java Toast并没有显示在Android应用程序中，但它首先被显示，然后在两天后停止

Question

我对Android编程非常陌生。。我在下面列出了我的代码MainActivity.java和activity_main.xml。我尝试过以下解决方案，但没有效果

1. 仅使用this
2. 使用getapplicationcontext()
3. 使用getbasecontext()

---

public class MainActivity extends ActionBarActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Button text2 = (Button) findViewById(R.id.text2);
    final  WifiManager wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE); 

    text2.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            if(wifiManager.isWifiEnabled())  {
                wifiManager.setWifiEnabled(false);
                Toast.makeText(getApplicationContext(), "Disabled", Toast.LENGTH_LONG).show();

            }

        }

    }); // Disabling/Enabling Wifi Mechanism 

}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override

public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}

Answer 1

Toast.makeText(MainActivity.this, "Disabled", Toast.LENGTH_LONG).show();

尝试使用活动上下文而不是应用程序上下文。有关更详细的说明，请参阅此链接：

When to call activity context OR application context?