android - 有没有办法以编程方式将滚动视图滚动到特定的编辑文本？

Question

我有一个很长的滚动视图活动。这是一个包含用户必须填写的各种字段的表单。我在表单的中间有一个复选框，当用户检查它时，我想滚动到视图的特定部分。有没有办法以编程方式滚动到 EditText 对象（或任何其他视图对象）？

另外，我知道这可以使用 X 和 Y 坐标，但我想避免这样做，因为表单可能会因用户而异。

score 502 · Accepted Answer

private final void focusOnView(){
        your_scrollview.post(new Runnable() {
            @Override
            public void run() {
                your_scrollview.scrollTo(0, your_EditBox.getBottom());
            }
        });
    }

score 61 · Accepted Answer

如果您想将视图滚动到滚动视图的中心， Sherif elKhatib 的答案可以大大提高。这种可重用的方法将视图平滑滚动到 HorizontalScrollView 的可见中心。

private final void focusOnView(final HorizontalScrollView scroll, final View view) {
    new Handler().post(new Runnable() {
        @Override
        public void run() {
            int vLeft = view.getLeft();
            int vRight = view.getRight();
            int sWidth = scroll.getWidth();
            scroll.smoothScrollTo(((vLeft + vRight - sWidth) / 2), 0);
        }
    });
}

垂直ScrollView使用

...
int vTop = view.getTop();
int vBottom = view.getBottom();
int sHeight = scroll.getBottom();
scroll.smoothScrollTo(((vTop + vBottom - sHeight) / 2), 0);
...

score 57 · Accepted Answer

这对我很有效：

  targetView.getParent().requestChildFocus(targetView,targetView);

public void RequestChildFocus（查看孩子，查看重点）

child - 此 ViewParent 需要焦点的孩子。此视图将包含焦点视图。实际关注的不一定是视图。

聚焦- 实际具有焦点的孩子的后代视图

score 40 · Accepted Answer

在我看来，滚动到给定矩形的最佳方式是通过View.requestRectangleOnScreen(Rect, Boolean). 您应该在要滚动到的位置上调用它View并传递要在屏幕上可见的本地矩形。第二个参数应该false用于平滑滚动和true立即滚动。

final Rect rect = new Rect(0, 0, view.getWidth(), view.getHeight());
view.requestRectangleOnScreen(rect, false);

score 12 · Accepted Answer

我根据 WarrenFaith 的 Answer 制作了一个小型实用方法，此代码还考虑了该视图是否已经在滚动视图中可见，无需滚动。

public static void scrollToView(final ScrollView scrollView, final View view) {

    // View needs a focus
    view.requestFocus();

    // Determine if scroll needs to happen
    final Rect scrollBounds = new Rect();
    scrollView.getHitRect(scrollBounds);
    if (!view.getLocalVisibleRect(scrollBounds)) {
        new Handler().post(new Runnable() {
            @Override
            public void run() {
                scrollView.smoothScrollTo(0, view.getBottom());
            }
        });
    } 
}

score 11 · Accepted Answer

11

您应该将您的TextView请求重点放在：

    mTextView.requestFocus();

于 2011-07-26T14:49:12.760 回答

score 8 · Accepted Answer

我的 EditText 在我的 ScrollView 中嵌套了几层，它本身不是布局的根视图。因为 getTop() 和 getBottom() 似乎报告了它包含的视图中的坐标，所以我让它通过遍历 EditText 的父级来计算从 ScrollView 顶部到 EditText 顶部的距离。

// Scroll the view so that the touched editText is near the top of the scroll view
new Thread(new Runnable()
{
    @Override
    public
    void run ()
    {
        // Make it feel like a two step process
        Utils.sleep(333);

        // Determine where to set the scroll-to to by measuring the distance from the top of the scroll view
        // to the control to focus on by summing the "top" position of each view in the hierarchy.
        int yDistanceToControlsView = 0;
        View parentView = (View) m_editTextControl.getParent();
        while (true)
        {
            if (parentView.equals(scrollView))
            {
                break;
            }
            yDistanceToControlsView += parentView.getTop();
            parentView = (View) parentView.getParent();
        }

