小编ali*_*sce的帖子

我观察到一个与 WPF DataGrid 验证相关的非常奇怪的问题，该问题仅在某些情况下发生。为了重现这个问题，我有一个测试窗口。

<Window x:Class="TEST.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:TEST"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"></RowDefinition>
            <RowDefinition Height="Auto">   
            </RowDefinition>
        </Grid.RowDefinitions>
        <DataGrid x:Name="datagrid" AutoGenerateColumns="True" Grid.Row="0" ColumnWidth="*"></DataGrid>
        <Button Click="Button_Click" Grid.Row="1">Fill Data</Button>
    </Grid>
</Window>

这是背后的代码：

namespace TEST
{
     
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
        ObservableCollection<Person> list = null;
        private void Button_Click(object sender, RoutedEventArgs e)
        {
         list=   new ObservableCollection<Person>();
           
            for (int i = 0; i < 100; i++)
            {
                list.Add(new Person() { Age = 20, …

我正在尝试获取相机预览并将其中一部分用于在ImageView上显示.此代码在模拟器上正常工作但在设备上崩溃并出现以下错误:

A/libc(2659):致命信号11(SIGSEGV)位于0x42e612a9(代码= 2),线程2659

我看了很多与SIGSEGV错误相关的问题,但我找不到任何解决这个问题的方法.我的设备和模拟器是Android 4.1.2

Size sizeOrgnl;
Rect newRect;
ByteArrayOutputStream newStream;
Bitmap newPicture;
ImageView imgView;  

@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int w, int h) {

     camera=Camera.open();
        if(camera!=null)
        { try
        {
            List<Size> cmszs=camera.getParameters().getSupportedPictureSizes();
            for(int i=0;i<cmszs.size();i++)
            {
                if(cmszs.get(i).width<500&&(cmszs.get(i).width>400))
                {camera.getParameters().setPictureSize(cmszs.get(i).width, cmszs.get(i).height);}

            }
            camera.setDisplayOrientation(90);
            camera.setPreviewDisplay(arg0);
            camera.stopPreview();
              camera.startPreview();
             Thread.sleep(500);
             newStream=new ByteArrayOutputStream();
                 imgView=(ImageView)findViewById(R.id.imageView1);
            camera.setPreviewCallback(new Camera.PreviewCallback() {

                @Override
                public void onPreviewFrame(byte[] data, Camera camera) {

                    if(sizeOrgnl==null)
                    {sizeOrgnl=camera.getParameters().getPictureSize();
                    newRect=new Rect(sizeOrgnl.width/2-20,sizeOrgnl.height/2-20,sizeOrgnl.width/2+20,sizeOrgnl.height/2+20);                    
                    }
                    YuvImage    img = new YuvImage(data, ImageFormat.NV21, sizeOrgnl.width, sizeOrgnl.height, null);
                    newStream=new ByteArrayOutputStream();
                    img.compressToJpeg(newRect, 90, newStream);                 

                    newPicture …