Question

我有一个奇怪的问题。我有这个Android应用程序，应该从URL导致一个文本文件的一些数据。它有18行和每行一个项目，看起来像这样：

万事达

名称

123456789

1004

56

5000

（这是一项任务，所有数据显然是假的）

我有这个：

public class CreditCard {

    //set up method to get and return data as arraylist
    public ArrayList<String> ccArray(){
        ArrayList<String> ccInfo = new ArrayList<String>();

        //array set up. time to get data
        try {
            URL urlDat = new URL("url");
            Scanner urlScn = new Scanner(urlDat.openStream());
            while (urlScn.hasNext()){
                ccArray().add(urlScn.nextLine() + "\n");
            }

        }catch (MalformedURLException URLe){
            //handle exception

        }
        catch (IOException IOe){
            //handle exception
        }
        return ccInfo;
    }
}

所以我可以将数组传递给main方法（或者类中的另一个方法，还不确定）。我有一个按钮，在主方法中运行displayCreditCards：

public void displayCreditCards(View view) throws IOException {
        TextView tv1;

        tv1 = (TextView) findViewById(R.id.text_main);
        tv1.setText("Data will appear here");

        //create objects to det data and make profiles
        CreditCard ccObj = new CreditCard();


        tv1.setText(ccObj.ccArray().toString());
}

但是，这会导致应用程序无法响应，我从android获得了等待/关闭对话框。我不确定如何解释logcat：

10-04 18:27:01.204    9036-9036/? I/art﹕ Not late-enabling -Xcheck:jni (already on)
10-04 18:27:01.204    9036-9036/? I/art﹕ Late-enabling JIT
10-04 18:27:01.206    9036-9036/? I/art﹕ JIT created with code_cache_capacity=2MB compile_threshold=1000
10-04 18:27:01.257    9036-9036/? W/System﹕ ClassLoader referenced unknown path: /data/app/com.example.pat.displaycc-2/lib/x86
10-04 18:27:01.396    9036-9058/com.example.pat.displaycc D/OpenGLRenderer﹕ Use EGL_SWAP_BEHAVIOR_PRESERVED: true
10-04 18:27:01.400    9036-9036/com.example.pat.displaycc D/﹕ HostConnection::get() New Host Connection established 0xad7ad9a0, tid 9036
10-04 18:27:01.468    9036-9058/com.example.pat.displaycc D/﹕ HostConnection::get() New Host Connection established 0xad7ade40, tid 9058
10-04 18:27:01.471    9036-9058/com.example.pat.displaycc I/OpenGLRenderer﹕ Initialized EGL, version 1.4
10-04 18:27:01.520    9036-9058/com.example.pat.displaycc W/EGL_emulation﹕ eglSurfaceAttrib not implemented
10-04 18:27:01.521    9036-9058/com.example.pat.displaycc W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xad7917c0, error=EGL_SUCCESS
10-04 18:27:04.841    9036-9036/com.example.pat.displaycc W/art﹕ Before Android 4.1, method int android.support.v7.internal.widget.ListViewCompat.lookForSelectablePosition(int, boolean) would have incorrectly overridden the package-private method in android.widget.ListView
10-04 18:27:04.874    9036-9058/com.example.pat.displaycc W/EGL_emulation﹕ eglSurfaceAttrib not implemented
10-04 18:27:04.874    9036-9058/com.example.pat.displaycc W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xad791c20, error=EGL_SUCCESS
10-04 18:27:06.138    9036-9058/com.example.pat.displaycc E/Surface﹕ getSlotFromBufferLocked: unknown buffer: 0xab80f0d0
10-04 18:27:11.564    9036-9058/com.example.pat.displaycc W/EGL_emulation﹕ eglSurfaceAttrib not implemented
10-04 18:27:11.564    9036-9058/com.example.pat.displaycc W/OpenGLRenderer﹕ Failed to set EGL_SWAP_BEHAVIOR on surface 0xad791c00, error=EGL_SUCCESS
10-04 18:27:13.108    9036-9058/com.example.pat.displaycc E/Surface﹕ getSlotFromBufferLocked: unknown buffer: 0xab80f060

我不知道为什么它会挂在我身上，任何想法？

Answer 1

我认为问题是您在使用后不要关闭扫描仪。你应该总是在try-catch之后添加一个finally {}块，你应该在那里调用

urlScan.close() and
urlDat.close()

按住按钮

1 个答案: