Question

我有一个扩展Activity的类，当我尝试从onCreate（）方法访问上下文时，它会被打印但是当我将它保存在变量上下文中并尝试从committext()函数访问它时如下所示，它打印为null。我也试过用＃34;这个＆＃34;和getBaseContext()直接来自committext()函数，因为它是同一个类的一部分，我得到空指针异常。请帮我弄清楚出了什么问题。

public class MainKeyboardActionListener  extends Activity implements KeyboardView.OnKeyboardActionListener, View.OnTouchListener {
    private Context context;
    public static boolean active = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mode_keyboard, false);
        context=getBaseContext();
        System.out.println("contexxtt1"+context);
    }

    @Override
    public void onStart() {
        super.onStart();    
        active = true;
    }

    @Override
    protected void onResume() {
        super.onResume();
    }

    private static class myHandler extends Handler {
    }
    ;

    public void setInputConnection(InputConnection ic) {    
    }

    @Override
    public void onKey(int arg0, int[] arg1) {
        // TODO Auto-generated method stub    
    }

    @Override
    public void onPress(int keyCode) {
    }

    @Override
    public void onRelease(int keyCode) {
        commitText(String.valueOf(keyCode));
    }

    private void handleException(int keyCode) {
    }

    private void removeHalantMode() {
    }


    private void commitText(String text) {
        if(active==true) {
            System.out.println("contexxtt"+context);
        }
    }

    @Override
    public void onText(CharSequence arg0) {
        // TODO Auto-generated method stub
    }

    @Override
    public void swipeDown() {
        // TODO Auto-generated method stub
    }

    @Override
    public void swipeLeft() {
        // TODO Auto-generated method stub
    }

    @Override
    public void swipeRight() {
        // TODO Auto-generated method stub
    }

    @Override
    public void swipeUp() {
        // TODO Auto-generated method stub
    }

    @Override
    protected void onPause() {
        super.onPause();
    }

    @Override
    public void onStop() {
        super.onStop();
        active = false;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();    
    }
}

Answer 1

让myHandler课程不是static。

如何从在android中扩展Activity的类的函数中获取上下文？

1 个答案: