如何在线程或异步任务中运行此代码？

Question

当我尝试运行此代码时，我收到一个关于 strictMode 线程策略的错误，所以我添加了这一行。

StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();     
StrictMode.setThreadPolicy(policy);  

我后来发现这不是我必须在线程或异步任务中运行它的最佳方法，所以我希望在线程或异步任务中运行它。请在回答时帮助编辑我的代码

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// requestWindowFeature(Window.FEATURE_NO_TITLE);
// getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
// WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_live_streaming);

ActionBar actionbar = getSupportActionBar();
actionbar.setDisplayHomeAsUpEnabled(true);
abm = new ActionBarMenu(LiveStreaming.this);

StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
        .permitAll().build();
StrictMode.setThreadPolicy(policy);

if (InternetStatus.getInstance(this).isOnline(this)) {

    XMLParser parser = new XMLParser();
    String xml = parser.getXmlFromUrl(URL); // getting XML from URL
    Document doc = parser.getDomElement(xml); // getting DOM element

    // NodeList nl = doc.getElementsByTagName();

    NodeList studentList = doc.getElementsByTagName("streamingurl");

    // Print total student elements in document
    // System.out.println("Total students: " + studentList.getLength());
    Toast.makeText(getBaseContext(), "Please wait while stream loads",
            Toast.LENGTH_SHORT).show();

    if (studentList != null && studentList.getLength() > 0) {
        for (int i = 0; i < studentList.getLength(); i++) {

            Node node = studentList.item(i);

            if (node.getNodeType() == Node.ELEMENT_NODE) {

                Element e = (Element) node;
    NodeList nodeList = e.getElementsByTagName("andhigh_value");
        theAndroid_HighValue = nodeList.item(0).getChildNodes()
                        .item(0).getNodeValue();

            }

            vid = (VideoView) findViewById(R.id.videoview);
            vid.setVideoPath(theAndroid_HighValue);
        // static final String KEY_IPADHIGH = "ipadhigh_value";
        MediaController mediaController = new MediaController(this);
            mediaController.setAnchorView(vid);
            // vid.setMediaController(mediaController);
            vid.requestFocus();
            vid.start();

        videoBuffering = new ProgressDialog(LiveStreaming.this);
            videoBuffering.setMessage("Loading...Please wait");
            // videoBuffering.setIcon(R.drawable.ic_launcher);
            // videoBuffering.setTitle(R.string.app_name);
        videoBuffering.setProgressStyle(ProgressDialog.STYLE_SPINNER);
            videoBuffering.show();

    vid.setOnErrorListener(new OnErrorListener() {
    @Override
    public boolean onError(MediaPlayer mp, int what,
            int extra) {
            // Log.e(TAG, "Error playing video");
 // Toast.makeText(getBaseContext(),"No Stream Found",Toast.LENGTH_SHORT).show();
 AlertDialog NetAlert = new AlertDialog.Builder(LiveStreaming.this).create();
 NetAlert.setMessage("No Stream Found!");
        NetAlert.setButton("OK",
        new DialogInterface.OnClickListener() {
        public void onClick(
    DialogInterface dialog,int which) {

            // here you can add functions
            // finish();
                    }
                    });
                    NetAlert.show();
                    return true;
                }
            });

            vid.setOnPreparedListener(new OnPreparedListener() {
                @Override
                public void onPrepared(MediaPlayer mp) {

                    videoBuffering.cancel();
                }
            });

        }
    } else {
        Toast.makeText(getBaseContext(), "No Internet Connection",
                Toast.LENGTH_SHORT).show();
        // Toast t =
        // Toast.makeText(this,"You are not online!!!!",8000).show();
        Log.v("Home",
            "############################You are not online!!!!");
    }
 }

 // liveblog_tab = (LinearLayout) findViewById(R.id.liveblog_tab);
 addcom_tab = (ImageView) findViewById(R.id.addcom);

 liveblog = (ImageView) findViewById(R.id.addfull);
 // comments = (LinearLayout) findViewById(R.id.comments);

 FLAG = LIVE_BLOG;

 ourBrow = (WebView) findViewById(R.id.browser);
 // adding webviewclient prevents web-view launching every-time the
 // web-site is visited
 ourBrow.setWebViewClient(new WebViewClient());
 // ourBrow.getSettings().setBuiltInZoomControls(true);
 // ourBrow.getSettings().setSupportZoom(true);
 ourBrow.getSettings().setJavaScriptEnabled(true);
 ourBrow.getSettings().setAllowFileAccess(true);
 ourBrow.loadUrl("http://");
 ourBrow.setWebViewClient(new WebViewClient() {
    public void onReceivedError(WebView view, int errorCode,
            String description, String failingUrl) {
        ourBrow.loadUrl("file:///android_asset/internet.htm");
    }
 });

 addcom_tab.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View arg0) {
        // FLAG = COMMENT;
        // changeView();
        viewCategory();

    }
 });

 liveblog.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {

Intent i = new Intent(LiveStreaming.this, FullVideoView.class);
        i.putExtra("video_url", "theAndroid_HighValue");
        startActivity(i);
    }
});

}

Answer 1

你可以试试下面的方法。

button1.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View arg0) {
                new asyn().execute();
            }
        });

然后像这样创建你的异步任务。

class asyn extends AsyncTask<String, String, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(yourActivityname.this);
            pDialog.setMessage("Loading... Please wait...");
            pDialog.setCancelable(false);
            pDialog.show();
        }

        protected String doInBackground(String... args) {
        if (InternetStatus.getInstance(this).isOnline(this)) {

XMLParser parser = new XMLParser();
String xml = parser.getXmlFromUrl(URL); // getting XML from URL
Document doc = parser.getDomElement(xml); // getting DOM element

// NodeList nl = doc.getElementsByTagName();

NodeList studentList = doc.getElementsByTagName("streamingurl");

// Print total student elements in document
// System.out.println("Total students: " + studentList.getLength());
Toast.makeText(getBaseContext(), "Please wait while stream loads",
        Toast.LENGTH_SHORT).show();

if (studentList != null && studentList.getLength() > 0) {
    for (int i = 0; i < studentList.getLength(); i++) {

        Node node = studentList.item(i);

        if (node.getNodeType() == Node.ELEMENT_NODE) {

            Element e = (Element) node;
NodeList nodeList = e.getElementsByTagName("andhigh_value");
    theAndroid_HighValue = nodeList.item(0).getChildNodes()
                    .item(0).getNodeValue();

        }

        vid = (VideoView) findViewById(R.id.videoview);
        vid.setVideoPath(theAndroid_HighValue);
    // static final String KEY_IPADHIGH = "ipadhigh_value";
    MediaController mediaController = new MediaController(this);
        mediaController.setAnchorView(vid);
        // vid.setMediaController(mediaController);
        vid.requestFocus();
        vid.start();

    videoBuffering = new ProgressDialog(LiveStreaming.this);
        videoBuffering.setMessage("Loading...Please wait");
        // videoBuffering.setIcon(R.drawable.ic_launcher);
        // videoBuffering.setTitle(R.string.app_name);
    videoBuffering.setProgressStyle(ProgressDialog.STYLE_SPINNER);
        videoBuffering.show();

vid.setOnErrorListener(new OnErrorListener() {
@Override
public boolean onError(MediaPlayer mp, int what,
        int extra) {
        // Log.e(TAG, "Error playing video");
     // Toast.makeText(getBaseContext(),"No Stream Found",Toast.LENGTH_SHORT).show();
 AlertDialog NetAlert = new AlertDialog.Builder(LiveStreaming.this).create();
 NetAlert.setMessage("No Stream Found!");
        NetAlert.setButton("OK",
        new DialogInterface.OnClickListener() {
        public void onClick(
    DialogInterface dialog,int which) {
        // here you can add functions
        // finish();
                }
                });
                NetAlert.show();
                return true;
            }
        });

        vid.setOnPreparedListener(new OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mp) {

                videoBuffering.cancel();
            }
        });

    }
} else {
    Toast.makeText(getBaseContext(), "No Internet Connection",
            Toast.LENGTH_SHORT).show();
    // Toast t =
    // Toast.makeText(this,"You are not online!!!!",8000).show();
    Log.v("Home",
        "############################You are not online!!!!");
}
}
            return null;
        }

        protected void onPostExecute(String file_url) {
            pDialog.dismiss();
        }
    }

这里pDialog 是您的ProgressDialog，您可以像这样定义它ProgressDialog pDialog; 或者如果您不想在按钮的点击事件上预先设置此事件，那么您可以直接在onCreate 方法中使用这一行@987654325 @。

编辑

我已经编辑了我的答案，但是您必须对此进行一些必要的更改，我认为它会要求您在某处添加 try and catch 块，然后添加它。

Answer 2

通过这个link学习AsyncTask

并尝试在AsyncTask 的doInBackground 方法中编写您的逻辑

Answer 3

splashHandler.sendEmptyMessageDelayed(0, 3000);


Handler splashHandler= new Handler()
{
    public void handleMessage(android.os.Message msg) 
    {
        switch (msg.what) 
        {
        case 0:

            //Your code is here....
            break;
            default:
                break;
        }
    }
};