java在另一个类中调用AlertDialog

Question

我想创建一个java类来保存我的应用程序的所有警报。我想使这些方法是静态的，这样它们更容易调用。这是我的密码

警报级别

public class Alerts {

    // Player has not selected a team
    public static void noPlayerTeam(View view) {
        AlertDialog.Builder builder = new AlertDialog.Builder(view);
        builder.setMessage("Select your team.");
        builder.setCancelable(true);

        builder.setNeutralButton(
                "Okay",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();
                    }
                });

        AlertDialog a = builder.create();
        a.show();
    }
}

访问权限代码

Alerts.noPlayerTeam(view);

文档显示AlertDialog.Builder(Context context)

我正在努力将活动的上下文获取到Alert类。上面代码的错误是错误：（13,63）错误：不兼容的类型：视图无法转换为上下文

我知道代码是有效的，因为我可以在与活动相同的脚本中执行它

Answer 1

用view.getContext()代替view：

    AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext());

需要将有效的上下文（UI-Context）传递给构建器构造函数以获取AlertDialog实例

Answer 2

试试这个

• 把这个放到Constant

---

public static void alertDialogShow(Context context, String message)
    {
        final AlertDialog alertDialog = new AlertDialog.Builder(context).create();
        alertDialog.setMessage(message);
        alertDialog.setButton("OK", new DialogInterface.OnClickListener() 
        {
            public void onClick(DialogInterface dialog, int which) 
            {
                alertDialog.dismiss();
          } 
        }); 
        alertDialog.show();
    }

---

• 打电话给Activity

---

Constant.alertDialogShow(YourActivity.this,"Your Error Message");

Answer 3

警报的通用类

public class Alert {
    // Alert with Message and ok
    public static void showAlertDialog(Context context,String title ,String msg){

        AlertDialog.Builder builder=new AlertDialog.Builder(context);
        builder.setTitle(title);
        builder.setMessage(msg);
        builder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
            }});
        builder.create().show();
    }
    // Alert with Message and ok Click Event
    public static void showAlertDialog(Context context, String title ,String msg, DialogInterface.OnClickListener listener){

        AlertDialog.Builder builder=new AlertDialog.Builder(context);
        builder.setTitle(title);
        builder.setMessage(msg);
        builder.setPositiveButton("OK", (DialogInterface.OnClickListener) listener);
        builder.setNegativeButton("Cancel",(DialogInterface.OnClickListener) listener);
        builder.create().show();
    }
}

在主要活动课中

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //Alert.showAlertDialog(this,"Testing","Demooo");

        Alert.showAlertDialog(this,"Testing","Demoooooo", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                if (which==DialogInterface.BUTTON_POSITIVE) {
                    //Your Code
                }else
                    {
                    //Your Code
                }

            }});
    }
}