Android中BaseActivity的簡單使用,可以切換無數據、網絡錯誤的界面

        一般來說，項目中都會有多個Activity或者Fragment,每個界面都會有一些相同的地方，比如標題欄、無數據界面、網絡錯誤界面，每個界面都寫就會顯得很重複，也不便於維護。所以這個時候就有必要寫一個基類來進行封裝，也就是BaseActivity或者BaseFragment

先看一下效果

  

無數據和網絡錯誤的情況。對於上邊的標題欄，可能有多種情況，有標題欄，無標題欄，是否有返回按鈕，右邊是否顯示文字或圖片。這些情況我們都可以寫在基類中。這些公用的界面都是寫在BaseActivity的對應的xml文件中。

activity_base.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_base_root"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    android:orientation="vertical"
   >

    <include
        android:id="@+id/activity_base_title_bar"
        layout="@layout/title_bar" />

    <include
        android:id="@+id/activity_base_state_layout"
        android:visibility="gone"
        layout="@layout/state_layout"/>

</LinearLayout>

裏面用include添加進兩個佈局title_bar就是標題欄，state_layout是無數據和無網絡的佈局。

title_bar.xml

<RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="@dimen/x100"
        android:background="@color/colorPrimaryDark">

        <TextView
            android:id="@+id/title_bart_tv_left"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:text="返回"
            android:drawableLeft="@drawable/icon_back_small"
            android:drawablePadding="@dimen/x6"
            android:textColor="@color/colorBlack"
            android:layout_marginLeft="@dimen/x20"
            android:textStyle="bold"
            android:textSize="@dimen/bigOneSize" />

        <TextView
            android:id="@+id/title_bart_tv_middle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:layout_marginLeft="@dimen/x20"
            android:text=""
            android:textColor="@color/colorBlack"
            android:textSize="@dimen/bigTwoSize"
            android:textStyle="bold" />

        <TextView
            android:id="@+id/title_bart_tv_right"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_marginRight="@dimen/x20"
            android:layout_centerVertical="true"
            android:text=""/>

    </RelativeLayout>

state_layout.xml

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

    <LinearLayout
        android:id="@+id/state_layout_error"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:orientation="vertical"
        android:visibility="gone">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@drawable/ic_error" />

        <Button
            android:id="@+id/state_layout_error_bt"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="@null"
            android:text="網絡異常，點擊重新加載"
            android:textColor="@drawable/text_primary_light_selector" />
    </LinearLayout>
    
    <LinearLayout
        android:id="@+id/state_layout_empty"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:orientation="vertical"
        android:visibility="gone">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@drawable/ic_empty" />

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="@null"
            android:text="暫無數據"
            android:textColor="@color/colorGrayText" />
    </LinearLayout>
</RelativeLayout>

兩個佈局就不多說了，主要看BaseActivity的代碼

public class BaseActivity extends AppCompatActivity {

    LinearLayout mRootBaseView;//根佈局
    View titleView;//include的titleBar
    TextView tvLeft;//titleBar左邊的返回鍵
    TextView tvMiddle;//titleBar的標題

    View mStateLayout;//include的state_layout
    LinearLayout ll_page_state_error;//stateLayout網絡錯誤的佈局
    LinearLayout ll_page_state_empty;//stateLayout無數據的佈局
    Button btReload;//網絡錯誤重新加載的佈局

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        super.setContentView(R.layout.activity_base);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            getWindow().getDecorView()
                    .setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                            | View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR);
        }

        initBaseView();

        /*//5.0以下設置狀態欄顏色
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
            new SystemStatusManager(this).setTranslucentStatus(R.color.colorPrimaryDark);
            getWindow().getDecorView()
                    .setSystemUiVisibility( View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                            |View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR);
        }*/
    }


    //這裏控件初始化沒用ButterKnife 會報錯  原因暫時沒找到
    public void initBaseView() {
        mRootBaseView = (LinearLayout) findViewById(R.id.activity_base_root);
        titleView = findViewById(R.id.activity_base_title_bar);
        tvLeft = (TextView) findViewById(R.id.title_bart_tv_left);
        tvMiddle = (TextView) findViewById(R.id.title_bart_tv_middle);
        mStateLayout = findViewById(R.id.activity_base_state_layout);
        btReload = (Button) findViewById(R.id.state_layout_error_bt);
        ll_page_state_empty = (LinearLayout) findViewById(R.id.state_layout_empty);
        ll_page_state_error = (LinearLayout) findViewById(R.id.state_layout_error);
    }


    /**
     * 必須重寫setContentView注意不能夠添加這行代碼 目的將當前界面的佈局添加到BaseActivity中去
     * super.setContentView(R.layout.activity_base);
     */
    @Override
    public void setContentView(int layoutResID) {
        View view = getLayoutInflater().inflate(layoutResID, null);
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
        if (null != mRootBaseView) {
            mRootBaseView.addView(view, lp);
        }
    }

    /**
     *
     * @param titleBarIsShow titleBar是否顯示
     * @param tvLeftIsShow 返回鍵是否顯示
     * @param middleText 中間的文字
     */
    public void initTitleBar(boolean titleBarIsShow, boolean tvLeftIsShow,
                             String middleText) {
        if (titleBarIsShow == true) {
            if (!tvLeftIsShow) {
                tvLeft.setVisibility(View.GONE);
            } else {
                tvLeft.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        finish();
                    }
                });
            }
            tvMiddle.setText(middleText);
        } else {
            titleView.setVisibility(View.GONE);
        }
    }

    /**
     * 切換頁面的佈局
     * @param pageState 頁面狀態 NORMAL  EMPTY  ERROR
     */
    public void changePageState(PageState pageState) {
        switch (pageState) {
            case NORMAL:
                if (mStateLayout.getVisibility() == View.VISIBLE) {
                    mStateLayout.setVisibility(View.GONE);
                }
                break;
            case ERROR:
                if (mStateLayout.getVisibility() == View.GONE) {
                    mStateLayout.setVisibility(View.VISIBLE);
                    ll_page_state_error.setVisibility(View.VISIBLE);
                    btReload.setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View view) {
                            reloadInterface.reloadClickListener();
                        }
                    });
                    ll_page_state_empty.setVisibility(View.GONE);
                }
                break;
            case EMPTY:
                if (mStateLayout.getVisibility() == View.GONE) {
                    mStateLayout.setVisibility(View.VISIBLE);
                    ll_page_state_error.setVisibility(View.GONE);
                    ll_page_state_empty.setVisibility(View.VISIBLE);
                }
                break;
        }


    }


    //網絡錯誤重新加載的接口
    public ReloadInterface reloadInterface;

    public void setReloadInterface(ReloadInterface reloadInterface) {
        this.reloadInterface = reloadInterface;
    }

    public interface ReloadInterface {
        void reloadClickListener();
    }

    public enum PageState {
        /**
         * 數據內容顯示正常
         */
        NORMAL,
        /**
         * 數據爲空
         */
        EMPTY,
        /**
         * 數據加載失敗
         */
        ERROR
    }

}

在MyMessageActivity繼承BaseActivity並實現ReloadInterface接口,如果該界面沒有用到則不用實現此接口

public class MyMessageActivity extends BaseActivity implements ReloadInterface {  
@Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_my_message);//重載BaseActivity的setContentView方法   
        initTitleBar(true, true, "我的消息");  
        setReloadInterface(this);  
    }  
 @Override  
    public void reloadClickListener() {  
        //You want to do  
    }  
}  

對於佈局的切換，主要是在網絡請求裏調用，比如OkHttp在請求失敗的時候調用changePageState(PageState.Error);

okHttpHelper.post(Constants.HTTP.BaseUrl, params, new ProgressDialogCallBack<MessageEntity>(context) {

            @Override
            public void onFailure(Request request, IOException e) {
                changePageState(PageState.ERROR);//切換成網絡異常佈局
            }

            @Override
            public void onSuccess(Response response, MessageEntity messageEntity) {              
                    List<List> messageList = messageEntity.getMsg().getRows();
                    if (messageList.size() == 0) {//數據爲空顯示無數據
                        changePageState(PageState.EMPTY);
                    }else{//數據不爲空正常顯示
                        changePageState(PageState.NORMAL);
                    }                              
            }
});

如果後期項目需要，還會繼續更新BaseActivity。

明天就是端午節了，大家端午節快樂！