io.appium.java_client

Class ScreenshotState

java.lang.Object

io.appium.java_client.ScreenshotState

public class ScreenshotState
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ScreenshotState.ScreenshotComparisonError
static class	ScreenshotState.ScreenshotComparisonTimeout

Constructor Summary

Constructors

Constructor and Description
ScreenshotState(ComparesImages comparator)
ScreenshotState(ComparesImages comparator, java.util.function.Supplier<java.awt.image.BufferedImage> stateProvider) The class constructor accepts two arguments.

Method Summary

Modifier and Type	Method and Description
java.time.Duration	getComparisonInterval() Gets the interval value in ms between similarity verification rounds in verify* methods.
double	getOverlapScore(java.awt.image.BufferedImage refImage, java.awt.image.BufferedImage tplImage) Compares two valid java bitmaps and calculates similarity score between them.
ScreenshotState	remember() Call this method to save the initial screenshot state.
ScreenshotState	remember(java.awt.image.BufferedImage customInitialState) This method allows to pass a custom bitmap for further comparison instead of taking one using screenshot provider function.
ScreenshotState	setComparisonInterval(java.time.Duration comparisonInterval) Sets the interval between similarity verification rounds in verify* methods.
ScreenshotState	verifyChanged(java.time.Duration timeout, double minScore) Verifies whether the state of the screenshot provided by stateProvider lambda function is changed within the given timeout.
ScreenshotState	verifyNotChanged(java.time.Duration timeout, double minScore) Verifies whether the state of the screenshot provided by stateProvider lambda function is not changed within the given timeout.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ScreenshotState

public ScreenshotState(ComparesImages comparator,
                       java.util.function.Supplier<java.awt.image.BufferedImage> stateProvider)

The class constructor accepts two arguments. The first one is image comparator, the second parameter is lambda function, that provides the screenshot of the necessary screen area to be verified for similarity. This lambda method is NOT called upon class creation. One has to invoke remember() method in order to call it.

Examples of provider function with Appium driver: () -> { final byte[] srcImage = ((TakesScreenshot) driver).getScreenshotAs(OutputType.BYTES); return ImageIO.read(new ByteArrayInputStream(srcImage)); } or () -> { final byte[] srcImage = ((TakesScreenshot) driver).getScreenshotAs(OutputType.BYTES); final BufferedImage screenshot = ImageIO.read(new ByteArrayInputStream(srcImage)); final WebElement element = driver.findElement(locator); // Can be simplified in Selenium 3.0+ by using getRect method of WebElement interface final Point elementLocation = element.getLocation(); final Dimension elementSize = element.getSize(); return screenshot.getSubimage( new Rectangle(elementLocation.x, elementLocation.y, elementSize.width, elementSize.height); }

Parameters:

comparator - image comparator

stateProvider - lambda function, which returns a screenshot for further comparison

ScreenshotState

public ScreenshotState(ComparesImages comparator)

Method Detail

getComparisonInterval

public java.time.Duration getComparisonInterval()

Gets the interval value in ms between similarity verification rounds in verify* methods.

Returns:

current interval value in ms

setComparisonInterval

public ScreenshotState setComparisonInterval(java.time.Duration comparisonInterval)

Sets the interval between similarity verification rounds in verify* methods.

Parameters:

comparisonInterval - interval value. 500 ms by default

Returns:

self instance for chaining

remember

public ScreenshotState remember()

Call this method to save the initial screenshot state. It is mandatory to call before any verify* method is invoked.

Returns:

self instance for chaining

remember

public ScreenshotState remember(java.awt.image.BufferedImage customInitialState)

This method allows to pass a custom bitmap for further comparison instead of taking one using screenshot provider function. This might be useful in some advanced cases.

Parameters:

customInitialState - valid bitmap

Returns:

self instance for chaining

verifyChanged

public ScreenshotState verifyChanged(java.time.Duration timeout,
                                     double minScore)

Verifies whether the state of the screenshot provided by stateProvider lambda function is changed within the given timeout.

Parameters:

timeout - timeout value

minScore - the value in range (0.0, 1.0)

Returns:

self instance for chaining

Throws:

ScreenshotState.ScreenshotComparisonTimeout - if the calculated score is still greater or equal to the given score after timeout happens

ScreenshotState.ScreenshotComparisonError - if remember() method has not been invoked yet

verifyNotChanged

public ScreenshotState verifyNotChanged(java.time.Duration timeout,
                                        double minScore)

Verifies whether the state of the screenshot provided by stateProvider lambda function is not changed within the given timeout.

Parameters:

timeout - timeout value

minScore - the value in range (0.0, 1.0)

Returns:

self instance for chaining

Throws:

ScreenshotState.ScreenshotComparisonTimeout - if the calculated score is still less than the given score after timeout happens

ScreenshotState.ScreenshotComparisonError - if remember() method has not been invoked yet

getOverlapScore

public double getOverlapScore(java.awt.image.BufferedImage refImage,
                              java.awt.image.BufferedImage tplImage)

Compares two valid java bitmaps and calculates similarity score between them. Both images are expected to be of the same size/resolution. The method implicitly invokes ComparesImages.getImagesSimilarity(byte[], byte[]).

Parameters:

refImage - reference image

tplImage - template

Returns:

similarity score value in range (-1.0, 1.0]. 1.0 is returned if the images are equal

Throws:

ScreenshotState.ScreenshotComparisonError - if provided images are not valid or have different resolution