效果 GIF
简单介绍一下这个控件，像我们在实际的开发过程中，经常性的会遇到这样的场景，比如进入一个页面先出来加载动画，然后请求数据，如果网络异常就显示网络异常的布局，数据异常、数据为空也有相应的布局，以及当我们请求成功完毕数据后，根据返回的数据值去区分不同VIP等级的用户显示不同的页面，这里我放了两张图，我的女神，迪丽热巴和俞飞鸿，就当做我们在业务开发中的 Layout ，把布局全部写在 xml，然后控制显示隐藏就有点不优雅了，基于这个问题，就有了这个控件。
下面是自定义 View 的自定义属性：
<declare-styleable name="EasyStateView">
// 是否使用过渡动画
<attr name="esv_use_anim" format="boolean"/>
// 加载动画 View
<attr name="esv_loadingView" format="reference" />
// 数据异常，加载失败 View
<attr name="esv_errorDataView" format="reference" />
// 网络异常 View
<attr name="esv_errorNetView" format="reference" />
// 空白页面 View
<attr name="esv_emptyView" format="reference" />
// 设置当前显示的 viewState
<attr name="esv_viewState" format="enum">
<enum name="content" value="0" />
<enum name="loading" value="-1" />
<enum name="error_data" value="-2" />
<enum name="error_net" value="-3" />
<enum name="empty" value="-4" />
</attr>
</declare-styleable>
Java代码：
package com.rzj.view;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ObjectAnimator;
import android.app.Activity;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Rect;
import android.support.annotation.IntDef;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.FrameLayout;
import com.rzj.stateview.R;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.ArrayList;
public class EasyStateView extends FrameLayout {
// 内容 View
public static final int VIEW_CONTENT = 0;
// 加载 View
public static final int VIEW_LOADING = -1;
// 数据异常( 数据异常指原本应该是有数据，但是服务器返回了错误的、不符合格式的数据 ) View
public static final int VIEW_ERROR_DATA = -2;
// 网络异常 View
public static final int VIEW_ERROR_NET = -3;
// 数据为空 View
public static final int VIEW_EMPTY = -4;
// View 的 Tag 标签值
private static final int VIEW_TAG = -5;
// 用来存放 View
private ArrayList<View> mViews;
// 是否使用过渡动画
private boolean mUseAnim;
// 是否处于动画中
private boolean isAniming;
// 当前显示的 ViewTag
private int mCurrentState;
private Context mContext;
private StateViewListener mListener;
// content View 是否被添加到队列
private boolean isAddContent;
public interface StateViewListener {
void onStateChanged(int state);
}
public EasyStateView(Context context) {
this(context, null);
}
public EasyStateView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public EasyStateView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context, attrs);
}
private void init(Context context, AttributeSet attrs) {
mContext = context;
TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.EasyStateView);
mCurrentState = typedArray.getInt(R.styleable.EasyStateView_esv_viewState, VIEW_CONTENT);
Log.e("init", getChildCount() + " " + mCurrentState);
mViews = new ArrayList<>();
int emptyResId = typedArray.getResourceId(R.styleable.EasyStateView_esv_emptyView, VIEW_TAG);
if (emptyResId != VIEW_TAG) {
View view = LayoutInflater.from(getContext()).inflate(emptyResId, this, false);
view.setTag(VIEW_EMPTY);
mViews.add(view);
addViewInLayout(view, -1, view.getLayoutParams());
}
int errorDataResId = typedArray.getResourceId(R.styleable.EasyStateView_esv_errorDataView, VIEW_TAG);
if (errorDataResId != VIEW_TAG) {
View view = LayoutInflater.from(getContext()).inflate(errorDataResId, this, false);
view.setTag(VIEW_ERROR_DATA);
mViews.add(view);
addViewInLayout(view, -1, view.getLayoutParams());
}
int errorNetResId = typedArray.getResourceId(R.styleable.EasyStateView_esv_errorNetView, VIEW_TAG);
if (errorNetResId != VIEW_TAG) {
View view = LayoutInflater.from(getContext()).inflate(errorNetResId, this, false);
view.setTag(VIEW_ERROR_NET);
mViews.add(view);
addViewInLayout(view, -1, view.getLayoutParams());
}
int loadingResId = typedArray.getResourceId(R.styleable.EasyStateView_esv_loadingView, VIEW_TAG);
if (loadingResId != VIEW_TAG) {
View view = LayoutInflater.from(getContext()).inflate(loadingResId, this, false);
view.setTag(VIEW_LOADING);
mViews.add(view);
addViewInLayout(view, -1, view.getLayoutParams());
}
mUseAnim = typedArray.getBoolean(R.styleable.EasyStateView_esv_use_anim, true);
typedArray.recycle();
