Android 自定義TopBar的複用

自定義TopBar的複用

       從來沒發過關於android的技術文檔，其實自己最近一個月都在學習java，但是感覺學java不學界面編程，沒啥意思，所以傻傻的學了下AWT編程，結果發現這什麼玩意啊，浪費青春，現在哪還有用java做pc端的呀，不說廢話，趕緊學習android，不然這個月又白忙活了。

       其實這個自定義TopBar呢，以前考覈的時候基本上沒時間去弄，因爲要寫很多屬性，相信你看下面的一堆堆看似重複的代碼會一臉懵X，其實也就是左按鈕，標題，右按鈕的屬性設置，什麼大小啊，字體顏色啊，字體大小啊，背景啊，統統都得寫，所以才叫的上“自定義”嘛。我做得這麼難看，相信你做得比我好。

• /res/values/attrs.xml

  • <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <declare-styleable name="TopBar">
            <attr name="titleText" format="string"/>
            <attr name="titleSize" format="dimension"/>
            <attr name="titleColor" format="color"/>
    
            <attr name="leftTextColor" format="color"/>
            <attr name="leftBackground" format="reference|color"/>
            <attr name="leftText" format="string"/>
    
            <attr name="rightTextColor" format="color"/>
            <attr name="rightBackground" format="reference|color"/>
            <attr name="rightText" format="string"/>
        </declare-styleable>

    </resources>

    
    
  • <declare-styleable>：聲明使用自定義屬性，並通過name屬性來確定引用的名稱
    <attr>：聲明具體的自定義屬性，標題文字字體、大小、顏色、背景
    
    fomat：屬性來指定屬性的類型，多種屬性可用”|“分隔開

• XML文件

  • <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"        //這個表示下面可以用app開頭，命名空間
        android:layout_width="match_parent"
        android:orientation="vertical"
        android:layout_height="match_parent"
        >
        <com.android.rdc.view.TopBar
            android:id="@+id/topbar"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            app:leftText="返回"
            app:leftBackground="@color/colorPrimaryDark"
            app:leftTextColor="@color/colorAccent"
            app:rightText="下一步"
            app:rightTextColor="@color/colorAccent"
            app:rightBackground="@color/colorPrimaryDark"
            app:titleText="TopBar"
            app:titleColor="@color/colorAccent"
            app:titleSize="13sp"
            >
        </com.android.rdc.view.TopBar>
    </LinearLayout>

• TopBar的代碼實現

  • public class TopBar extends RelativeLayout {
       private int mLeftTextColor;
       private Drawable mLeftBackground;
       private String mLeftText;
       private int mRightTextColor;
       private Drawable mRightBackground;
       private String mRightText;
       private String mTitleText;
       private int mTitleColor;
       private float mTitleSize;
       private Button leftBtn;
       private LayoutParams leftParams;
       private Button rightBtn;
       private LayoutParams rightParams;
       private LayoutParams titleParams;
       private TopBarListener listener;
    
       public interface TopBarListener {        //接口對象，實現回調機制，不考慮實現
          public void leftClick();
          public void rightClick();
       }
       public void setListener(TopBarListener topBarListener) {
          this.listener = topBarListener;
       }
    
       public TopBar(Context context, AttributeSet attrs) {
          super(context, attrs);
    
          //系統提供了TypedArray數據結構來獲取自定義屬性集    
          TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.TopBar);
          mLeftTextColor = ta.getColor(R.styleable.TopBar_leftTextColor, 0);
          mLeftBackground = ta.getDrawable(R.styleable.TopBar_leftBackground);
          mLeftText = ta.getString(R.styleable.TopBar_leftText);
          mRightTextColor = ta.getColor(R.styleable.TopBar_rightTextColor, 0);
          mRightBackground = ta.getDrawable(R.styleable.TopBar_rightBackground);
          mRightText = ta.getString(R.styleable.TopBar_rightText);
          mTitleColor = ta.getColor(R.styleable.TopBar_titleColor, 0);
          mTitleSize = ta.getDimension(R.styleable.TopBar_titleSize, 10);
          mTitleText = ta.getString(R.styleable.TopBar_titleText);
    
          ta.recycle();             //當獲取完所有的屬性值後，要使用recycle()來完成資源的回收
          leftBtn = new Button(context);
          leftBtn.setText(mLeftText);
          leftBtn.setTextColor(mLeftTextColor);
          leftBtn.setBackground(mLeftBackground);
          leftParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
          leftParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
          addView(leftBtn, leftParams);
          rightBtn = new Button(context);
          rightBtn.setText(mRightText);
          rightBtn.setTextColor(mRightTextColor);
          rightBtn.setBackground(mRightBackground);
          rightParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
          rightParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
          addView(rightBtn, rightParams);
          TextView tvTitle = new TextView(context);
          tvTitle.setText(mTitleText);
          tvTitle.setTextColor(mTitleColor);
          tvTitle.setTextSize(mTitleSize);
          tvTitle.setGravity(Gravity.CENTER);
          titleParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
          titleParams.addRule(RelativeLayout.CENTER_IN_PARENT);
          addView(tvTitle, titleParams);
          leftBtn.setOnClickListener(new OnClickListener() {    //按鈕的點擊事件
             @Override
             public void onClick(View view) {
                listener.leftClick();
             }
          });
    
          rightBtn.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View view) {
                listener.rightClick();
             }
          });
       }
    }

• MainActivity

  • public class MainActivity extends AppCompatActivity {
    
       @Override
       protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          requestWindowFeature(Window.FEATURE_NO_TITLE);
          setContentView(R.layout.activity_main);
          TopBar topBar = (TopBar) findViewById(R.id.topbar);
          topBar.setListener(new TopBar.TopBarListener() {             //回調機制，實現按鈕的點擊
             @Override
             public void leftClick() {
                Toast.makeText(MainActivity.this, "left", Toast.LENGTH_SHORT).show();
             }
    
             @Override
             public void rightClick() {
                Toast.makeText(MainActivity.this, "right", Toast.LENGTH_SHORT).show();
             }
          });
       }
    

• 後續的亂入
  • 通過include加入到其他佈局
  • <include layout="@layout/topbar"/>