Question

我想使用Firebase在ChatListAdapter类的mainActivity中弹出警报视图。

问题/错误：

com.firebase.androidchat.Main.activity.this无法从静态上下文中引用

ChatListAdapter中的代码：

public class ChatListAdapter extends FirebaseListAdapter<Chat> {

...

protected void populateView(View view, Chat chat) {
...    
    MainActivity.displayAmountPopup();
}

ChatListAdapter中的代码：

public static void displayAmountPopup(){

....

    new AlertDialog.Builder(MainActivity.this)
            .setTitle(strTitle)
            .setMessage(strAmountMessage)
            .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Log.d("AlertDialog", "Positive");
                    // Present Acknowledgement View!!!!!!!!!
                    Intent intent = new Intent(MainActivity.this, AcknowledgementActivity.class);
                    startActivity(intent);

                    /*Couldn't work this Error:local variable mContext is accessed from within inner class; needs to be declared final
                    Intent intent = new Intent(mContext, AcknowledgementActivity.class);
                    //startActivity(intent);
                    mContext.startActivity(new Intent(mContext, AcknowledgementActivity.class));*/
                }
            })
            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Log.d("AlertDialog", "Negative");
                }
            })
            .show();
}

Answer 1

com.firebase.androidchat.Main.activity.this无法从静态上下文中引用

因为无法从MainActivity.this方法/块访问static。

要获取显示AlertDialog的上下文，请向displayAmountPopup方法添加一个Context参数：

public static void displayAmountPopup(Context mContext){
....
    new AlertDialog.Builder(mContext)
    ....
}

现在，在从displayAmountPopup调用时，将上下文传递给populateView方法：

MainActivity.displayAmountPopup(view.getContext());

Answer 2

您可以在对话框中使用上下文和强制转换活动以启动Intent

Intent intent = new Intent(context, AcknowledgementActivity.class);
((Activity) context).startActivity(intent)

来自评论代码

public static void displayAmountPopup(Context context){

....

    new AlertDialog.Builder(context)
            .setTitle(strTitle)
            .setMessage(strAmountMessage)
            .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Log.d("AlertDialog", "Positive");
                    // Present Acknowledgement View
                    //Intent intent = new Intent(context, AcknowledgementActivity.class);
                    //startActivity(intent);
                }
            })
            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Log.d("AlertDialog", "Negative");
                }
            })
            .show();
}

如何从自定义FirebaseListAdapter类调用mainActivity中的静态方法？

2 个答案: