Question

我在ListView中有一个单元格，里面有一堆文本。我显示前两行文本，如果超出则以“...”结束。我希望用户能够触摸单元格并使其在视图中动态扩展，显示所有数据。然后，当他们再次触摸细胞时，它会恢复到正常大小。

我看过iOS应用程序这样做，非常酷。有没有办法用Android做到这一点？怎么样？

Closed

Opened

Answer 1

我已经实现了一个适用于所有Android sdk版本的简单代码。

见下面的工作和代码。

Github代码：https://github.com/LeonardoCardoso/Animated-Expanding-ListView

有关我网站的信息：http://android.leocardz.com/animated-expanding-listview/

normal accordion

基本上，您必须创建自定义TranslateAnimation和自定义列表适配器，并且在设置动画时，您必须更新listview项的当前高度并通知适配器此更改。

我们来看看代码。

列出项目布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
       android:id="@+id/text_wrap"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:orientation="horizontal"
       android:paddingBottom="@dimen/activity_vertical_margin"
       android:paddingLeft="@dimen/activity_horizontal_margin"
       android:paddingRight="@dimen/activity_horizontal_margin"
       android:paddingTop="@dimen/activity_vertical_margin" >

       <TextView
           android:id="@+id/text"
           android:layout_width="match_parent"
           android:layout_height="wrap_content"
           android:textSize="18sp" >
       </TextView>

</LinearLayout>

活动布局

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

          <ListView
              android:id="@+id/list"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:divider="@android:color/black"
              android:dividerHeight="3dp" >
          </ListView>

      </RelativeLayout>

列出项目类

public class ListItem {

private String text;
private int collapsedHeight, currentHeight, expandedHeight;
private boolean isOpen;
private ListViewHolder holder;
private int drawable;

public ListItem(String text, int collapsedHeight, int currentHeight,
        int expandedHeight) {
    super();
    this.text = text;
    this.collapsedHeight = collapsedHeight;
    this.currentHeight = currentHeight;
    this.expandedHeight = expandedHeight;
    this.isOpen = false;
    this.drawable = R.drawable.down;
}

public String getText() {
    return text;
}

public void setText(String text) {
    this.text = text;
}

public int getCollapsedHeight() {
    return collapsedHeight;
}

public void setCollapsedHeight(int collapsedHeight) {
    this.collapsedHeight = collapsedHeight;
}

public int getCurrentHeight() {
    return currentHeight;
}

public void setCurrentHeight(int currentHeight) {
    this.currentHeight = currentHeight;
}

public int getExpandedHeight() {
    return expandedHeight;
}

public void setExpandedHeight(int expandedHeight) {
    this.expandedHeight = expandedHeight;
}

public boolean isOpen() {
    return isOpen;
}

public void setOpen(boolean isOpen) {
    this.isOpen = isOpen;
}

public ListViewHolder getHolder() {
    return holder;
}

public void setHolder(ListViewHolder holder) {
    this.holder = holder;
}

public int getDrawable() {
    return drawable;
}

public void setDrawable(int drawable) {
    this.drawable = drawable;
}
}

查看持有人类

public class ListViewHolder {
 private LinearLayout textViewWrap;
 private TextView textView;

 public ListViewHolder(LinearLayout textViewWrap, TextView textView) {
    super();
    this.textViewWrap = textViewWrap;
    this.textView = textView;
 }

 public TextView getTextView() {
        return textView;
 }

 public void setTextView(TextView textView) {
    this.textView = textView;
 }

 public LinearLayout getTextViewWrap() {
    return textViewWrap;
 }

 public void setTextViewWrap(LinearLayout textViewWrap) {
    this.textViewWrap = textViewWrap;
 }
}

自定义动画类

    public class ResizeAnimation extends Animation {
    private View mView;
    private float mToHeight;
    private float mFromHeight;

    private float mToWidth;
    private float mFromWidth;

    private ListAdapter mListAdapter;
    private ListItem mListItem;

    public ResizeAnimation(ListAdapter listAdapter, ListItem listItem,
            float fromWidth, float fromHeight, float toWidth, float toHeight) {
        mToHeight = toHeight;
        mToWidth = toWidth;
        mFromHeight = fromHeight;
        mFromWidth = fromWidth;
        mView = listItem.getHolder().getTextViewWrap();
        mListAdapter = listAdapter;
        mListItem = listItem;
        setDuration(200);
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        float height = (mToHeight - mFromHeight) * interpolatedTime
                + mFromHeight;
        float width = (mToWidth - mFromWidth) * interpolatedTime + mFromWidth;
        LayoutParams p = (LayoutParams) mView.getLayoutParams();
        p.height = (int) height;
        p.width = (int) width;
        mListItem.setCurrentHeight(p.height);
        mListAdapter.notifyDataSetChanged();
    }
  }

自定义列表适配器类

public class ListAdapter extends ArrayAdapter<ListItem> {
private ArrayList<ListItem> listItems;
private Context context;

public ListAdapter(Context context, int textViewResourceId,
    ArrayList<ListItem> listItems) {
super(context, textViewResourceId, listItems);
this.listItems = listItems;
this.context = context;
}

@Override
@SuppressWarnings("deprecation")
public View getView(int position, View convertView, ViewGroup parent) {
ListViewHolder holder = null;
ListItem listItem = listItems.get(position);

if (convertView == null) {
    LayoutInflater vi = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    convertView = vi.inflate(R.layout.list_item, null);

    LinearLayout textViewWrap = (LinearLayout) convertView
            .findViewById(R.id.text_wrap);
    TextView text = (TextView) convertView.findViewById(R.id.text);

    holder = new ListViewHolder(textViewWrap, text);
} else
    holder = (ListViewHolder) convertView.getTag();

holder.getTextView().setText(listItem.getText());

LayoutParams layoutParams = new LayoutParams(LayoutParams.FILL_PARENT,
        listItem.getCurrentHeight());
holder.getTextViewWrap().setLayoutParams(layoutParams);

holder.getTextView().setCompoundDrawablesWithIntrinsicBounds(
        listItem.getDrawable(), 0, 0, 0);

convertView.setTag(holder);

listItem.setHolder(holder);

return convertView;
}

}

主要活动

public class MainActivity extends Activity {

private ListView listView;
private ArrayList<ListItem> listItems;
private ListAdapter adapter;

private final int COLLAPSED_HEIGHT_1 = 150, COLLAPSED_HEIGHT_2 = 200,
    COLLAPSED_HEIGHT_3 = 250;

private final int EXPANDED_HEIGHT_1 = 250, EXPANDED_HEIGHT_2 = 300,
    EXPANDED_HEIGHT_3 = 350, EXPANDED_HEIGHT_4 = 400;

private boolean accordion = true;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

listView = (ListView) findViewById(R.id.list);

listItems = new ArrayList<ListItem>();
mockItems();

adapter = new ListAdapter(this, R.layout.list_item, listItems);

listView.setAdapter(adapter);

listView.setOnItemClickListener(new OnItemClickListener() {

    @Override
    public void onItemClick(AdapterView<?> parent, View view,
            int position, long id) {
        toggle(view, position);
    }
});
}

private void toggle(View view, final int position) {
ListItem listItem = listItems.get(position);
listItem.getHolder().setTextViewWrap((LinearLayout) view);

int fromHeight = 0;
int toHeight = 0;

if (listItem.isOpen()) {
    fromHeight = listItem.getExpandedHeight();
    toHeight = listItem.getCollapsedHeight();
} else {
    fromHeight = listItem.getCollapsedHeight();
    toHeight = listItem.getExpandedHeight();

    // This closes all item before the selected one opens
    if (accordion) {
        closeAll();
    }
}

toggleAnimation(listItem, position, fromHeight, toHeight, true);
}

private void closeAll() {
int i = 0;
for (ListItem listItem : listItems) {
    if (listItem.isOpen()) {
        toggleAnimation(listItem, i, listItem.getExpandedHeight(),
                listItem.getCollapsedHeight(), false);
    }
    i++;
}
}

private void toggleAnimation(final ListItem listItem, final int position,
    final int fromHeight, final int toHeight, final boolean goToItem) {

ResizeAnimation resizeAnimation = new ResizeAnimation(adapter,
        listItem, 0, fromHeight, 0, toHeight);
resizeAnimation.setAnimationListener(new AnimationListener() {

