在Android ActivityInstrumentationTestCase2中模拟一个投掷动作

好的,这是一个非常古老的问题,但是发布一个对我有用的解决方案,可能会帮助其他来寻找这个问题的人

int[] xy = new int[2];
View v = currentActivity.getCurrentFocus();
v.getLocationOnScreen(xy);
final int viewWidth = v.getWidth();
final int viewHeight = v.getHeight();
final float x = xy[0] + (viewWidth / 2.0f);
float fromY = xy[1] + (viewHeight / 2.0f);
int screenWidth = currentActivity.getWindowManager().getDefaultDisplay().getWidth();    
//Drag from centre of screen to Leftmost edge of display
TouchUtils.drag(this, (screenWidth - 1), x,  fromY, fromY , 5); //Vary the last parameter to sdjust speed of fling

从TouchUtils源来看,这里的问题是步骤计数只是要生成的触摸事件的数量,并不影响它们发生的速度:

    for (int i = 0; i < stepCount; ++i) {
        y += yStep;
        x += xStep;
        eventTime = SystemClock.uptimeMillis();
        event = MotionEvent.obtain(downTime, eventTime, MotionEvent.ACTION_MOVE, x, y, 0);
        inst.sendPointerSync(event);
        inst.waitForIdleSync();
    }

它在每次活动后都在等待与应用程序同步,所以它似乎没有足够快的速度来启动。我们可以从手势检测器识别玩偶的方式看出:

           // A fling must travel the minimum tap distance
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000);
            final float velocityY = velocityTracker.getYVelocity();
            final float velocityX = velocityTracker.getXVelocity();

            if ((Math.abs(velocityY) > ViewConfiguration.getMinimumFlingVelocity())
                    || (Math.abs(velocityX) > ViewConfiguration.getMinimumFlingVelocity())){
                handled = mListener.onFling(mCurrentDownEvent, mCurrentUpEvent, velocityX, velocityY);
            }

因此,我推荐一种定制的拖动方法,它不需要等待每次触摸移动事件的同步(不管怎样,我们不在乎每次拖动都会更新UI,我们只想生成一个fling)。类似这样(未经测试):

public static void fling(InstrumentationTestCase test, float fromX, float toX, float fromY,
        float toY, int stepCount) {
    Instrumentation inst = test.getInstrumentation();

    long downTime = SystemClock.uptimeMillis();
    long eventTime = SystemClock.uptimeMillis();

    float y = fromY;
    float x = fromX;

    float yStep = (toY - fromY) / stepCount;
    float xStep = (toX - fromX) / stepCount;

    MotionEvent event = MotionEvent.obtain(downTime, eventTime,
            MotionEvent.ACTION_DOWN, fromX, y, 0);
    inst.sendPointerSync(event);
    inst.waitForIdleSync();

    for (int i = 0; i < stepCount; ++i) {
        y += yStep;
        x += xStep;
        eventTime = SystemClock.uptimeMillis();
        event = MotionEvent.obtain(downTime, eventTime, MotionEvent.ACTION_MOVE, x, y, 0);
        inst.sendPointerSync(event);
        //inst.waitForIdleSync();
    }

    eventTime = SystemClock.uptimeMillis();
    event = MotionEvent.obtain(downTime, eventTime, MotionEvent.ACTION_UP, fromX, y, 0);
    inst.sendPointerSync(event);
    inst.waitForIdleSync();
}

实际上,我所做的只是在运动事件循环中注释掉等待空闲同步。为行驶距离和步数选择一些合理的值,这应该是可行的。如果没有,你可能需要在循环中等待一段时间,以便在事件发生得太快时稍微留出一些空间。

不确定这是否是您想要的,但下面是我编写的一个测试示例,以确保fling手势在自定义gallery组件上工作。

public void testLeftSwipe() {
    int initialSelectedItemPosition = mGallery.getSelectedItemPosition();

    Rect r = new Rect();
    mGallery.getGlobalVisibleRect(r);

    float fromX = r.centerX();
    float toX = r.centerX() - (r.width() / 4);
    float fromY = r.centerY();
    float toY = r.centerY();
    int stepCount = 10;

    TouchUtils.drag(this, fromX, toX, fromY, toY, stepCount);

    assertTrue(mGallery.getSelectedItemPosition() > initialSelectedItemPosition);
}