public class LockActivity   extends Activity{	@Override	protected void onCreate(Bundle savedInstanceState) {		// TODO Auto-generated method stub		super.onCreate(savedInstanceState);		setContentView(R.layout.lockscreen);		initUI();			}	public  EditText editText,editText2,editText3,editText4;	private void initUI(){			editText  = (EditText) findViewById(R.id.editText1);		editText2  = (EditText) findViewById(R.id.editText2);		editText3  = (EditText) findViewById(R.id.editText3);		editText4  = (EditText) findViewById(R.id.editText4);		editText.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				String resString =editText.getText().toString().trim();				if (resString!=null && resString.length()>0) {					editText2.requestFocus();									}			}		});		editText2.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				String resString =editText2.getText().toString().trim();				if (resString!=null && resString.length()>0) {					editText3.requestFocus();									}			}		});	editText3.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			String resString =editText3.getText().toString().trim();			if (resString!=null && resString.length()>0) {				editText4.requestFocus();							}		}	});	editText4.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			String resString =editText4.getText().toString().trim();			if (resString!=null && resString.length()>0) {				//隐藏键盘											InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);		imm.hideSoftInputFromWindow(editText4.getWindowToken(), 0); //强制隐藏键盘  			}		}	});	}	}

布局如下:

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:gravity="center_vertical" >    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"         android:orientation="horizontal"        android:paddingRight="20dp">        <EditText        android:id="@+id/editText1"        android:layout_width="fill_parent"        android:layout_weight="1"        android:layout_marginLeft="20dp"                android:layout_height="wrap_content"       	android:singleLine="true"        android:ems="1"        android:inputType="textPassword" >    </EditText>    <EditText        android:id="@+id/editText2"         android:layout_width="fill_parent"        android:layout_weight="1"        android:layout_marginLeft="20dp"        android:layout_height="wrap_content"       	android:singleLine="true"        android:ems="1"        android:inputType="textPassword" >    </EditText>    <EditText        android:id="@+id/editText3"        android:layout_width="fill_parent"        android:layout_weight="1"        android:layout_marginLeft="20dp"        android:layout_height="wrap_content"        	android:singleLine="true"        android:ems="1"        android:inputType="textPassword" >    </EditText>    <EditText        android:id="@+id/editText4"        android:layout_width="fill_parent"        android:layout_weight="1"        android:layout_marginLeft="20dp"        android:layout_height="wrap_content"       	android:singleLine="true"        android:ems="1"        android:inputType="textPassword" >    </EditText>    </LinearLayout></RelativeLayout>

仿苹果锁屏实现