    @Override
    public void onAnimationStart(Animation animation) {
    }

    @Override
    public void onAnimationRepeat(Animation animation) {
    }

    @Override
    public void onAnimationEnd(Animation animation) {
        listItem.setOpen(!listItem.isOpen());
        listItem.setDrawable(listItem.isOpen() ? R.drawable.up
                : R.drawable.down);
        listItem.setCurrentHeight(toHeight);
        adapter.notifyDataSetChanged();

        if (goToItem)
            goToItem(position);
    }
});

listItem.getHolder().getTextViewWrap().startAnimation(resizeAnimation);
}

private void goToItem(final int position) {
listView.post(new Runnable() {
    @Override
    public void run() {
        try {
            listView.smoothScrollToPosition(position);
        } catch (Exception e) {
            listView.setSelection(position);
        }
    }
});
}

private void mockItems() {
listItems
        .add(new ListItem(
                "Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.",
                COLLAPSED_HEIGHT_1, COLLAPSED_HEIGHT_1,
                EXPANDED_HEIGHT_1));

listItems
        .add(new ListItem(
                "Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.",
                COLLAPSED_HEIGHT_2, COLLAPSED_HEIGHT_2,
                EXPANDED_HEIGHT_2));

listItems
        .add(new ListItem(
                "Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.",
                COLLAPSED_HEIGHT_3, COLLAPSED_HEIGHT_3,
                EXPANDED_HEIGHT_3));

listItems
        .add(new ListItem(
                "Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo.",
                COLLAPSED_HEIGHT_2, COLLAPSED_HEIGHT_2,
                EXPANDED_HEIGHT_4));

listItems
        .add(new ListItem(
                "At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.",
                COLLAPSED_HEIGHT_1, COLLAPSED_HEIGHT_1,
                EXPANDED_HEIGHT_4));

listItems
        .add(new ListItem(
                "Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.",
                COLLAPSED_HEIGHT_2, COLLAPSED_HEIGHT_2,
                EXPANDED_HEIGHT_4));

listItems
        .add(new ListItem(
                "Temporibus autem quibusdam et aut officiis debitis aut rerum necessitatibus saepe eveniet ut et voluptates repudiandae sint et molestiae non recusandae.",
                COLLAPSED_HEIGHT_3, COLLAPSED_HEIGHT_3,
                EXPANDED_HEIGHT_3));

listItems
        .add(new ListItem(
                "Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.",
                COLLAPSED_HEIGHT_1, COLLAPSED_HEIGHT_1,
                EXPANDED_HEIGHT_4));

    }

}

Answer 2

以下是Udinic的例子。它有listview项目展开动画，只需要API级别4 +

ExpandAnimationExample

onItemClick事件中的

使用ExpandAnimation

/**
* This animation class is animating the expanding and reducing the size of a view.
* The animation toggles between the Expand and Reduce, depending on the current state of the view
* @author Udinic
*
*/
public class ExpandAnimation extends Animation {
    private View mAnimatedView;
    private LayoutParams mViewLayoutParams;
    private int mMarginStart, mMarginEnd;
    private boolean mIsVisibleAfter = false;
    private boolean mWasEndedAlready = false;

    /**
* Initialize the animation
* @param view The layout we want to animate
* @param duration The duration of the animation, in ms
*/
    public ExpandAnimation(View view, int duration) {

        setDuration(duration);
        mAnimatedView = view;
        mViewLayoutParams = (LayoutParams) view.getLayoutParams();

        // decide to show or hide the view
        mIsVisibleAfter = (view.getVisibility() == View.VISIBLE);

        mMarginStart = mViewLayoutParams.bottomMargin;
        mMarginEnd = (mMarginStart == 0 ? (0- view.getHeight()) : 0);

        view.setVisibility(View.VISIBLE);
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        super.applyTransformation(interpolatedTime, t);

        if (interpolatedTime < 1.0f) {

            // Calculating the new bottom margin, and setting it
            mViewLayoutParams.bottomMargin = mMarginStart
                    + (int) ((mMarginEnd - mMarginStart) * interpolatedTime);

            // Invalidating the layout, making us seeing the changes we made
            mAnimatedView.requestLayout();

        // Making sure we didn't run the ending before (it happens!)
        } else if (!mWasEndedAlready) {
            mViewLayoutParams.bottomMargin = mMarginEnd;
            mAnimatedView.requestLayout();

            if (mIsVisibleAfter) {
                mAnimatedView.setVisibility(View.GONE);
            }
            mWasEndedAlready = true;
        }
    }
}

详细用法在项目中。

Answer 3

SDK中有一个示例，它可以帮助您。

显然，它被称为ExpandableList。位于API演示（/ docs / resources / samples / ApiDemos / src / com / example / android / apis / view）

Answer 4

以下是我要做的选项：

在ListView的BaseAdapter中添加一个if语句，该语句将在ListView中查询当前所选项目。如果您正在绘制的当前项目（在BaseAdapter中）是所选项目的位置，则改为创建展开的视图。然后恢复正常视图创建。

编辑：

我假设您希望一次扩展一（1）个项目而不是整个列表，我将此作为一个选项。

如何让Android中的ListView中的单元格在触摸时垂直展开和收缩？

4 个答案: