【Launcher3系列】Android 11 长按图标操作卸载，去掉顶部卸载、移除

1. 概述

Android系统的Launcher改造在国内算是一个不算很低频的需求，尤其是相当多的三方硬件设备以及部分手机厂商的个性化ROM等，受限于国内整体的开源环境，网上能找到相关的开发资源并不多，最近公司有相关业务需求的开发，就自己涉及到的改造点作一些分享。

原生Launcher自带的长按图标快捷操作区是“应用信息”、“微件”以及其它一些个性化支持操作，而通常需求方出于方便操作及简化用户理解的考虑，希望改造补充“卸载”，且大多同时希望去掉拖动图标时显示在顶部的“卸载、移除”，涉及到的改动点如下：

• 在长按快捷区增加”卸载“

• 移除拖动icon时顶部的卸载布局及边界框

• 不显示顶部的“卸载、移除”

2. 涉及到的类及接口等

在长按快捷区增加”卸载“

com.android.launcher3.Launcher
com.android.launcher3.popup.SystemShortcut
com.android.launcher3.popup.PopupContainerWithArrow
string.xml

移除拖动icon时顶部的卸载布局及边界框

com.android.launcher3.Workspace

不显示顶部的“卸载、移除”

com.android.launcher3.Launcher

3. Show the code

• 在长按快捷区增加”卸载“

  参考APP_INFO内部对象，创建UNINSTALL对象，并添加相应的卸载处理，参考SecondaryDropTarget的performDropAction方法改写。并在string.xml中添加

  <string name="app_info_drop_uninstall_label">卸载string>
  

  SystemShortcut.java

      public static final Factory<BaseDraggingActivity> APP_INFO = AppInfo::new;
  
      public static class AppInfo extends SystemShortcut {
  
          // ... //
      }
  
  //====修改start==== 创建UNINSTALL内部对象
      public static final Factory<BaseDraggingActivity> UNINSTALL = UnInstall::new;
  
      public static class UnInstall extends SystemShortcut {
  
          public UnInstall(BaseDraggingActivity target, ItemInfo itemInfo) {
              super(R.drawable.ic_uninstall_no_shadow, R.string.app_info_drop_uninstall_label, target,
                      itemInfo);
          }
  
          @Override
          public void onClick(View view) {
              dismissTaskMenuView(mTarget);
              ComponentName cn = getUninstallTarget(mItemInfo);
              if (cn == null) {
                  // System applications cannot be installed. For now, show a toast explaining that.
                  // We may give them the option of disabling apps this way.
                  Toast.makeText(mTarget, R.string.uninstall_system_app_text, Toast.LENGTH_SHORT).show();
                  return;
              }
              try {
                  Intent i = Intent.parseUri(mTarget.getString(R.string.delete_package_intent), 0)
                          .setData(Uri.fromParts("package", cn.getPackageName(), cn.getClassName()))
                          .putExtra(Intent.EXTRA_USER, mItemInfo.user);
                  mTarget.startActivity(i);
                  FileLog.d("Uninstall", "start uninstall activity " + cn.getPackageName());
                  return;
              } catch (URISyntaxException e) {
                  Log.e("Uninstall", "Failed to parse intent to start uninstall activity for item=" + mItemInfo);
                  return;
              }
          }
      }
  
      /**
       * @return the component name that should be uninstalled or null.
       */
      ComponentName getUninstallTarget(ItemInfo item) {
          Intent intent = null;
          UserHandle user = null;
          if (item != null &&
                  item.itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION) {
              intent = item.getIntent();
              user = item.user;
          }
          if (intent != null) {
              LauncherActivityInfo info = mTarget.getSystemService(LauncherApps.class)
                      .resolveActivity(intent, user);
              if (info != null
                      && (info.getApplicationInfo().flags & ApplicationInfo.FLAG_SYSTEM) == 0) {
                  return info.getComponentName();
              }
          }
          return null;
      }
  //====修改end====
  
      public static final Factory<BaseDraggingActivity> INSTALL = (activity, itemInfo) -> {
          // ... //
      };
  

  Launcher.java

      public Stream<SystemShortcut.Factory> getSupportedShortcuts() {
  //====修改==== 添加UNINSTALL
          return Stream.of(APP_INFO, WIDGETS,INSTALL,UNINSTALL);
      }
  

  PopupContainerWithArrow.java

  public class PopupContainerWithArrow<T extends BaseDraggingActivity> extends ArrowPopup<T>
          implements DragSource, DragController.DragListener {
  
      // ... //
  
      @TargetApi(Build.VERSION_CODES.P)
      public void populateAndShow(final BubbleTextView originalIcon, int shortcutCount,
              final List<NotificationKeyData> notificationKeys, List<SystemShortcut> systemShortcuts) {
          mNumNotifications = notificationKeys.size();
          mOriginalIcon = originalIcon;
  
  //====修改==== 将hasDeepShortcuts置为false,以屏蔽部分APP额外支持的快捷操
          boolean hasDeepShortcuts = false;//shortcutCount > 0;
          int containerWidth = (int) getResources().getDimension(R.dimen.bg_popup_item_width);
  
          // if there are deep shortcuts, we might want to increase the width of shortcuts to fit
          // horizontally laid out system shortcuts.
          //hasDeepShortcuts表示该图标是否还有快捷操作，比如时钟APP还有快捷的"启动屏保、启支秒表"等
          if (hasDeepShortcuts) {
              containerWidth = (int) Math.max(containerWidth,
                      systemShortcuts.size() * getResources().getDimension(
                              R.dimen.system_shortcut_header_icon_touch_size));
          }
          // Add views
          if (mNumNotifications > 0) {
              // Add notification entries
              View.inflate(getContext(), R.layout.notification_content, this);
              mNotificationItemView = new NotificationItemView(this);
              if (mNumNotifications == 1) {
                  mNotificationItemView.removeFooter();
              }
              else {
                  mNotificationItemView.setFooterWidth(containerWidth);
              }
              updateNotificationHeader();
          }
          int viewsToFlip = getChildCount();
          mSystemShortcutContainer = this;
          //有快捷操作才进，咱不进
          if (hasDeepShortcuts) {
              if (mNotificationItemView != null) {
                  mNotificationItemView.addGutter();
              }
  
              for (int i = shortcutCount; i > 0; i--) {
                  DeepShortcutView v = inflateAndAdd(R.layout.deep_shortcut, this);
                  v.getLayoutParams().width = containerWidth;
                  mShortcuts.add(v);
              }
              updateHiddenShortcuts();
  
              if (!systemShortcuts.isEmpty()) {
                  mSystemShortcutContainer = inflateAndAdd(R.layout.system_shortcut_icons, this);
                  for (SystemShortcut shortcut : systemShortcuts) {
                      initializeSystemShortcut(
                              R.layout.system_shortcut_icon_only, mSystemShortcutContainer, shortcut);
                  }
              }
          } else if (!systemShortcuts.isEmpty()) {
              if (mNotificationItemView != null) {
                  mNotificationItemView.addGutter();
              }
  
              for (SystemShortcut shortcut : systemShortcuts) {
                  //这里是长按图标后弹出的操作项item样式
  //====修改start==== 添加快捷操作过滤，如果想保留“应用信息”，可同理处理
                  if(shortcut instanceof SystemShortcut.UnInstall){
                      initializeSystemShortcut(R.layout.system_shortcut, this, shortcut);
                  }
  //====修改end====
              }
          }
  
          reorderAndShow(viewsToFlip);
  
          ItemInfo originalItemInfo = (ItemInfo) originalIcon.getTag();
          if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
              setAccessibilityPaneTitle(getTitleForAccessibility());
          }
  
          mOriginalIcon.setForceHideDot(true);
  
          // All views are added. Animate layout from now on.
          setLayoutTransition(new LayoutTransition());
  
          // Load the shortcuts on a background thread and update the container as it animates.
          MODEL_EXECUTOR.getHandler().postAtFrontOfQueue(PopupPopulator.createUpdateRunnable(
                  mLauncher, originalItemInfo, new Handler(Looper.getMainLooper()),
                  this, mShortcuts, notificationKeys));
      }
  
      // ... //
  
      /**
       * Utility class to handle updates while the popup is visible (like widgets and
       * notification changes)
       */
      private class LiveUpdateHandler implements
              PopupDataChangeListener, View.OnAttachStateChangeListener {
  
          private final Launcher mLauncher;
  
          LiveUpdateHandler(Launcher launcher) {
              mLauncher = launcher;
          }
  
          @Override
          public void onViewAttachedToWindow(View view) {
              mLauncher.getPopupDataProvider().setChangeListener(this);
          }
  
          @Override
          public void onViewDetachedFromWindow(View view) {
              mLauncher.getPopupDataProvider().setChangeListener(null);
          }
  
          @Override
          public void onWidgetsBound() {
              ItemInfo itemInfo = (ItemInfo) mOriginalIcon.getTag();
              SystemShortcut widgetInfo = SystemShortcut.WIDGETS.getShortcut(mLauncher, itemInfo);
              View widgetsView = null;
              int count = mSystemShortcutContainer.getChildCount();
              for (int i = 0; i < count; i++) {
                  View systemShortcutView = mSystemShortcutContainer.getChildAt(i);
                  if (systemShortcutView.getTag() instanceof SystemShortcut.Widgets) {
                      widgetsView = systemShortcutView;
                      break;
                  }
              }
  
              if (widgetInfo != null && widgetsView == null) {
                  // We didn't have any widgets cached but now there are some, so enable the shortcut.
                  if (mSystemShortcutContainer != PopupContainerWithArrow.this) {
                      initializeSystemShortcut(R.layout.system_shortcut_icon_only,
                              mSystemShortcutContainer, widgetInfo);
                  } //else {
  //====修改start==== 将else处理注释掉，否则在某些系统APP长按时会有循环闪烁动画
                      // If using the expanded system shortcut (as opposed to just the icon), we need
                      // to reopen the container to ensure measurements etc. all work out. While this
                      // could be quite janky, in practice the user would typically see a small
                      // flicker as the animation restarts partway through, and this is a very rare
                      // edge case anyway.
  //                    close(false);
  //                    PopupContainerWithArrow.showForIcon(mOriginalIcon);
  //                }
  //====修改end====
              } else if (widgetInfo == null && widgetsView != null) {
                  // No widgets exist, but we previously added the shortcut so remove it.
                  if (mSystemShortcutContainer != PopupContainerWithArrow.this) {
                      mSystemShortcutContainer.removeView(widgetsView);
                  } else {
                      close(false);
                      PopupContainerWithArrow.showForIcon(mOriginalIcon);
                  }
              }
          }
  
          // ... //
  
  }
  

• 移除拖动icon时顶部的卸载布局及边界框

  Workspace.java

  @Override
      public void onDragStart(DragObject dragObject, DragOptions options) {
          // ... //
          if (addNewPage) {
              mDeferRemoveExtraEmptyScreen = false;
              addExtraEmptyScreenOnDrag();
  
              if (dragObject.dragInfo.itemType == LauncherSettings.Favorites.ITEM_TYPE_APPWIDGET
                      && dragObject.dragSource != this) {
                  // When dragging a widget from different source, move to a page which has
                  // enough space to place this widget (after rearranging/resizing). We special case
                  // widgets as they cannot be placed inside a folder.
                  // Start at the current page and search right (on LTR) until finding a page with
                  // enough space. Since an empty screen is the furthest right, a page must be found.
                  int currentPage = getPageNearestToCenterOfScreen();
                  for (int pageIndex = currentPage; pageIndex < getPageCount(); pageIndex++) {
                      CellLayout page = (CellLayout) getPageAt(pageIndex);
                      if (page.hasReorderSolution(dragObject.dragInfo)) {
                          setCurrentPage(pageIndex);
                          break;
                      }
                  }
              }
          }
  
          // Always enter the spring loaded mode
  //====修改==== 注释掉这一行即可移除长按出现的卸载布局及边界框
  //        mLauncher.getStateManager().goToState(SPRING_LOADED);
          mStatsLogManager.logger().withItemInfo(dragObject.dragInfo)
                  .withInstanceId(dragObject.logInstanceId)
                  .log(LauncherEvent.LAUNCHER_ITEM_DRAG_STARTED);
      }
  

• 不显示顶部的“卸载、移除”

  Launcher.java

  protected void setupViews() {
          mDragLayer = findViewById(R.id.drag_layer);
          mFocusHandler = mDragLayer.getFocusIndicatorHelper();
          mWorkspace = mDragLayer.findViewById(R.id.workspace);
          mWorkspace.initParentViews(mDragLayer);
          mOverviewPanel = findViewById(R.id.overview_panel);
          mHotseat = findViewById(R.id.hotseat);
          mHotseat.setWorkspace(mWorkspace);
  
          // Setup the drag layer
          mDragLayer.setup(mDragController, mWorkspace);
  
          mWorkspace.setup(mDragController);
          // Until the workspace is bound, ensure that we keep the wallpaper offset locked to the
          // default state, otherwise we will update to the wrong offsets in RTL
          mWorkspace.lockWallpaperToDefaultPage();
          mWorkspace.bindAndInitFirstWorkspaceScreen(null /* recycled qsb */);
          mDragController.addDragListener(mWorkspace);
  
          // Get the search/delete/uninstall bar
          mDropTargetBar = mDragLayer.findViewById(R.id.drop_target_bar);
  
          // Setup Apps
          mAppsView = findViewById(R.id.apps_view);
  
          // Setup Scrim
          mScrimView = findViewById(R.id.scrim_view);
  
          // Setup the drag controller (drop targets have to be added in reverse order in priority)
  //====修改==== 这里注释掉顶部卸载栏的初始化及监听，则长按不会显示卸载、移除按钮
  //        mDropTargetBar.setup(mDragController);
  
          mAllAppsController.setupViews(mAppsView, mScrimView);
      }
  

4. 结语

以上为将系统初始的双层屏改为单层涉及到的全部改动，供参考。