校验结果
　　Ui Automator 是基于InstrumentationTestCase，同样InstrumentationTestCase是基于标准的JUnit Assert，那么我们也可以使用标准的JUnit Assert来判断结果。
　　下面代码片段演示一个计算器的代码，以及验证结果。
private static final String CALC_PACKAGE = "com.myexample.calc";
public void testTwoPlusThreeEqualsFive() {
// Enter an equation: 2 + 3 = ?
mDevice.findObject(new UiSelector()
.packageName(CALC_PACKAGE).resourceId("two")).click();
mDevice.findObject(new UiSelector()
.packageName(CALC_PACKAGE).resourceId("plus")).click();
mDevice.findObject(new UiSelector()
.packageName(CALC_PACKAGE).resourceId("three")).click();
mDevice.findObject(new UiSelector()
.packageName(CALC_PACKAGE).resourceId("equals")).click();
// Verify the result = 5
UiObject result = mDevice.findObject(By.res(CALC_PACKAGE， "result"));
assertEquals("5"， result.getText());
}
　　Api
　　UiDevice
void    clearLastTraversedText()
// Clears the text from the last UI traversal event.
// 清楚上次UI遍历的事件？
boolean click(int x， int y)
// Perform a click at arbitrary coordinates specified by the user
// 根据坐标点击
boolean drag(int startX， int startY， int endX， int endY， int steps)
// Performs a swipe from one coordinate to another coordinate.
// 拖动
void    dumpWindowHierarchy(File dest)
// Dump the current window hierarchy to a File.
// dump当前的层次化结构到文件中
void    dumpWindowHierarchy(OutputStream out)
// Dump the current window hierarchy to an OutputStream.
// dump当前的层次化结构到流中
void    dumpWindowHierarchy(String fileName)
// This method is deprecated. Use dumpWindowHierarchy(File) or dumpWindowHierarchy(OutputStream) instead.
// dump当前的层次化结构到文件中
UiObject2   findObject(BySelector selector)
// Returns the first object to match the selector criteria.
// 根据BySelector查找
UiObject    findObject(UiSelector selector)
// Returns a UiObject which represents a view that matches the specified selector criteria.
// 根据UiSelector 查找
List<UiObject2> findObjects(BySelector selector)
// Returns all objects that match the selector criteria.
// 根据BySelector查找
void    freezeRotation()
// Disables the sensors and freezes the device rotation at its current rotation state.
// 冻结旋转的状态
String  getCurrentActivityName()
// This method is deprecated. The results returned should be considered unreliable
// 获取当前Activity的名字，已经被废弃
String  getCurrentPackageName()
// Retrieves the name of the last package to report accessibility events.
// 获取当前package
int getDisplayHeight()
// Gets the height of the display， in pixels.
int getDisplayRotation()
// Returns the current rotation of the display， as defined in Surface
Point   getDisplaySizeDp()
// Returns the display size in dp (device-independent pixel) The returned display size is adjusted per screen rotation.
int getDisplayWidth()
// Gets the width of the display， in pixels.
static UiDevice getInstance()
// This method is deprecated. Should use getInstance(Instrumentation) instead. This version hides UiDevice's dependency on having an Instrumentation reference and is prone to misuse.
// 获取一个对象
static UiDevice getInstance(Instrumentation instrumentation)
// Retrieves a singleton instance of UiDevice
String  getLastTraversedText()
// Retrieves the text from the last UI traversal event received.
// 获取上一次遍历的文本
String  getLauncherPackageName()
// Retrieves default launcher package name
// 获取运行的packagename
String  getProductName()
// Retrieves the product name of the device.
boolean hasAnyWatcherTriggered()
// Checks if any registered UiWatcher have triggered.
// 检查是否有触发器触发
boolean hasObject(BySelector selector)
// Returns whether there is a match for the given selector criteria.
// 是否有符合的条件的
boolean hasWatcherTriggered(String watcherName)
// Checks if a specific registered UiWatcher has triggered.
boolean isNaturalOrientation()
// Check if the device is in its natural orientation.
boolean isScreenOn()
// Checks the power manager if the screen is ON.
boolean openNotification()
// Opens the notification shade.