        // Compute the final position value for the top and bottom of the control in the scroll view.
        final int topInScrollView = yDistanceToControlsView + m_editTextControl.getTop();
        final int bottomInScrollView = yDistanceToControlsView + m_editTextControl.getBottom();

        // Post the scroll action to happen on the scrollView with the UI thread.
        scrollView.post(new Runnable()
        {
            @Override
            public void run()
            {
                int height =m_editTextControl.getHeight();
                scrollView.smoothScrollTo(0, ((topInScrollView + bottomInScrollView) / 2) - height);
                m_editTextControl.requestFocus();
            }
        });
    }
}).start();

score 7 · Accepted Answer

另一种变化是：

scrollView.postDelayed(new Runnable()
{
    @Override
    public void run()
    {
        scrollView.smoothScrollTo(0, img_transparent.getTop());
    }
}, 200);

或者您可以使用该post()方法。

score 5 · Accepted Answer

如果 ScrollView 是 ChildView 的直接父级，则上述答案将正常工作。如果您的 ChildView 被包裹在 ScrollView 中的另一个 ViewGroup 中，则会导致意外行为，因为 View.getTop() 获取相对于其父级的位置。在这种情况下，您需要实现：

public static void scrollToInvalidInputView(ScrollView scrollView, View view) {
    int vTop = view.getTop();

    while (!(view.getParent() instanceof ScrollView)) {
        view = (View) view.getParent();
        vTop += view.getTop();
    }

    final int scrollPosition = vTop;

    new Handler().post(() -> scrollView.smoothScrollTo(0, scrollPosition));
}

score 5 · Accepted Answer

我知道这对于更好的答案可能为时已晚，但理想的完美解决方案必须是像定位器这样的系统。我的意思是，当系统为编辑器字段进行定位时，它会将字段放在键盘上，因此按照 UI/UX 规则，它是完美的。

下面的代码使Android方式定位顺利。首先，我们将当前滚动点作为参考点。第二件事是为编辑器找到最佳定位滚动点，为此我们滚动到顶部，然后请求编辑器字段使 ScrollView 组件进行最佳定位。嘎查！我们已经学会了最好的位置。现在，我们要做的是从上一个点平滑滚动到我们新找到的点。如果您愿意，您可以通过使用scrollTo而不是仅使用smoothScrollTo来省略平滑滚动。

注意：主容器 ScrollView 是一个名为 scrollViewSignup 的成员字段，因为我的示例是一个注册屏幕，您可能会想很多。

view.setOnFocusChangeListener(new View.OnFocusChangeListener() {
        @Override
        public void onFocusChange(final View view, boolean b) {
            if (b) {
                scrollViewSignup.post(new Runnable() {
                    @Override
                    public void run() {
                        int scrollY = scrollViewSignup.getScrollY();
                        scrollViewSignup.scrollTo(0, 0);
                        final Rect rect = new Rect(0, 0, view.getWidth(), view.getHeight());
                        view.requestRectangleOnScreen(rect, true);

                        int new_scrollY = scrollViewSignup.getScrollY();
                        scrollViewSignup.scrollTo(0, scrollY);
                        scrollViewSignup.smoothScrollTo(0, new_scrollY);
                    }
                });
            }
        }
    });

如果您想将此块用于所有EditText实例，并快速将其与您的屏幕代码集成。您可以简单地制作如下所示的遍历器。为此，我将主 OnFocusChangeListener 设为名为focusChangeListenerToScrollEditor的成员字段，并在 onCreate 期间调用它，如下所示。

traverseEditTextChildren(scrollViewSignup, focusChangeListenerToScrollEditor);

