显示 Toast 消息

Question

我想从 class 生成一个 Toast，但没有从中扩展视图。
我的程序中有 3 个 classes。它们是：

public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Intent screenIntent = new Intent(this, Screen.class);
    this.startActivity(screenIntent);

StartVoiceRecognition StartVoiceRecognitionChild = new StartVoiceRecognition();
    StartVoiceRecognitionChild.makeToast();
    }
}

,

public class Screen extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.screen);
    //species field
    tvSpecies = this.findViewById(R.id.textboxSpeciesxml);
    tvSpecies.setText(MainActivity.szSpecies);
    ...
    }
}

和

public class StartVoiceRecognition extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
}
public void makeToast(Context context) {
    Toast.makeText(getApplicationContext(), "toast content here", Toast.LENGTH_SHORT).show();
    }
}

StartVoiceRecognition class 中的 Toast 导致 Screen class 中的布局被破坏。如何在 StartVoiceRecognition 中加入 Toast，这样就不会发生这种情况？

Answer 1

将此方法放在另一个 class 中。一般我们把这些常用的方法放在一个叫Utils的包里，你想用哪里就用什么。

public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    ...
StartVoiceRecognition.makeToast(this, "This is a Toast msg.");
    }
}

和

public class StartVoiceRecognition extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    }
public static void makeToast(Context mContext,String message){
    Toast.makeText(mContext, message, Toast.LENGTH_LONG).show();
    }
}

显示 Toast 消息

Displaying Toast message

android

android-toast