tip of the day
With a single keystroke, you can apply another code style/coloring scheme or keymap right from the editor. Just press Ctrl+后引号 (View | Quick Switch Scheme), to specify the scheme you want to change Use Ctrl+Shift+Enter to complete a current statement such as if, do-while, try-catch, return (or a method call) into a syntactically correct construct (e.g. add curly braces). When in the Go to Class, Go to Symbol, or Go to File popup, you can ease the search by filtering the lookup list with the help of the "camel words" prefixes. Use Ctrl+Shift+I (View | Quick Definition), to quickly review definition or content of the symbol at caret, without the need to open it in a new editor tab. You can use Basic Completion (Ctrl+空格) in HTML, CSS and JavaScript files, for completing attributes, parameters, tags, selectors, etc. The Edit | Copy Reference action can be used to insert a reference to a field/method/class/file into the current position in the editor. For example, go to the java.util.Collections JDK class, place the cursor within the EMPTY-MAP field and press Ctrl+Alt+Shift+C: The Code | Move Statement Up/Down action is useful for reorganizing the code lines in your file, e.g., for bringing a variable declaration closer to variable usage. Select a code fragment and press Ctrl+Shift+向上箭头 or Ctrl+Shift+向下箭头. The following pictures show an initial location of a code fragment, and the results of moving the selected fragment up and down. By pressing Alt+Shift+F10 you can access the Run/Debug dropdown on the main toolbar, without the need to use your mouse. The Quick Definition Viewer (Ctrl+Shift+I) can also be used for items in lookup lists that appear on code completion and class/file/symbol navigaton commands. You can use Basic Completion (Ctrl+空格) within Java String literals and in other file types, for completing .properties keys. You can quickly view the image referenced at caret by using the Quick Definition (Ctrl+Shift+I). The underlying image will be opened in a popup instead of a separate editor tab. It is possible to rename CSS selectors directly from HTML. Position the caret at the selector to be renamed and press Shift+F6 (Refactor | Rename). Navigation bar is a quick alternative to the Project view. Use Alt+Home keyboard shortcut to show the navigation bar, and arrow keys to locate the necessary files or folders. The Changes tool window shows all deleted, modified, and unversioned files in a single view. Use Alt+9 keyboard shortcut to show or hide this tool window. From the Changes tool window you can perform all the necessary version control actions: commit changes, manage changelists, put resources under version control, examine differences and more. If you notice that Android Studio works slowly, consider the possibility to reduce the number of folders under antivirus protection. Each antivirus check in your project consumes resources. You can significantly improve the performance, if you exclude certain folders from the antivirus protection. You can quickly open a Maven project by selecting a pom.xml file in the File | Open dialog. The corresponding Maven project is imported with default settings, without launching the wizard. If you don't want to commit some of your changes to the repository, you can set them aside for a while, by moving to a separate changelist, or by putting them to a shelf. Select such file in the Local tab of the Changes tool window, and on the context menu choose Move to Another Changelist, or Shelve Changes. You can quickly open an Eclipse project by selecting a .classpath or .project file in the File | Open dialog. The corresponding Eclipse project is imported with default settings, without launching the wizard. You can bring forward the list of all usages of a class, method or variable across the whole project, and quickly jump to the selected usage. To do that, place the caret at the symbol's name or at its usage in code and press Ctrl+Alt+F7 (Edit | Find | Show Usages in the main menu), scroll the list and click the desired usage. To quickly find a menu command or toolbar action, you do not need to look through the menus. Just press Ctrl+Shift+A (Help | Find Action on the main menu) and start typing the name of the action. Choose the desired action from the suggestion list. To quickly find and run an inspection, press Ctrl+Alt+Shift+I and start typing the name of the inspection or its group. Choose the desired inspection from the suggestion list and then specify the desired scope. You can quickly find a setting you need in the Settings/Preferences dialog, without browsing through the numerous options. Just type some characters that, in your opinion, exist in the option description, and the list of settings will reduce to the matching ones. Select the desired entry, and see the setting that contains the entered characters highlighted: You can create code constructs using statement completion. Start typing a method declaration or a statement, and press Ctrl+Shift+Enter after the opening parenthesis. The braces are created, with the caret placed inside:
打开外部文件并编辑
（1）通过主菜单 File - Open File
（2）将外部文件拖到Android Studio编辑器中
打开最近打开过的文件
（1）通过主菜单 View - Recent Files
（2）快捷键 Command+E
打开最近更改过的文件
（1）通过主菜单 View - Recently Changed Files
（2）快捷键 Command+Shift+E
ctrl+tab实现项目文件的切换