方法实现如下。

private void traverseEditTextChildren(ViewGroup viewGroup, View.OnFocusChangeListener focusChangeListenerToScrollEditor) {
    int childCount = viewGroup.getChildCount();
    for (int i = 0; i < childCount; i++) {
        View view = viewGroup.getChildAt(i);
        if (view instanceof EditText)
        {
            ((EditText) view).setOnFocusChangeListener(focusChangeListenerToScrollEditor);
        }
        else if (view instanceof ViewGroup)
        {
            traverseEditTextChildren((ViewGroup) view, focusChangeListenerToScrollEditor);
        }
    }
}

因此，我们在这里所做的就是让所有 EditText 实例子级调用焦点的侦听器。

为了达到这个解决方案，我在这里检查了所有的解决方案，并生成了一个新的解决方案以获得更好的 UI/UX 结果。

非常感谢所有其他激励我的答案。

score 4 · Accepted Answer

4

yourScrollView.smoothScrollTo(0, yourEditText.getTop());

去做就对了 ;）

于 2021-06-14T13:17:48.500 回答

score 3 · Accepted Answer

 scrollView.post(new Runnable() {
                    @Override
                    public void run() {
                        scrollView.smoothScrollTo(0, myTextView.getTop());

                    }
                });

从我的实际项目中回答。

score 2 · Accepted Answer

我想我找到了更优雅、更不容易出错的解决方案

ScrollView.requestChildRectangleOnScreen

不涉及数学，并且与其他建议的解决方案相反，它将正确处理上下滚动。

/**
 * Will scroll the {@code scrollView} to make {@code viewToScroll} visible
 * 
 * @param scrollView parent of {@code scrollableContent}
 * @param scrollableContent a child of {@code scrollView} whitch holds the scrollable content (fills the viewport).
 * @param viewToScroll a child of {@code scrollableContent} to whitch will scroll the the {@code scrollView}
 */
void scrollToView(ScrollView scrollView, ViewGroup scrollableContent, View viewToScroll) {
    Rect viewToScrollRect = new Rect(); //coordinates to scroll to
    viewToScroll.getHitRect(viewToScrollRect); //fills viewToScrollRect with coordinates of viewToScroll relative to its parent (LinearLayout) 
    scrollView.requestChildRectangleOnScreen(scrollableContent, viewToScrollRect, false); //ScrollView will make sure, the given viewToScrollRect is visible
}

将其包装起来postDelayed以使其更可靠是个好主意，以防ScrollView目前正在更改

/**
 * Will scroll the {@code scrollView} to make {@code viewToScroll} visible
 * 
 * @param scrollView parent of {@code scrollableContent}
 * @param scrollableContent a child of {@code scrollView} whitch holds the scrollable content (fills the viewport).
 * @param viewToScroll a child of {@code scrollableContent} to whitch will scroll the the {@code scrollView}
 */
private void scrollToView(final ScrollView scrollView, final ViewGroup scrollableContent, final View viewToScroll) {
    long delay = 100; //delay to let finish with possible modifications to ScrollView
    scrollView.postDelayed(new Runnable() {
        public void run() {
            Rect viewToScrollRect = new Rect(); //coordinates to scroll to
            viewToScroll.getHitRect(viewToScrollRect); //fills viewToScrollRect with coordinates of viewToScroll relative to its parent (LinearLayout) 
            scrollView.requestChildRectangleOnScreen(scrollableContent, viewToScrollRect, false); //ScrollView will make sure, the given viewToScrollRect is visible
        }
    }, delay);
}

score 1 · Accepted Answer

参考：https ://stackoverflow.com/a/6438240/2624806

以下效果要好得多。

mObservableScrollView.post(new Runnable() {
            public void run() { 
                mObservableScrollView.fullScroll([View_FOCUS][1]); 
            }
        });

score 1 · Accepted Answer

我的解决方案是：

            int[] spinnerLocation = {0,0};
            spinner.getLocationOnScreen(spinnerLocation);

            int[] scrollLocation = {0, 0};
            scrollView.getLocationInWindow(scrollLocation);

            int y = scrollView.getScrollY();

            scrollView.smoothScrollTo(0, y + spinnerLocation[1] - scrollLocation[1]);

