java - 用于压缩文件的 uidevice takescreenshot 选项不起作用

Question

我正在使用 UI Automator 在 Junit 测试中使用以下命令截取低分辨率屏幕截图。所有四个屏幕截图的大小相同。我希望它被压缩。让我知道是否有其他人能够成功实现它。我只想获得屏幕的缩略图，而不是高分辨率的屏幕截图。如果可用，建议替代方法。

getUiDevice().takeScreenshot(new File("/sdcard/Pictures/"+"test1.png"));
getUiDevice().takeScreenshot(new File("/sdcard/Pictures/"+"test2.png"),0.1f,10);
getUiDevice().takeScreenshot(new File("/sdcard/Pictures/"+"test3.png"),0.2f,20);
getUiDevice().takeScreenshot(new File("/sdcard/Pictures/"+"test4.png"),1.0f,20);

UI Automator API 的 Android 引用

TakeScreenshot

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

Parameters storePath File: where the PNG should be written to scale float: scale the screenshot down if needed; 1.0f for original size quality int: quality of the PNG compression; range: 0-100

Answer 1

这是UiDevice.java中takeScreenshot的实现:

/**
 * Take a screenshot of current window and store it as PNG
 *
 * The screenshot is adjusted per screen rotation
 *
 * @param storePath where the PNG should be written to
 * @param scale scale the screenshot down if needed; 1.0f for original size
 * @param quality quality of the PNG compression; range: 0-100
 * @return true if screen shot is created successfully, false otherwise
 * @since API Level 17
 */
public boolean takeScreenshot(File storePath, float scale, int quality) {
    Tracer.trace(storePath, scale, quality);
    return getAutomatorBridge().takeScreenshot(storePath, quality);
}

如您所见，scale 根本没有使用，quality 仅用于设置保存的 PNG 的质量。