安卓：访问一个onClickListener内的全局变量 [英] Android: Accessing a global Variable inside an onClickListener

问题描述

因此​​，在Android的/ Java的，我需要访问一个全局变量，它是一个的EditText [] 我创建上面的的onCreate 的内我的活动的方法 onClickListener 。下面是变量：

 公共类NCDTC prelayActivity延伸活动{
     最终的EditText [] = relayLabelEdits新的EditText [N];
 

其中， N 是另外一个全局变量整数。

我的问题是，为了访问这些的EditText 内的 onclickListener 我不得不做出最后的访问内在onClickListener，但我需要分配 relayLabelEdits 来一个新的的EditText [] 如果对N的值发生变化，它是惯于做的。

下面是 onClickListener （应用程序的主要部分是打开通过WiFi TCP套接字和控制继电器等等忽略接口的信息以及System.out的。的println点到 relayLabelEdits 返回NULL，除非 relayLabelEdits 变量是决赛）：

 按钮保存=新按钮（本）;
    save.setOnClickListener（新View.OnClickListener（）{
        @覆盖
        公共无效的onClick（视图v）{
            的EditText [] = saveTargets relayLabelEdits;
            的System.out.println（直接：+ relayLabelEdits [0]）;
            的System.out.println（第一次尝试+ saveTargets [0]）;            //创建一个字符串动态创建的数据库名称
            串relayToSave;            INT myNum的= 0;
            尝试{
                myNum的=的Integer.parseInt（portEditText.getText（）的toString（））;
            }赶上（NumberFormatException的NFE）{
                吐司面包= Toast.makeText（getBaseContext（），您输入只能包含数字端口号，Toast.LENGTH_LONG）;
                toast.show（）;
                返回;
            }
            的System.out.println（ipAEditText.getText（）的toString（））;
            cPanel.saveString（IPA，ipAEditText.getText（）的toString（））;
            cPanel.saveInt（端口中，myNum）;            的for（int i = 0; I＆LT; N;我++）{
                relayToSave =接力+（I + 1）;
                的System.out.println（我在这里）;
                的System.out.println（relayLabelEdits [I]）;
                cPanel.saveString（relayToSave，relayLabelEdits [I] .getText（）的toString（））;
                //cPanel.saveString(relayToSave，它的工作）;
                的System.out.println（我在这里）;
            }            如果（cPanel.connect（）==真）{
                createMainContainer（）;
                的setContentView（sView）;
                getRelayNames（）;
                displayRelayNames（）;
                updateButtonText（）;
            }
            其他{
                吐司面包= Toast.makeText（getBaseContext（），无法连接，检查IP地址和端口号，Toast.LENGTH_LONG）;
                toast.show（）;
            }
        }
    }）;
 

所以，我如何可以访问任何想法的EditText [] 中的 onClickListener 没有使它最终<？ / p>

解决方案

你为什么不使听者类外活动引用传递给它？

So in Android/Java, I need to access a global variable that is an EditText[]that I create above the onCreate method of my activity inside of an onClickListener. Here is the variable:

public class NCDTCPRelayActivity extends Activity {
     final EditText[] relayLabelEdits = new EditText[n];

Where n is another global variable integer.

My problem is that in order to access these EditText inside an onclickListener i had to make final to access inside the onClickListener, but I need to assign relayLabelEdits to a new EditText[] if the value of n changes which it is wont to do.

Below is the onClickListener (the main portion of the app is to open a tcp socket and control relays via WiFi so just ignore the socket information and those System.out.println that point to the relayLabelEdits return null unless the relayLabelEdits variable is final):

    Button save = new Button(this);
    save.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            EditText[] saveTargets = relayLabelEdits;
            System.out.println("Direct: " + relayLabelEdits[0]);
            System.out.println("first try " + saveTargets[0]);



            //Creates string to create the database names on the fly
            String relayToSave;

            int myNum = 0;
            try {
                myNum = Integer.parseInt(portEditText.getText().toString());
            } catch(NumberFormatException nfe) {
                Toast toast = Toast.makeText(getBaseContext(), "The Port Number you entered must only contain numbers", Toast.LENGTH_LONG);
                toast.show();
                return;
            }
            System.out.println(ipAEditText.getText().toString());
            cPanel.saveString("ipA", ipAEditText.getText().toString());
            cPanel.saveInt("port", myNum);

            for (int i = 0; i < n; i++) {
                relayToSave = "relay" + (i+1);
                System.out.println("HERE I AM");
                System.out.println(relayLabelEdits[i]);
                cPanel.saveString(relayToSave, relayLabelEdits[i].getText().toString());
                //cPanel.saveString(relayToSave, "It worked");
                System.out.println("HERE I AM");
            }

            if (cPanel.connect() == true){
                createMainContainer();
                setContentView(sView);
                getRelayNames();
                displayRelayNames();
                updateButtonText();
            }
            else {
                Toast toast = Toast.makeText(getBaseContext(), "Could Not Connect, check IP address and Port Number", Toast.LENGTH_LONG);
                toast.show();
            }
        }
    });

So any ideas on how I can access the EditText[] inside the onClickListener without making it final?

解决方案

Why don't you make the listener a class outside and pass the activity reference to it?

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