在 subview 上调用 setVisibility(View.VISIBLE) 后，Android ScrollView 滚动到顶部

Question

我有一个 ScrollView用RelativeLayout在里面。这RelativeLayout然后有几个View在里面。这几个之一 View s 是 CheckBox .当 CheckBox已选中/未选中，其他一些 View s 应该相应地出现/消失。出现和消失工作正常，但每次目标 View s 出现或消失，ScrollView一直滚动到顶部，我不得不向下滚动以查看发生了什么。

我用来控制可见性的代码是:

public void crossCountryCheckboxClicked(View view)
{
    CheckBox crossCountryCheckBox = (CheckBox)findViewById(R.id.checkbox_cross_country);
    EditText crossCountryHoursTextBox = (EditText)findViewById(R.id.cross_country_hours);
    if (crossCountryCheckBox.isChecked())
    {
        crossCountryHoursTextBox.setVisibility(View.VISIBLE);
    }
    else
    {
        crossCountryHoursTextBox.setVisibility(View.GONE);
    }
}

和 crossCountryCheckboxClicked()通过指定 android:onClick 调用方法CheckBox 上的属性XML 布局文件中的元素。

这是 XML 布局文件:

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:custom="http://schemas.android.com/apk/res/logbook.app.activities"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <TextView
        android:id="@+id/flight_date"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

    <EditText
        android:id="@+id/aeroplane_type"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/flight_date"
        android:hint="@string/aeroplane_type" />

    <EditText
        android:id="@+id/aeroplane_registration"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/aeroplane_type"
        android:hint="@string/aeroplane_registration" />

    <EditText
        android:id="@+id/pilot_name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/aeroplane_registration"
        android:hint="@string/pilot_name" />

    <EditText
        android:id="@+id/copilot_name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/pilot_name"
        android:hint="@string/copilot_name" />

    <EditText
        android:id="@+id/from_aerodome"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/copilot_name"
        android:hint="@string/from_aerodome" />

    <EditText
        android:id="@+id/to_aerodome"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/copilot_name"
        android:layout_toRightOf="@id/from_aerodome"
        android:hint="@string/to_aerodome" />

    <EditText
        android:id="@+id/remarks"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/from_aerodome"
        android:hint="@string/remarks" />

    <Spinner
        android:id="@+id/aircraft_engine_type_spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/remarks" />

    <Spinner
        android:id="@+id/time_of_day_spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/aircraft_engine_type_spinner" />

    <Spinner
        android:id="@+id/pilot_role_spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/time_of_day_spinner" />

    <TextView
        android:id="@+id/on_time"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/pilot_role_spinner"
        android:hint="@string/on_time_hint" />

    <TextView
        android:id="@+id/takeoff_time"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/on_time"
        android:hint="@string/takeoff_time_hint" />

    <TextView
        android:id="@+id/landing_time"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/takeoff_time"
        android:hint="@string/landing_time_hint" />

    <TextView
        android:id="@+id/off_time"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/landing_time"
        android:hint="@string/off_time_hint" />

    <Button
        android:id="@+id/button_record"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/off_time"
        android:onClick="recordTime"
        android:padding="5dp"
        android:text="@string/button_record" />

    <Button
        android:id="@+id/button_reset"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/off_time"
        android:layout_toRightOf="@id/button_record"
        android:onClick="resetAllTimes"
        android:padding="5dp"
        android:text="@string/button_reset" />

    <CheckBox
        android:id="@+id/checkbox_ifr"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/button_record"
        android:text="@string/checkbox_ifr"
        android:onClick="ifrCheckboxClicked" />

    <CheckBox
        android:id="@+id/checkbox_cross_country"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/button_record"
        android:layout_toRightOf="@id/checkbox_ifr"
        android:text="@string/checkbox_cross_country"
        android:onClick="crossCountryCheckboxClicked" />

    <Spinner
        android:id="@+id/ifr_type_spinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/checkbox_ifr"
        android:visibility="gone" />

    <TextView
        android:id="@+id/label_ifr_approaches"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/ifr_type_spinner"
        android:hint="@string/ifr_landings_label"
        android:visibility="gone" />

    <logbook.app.custom.widgets.NumberSelector
        android:id="@+id/ifr_landings_selector"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/label_ifr_approaches"
        android:visibility="gone"
        custom:orientation="vertical" />

    <EditText
        android:id="@+id/ifr_hours"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/ifr_landings_selector"
        android:hint="@string/ifr_hours_hint"
        android:inputType="number"
        android:visibility="gone" />

    <EditText
        android:id="@+id/cross_country_hours"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/ifr_hours"
        android:hint="@string/cross_country_hours_hint"
        android:inputType="number"
        android:visibility="gone" />

    <TextView
        android:id="@+id/label_takeoffs_landings"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/cross_country_hours"
        android:hint="@string/takeoffs_landings_label" />

    <logbook.app.custom.widgets.NumberSelector
        android:id="@+id/landings_selector"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/label_takeoffs_landings"
        custom:orientation="horizontal" />

    <Button
        android:id="@+id/button_create_log"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/landings_selector"
        android:onClick="createLog"
        android:padding="5dp"
        android:text="@string/button_create_log" />

</RelativeLayout>

我怎样才能停止 ScrollView每次它的 child 的可见性之一在 View.GONE 之间发生变化时，从滚动到顶部和 View.Visible ？

Answer 1

我想你想在新的可见 View 中向下滚动滚动条 crossCountryHoursTextBox为此，只需像这样滚动滚动条

// scrollview at visible textbox
yourscroll.smoothScrollBy(0,crossCountryHoursTextBox.getTop());