
ro.earliest_time=1577836800000