单击退格键时，Android 如何聚焦另一个编辑文本

Question

我试图让 Pin 进入页面，我创建了 4 个 EditTexts，我在我的活动中创建了一个函数。我的问题是当我单击退格按钮时，我想将 Current EditText 聚焦到 Before(Back) EditText 但 Key listener 不起作用。

逻辑很简单，当用户输入一个数字来编辑文本时，它会失去焦点，而下一个编辑文本正在获得焦点，然后就这样了。但问题是当我单击后退空格时，我想在 edittext 之前返回以再次输入数字。我试图在 beforeTextChange 中插入 keyListener 但它不起作用。

 private void SetTextChange(final EditText etCurrent, final EditText etForward,final EditText etBack, final boolean isLast, final int currentPosition)
{

    etCurrent.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) {

            if (etCurrent.getText().length() == 1 && !isLast ) {
                etCurrent.setTypeface(null, Typeface.NORMAL);
                etCurrent.clearFocus();
                etForward.requestFocus();
                etForward.setCursorVisible(true);

                etCurrent.getBackground().setColorFilter(getResources().getColor(R.color.lavender_indigo), PorterDuff.Mode.SRC_ATOP);
            } else if (etCurrent.length() == 0) {
                etCurrent.getBackground().setColorFilter(getResources().getColor(R.color.french_gray), PorterDuff.Mode.SRC_ATOP);
                etCurrent.setTypeface(null, Typeface.SANS_SERIF.getStyle());

                etCurrent.setTypeface(null, Typeface.NORMAL);
                etCurrent.clearFocus();
                etBack.requestFocus();
                etBack.setCursorVisible(true);

            }


            if (etCurrent.length() != 0) {
                Integer currentKey = Integer.parseInt(etCurrent.getText().toString());
                keyList.set(currentPosition, currentKey);
            } else
                keyList.set(currentPosition, -1);

            if (keyList.size() > 3)
                showToast(keyList.get(0) + " " + keyList.get(1) + " " + keyList.get(2) + " " + keyList.get(3));

        }

        @Override
        public void afterTextChanged(Editable s) {

        }
    });

    /*curText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
        public void onFocusChange(View arg0, boolean arg1) {
            curText = etCurrent;
            backText = etBack;
            curText.setText("");
        }

        });*/
    }

这也是我的EditText示例xml之一。（其他都一样）

  <EditText
        android:layout_column="1"
        android:layout_columnWeight="1"
        android:id="@+id/etActivationDigit1"
        android:layout_width="70dp"
        android:layout_height="wrap_content"
        android:textSize="80dp"
        android:textAlignment="center"
        android:gravity="center_horizontal"
        android:hint="*"
        android:textColorHint="@color/french_gray"
        android:backgroundTint="@color/french_gray"
        android:fontFamily="sans-serif"
        android:textColor="@color/perfume"
        android:maxLength="1"
        android:inputType="number"
         />

当用户输入错误的数字时，我只想擦除并重新聚焦。注意：当您填写所有字段时，您会看到您可以删除并返回，但我想返回密码中间。谢谢你。

  etCurrent.setOnKeyListener(new View.OnKeyListener() {
        @Override
        public boolean onKey(View v, int keyCode, KeyEvent event) {

            if(etCurrent.getText().toString() == "" && keyCode == event.KEYCODE_DEL)
            {
                etCurrent.setText("");
                etCurrent.clearFocus();
                etBack.requestFocus();
                etBack.setText("");
            }
            return false;
        }
    });

当我触摸退格键时，我的退格键侦听器不会触发，但会触发所有其他字符。

Answer 1

看看这个。
MainActivity.java

    public class MainActivity extends Activity {

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

        final EditText one = (EditText) findViewById(R.id.edtOne);
        final EditText two = (EditText) findViewById(R.id.edtTwo);
        final EditText three = (EditText) findViewById(R.id.edtThree);
        final EditText four = (EditText) findViewById(R.id.edtFour);

        one.addTextChangedListener(new TextWatcher() {

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

            }
        });
        two.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                if(s.toString().trim().length() == 0){
                    one.requestFocus();
                    one.setSelection(one.getText().toString().length());
                }

            }

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

            }

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

            }
        });
        three.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                if(s.toString().trim().length() == 0){
                    two.requestFocus();
                    two.setSelection(two.getText().toString().length());
                }

            }

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

            }

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

            }
        });
        four.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                if(s.toString().trim().length() == 0){
                    three.requestFocus();
                    three.setSelection(three.getText().toString().length());
                }

            }

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

            }

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

            }
        });


    }


}

// 使用此代码作为参考。

customDialog.setOnKeyListener(new OnKeyListener() {

            @Override
            public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent event) {

                if (event.getAction() != KeyEvent.ACTION_DOWN) {
                    if (keyCode == KeyEvent.KEYCODE_BACK) {
                        customDialog.dismiss();
                        HomeActivity.this.finish();
                    } else if (keyCode == KeyEvent.KEYCODE_DEL) {
                        if (!pin3.getText().toString().equals("")) {
                            pin3.setText("");
                            pin3.requestFocus();
                        } else if (!pin2.getText().toString().equals("")) {
                            pin2.setText("");
                            pin2.requestFocus();
                        } else if (!pin1.getText().toString().equals("")) {
                            pin1.setText("");
                            pin1.requestFocus();
                        }
                    }
                }
                return true;
            }
        });
        return customDialog;

我在我的应用程序中使用此代码并且它完全可以工作。

活动主文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <EditText
        android:id="@+id/edtOne"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:text="0" />
    <EditText
        android:id="@+id/edtTwo"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:text="2" />
    <EditText
        android:id="@+id/edtThree"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:text="3" />
    <EditText
        android:id="@+id/edtFour"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:text="4" />

</LinearLayout>