Question

早上好StackOverFlow 我在Handler遇到了一些问题我想尝试MainActivity我的 Client.java < / strong> 50秒后也会发送消息并停止客户端和该工作，但我必须在设置中ip_txt或term_txt的每次更改时重新打开连接。的java （通过单击按钮将数据从EditText保存到DB）

这是我的 MainActivity ：

public class MainActivity extends AppCompatActivity { Server server; Client client; Handler handler = new Handler(); Runnable runnable = new Runnable() { @Override public void run() { new ConnectTask().execute(""); if (client != null) { client.sendMessage("IP#" + ipp + " " + "N#" + trm); } if (client != null) { client.stopClient(); } } }; settings Settings; public static TextView terminale, indr, msg; TextView log; String ipp,trm; DataBaseHandler myDB; allert Allert; SharedPreferences prefs; String s1 = "GAB Tamagnini SRL © 2017 \n" + "Via Beniamino Disraeli, 17,\n" + "42124 Reggio Emilia \n" + "Telefono: 0522 / 38 32 22 \n" + "Fax: 0522 / 38 32 72 \n" + "Partita IVA, Codice Fiscale \n" + "Reg. Impr. di RE 00168780351 \n" + "Cap. soc. € 50.000,00 i.v. \n" + "" + "REA n. RE-107440 \n" + "presso C.C.I.A.A. di Reggio Emilia"; ImageButton settings, helps, allerts, home; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Utils.darkenStatusBar(this, R.color.colorAccent); server = new Server(this); myDB = DataBaseHandler.getInstance(this); msg = (TextView) findViewById(R.id.msg); log = (TextView) findViewById(R.id.log_avviso); settings = (ImageButton) findViewById(R.id.impo); helps = (ImageButton) findViewById(R.id.aiut); allerts = (ImageButton) findViewById(R.id.msge); home = (ImageButton) findViewById(R.id.gab); terminale = (TextView) findViewById(R.id.terminal); indr = (TextView) findViewById(R.id.indr); final Cursor cursor = myDB.fetchData(); if (cursor.moveToFirst()) { do { indr.setText(cursor.getString(1)); terminale.setText(cursor.getString(2)); Client.SERVER_IP = cursor.getString(1); trm = cursor.getString(2); } while (cursor.moveToNext()); } WifiManager wm = (WifiManager) getSystemService(WIFI_SERVICE); ipp = Formatter.formatIpAddress(wm.getConnectionInfo().getIpAddress()); handler.postDelayed(runnable,5000); cursor.close(); server.Parti(); home.setOnClickListener(new View.OnClickListener() { int counter = 0; @Override public void onClick(View view) { counter++; if (counter == 10) { AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this); builder.setCancelable(true); builder.setMessage(s1); builder.show(); counter = 0; } } }); settings.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent impostazioni = new Intent(getApplicationContext(), settingsLogin.class); startActivity(impostazioni); } }); helps.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent pgHelp = new Intent(getApplicationContext(), help.class); startActivity(pgHelp); } }); allerts.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Server.count = 0; SharedPreferences prefs = getSharedPreferences("MY_DATA", MODE_PRIVATE); SharedPreferences.Editor editor = prefs.edit(); editor.clear(); editor.apply(); msg.setVisibility(View.INVISIBLE); Intent pgAlert = new Intent(getApplicationContext(), allert.class); startActivity(pgAlert); } }); } @Override protected void onDestroy() { super.onDestroy(); server.onDestroy(); } public class ConnectTask extends AsyncTask<String, String, Client> { @Override protected Client doInBackground(String... message) { client = new Client(new Client.OnMessageReceived() { @Override public void messageReceived(String message) { publishProgress(message); } }); client.run(); return null; } @Override protected void onProgressUpdate(String... values) { super.onProgressUpdate(values); Log.d("test", "response " + values[0]); } } }

这是我的 settings.java ：

public class settings extends AppCompatActivity { TextView indr; Client client; EditText ip_txt,term_txt; ImageButton home; Button save; DataBaseHandler myDB; MainActivity activity; String ipp; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); myDB = DataBaseHandler.getInstance(this); setContentView(R.layout.activity_settings); Utils.darkenStatusBar(this, R.color.colorAccent); home = (ImageButton) findViewById(R.id.stgbtn); indr = (TextView) findViewById(R.id.ipp); ip_txt = (EditText) findViewById(R.id.ip); term_txt = (EditText) findViewById(R.id.nTermin); save = (Button) findViewById(R.id.save); Cursor cursor = myDB.fetchData(); if(cursor.moveToFirst()){ do { ip_txt.setText(cursor.getString(1)); term_txt.setText(cursor.getString(2)); }while(cursor.moveToNext()); } cursor.close(); AddData(); home.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { finish(); } }); WifiManager wm = (WifiManager) getSystemService(WIFI_SERVICE); ipp = Formatter.formatIpAddress(wm.getConnectionInfo().getIpAddress()); indr.setText(ipp); } public void AddData() { save.setOnClickListener( new View.OnClickListener() { @Override public void onClick(View v) { myDB.insertData(ip_txt.getText().toString(), term_txt.getText().toString()); MainActivity.indr.setText(ip_txt.getText().toString()); MainActivity.terminale.setText(term_txt.getText().toString()); Client.SERVER_IP = ip_txt.getText().toString(); finish(); } } ); } }

（如果我没有解释，我想在应用程序启动时启动 handler 和 在我更改 EditText ip_txt 或 {{1}中的数据后立即重新启动或立即启动它 }）

Answer 1

我会创建变量来存储处理程序和runnable，然后当你想重新启动它时只需使用：

yourHandler.removeCallback(yourRunnable);
yourHandler.postDelayed(yourRunnable,time);

并启动它，就像你那样做，

yourHandler.postDelayed(yourRunnable,5000);

希望就是你要找的。

如何创建它们：

public class ClassName{
    Handler yourHandler = new Handler();
    Runnable yourRunnable = new Runnable(){
        @Override
        public void run() {
            //yourCode
        }
    };
    // Rest of class code

}

与您在代码中的操作相同，但是在变量中。

如何在更改数据值后重新启动Handler？

1 个答案: