android – 在类中扩展BroadcastReceiver使用上下文

当android中的警报响起时,我想创建一个AlertDialog.此外,我想创建一个通知,具体取决于用户在对话框上的单选按钮中单击的选项.
当我尝试使用context或getApplicationContext()时出现问题.

这是我的代码：

public void onReceive(final Context context, Intent intent)
{
    final CharSequence[] items = {" I'm taking the dose now! "," Remind again in ten minutes. "," Ignore for now. "};
    String doseName = intent.getStringExtra("doseName");
    Toast.makeText(context, "Take medicine: " + doseName, Toast.LENGTH_LONG).show();

    AlertDialog.Builder builder = new AlertDialog.Builder(context);
    builder.setTitle("It's time for your medicine.");
    builder.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
            switch(item)
            {
            case 0:
                Toast.makeText(context, "Good.", Toast.LENGTH_SHORT).show();
                break;
            case 1:
                Toast.makeText(context, "Reminder set in ten minutes.", Toast.LENGTH_SHORT).show();
                break;
            case 2:
                Intent service1 = new Intent(context, DoseAlarmService.class);
                service1.putExtra("doseName", doseName);
                context.startService(service1);
                break;
            }
        }
    });
    levelDialog = builder.create();
    levelDialog.show();
}   

我尝试在switch case中使用getApplicationContext而不是context,但这是我得到的确切错误：

The method getApplicationContext() is undefined for the type new DialogInterface.OnClickListener(){}

有关如何前进的任何建议？

编辑：

直到现在,这些都是我尝试过的：

public void onReceive(final Context context, Intent intent)
{
        ctx = context;
    final CharSequence[] items = {" I'm taking the dose now! "," Remind again in ten minutes. "," Ignore for now. "};
    String doseName = intent.getStringExtra("doseName");
    Toast.makeText(ctx, "Take medicine: " + doseName, Toast.LENGTH_LONG).show();

    AlertDialog.Builder builder = new AlertDialog.Builder(ctx.getApplicationContext());
    builder.setTitle("It's time for your medicine.");
    builder.setSingleChoiceItems(items, -1, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
            switch(item)
            {
            case 0:
                Toast.makeText(ctx, "Good.", Toast.LENGTH_SHORT).show();
                break;
            case 1:
                Toast.makeText(ctx, "Reminder set in ten minutes.", Toast.LENGTH_SHORT).show();
                break;
            case 2:
                Intent service1 = new Intent(ctx.getApplicationContext(), DoseAlarmService.class);
                service1.putExtra("doseName", doseName);
                ctx.startService(service1);
                break;
            }
        }
    });
    levelDialog = builder.create();
    levelDialog.show();
}   

另外,我没有使用ctx,而是直接使用了context.getApplicationContext()并进行了检查.它不起作用.

此外,当我注释掉所有有问题的区域并运​​行以验证对话框是否出现时,我得到以下异常：

07-23 13:26:21.316: E/AndroidRuntime(1756): java.lang.RuntimeException: Unable to start receiver com.dosemanager.ui.DoseAlarmReceiever: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application

请帮忙！

解决方法:

嗯,你已经有了你的上下文 – 它是onReceive()的参数.您不需要使用getApplicationContext().

编辑：你不能在switch case中使用context,因为在Receiver类中定义了context并且你试图在onClickListener类中使用它.
我建议这个：

  public class %YOUR_RECEIVER_CLASS% {
       private Context context;
       public onReceive(Context context, ...) {
            this.context = context;
       }
  }

现在你可以在任何地方使用上下文

标签：android-alertdialog,android,android-alarms,broadcastreceiver
来源： https://codeday.me/bug/20190825/1720547.html