// 打开通知
boolean openQuickSettings()
// Opens the Quick Settings shade.
// 打开设置
<R> R   performActionAndWait(Runnable action， EventCondition<R> condition， long timeout)
// Performs the provided action and waits for the condition to be met.
boolean pressBack()
// Simulates a short press on the BACK button.
boolean pressDPadCenter()
// Simulates a short press on the CENTER button.
boolean pressDPadDown()
// Simulates a short press on the DOWN button.
boolean pressDPadLeft()
// Simulates a short press on the LEFT button.
boolean pressDPadRight()
// Simulates a short press on the RIGHT button.
boolean pressDPadUp()
// Simulates a short press on the UP button.
boolean pressDelete()
// Simulates a short press on the DELETE key.
boolean pressEnter()
// Simulates a short press on the ENTER key.
boolean pressHome()
// Simulates a short press on the HOME button.
boolean pressKeyCode(int keyCode)
// Simulates a short press using a key code.
boolean pressKeyCode(int keyCode， int metaState)
// Simulates a short press using a key code.
boolean pressMenu()
// Simulates a short press on the MENU button.
boolean pressRecentApps()
// Simulates a short press on the Recent Apps button.
boolean pressSearch()
// Simulates a short press on the SEARCH button.
void    registerWatcher(String name， UiWatcher watcher)
// Registers a UiWatcher to run automatically when the testing framework is unable to find a match using a UiSelector.
void    removeWatcher(String name)
// Removes a previously registered UiWatcher.
void    resetWatcherTriggers()
// Resets a UiWatcher that has been triggered.
void    runWatchers()
// This method forces all registered watchers to run.
void    setCompressedLayoutHeirarchy(boolean compressed)
// Enables or disables layout hierarchy compression.
void    setOrientationLeft()
// Simulates orienting the device to the left and also freezes rotation by disabling the sensors.
// 设置旋转方向
void    setOrientationNatural()
// Simulates orienting the device into its natural orientation and also freezes rotation by disabling the sensors.
void    setOrientationRight()
// Simulates orienting the device to the right and also freezes rotation by disabling the sensors.
void    sleep()
// This method simply presses the power button if the screen is ON else it does nothing if the screen is already OFF.
// 关闭屏幕
boolean swipe(int startX， int startY， int endX， int endY， int steps)
// Performs a swipe from one coordinate to another using the number of steps to determine smoothness and speed.
boolean swipe(Point[] segments， int segmentSteps)
// Performs a swipe between points in the Point array.
boolean takeScreenshot(File storePath， float scale， int quality)
// Take a screenshot of current window and store it as PNG The screenshot is adjusted per screen rotation
// 截屏
boolean takeScreenshot(File storePath)
// Take a screenshot of current window and store it as PNG Default scale of 1.0f (original size) and 90% quality is used The screenshot is adjusted per screen rotation
void    unfreezeRotation()
// Re-enables the sensors and un-freezes the device rotation allowing its contents to rotate with the device physical rotation.
<R> R   wait(SearchCondition<R> condition， long timeout)
// Waits for given the condition to be met.
void    waitForIdle(long timeout)
// Waits for the current application to idle.
void    waitForIdle()
// Waits for the current application to idle.
boolean waitForWindowUpdate(String packageName， long timeout)
// Waits for a window content update event to occur.
void    wakeUp()
// This method simulates pressing the power button if the screen is OFF else it does nothing if the screen is already ON.
// 点亮屏幕
　　UiObject
void    clearTextField()
// Clears the existing text contents in an editable field.
// 清空输入接口
boolean click()
// Performs a click at the center of the visible bounds of the UI element represented by this UiObject.
// 点击
boolean clickAndWaitForNewWindow()
// Waits for window transitions that would typically take longer than the usual default timeouts.
// 点击并等待新界面
boolean clickAndWaitForNewWindow(long timeout)
// Performs a click at the center of the visible bounds of the UI element represented by this UiObject and waits for window transitions.
