LinearLayout无法在ScrollView中滚动

Question

我试图弄清楚为什么此LinearLayout没有滚动：

<ScrollView
    android:layout_width="match_parent"
    android:fillViewport="true"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="match_parent">

   <LinearLayout
    android:id="@+id/linearLayout"
    android:orientation="vertical"
    android:weightSum="2"
    android:gravity="center_horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="35dp"
        android:text="TITLE 1"
        android:textSize="30sp" />

    <ListView
        android:id="@+id/listView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20sp" />

</LinearLayout>
</ScrollView>

我正在以编程方式将textView和listView添加到linearLayout，并且页面被切成两半。滚动的唯一内容是listViews。

Answer 1

尝试此代码

<androidx.core.widget.NestedScrollView
    android:layout_width="match_parent"
    android:fillViewport="true"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="match_parent">

   <LinearLayout
    android:id="@+id/linearLayout"
    android:orientation="vertical"
    android:weightSum="2"
    android:gravity="center_horizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="35dp"
        android:text="TITLE 1"
        android:textSize="30sp" />

    <ListView
        android:id="@+id/listView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20sp" />

</LinearLayout>
</androidx.core.widget.NestedScrollView>

Answer 2

列表视图不会滚动，因为它是嵌套的。如果在Scrollview中使用listview，它们可能会互相干扰。 （两个滚动）您应该自定义Scrollview，这样当您触摸Listview区域时，scrollview将停止滚动。

1）创建新类：CustomScrollView并从ScrollView扩展它>

2）将xml <ScrollView>更改为自定义滚动视图：<com.your_package_name.CustomScrollView>

CustomScrollView.java:

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ScrollView;

public class CustomScrollView extends ScrollView {
    public CustomScrollView(Context context) {
        super(context);
    }

    public CustomScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public CustomScrollView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        final int action = ev.getAction();
        switch (action) {
            case MotionEvent.ACTION_DOWN:
                //Log.i("CustomScrollView", "onInterceptTouchEvent: DOWN super false" );
                super.onTouchEvent(ev);
                break;

            case MotionEvent.ACTION_MOVE:
                return false; // redirect MotionEvents to ourself

            case MotionEvent.ACTION_CANCEL:
                // Log.i("CustomScrollView", "onInterceptTouchEvent: CANCEL super false" );
                super.onTouchEvent(ev);
                break;

            case MotionEvent.ACTION_UP:
                //Log.i("CustomScrollView", "onInterceptTouchEvent: UP super false" );
                return false;

            default:
                //Log.i("CustomScrollView", "onInterceptTouchEvent: " + action );
                break;
        }

        return false;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        super.onTouchEvent(ev);
        //Log.i("CustomScrollView", "onTouchEvent. action: " + ev.getAction() );
        return true;
    }
}