重温5 UI开发

public class

TextView

extends View

implements ViewTreeObserver.OnPreDrawListener

java.lang.Object   ↳android.view.View    ↳android.widget.TextViewKnown Direct Subclasses

Button,CheckedTextView,Chronometer,DigitalClock,EditText,TextClock

ButtonRepresents a push-button widget. CheckedTextViewAn extension to TextView that supports the Checkable interface. ChronometerClass that implements a simple timer. DigitalClockThis class was deprecated in API level 17. It is recommended you useTextClock instead. EditTextEditText is a thin veneer over TextView that configures itself to be editable. TextClock

TextClock can display the current date and/or time as a formatted string. 

Known Indirect Subclasses

AutoCompleteTextView,CheckBox,CompoundButton,ExtractEditText,MultiAutoCompleteTextView,RadioButton,Switch,ToggleButton

1、fill_parent与match_parent

Android2.2开始两者相同，2.2之前用fill_parent，官方推荐match_parent。

2、layout_gravity与gravity

2.1）gravity：指定控件中文字的对齐方式。

layout_gravity：指定控件在所在布局中的对齐方式。

LinearLayout中：

orientation：vertical时：layout_gravity水平方向的设置有效：left/right/center_horizontal

orientation:horiaontal时：layout_gravity垂直方向设置有效：top/bottom/center_vertical.  center 都可以用，总有一个方向生效

2.2）想要设置某个控件居底，可以在空间外加一层LinearLayout并设置其gravity为bottom.

<LinearLayout...android:gravity="bottom"...>  <Button....../></LinearLayout>

3、Button点击事件

3.1)XML: 

<Button...android:onClick="onClick"/><!--点击事件的方法名-->

public void onClick(View view){}

3.2) 

 login_btn.setOnClickListener(new OnClickListener(){@Overridepublic void onClick(View view){}}});//匿名类的方式

3.3)

public class MainActivity extends Activity implements onClickListener{     @Override     protected void onCreate(Bundle savedInstanceState){      super.onCreate(savedInstanceState);      Button button = (Button)findViewById(R.id.button);     button.setOnClickListener(this);}  @Override  public void onClick(View view){}}

3.4)

          Button Btn = (Button) findViewById(R.id.button);          Btn2.setOnClickListener(listener);//设置监听          }        Button.OnClickListener listener = new Button.OnClickListener(){//创建监听对象            public void onClick(View v){                    }          };  

4、EditText

当需要输入EditText中的内容过多时，可以指定最大行数，当达到最大行数时文本就会往上滚动。

android:maxLines="2"

5、ProgressBar/AlertDialog/ProgressDialog

 <ProgressBar        android:id="@+id/progressBar"        android:layout_width="wrap_content"        android:layout_height="wrap_content"         /><!-- 可以设置style="?android:attr/progressBarStyleHorizontal"         android:max="100"-->

//AlertDialog/ProgressDialog

@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}@Overridepublic boolean onOptionsItemSelected(MenuItem item) {// Handle action bar item clicks here. The action bar will// automatically handle clicks on the Home/Up button, so long// as you specify a parent activity in AndroidManifest.xml.int id = item.getItemId();switch(id){case R.id.alertDialog: AlertDialog.Builder alertDialog = new AlertDialog.Builder(this); alertDialog.setTitle("Warning"); alertDialog.setMessage("This is a warning"); alertDialog.setPositiveButton("OK", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {// TODO Auto-generated method stub}}); alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {// TODO Auto-generated method stub}}); alertDialog.show(); break;case R.id.progressDialog:ProgressDialog progressDialog = new ProgressDialog(this);progressDialog.setTitle("ProgressDialog");progressDialog.setMessage("loading...");progressDialog.show();break;default:}return super.onOptionsItemSelected(item);}

完整代码在：https://github.com/HiSunny/ComeOnProgressBarAlertDialogProgressDialog.git