Android实现加载状态视图切换效果

关于Android加载状态视图切换，具体内容如下

1.关于Android界面切换状态的介绍

怎样切换界面状态？有些界面想定制自定义状态？状态如何添加点击事件？下面就为解决这些问题！
内容界面
加载数据中
加载数据错误
加载后没有数据
没有网络

2.思路转变，抽取分离类管理几种状态

以前做法：

直接把这些界面include到main界面中，然后动态去切换界面，后来发现这样处理不容易复用到其他项目中，而且在activity中处理这些状态的显示和隐藏比较乱
利用子类继承父类特性，在父类中写切换状态，但有些界面如果没有继承父类，又该如何处理

现在做法：

让View状态的切换和Activity彻底分离开，必须把这些状态View都封装到一个管理类中，然后暴露出几个方法来实现View之间的切换。
在不同的项目中可以需要的View也不一样，所以考虑把管理类设计成builder模式来自由的添加需要的状态View

3.关于该状态切换工具优点分析

可以自由切换内容，空数据，异常错误，加载，网络错误等5种状态
父类BaseActivity直接暴露5中状态，方便子类统一管理状态切换

/**
* ================================================
* 作  者：杨充
* 版  本：1.0
* 创建日期：2017/7/6
* 描  述：抽取类
* 修订历史：
* ================================================
*/
public abstract class BaseActivity extends AppCompatActivity {

  protected StatusLayoutManager statusLayoutManager;

  @Override
  protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_base_view);
    initStatusLayout();
    initBaseView();
    initToolBar();
    initView();
  }

  protected abstract void initStatusLayout();

  protected abstract void initView();

  /**
  * 获取到布局
  */
  private void initBaseView() {
    LinearLayout ll_main = (LinearLayout) findViewById(R.id.ll_main);
    ll_main.addView(statusLayoutManager.getRootLayout());
  }

  //正常展示数据状态
  protected void showContent() {
    statusLayoutManager.showContent();
  }

  //加载数据为空时状态
  protected void showEmptyData() {
    statusLayoutManager.showEmptyData();
  }

  //加载数据错误时状态
  protected void showError() {
    statusLayoutManager.showError();
  }

  //网络错误时状态
  protected void showNetWorkError() {
    statusLayoutManager.showNetWorkError();
  }

  //正在加载中状态
  protected void showLoading() {
    statusLayoutManager.showLoading();
  }
}

当状态是加载数据失败时，点击可以刷新数据；当状态是无网络时，点击可以设置网络

/**
* 点击重新刷新
*/
private void initErrorDataView() {
  statusLayoutManager.showError();
  LinearLayout ll_error_data = (LinearLayout) findViewById(R.id.ll_error_data);
  ll_error_data.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
      initData();
      adapter.notifyDataSetChanged();
      showContent();
    }
  });
}

/**
* 点击设置网络
*/
private void initSettingNetwork() {
  statusLayoutManager.showNetWorkError();
  LinearLayout ll_set_network = (LinearLayout) findViewById(R.id.ll_set_network);
  ll_set_network.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
      Intent intent = new Intent("android.settings.WIRELESS_SETTINGS");
      startActivity(intent);
    }
  });
}

倘若有些页面想定制状态布局，也可以自由实现，很简单：

/**
* 自定义加载数据为空时的状态布局
*/
private void initEmptyDataView() {
  statusLayoutManager.showEmptyData();
  //此处是自己定义的状态布局
  **statusLayoutManager.showLayoutEmptyData(R.layout.activity_emptydata);**
  LinearLayout ll_empty_data = (LinearLayout) findViewById(R.id.ll_empty_data);
  ll_empty_data.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
      initData();
      adapter.notifyDataSetChanged();
      showContent();
    }
  });
}

4.如何实现的步骤

1）.先看看状态管理器类【builder建造者模式】

loadingLayoutResId和contentLayoutResId代表等待加载和显示内容的xml文件
几种异常状态要用ViewStub，因为在界面状态切换中loading和内容View都是一直需要加载显示的，但是其他的3个只有在没数据或者网络异常的情况下才会加载显示，所以用ViewStub来加载他们可以提高性能。

public class StateLayoutManager {

  final Context context;
  final ViewStub netWorkErrorVs;
  final int netWorkErrorRetryViewId;
  final ViewStub emptyDataVs;
  final int emptyDataRetryViewId;
  final ViewStub errorVs;
  final int errorRetryViewId;
  final int loadingLayoutResId;
  final int contentLayoutResId;
  final int retryViewId;
  final int emptyDataIconImageId;
  final int emptyDataTextTipId;
  final int errorIconImageId;
  final int errorTextTipId;
  final VLayout errorLayout;
  final VLayout emptyDataLayout;