score 1 · Accepted Answer

垂直滚动，适用于表单。答案基于 Ahmadalibaloch 水平滚动。

private final void focusOnView(final HorizontalScrollView scroll, final View view) {
    new Handler().post(new Runnable() {
        @Override
        public void run() {
            int top = view.getTop();
            int bottom = view.getBottom();
            int sHeight = scroll.getHeight();
            scroll.smoothScrollTo(0, ((top + bottom - sHeight) / 2));
        }
    });
}

score 1 · Accepted Answer

查看 Android 源代码，您会发现已经有一个成员函数ScrollView– scrollToChild(View)– 完全按照要求执行。不幸的是，这个功能被标记为一些晦涩的原因private。基于该函数，我编写了以下函数，该函数ScrollView在指定的参数上方找到第View一个并滚动它以使其在中可见ScrollView：

 private void make_visible(View view)
 {
  int vt = view.getTop();
  int vb = view.getBottom();

  View v = view;

  for(;;)
     {
      ViewParent vp = v.getParent();

      if(vp == null || !(vp instanceof ViewGroup))
         break;

      ViewGroup parent = (ViewGroup)vp;

      if(parent instanceof ScrollView)
        {
         ScrollView sv = (ScrollView)parent;

         // Code based on ScrollView.computeScrollDeltaToGetChildRectOnScreen(Rect rect) (Android v5.1.1):

         int height = sv.getHeight();
         int screenTop = sv.getScrollY();
         int screenBottom = screenTop + height;

         int fadingEdge = sv.getVerticalFadingEdgeLength();

         // leave room for top fading edge as long as rect isn't at very top
         if(vt > 0)
            screenTop += fadingEdge;

         // leave room for bottom fading edge as long as rect isn't at very bottom
         if(vb < sv.getChildAt(0).getHeight())
            screenBottom -= fadingEdge;

         int scrollYDelta = 0;

         if(vb > screenBottom && vt > screenTop) 
           {
            // need to move down to get it in view: move down just enough so
            // that the entire rectangle is in view (or at least the first
            // screen size chunk).

            if(vb-vt > height) // just enough to get screen size chunk on
               scrollYDelta += (vt - screenTop);
            else              // get entire rect at bottom of screen
               scrollYDelta += (vb - screenBottom);

             // make sure we aren't scrolling beyond the end of our content
            int bottom = sv.getChildAt(0).getBottom();
            int distanceToBottom = bottom - screenBottom;
            scrollYDelta = Math.min(scrollYDelta, distanceToBottom);
           }
         else if(vt < screenTop && vb < screenBottom) 
           {
            // need to move up to get it in view: move up just enough so that
            // entire rectangle is in view (or at least the first screen
            // size chunk of it).

            if(vb-vt > height)    // screen size chunk
               scrollYDelta -= (screenBottom - vb);
            else                  // entire rect at top
               scrollYDelta -= (screenTop - vt);

            // make sure we aren't scrolling any further than the top our content
            scrollYDelta = Math.max(scrollYDelta, -sv.getScrollY());
           }

         sv.smoothScrollBy(0, scrollYDelta);
         break;
        }

      // Transform coordinates to parent:
      int dy = parent.getTop()-parent.getScrollY();
      vt += dy;
      vb += dy;

      v = parent;
     }
 }

score 1 · Accepted Answer

你可以ObjectAnimator这样使用：

ObjectAnimator.ofInt(yourScrollView, "scrollY", yourView.getTop()).setDuration(1500).start();

score 0 · Accepted Answer

根据 Sherif 的回答，以下内容最适合我的用例。值得注意的变化是getTop()代替getBottom()和smoothScrollTo()代替scrollTo()。

    private void scrollToView(final View view){
        final ScrollView scrollView = findViewById(R.id.bookmarksScrollView);
        if(scrollView == null) return;

        scrollView.post(new Runnable() {
            @Override
            public void run() {
                scrollView.smoothScrollTo(0, view.getTop());
            }
        });
    }

score 0 · Accepted Answer

问：有没有办法以编程方式将滚动视图滚动到特定的编辑文本？

Ans：recyclerview 最后位置的嵌套滚动视图添加了记录数据。

adapter.notifyDataSetChanged();
nested_scroll.setScrollY(more Detail Recycler.getBottom());

