Question

我要做的是用每个键事件更新TextView - 基本上将EditText的内容复制到TextView。出于某种原因，它不起作用。这是代码：

    View.OnKeyListener keyHandler = new OnKeyListener(){

        public boolean onKey(View v, int keyCode, KeyEvent event) {
            TextView id = (TextView)findViewById(R.id.previewEmplIdData);
            TextView fn = (TextView)findViewById(R.id.previewNameData);
            TextView ttl = (TextView)findViewById(R.id.previewTitleData);
            TextView mgr = (TextView)findViewById(R.id.previewMgrData);
            TextView loc = (TextView)findViewById(R.id.previewLocData);
            TextView strt = (TextView)findViewById(R.id.previewStartData);
            String text = "";
            EditText et;
            switch(v.getId()){
            case R.id.etFirstName:
                et = (EditText)v; // must first switch to a text field
                text = et.getText().toString();
                fn.setText(text);
                break;
            case R.id.etLastName:
                et = (EditText)v;
                text = et.getText().toString();
                break;
            case R.id.etEmplId:
                et = (EditText)v;
                text = et.getText().toString();
                id.setText(text);
                break;
            case R.id.etStartDate:
                et = (EditText)v;
                text = et.getText().toString();
                strt.setText(text);
                break;
            case R.id.etTitle:
                et = (EditText)v;
                text = et.getText().toString();
                ttl.setText(text);
                break;
            case R.id.spinnerLocation:
                break;
            case R.id.spinnerManager:
                break;
            }
            return false;
        }
    };

基本上我在按键时切换View ID，然后将视图转换为EditText。我不确定为什么这不起作用...我总是非常不幸的是让switch语句工作。有什么帮助吗？

Answer 1

你在哪里应用keyHandler？如果您刚刚创建并初始化它，但未在任何视图中使用，则根本不会运行。

Answer 2

OnKeyListener不适用于软键盘。您应该实施TextWatcher来跟踪文本更改。另请查看here。

Answer 3

我刚刚使用以下方法解决了同样的问题：

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import android.widget.TextView;

public class InputField extends AppCompatActivity {

private EditText input;
private TextView displayString;
private String writeText;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_input_field);

    input = (EditText) findViewById(R.id.editText);
    displayString = (TextView) findViewById(R.id.displayStringText);

    input.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {}

        @Override
        public void afterTextChanged(Editable s) {
            writeText = input.getText().toString();
            displayString.setText(writeText);
        }
    });

  }
}

每次按键更新TextView

3 个答案: