uiautomator 获取控件，点击的原理

首先，找控件然后点击：

new UiObject（By.selector（“test”））.click（）;

第一步：调用getQueryController

this.getQueryController().findAccessibilityNodeInfo(this.mUiSelector);

第二步：获取getRootInActiveWindow，三层调用，最后通过mUiAutomation获取

AccessibilityNodeInfo rootNode = this.getRootNode();

this.mUiAutomatorBridge.getRootInActiveWindow();

this.mUiAutomation.getRootInActiveWindow();

第三步：selector和rootNode算法对比找到所需要的object

this.translateCompoundSelector(uiSelector, rootNode, isCounting);

第四步：object click

public boolean click() throws UiObjectNotFoundException {
    Tracer.trace(new Object[0]);
    AccessibilityNodeInfo node = this.findAccessibilityNodeInfo(this.mConfig.getWaitForSelectorTimeout());
    if(node == null) {
        throw new UiObjectNotFoundException(this.mUiSelector.toString());
    } else {
        Rect rect = this.getVisibleBounds(node);
        return this.getInteractionController().clickAndSync(rect.centerX(), rect.centerY(), this.mConfig.getActionAcknowledgmentTimeout());
    }
}

第五步:调用InteractionController

private Runnable clickRunnable(final int x, final int y) {
    return new Runnable() {
        public void run() {
            if(InteractionController.this.touchDown(x, y)) {
                SystemClock.sleep(100L);
                InteractionController.this.touchUp(x, y);
            }

        }
    };
}

第六步：转换成event，最后还是uiautomation 注入事件

private boolean touchUp(int x, int y) {
    if(DEBUG) {
        Log.d(LOG_TAG, "touchUp (" + x + ", " + y + ")");
    }

    long eventTime = SystemClock.uptimeMillis();
    MotionEvent event = MotionEvent.obtain(this.mDownTime, eventTime, 1, (float)x, (float)y, 0);
    event.setSource(4098);
    this.mDownTime = 0L;
    return this.injectEventSync(event);
}

private boolean injectEventSync(InputEvent event) {
    return this.mUiAutomatorBridge.injectInputEvent(event, true);
}

public boolean injectInputEvent(InputEvent event, boolean sync) {
    return this.mUiAutomation.injectInputEvent(event, sync);
}