-1

每次用户更改输入时，我都会尝试重新计算，因此我使用了 TextWatcher。它会在更改文本时计算应用程序何时启动，当我输入新值时它不会重新计算。有人可以告诉我我做错了什么吗？使用“onTextChanged”是否正确，我是否必须将整个计算放在该过程中，还是只调用变量一和二变量？请忽略微调器。提前致谢。

公共类 AndroidActivity 扩展 Activity 实现 TextWatcher{

  private Spinner spinner1; 

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.pounds);
    addListenerOnSpinnerItemSelection();

    int one = 0;
    int two = 0;



    try{
      EditText one100lbs = (EditText) findViewById(R.id.one100lbs);
      one = Integer.valueOf(one100lbs.getText().toString().trim());
    }
    catch (NumberFormatException e)
    {
      one = -1;
    }

    try{
      EditText tenPounds = (EditText) findViewById(R.id.tenPounds);
      two = Integer.valueOf(tenPounds.getText().toString().trim()); 
    }
    catch (NumberFormatException e)
    {
      two = -1;
    }

    int result = one + two;

    TextView textView = (TextView) findViewById(R.id.editText1);
    textView.setText(String.valueOf(result)); 




}

//create spinner 
public void addListenerOnSpinnerItemSelection() {
    spinner1 = (Spinner) findViewById(R.id.other_spinner);
    spinner1.setOnItemSelectedListener(new CustomOnItemSelectedListener());
  }

@Override
public void afterTextChanged(Editable s) {
    // TODO Auto-generated method stub
}

@Override
public void beforeTextChanged(CharSequence s, int start, int count,
        int after) {    
    // TODO Auto-generated method stub
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
    // TODO Auto-generated method stub

    int one = 0;
    int two = 0;

    try{
      EditText one100lbs = (EditText) findViewById(R.id.one100lbs);
      one = Integer.valueOf(one100lbs.getText().toString().trim());
    }
    catch (NumberFormatException e)
    {
      one = -1;
    }

    try{
      EditText tenPounds = (EditText) findViewById(R.id.tenPounds);
      two = Integer.valueOf(tenPounds.getText().toString().trim()); 
    }
    catch (NumberFormatException e)
    {
      two = -1;
    }

    int result = one + two;

    TextView textView = (TextView) findViewById(R.id.editText1);
    textView.setText(String.valueOf(result)); 
}

}

4

1 回答 1

0

看来您缺少textview与TextWatcher.

你需要做一些类似于绑定textview的事情TextWatcher：

text = (EditText)findViewById(R.id.yourTextField);
text.addTextChangedListener(this);

阅读本教程以获取简单示例。

于 2013-01-15T22:34:22.110 回答