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
for (View view : mViews) {
if ((Integer) view.getTag() != mCurrentState) {
view.setVisibility(GONE);
}
}
}
@Override
public void addView(View child) {
addContentV(child);
super.addView(child);
}
private void addContentV(View child) {
if (isContentView(child)) {
child.setTag(VIEW_CONTENT);
mViews.add(child);
isAddContent = true;
}
}
@Override
public void addView(View child, int index) {
addContentV(child);
super.addView(child, index);
}
@Override
public void addView(View child, int index, ViewGroup.LayoutParams params) {
addContentV(child);
super.addView(child, index, params);
}
@Override
public void addView(View child, ViewGroup.LayoutParams params) {
addContentV(child);
super.addView(child, params);
}
@Override
public void addView(View child, int width, int height) {
addContentV(child);
super.addView(child, width, height);
}
@Override
protected boolean addViewInLayout(View child, int index, ViewGroup.LayoutParams params) {
addContentV(child);
return super.addViewInLayout(child, index, params);
}
@Override
protected boolean addViewInLayout(View child, int index, ViewGroup.LayoutParams params, boolean preventRequestLayout) {
addContentV(child);
return super.addViewInLayout(child, index, params, preventRequestLayout);
}
private boolean isContentView(View child) {
if (!isAddContent && null != child
&& null == child.getTag()) {
return true;
}
return false;
}
/**
* 切换默认状态的 View
*
* @param state
*/
public void setViewState(int state) {
if (state < VIEW_TAG) {
throw new RuntimeException("ViewState 不在目标范围");
}
if (isAniming) {
return;
}
showViewAnim(state);
}
public void setUseAnim(boolean useAnim) {
this.mUseAnim = useAnim;
}
private void showViewAnim(int state) {
View showView = getStateView(state);
if (null == showView || state == mCurrentState) {
return;
}
isAniming = true;
View currentView = getStateView(mCurrentState);
if (mUseAnim) {
showAlpha(state, showView, currentView);
} else {
currentView.setVisibility(GONE);
if(showView.getAlpha() == 0){
showView.setAlpha(1f);
}
showView.setVisibility(VISIBLE);
mCurrentState = state;
isAniming = false;
}
}
private void showAlpha(final int state, final View showView,
final View currentView) {
ObjectAnimator currentAnim = ObjectAnimator.ofFloat(currentView, "alpha", 1, 0);
currentAnim.setDuration(250L);
final ObjectAnimator showAnim = ObjectAnimator.ofFloat(showView, "alpha", 0, 1);
showAnim.setDuration(250L);
showAnim.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
super.onAnimationEnd(animation);
if (null != mListener) {
mListener.onStateChanged(state);
}
isAniming = false;
}
});
currentAnim.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
super.onAnimationEnd(animation);
currentView.setVisibility(GONE);
showView.setVisibility(VISIBLE);
showAnim.start();
mCurrentState = state;
}
});
currentAnim.start();
}
public int getCurrentState() {
return mCurrentState;
}
public View getStateView(int state) {
if (state < VIEW_TAG) {
throw new RuntimeException("ViewState 不在目标范围");
}
for (View view : mViews) {
if ((Integer) view.getTag() == state) {
return view;
}
}
return null;
}
public void addUserView(int state, int layId) {
setUserDefView(state, null, layId);
}
public void addUserView(int state, View view) {
setUserDefView(state, view, -1);
}
private void setUserDefView(int state, View view, int layId) {
if (state <= 0) {
throw new RuntimeException("自定义的 ViewState TAG 必须大于 0");
}
if (null == view && layId != -1) {
view = LayoutInflater.from(mContext).inflate(layId, this, false);
}
view.setTag(state);
view.setVisibility(GONE);
addViewInLayout(view, -1, view.getLayoutParams());
mViews.add(view);
}
}
简单说明一下，继承 FrameLayout 是因为帧布局是效率最高的布局，添加 View 到布局中用的是addViewInLayout，这里解释一下为什么不用addView，因为addView会触发 requestLayout，addViewInLayout会先添加进去，然后再统一触发布局，这个控件的用法非常简单，控件里面已经内置了很多常用的场景类型，你可以通过 addUserView()这个方法来添加你的 View，目前只有一个过渡动画，后续考虑迭代。
项目的 Github 地址 https://github.com/MarkRaoAndroid/EasyStateView
网友评论