ListFragment显示数据时的延迟

发布于 2024-11-08 02:18:28 字数 2109 浏览 6 评论 0原文

首先感谢所有让我的 Android 开发之旅变得更加轻松的用户。然而，我遇到了一种没有找到解决方案的情况，所以这里是：

我有一个活动，其中包含旨在相互交互的各种片段。其中包括：

一个包含 GridView 的片段，该 GridView 由 Sqlite 数据库中的一个表中的 SimpleCursorAdapter 填充

// 网格功能

公共无效填充网格（）{
dba = new myDB(getActivity().getApplicationContext());
dba.open();
光标c = dba.getRows();
如果（c！=空）{
String[] 列 = new String[]{col_1, col_2, col_3, col_4};
int[] to = new int[]{R.id.grid_id, R.id.grid_desc, R.id.grid_value, R.id.grid_image};

newAdapter = new SimpleCursorAdapter(getActivity(), R.layout.grid_item, c, columns, to); 

视图 v = getView();
GridView gv = (GridView)v.findViewById(R.id.sale_grid);
gv.setAdapter(newAdapter);
gv.setOnItemClickListener(itemSelected);

}
}

一个 ListFragment，由另一个表中的另一个 SimpleCursorAdapter 填充 // 列表功能

public void PopulateList(int index){
Log.v("销售列表", "填充列表开始");
dba.open();
光标cursor = dba.getList(index);
if（光标！=空）{
String[] 列 = new String[]{col_1, col_2, col_3, col_4, col_5};

int[] to = new int[]{R.id.code, R.id.description, R.id.qty, R.id.price};

newAdapter = new SimpleCursorAdapter(getActivity(), R.layout.list_row, 光标, 列, to); 
this.setListAdapter(newAdapter);

}
dba.close();

}

当用户从 GridView 中选择某些内容时，Activity 会将该项目插入 ListView 的表中，然后重新初始化它。
<前><代码>@Override 公共无效onGridClicked（长值）{ insertItem(value.toString()); } //做事公共无效insertItem（字符串结果）{ // 添加项目 dba.addItem(结果，数量，索引); //重新填充面板漫长的开始；长尾；开始 = System.currentTimeMillis(); 刷新面板（索引）；结束 = System.currentTimeMillis(); Log.v("刷新列表：", "时间"+(end-start)); } 私有无效刷新面板（int索引）{ lf.PopulateList(索引); ListView lv = lf.getListView(); lv.setSelection(lv.getCount()-1); }

现在解决问题：当我查看日志并记录每个步骤时。整个过程花费的时间不超过 50-70 毫秒，但从我单击网格到更新 ListView 的时间，我确实可以数到 2-3 秒。看来问题在于 ListFragment 以及 setListAdapter() 和刷新视图所需的时间。

我尝试了各种方法来解决此问题，例如 1. 使用接口来侦听选择或直接从 GridView 片段调用它 2. 使用 newadapter.changecursor(c)< 调用 ListFragment 中的辅助函数/code> 或 newadapter.getCursor().requery() 3. 此的其他变体...

但它似乎总是永远需要任何帮助..

原文

First off thanks to all the users who have made my android developing adventure so much easier. I have, however, come across a situation for which I don't find a solution so here goes:

I have an Activity which contains various Fragments which are intended to interact with each other. These include:

a Fragment containing a GridView populated by a SimpleCursorAdapter from one table in the Sqlite db

// Grid Functionality

public void PopulateGrid(){
dba = new myDB(getActivity().getApplicationContext());
dba.open();
Cursor c = dba.getRows();
if (c!=null){
String[] columns = new String[]{col_1, col_2, col_3, col_4};
int[] to = new int[]{R.id.grid_id, R.id.grid_desc, R.id.grid_value, R.id.grid_image};

newAdapter = new SimpleCursorAdapter(getActivity(), R.layout.grid_item, c, columns, to); 

View v = getView();
GridView gv = (GridView)v.findViewById(R.id.sale_grid);
gv.setAdapter(newAdapter);
gv.setOnItemClickListener(itemSelected);

}
}

a ListFragment which is populated by another SimpleCursorAdapter from a different table
// List Functionality

public void PopulateList(int index){
Log.v("sell list", "Populate list started");
dba.open();
Cursor cursor = dba.getList(index);
if (cursor!=null){
String[] columns = new String[]{col_1, col_2, col_3, col_4, col_5};

int[] to = new int[]{R.id.code, R.id.description, R.id.qty, R.id.price};

newAdapter = new SimpleCursorAdapter(getActivity(), R.layout.list_row, cursor, columns, to); 
this.setListAdapter(newAdapter);

}
dba.close();

}

When the user selects something from the GridView, the Activity inserts the item in the ListView's table and then reinitializes it.

@Override
public void onGridClicked(Long value) {
insertItem(value.toString());
}
//do stuff

public void insertItem(String result) {

    // Add item
    dba.addItem(result, qty, index);
    //Re-populate Panels 
    long start;
    long end;

    start = System.currentTimeMillis();
    refreshPanels(index);
    end = System.currentTimeMillis();
    Log.v("Refresh List:", "Time"+(end-start));

}
private void refreshPanels(int index){
    lf.PopulateList(index);
    ListView lv = lf.getListView();
    lv.setSelection(lv.getCount()-1);

}

Now for the problem: When I look at the logs and Log each step. This entire process take no more than 50-70 ms but from the time I click on the Grid to the time the ListView is updated I can literally count 2-3 seconds.
It seems that the issue lies in the ListFragment and the time it takes to setListAdapter() and refresh the View.

I have tried various ways of going about this such as 1. using an Interface to listen for the selection or calling it directly from the GridView fragment 2. calling a secondary function in the ListFragment with either newadapter.changecursor(c) or newadapter.getCursor().requery() 3. other variants of this...

But it always seems to take forever any help please..

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