  final RootFrameLayout rootFrameLayout;
  final OnShowHideViewListener onShowHideViewListener;
  final OnRetryListener onRetryListener;

  public StateLayoutManager(Builder builder) {
    this.context = builder.context;
    this.loadingLayoutResId = builder.loadingLayoutResId;
    this.netWorkErrorVs = builder.netWorkErrorVs;
    this.netWorkErrorRetryViewId = builder.netWorkErrorRetryViewId;
    this.emptyDataVs = builder.emptyDataVs;
    this.emptyDataRetryViewId = builder.emptyDataRetryViewId;
    this.errorVs = builder.errorVs;
    this.errorRetryViewId = builder.errorRetryViewId;
    this.contentLayoutResId = builder.contentLayoutResId;
    this.onShowHideViewListener = builder.onShowHideViewListener;
    this.retryViewId = builder.retryViewId;
    this.onRetryListener = builder.onRetryListener;
    this.emptyDataIconImageId = builder.emptyDataIconImageId;
    this.emptyDataTextTipId = builder.emptyDataTextTipId;
    this.errorIconImageId = builder.errorIconImageId;
    this.errorTextTipId = builder.errorTextTipId;
    this.errorLayout = builder.errorLayout;
    this.emptyDataLayout = builder.emptyDataLayout;

    rootFrameLayout = new RootFrameLayout(this.context);
    ViewGroup.LayoutParams layoutParams = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
    rootFrameLayout.setLayoutParams(layoutParams);

    rootFrameLayout.setStatusLayoutManager(this);
  }

  /**
  * 显示loading
  */
  public void showLoading() {
    rootFrameLayout.showLoading();
  }

  /**
  * 显示内容
  */
  public void showContent() {
    rootFrameLayout.showContent();
  }

  /**
  * 显示空数据
  */
  public void showEmptyData(int iconImage, String textTip) {
    rootFrameLayout.showEmptyData(iconImage, textTip);
  }

  /**
  * 显示空数据
  */
  public void showEmptyData() {
    showEmptyData(0, "");
  }

  /**
  * 显示空数据
  */
  public void showLayoutEmptyData(Object... objects) {
    rootFrameLayout.showLayoutEmptyData(objects);
  }

  /**
  * 显示网络异常
  */
  public void showNetWorkError() {
    rootFrameLayout.showNetWorkError();
  }

  /**
  * 显示异常
  */
  public void showError(int iconImage, String textTip) {
    rootFrameLayout.showError(iconImage, textTip);
  }

  /**
  * 显示异常
  */
  public void showError() {
    showError(0, "");
  }

  public void showLayoutError(Object... objects) {
    rootFrameLayout.showLayoutError(objects);
  }

  /**
  * 得到root 布局
  */
  public View getRootLayout() {
    return rootFrameLayout;
  }

  public static final class Builder {

    private Context context;
    private int loadingLayoutResId;
    private int contentLayoutResId;
    private ViewStub netWorkErrorVs;
    private int netWorkErrorRetryViewId;
    private ViewStub emptyDataVs;
    private int emptyDataRetryViewId;
    private ViewStub errorVs;
    private int errorRetryViewId;
    private int retryViewId;
    private int emptyDataIconImageId;
    private int emptyDataTextTipId;
    private int errorIconImageId;
    private int errorTextTipId;
    private VLayout errorLayout;
    private VLayout emptyDataLayout;
    private OnShowHideViewListener onShowHideViewListener;
    private OnRetryListener onRetryListener;

    public Builder(Context context) {
      this.context = context;
    }

    /**
    * 自定义加载布局
    */
    public Builder loadingView(@LayoutRes int loadingLayoutResId) {
      this.loadingLayoutResId = loadingLayoutResId;
      return this;
    }

    /**
    * 自定义网络错误布局
    */
    public Builder netWorkErrorView(@LayoutRes int newWorkErrorId) {
      netWorkErrorVs = new ViewStub(context);
      netWorkErrorVs.setLayoutResource(newWorkErrorId);
      return this;
    }

    /**
    * 自定义加载空数据布局
    */
    public Builder emptyDataView(@LayoutRes int noDataViewId) {
      emptyDataVs = new ViewStub(context);
      emptyDataVs.setLayoutResource(noDataViewId);
      return this;
    }

    /**
    * 自定义加载错误布局
    */
    public Builder errorView(@LayoutRes int errorViewId) {
      errorVs = new ViewStub(context);
      errorVs.setLayoutResource(errorViewId);
      return this;
    }

    /**
    * 自定义加载内容正常布局
    */
    public Builder contentView(@LayoutRes int contentLayoutResId) {
      this.contentLayoutResId = contentLayoutResId;
      return this;
    }

    public Builder errorLayout(VLayout errorLayout) {
      this.errorLayout = errorLayout;
      this.errorVs = errorLayout.getLayoutVs();
      return this;
    }

    public Builder emptyDataLayout(VLayout emptyDataLayout) {
      this.emptyDataLayout = emptyDataLayout;
      this.emptyDataVs = emptyDataLayout.getLayoutVs();
      return this;
    }

    public Builder netWorkErrorRetryViewId(int netWorkErrorRetryViewId) {
      this.netWorkErrorRetryViewId = netWorkErrorRetryViewId;
      return this;
    }

    public Builder emptyDataRetryViewId(int emptyDataRetryViewId) {
      this.emptyDataRetryViewId = emptyDataRetryViewId;
      return this;
    }

    public Builder errorRetryViewId(int errorRetryViewId) {
      this.errorRetryViewId = errorRetryViewId;
      return this;
    }

    public Builder retryViewId(int retryViewId) {
      this.retryViewId = retryViewId;
      return this;
    }

    public Builder emptyDataIconImageId(int emptyDataIconImageId) {
      this.emptyDataIconImageId = emptyDataIconImageId;
      return this;
    }

    public Builder emptyDataTextTipId(int emptyDataTextTipId) {
      this.emptyDataTextTipId = emptyDataTextTipId;
      return this;
    }

    public Builder errorIconImageId(int errorIconImageId) {
      this.errorIconImageId = errorIconImageId;
      return this;
    }

    public Builder errorTextTipId(int errorTextTipId) {
      this.errorTextTipId = errorTextTipId;
      return this;
    }

    public Builder onShowHideViewListener(OnShowHideViewListener onShowHideViewListener) {
      this.onShowHideViewListener = onShowHideViewListener;
      return this;
    }

    public Builder onRetryListener(OnRetryListener onRetryListener) {
      this.onRetryListener = onRetryListener;
      return this;
    }

    public StateLayoutManager build() {
      return new StateLayoutManager(this);
    }
  }

  public static Builder newBuilder(Context context) {
    return new Builder(context);
  }
}

2）.大约5种状态，如何管理这些状态？添加到集合中，Android中选用SparseArray比HashMap更省内存，在某些条件下性能更好，主要是因为它避免了对key的自动装箱（int转为Integer类型），它内部则是通过两个数组来进行数据存储的，一个存储key，另外一个存储value，为了优化性能，它内部对数据还采取了压缩的方式来表示稀疏数组的数据，从而节约内存空间

/**存放布局集合 */
private SparseArray<View> layoutSparseArray = new SparseArray();

/**将布局添加到集合 */
……
private void addLayoutResId(@LayoutRes int layoutResId, int id) {
  View resView = LayoutInflater.from(mStatusLayoutManager.context).inflate(layoutResId, null);
  **layoutSparseArray.put(id, resView);**
  addView(resView);
}

3）.当显示某个布局时，调用的方法如下

方法里面通过id判断来执行不同的代码，首先判断ViewStub是否为空，如果为空就代表没有添加这个View就返回false，不为空就加载View并且添加到集合当中，然后调用showHideViewById方法显示隐藏View，retryLoad方法是给重试按钮添加事件

/**
* 显示loading
*/
public void showLoading() {
  if (layoutSparseArray.get(LAYOUT_LOADING_ID) != null)
    **showHideViewById**(LAYOUT_LOADING_ID);
}

/**
* 显示内容
*/
public void showContent() {
  if (layoutSparseArray.get(LAYOUT_CONTENT_ID) != null)
    **showHideViewById**(LAYOUT_CONTENT_ID);
}

/**
* 显示空数据
*/
public void showEmptyData(int iconImage, String textTip) {
  if (**inflateLayout**(LAYOUT_EMPTYDATA_ID)) {
    showHideViewById(LAYOUT_EMPTYDATA_ID);
    emptyDataViewAddData(iconImage, textTip);
  }
}

/**
* 显示网络异常
*/
public void showNetWorkError() {
  if (**inflateLayout**(LAYOUT_NETWORK_ERROR_ID))
    showHideViewById(LAYOUT_NETWORK_ERROR_ID);
}

/**
* 显示异常
*/
public void showError(int iconImage, String textTip) {
  if (**inflateLayout**(LAYOUT_ERROR_ID)) {
    showHideViewById(LAYOUT_ERROR_ID);
    errorViewAddData(iconImage, textTip);
  }
}

//调用inflateLayout方法，方法返回true然后调用showHideViewById方法
private boolean inflateLayout(int id) {
  boolean isShow = true;
  if (layoutSparseArray.get(id) != null) return isShow;
  switch (id) {
    case LAYOUT_NETWORK_ERROR_ID:
      if (mStatusLayoutManager.netWorkErrorVs != null) {
        View view = mStatusLayoutManager.netWorkErrorVs.inflate();
        retryLoad(view, mStatusLayoutManager.netWorkErrorRetryViewId);
        layoutSparseArray.put(id, view);
        isShow = true;
      } else {
        isShow = false;
      }
      break;
    case LAYOUT_ERROR_ID:
      if (mStatusLayoutManager.errorVs != null) {
        View view = mStatusLayoutManager.errorVs.inflate();
        if (mStatusLayoutManager.errorLayout != null) mStatusLayoutManager.errorLayout.setView(view);
        retryLoad(view, mStatusLayoutManager.errorRetryViewId);
        layoutSparseArray.put(id, view);
        isShow = true;
      } else {
        isShow = false;
      }
      break;
    case LAYOUT_EMPTYDATA_ID:
      if (mStatusLayoutManager.emptyDataVs != null) {
        View view = mStatusLayoutManager.emptyDataVs.inflate();
        if (mStatusLayoutManager.emptyDataLayout != null) mStatusLayoutManager.emptyDataLayout.setView(view);
        retryLoad(view, mStatusLayoutManager.emptyDataRetryViewId);
        layoutSparseArray.put(id, view);
        isShow = true;
      } else {
        isShow = false;
      }
      break;
  }
  return isShow;
}

4）.然后在根据id隐藏布局

通过id找到需要显示的View并且显示它，隐藏其他View，如果显示隐藏监听事件不为空，就分别调用它的显示和隐藏方法

/**
* 根据ID显示隐藏布局
* @param id
*/
private void showHideViewById(int id) {
  for (int i = 0; i < layoutSparseArray.size(); i++) {
    int key = layoutSparseArray.keyAt(i);
    View valueView = layoutSparseArray.valueAt(i);
    //显示该view
    if(key == id) {
      valueView.setVisibility(View.VISIBLE);
      if(mStatusLayoutManager.onShowHideViewListener != null) mStatusLayoutManager.onShowHideViewListener.onShowView(valueView, key);
    } else {
      if(valueView.getVisibility() != View.GONE) {
        valueView.setVisibility(View.GONE);
        if(mStatusLayoutManager.onShowHideViewListener != null) mStatusLayoutManager.onShowHideViewListener.onHideView(valueView, key);
      }
    }
  }
}

5）.最后看看重新加载方法

/**
* 重试加载
*/
private void retryLoad(View view, int id) {
  View retryView = view.findViewById(mStatusLayoutManager.retryViewId != 0 ? mStatusLayoutManager.retryViewId : id);
  if (retryView == null || mStatusLayoutManager.onRetryListener == null) return;
  retryView.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
      mStatusLayoutManager.onRetryListener.onRetry();
    }
  });
}

5.使用方法介绍

1）.直接在Activity中添加代码

@Override
protected void initStatusLayout() {
  statusLayoutManager = StateLayoutManager.newBuilder(this)
      .contentView(R.layout.activity_content_data)
      .emptyDataView(R.layout.activity_empty_data)
      .errorView(R.layout.activity_error_data)
      .loadingView(R.layout.activity_loading_data)
      .netWorkErrorView(R.layout.activity_networkerror)
      .onRetryListener(new OnRetryListener() {
        @Override
        public void onRetry() {
          //为重试加载按钮的监听事件
        }
      })
      .onShowHideViewListener(new OnShowHideViewListener() {
        @Override
        public void onShowView(View view, int id) {
          //为状态View显示监听事件
        }

        @Override
        public void onHideView(View view, int id) {
          //为状态View隐藏监听事件
        }
      })
      .build();
}

2）.在父类中重写以下几个方法，子类直接继承就行

//正常展示数据状态
protected void showContent() {
  statusLayoutManager.showContent();
}

//加载数据为空时状态
protected void showEmptyData() {
  statusLayoutManager.showEmptyData();
}

//加载数据错误时状态
protected void showError() {
  statusLayoutManager.showError();
}

//网络错误时状态
protected void showNetWorkError() {
  statusLayoutManager.showNetWorkError();
}

//正在加载中状态
protected void showLoading() {
  statusLayoutManager.showLoading();
}

3）.更加详细的介绍，可以直接参考Demo
https://github.com/yangchong211/YCStateLayout

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。