// 点击并等待新界面，设置等待时间
boolean clickBottomRight()
// Clicks the bottom and right corner of the UI element
// 点击右下边
boolean clickTopLeft()
// Clicks the top and left corner of the UI element
boolean dragTo(UiObject destObj， int steps)
// Drags this object to a destination UiObject.
// 拖动
boolean dragTo(int destX， int destY， int steps)
// Drags this object to arbitrary coordinates.
boolean exists()
// Check if view exists.
// 判断是否存在
Rect    getBounds()
// Returns the view's bounds property.
// 返回边界
UiObject    getChild(UiSelector selector)
// Creates a new UiObject for a child view that is under the present UiObject.
// 根据条件获取子元素
int getChildCount()
// Counts the child views immediately under the present UiObject.
// 获取子元素数量
String  getClassName()
// Retrieves the className property of the UI element.
// 获取当前元素的class name
String  getContentDescription()
// Reads the content_desc property of the UI element
UiObject    getFromParent(UiSelector selector)
// Creates a new UiObject for a sibling view or a child of the sibling view， relative to the present UiObject.
String  getPackageName()
// Reads the view's package property
final UiSelector    getSelector()
// Debugging helper.
String  getText()
// Reads the text property of the UI element
Rect    getVisibleBounds()
// Returns the visible bounds of the view.
// 获取可见边界
boolean isCheckable()
// Checks if the UI element's checkable property is currently true.
// 是否可以点击
boolean isChecked()
// Check if the UI element's checked property is currently true
// 是否已经选中
boolean isClickable()
// Checks if the UI element's clickable property is currently true.
boolean isEnabled()
// Checks if the UI element's enabled property is currently true.
boolean isFocusable()
// Check if the UI element's focusable property is currently true.
boolean isFocused()
// Check if the UI element's focused property is currently true
boolean isLongClickable()
// Check if the view's long-clickable property is currently true
boolean isScrollable()
// Check if the view's scrollable property is currently true
boolean isSelected()
// Checks if the UI element's selected property is currently true.
boolean longClick()
// Long clicks the center of the visible bounds of the UI element
// 长按
boolean longClickBottomRight()
// Long clicks bottom and right corner of the UI element
boolean longClickTopLeft()
// Long clicks on the top and left corner of the UI element
boolean performMultiPointerGesture(PointerCoords... touches)
// Performs a multi-touch gesture.
boolean performTwoPointerGesture(Point startPoint1， Point startPoint2， Point endPoint1， Point endPoint2， int steps)
// Generates a two-pointer gesture with arbitrary starting and ending points.
boolean pinchIn(int percent， int steps)
// Performs a two-pointer gesture， where each pointer moves diagonally toward the other， from the edges to the center of this UiObject .
boolean pinchOut(int percent， int steps)
// Performs a two-pointer gesture， where each pointer moves diagonally opposite across the other， from the center out towards the edges of the this UiObject.
boolean setText(String text)
// Sets the text in an editable field， after clearing the field's content.
// 设置输入内容
boolean swipeDown(int steps)
// Performs the swipe down action on the UiObject.
boolean swipeLeft(int steps)
// Performs the swipe left action on the UiObject.
boolean swipeRight(int steps)
// Performs the swipe right action on the UiObject.
boolean swipeUp(int steps)
// Performs the swipe up action on the UiObject.
boolean waitForExists(long timeout)
// Waits a specified length of time for a view to become visible.
boolean waitUntilGone(long timeout)
// Waits a specified length of time for a view to become undetectable.
　　总结
　　优点：
　　* 可以对所有操作进行自动化，操作简单
　　* 不需要对被测程序进行重签名，且，可以测试所有设备上的程序，比如~某APP，比如~拨号，比如~发信息等等
　　* 对于控件定位，要比robotium简单一点点
　　缺点：
　　* Ui Automator需要android level 16以上才可以使用，因为在level 16及以上的API里面才带有uiautomator工具
　　* 如果想要使用resource-id定位控件，则需要level 18及以上才可以
　　* 对中文支持不好（不代表不支持，第三方jar可以实现）