有没有办法以编程方式将滚动视图滚动到特定的编辑文本？

score 0 · Accepted Answer

以下是我正在使用的：

int amountToScroll = viewToShow.getBottom() - scrollView.getHeight() + ((LinearLayout.LayoutParams) viewToShow.getLayoutParams()).bottomMargin;
// Check to see if scrolling is necessary to show the view
if (amountToScroll > 0){
    scrollView.smoothScrollTo(0, amountToScroll);
}

这将获得显示视图底部所需的滚动量，包括该视图底部的任何边距。

score 0 · Accepted Answer

就我而言，那不是EditText，那是googleMap。它像这样成功地工作。

    private final void focusCenterOnView(final ScrollView scroll, final View view) {
    new Handler().post(new Runnable() {
        @Override
        public void run() {
            int centreX=(int) (view.getX() + view.getWidth()  / 2);
            int centreY= (int) (view.getY() + view.getHeight() / 2);
            scrollView.smoothScrollBy(centreX, centreY);
        }
    });
}

score 0 · Accepted Answer

如果您想在打开软键盘时滚动到视图，那么它可能会有点棘手。到目前为止，我得到的最佳解决方案是结合使用插入回调和requestRectangleOnScreen方法。

首先，您需要设置插入回调：

fun View.doOnApplyWindowInsetsInRoot(block: (View, WindowInsetsCompat, Rect) -> Unit) {
    val initialPadding = recordInitialPaddingForView(this)
    val root = getRootForView(this)
    ViewCompat.setOnApplyWindowInsetsListener(root) { v, insets ->
        block(v, insets, initialPadding)
        insets
    }
    requestApplyInsetsWhenAttached()
}

fun View.requestApplyInsetsWhenAttached() {
    if (isAttachedToWindow) {
        requestApplyInsets()
    } else {
        addOnAttachStateChangeListener(object : View.OnAttachStateChangeListener {
            override fun onViewAttachedToWindow(v: View) {
                v.removeOnAttachStateChangeListener(this)
                v.requestApplyInsets()
            }

            override fun onViewDetachedFromWindow(v: View) = Unit
        })
    }
}

我们正在根视图上设置回调以确保我们被调用。Insets 可以在我们有问题的视图收到它们之前被消耗掉，所以我们必须在这里做额外的工作。

现在几乎很容易：

doOnApplyWindowInsetsInRoot { _, _, _ ->
    post {
        if (viewInQuestion.hasFocus()) {
            requestRectangleOnScreen(Rect(0, 0, width, height))
        }
    }
}

您可以摆脱焦点检查。它可以限制调用次数requestRectangleOnScreen。我使用post在可滚动父计划滚动到焦点视图后运行操作。

score 0 · Accepted Answer

如果有人正在寻找 Kotlin 版本，您可以使用扩展功能来做到这一点

fun ScrollView.scrollToChild(view: View, onScrolled: (() -> Unit)? = null) {
    view.requestFocus()
    val scrollBounds = Rect()
    getHitRect(scrollBounds)
    if (!view.getLocalVisibleRect(scrollBounds)) {
        findViewTreeLifecycleOwner()?.lifecycleScope?.launch(Dispatchers.Main) {
            smoothScrollTo(0, view.bottom - 40)
            onScrolled?.invoke()
        }
    }
}

有一个小回调可以让你在滚动后做一些事情。

score -1 · Accepted Answer

如果 scrlMain 是您的 NestedScrollView，则使用以下内容，

scrlMain.post(new Runnable() {
                    @Override
                    public void run() {
                        scrlMain.fullScroll(View.FOCUS_UP);

                    }
                });

android - 有没有办法以编程方式将滚动视图滚动到特定的编辑文本？

25 回答 25

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