由于项目需要,最近开始借鉴学习下开源的Android即时通信聊天UI框架,为此结合市面上加上本项目需求列了ChatUI要实现的基本功能与扩展功能。
为了实现业务与UI分离,分析融云UI部分代码,下面主要从IMKit下的ConversationFragment,RongExtension,plugin包下类实现插件化;
简单点来讲,上面是一个LIstView,下面是个带有EditText扩展横向布局器--输入聊天框,如下图所示,相对布局中存在两个id为:rc_layout_msg_list与rc_extension的布局; 本文的重点是分析输入聊天框以及扩展功能插件的代码,涉及到IMLib的代码会跳过,更好的分析UI是如何实现的;
直观的来看布局,它有4个部分组成,语音按钮,输入框,表情按钮,扩展按钮;
四个控件点击事件需要控制其他控件的显示与隐藏,简化图如下:
   public View inflate(XmlPullParser parser, @Nullable ViewGroup root) {
        return inflate(parser, root, root != null);
    }
   public View inflate(@LayoutRes int resource, @Nullable ViewGroup root, boolean attachToRoot) {
        final Resources res = getContext().getResources();
        if (DEBUG) {
            Log.d(TAG, "INFLATING from resource: \"" + res.getResourceName(resource) + "\" ("
                    + Integer.toHexString(resource) + ")");
        }
        final XmlResourceParser parser = res.getLayout(resource);
        try {
            return inflate(parser, root, attachToRoot);//核心方法
        } finally {
            parser.close();
        }
    } public View inflate(XmlPullParser parser, @Nullable ViewGroup root, boolean attachToRoot) {
        synchronized (mConstructorArgs) {
            Trace.traceBegin(Trace.TRACE_TAG_VIEW, "inflate");
            final Context inflaterContext = mContext;
            final AttributeSet attrs = Xml.asAttributeSet(parser);
            Context lastContext = (Context) mConstructorArgs[0];
            mConstructorArgs[0] = inflaterContext;
            View result = root;
            try {
                // Look for the root node.
                int type;
                while ((type = parser.next()) != XmlPullParser.START_TAG &&
                        type != XmlPullParser.END_DOCUMENT) {
                    // Empty
                }
                if (type != XmlPullParser.START_TAG) {
                    throw new InflateException(parser.getPositionDescription()
                            + ": No start tag found!");
                }
                final String name = parser.getName();
                
                if (TAG_MERGE.equals(name)) {
                    if (root == null || !attachToRoot) {
                        throw new InflateException("<merge /> can be used only with a valid "
                                + "ViewGroup root and attachToRoot=true");
                    }
                    rInflate(parser, root, inflaterContext, attrs, false);
                } else {
                    // 关注下面一部分代码
                    // Temp is the root view that was found in the xml
                    final View temp = createViewFromTag(root, name, inflaterContext, attrs);
                    ViewGroup.LayoutParams params = null;
                    if (root != null) {
                        if (DEBUG) {
                            System.out.println("Creating params from root: " +
                                    root);
                        }
                        // Create layout params that match root, if supplied
                        params = root.generateLayoutParams(attrs);
                        if (!attachToRoot) {
                            // Set the layout params for temp if we are not
                            // attaching. (If we are, we use addView, below)
                            temp.setLayoutParams(params);
                        }
                    }
                  
                    // Inflate all children under temp against its context.
                    rInflateChildren(parser, temp, attrs, true);
                    // We are supposed to attach all the views we found (int temp)
                    // to root. Do that now. xml布局添加到root返回xml布局
                    if (root != null && attachToRoot) {
                        root.addView(temp, params);
                    }
                    // Decide whether to return the root that was passed in or the
                    // top view found in xml.result 赋值为xml布局对象
                    if (root == null || !attachToRoot) {
                        result = temp;
                    }
                }
            } catch (XmlPullParserException e) {
                InflateException ex = new InflateException(e.getMessage());
                ex.initCause(e);
                throw ex;
            } catch (Exception e) {
                InflateException ex = new InflateException(
                        parser.getPositionDescription()
                                + ": " + e.getMessage());
                ex.initCause(e);
                throw ex;
            } finally {
                // Don't retain static reference on context.
                mConstructorArgs[0] = lastContext;
                mConstructorArgs[1] = null;
            }
            Trace.traceEnd(Trace.TRACE_TAG_VIEW);
            return result;
        }
    }inflate(R.layout.rc_ext_voice_input, this.mContainerLayout, true),根据上面可知这个效果是把录取语音按钮加到mContainerLayout中并返回mContainerLayout对象,那么现在存在两个孩子View,因为Framelayout布局中存在多个子控件会覆盖,因此这个先隐藏起来
    this.mExtensionBar = (ViewGroup)LayoutInflater.from(this.getContext()).inflate(R.layout.rc_ext_extension_bar, (ViewGroup)null);
    this.mMainBar = (LinearLayout)this.mExtensionBar.findViewById(R.id.ext_main_bar);
    this.mSwitchLayout = (ViewGroup)this.mExtensionBar.findViewById(R.id.rc_switch_layout);
    this.mContainerLayout = (ViewGroup)this.mExtensionBar.findViewById(R.id.rc_container_layout);
    this.mPluginLayout = (ViewGroup)this.mExtensionBar.findViewById(R.id.rc_plugin_layout);
    this.mEditTextLayout = LayoutInflater.from(this.getContext()).inflate(R.layout.rc_ext_input_edit_text, (ViewGroup)null);
    this.mEditTextLayout.setVisibility(VISIBLE);
    this.mContainerLayout.addView(this.mEditTextLayout);
    LayoutInflater.from(this.getContext()).inflate(R.layout.rc_ext_voice_input, this.mContainerLayout, true);
    this.mVoiceInputToggle = this.mContainerLayout.findViewById(R.id.rc_audio_input_toggle);
    this.mVoiceInputToggle.setVisibility(GONE);
    //省略若干代码
    this.addView(this.mExtensionBar);下面是rc_ext_extension_bar布局代码
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="48dp">
<LinearLayout
    android:id="@+id/ext_main_bar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_centerVertical="true"
    android:gravity="center_vertical"
    android:orientation="horizontal"
    android:paddingLeft="6dp"
    android:paddingRight="6dp">
    <!-- “语音” “公众号菜单” 布局-->
    <LinearLayout
        android:id="@+id/rc_switch_layout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <ImageView
            android:id="@+id/rc_switch_to_menu"
            android:layout_width="41dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:layout_marginRight="6dp"
            android:scaleType="center"
            android:src="@drawable/rc_menu_text_selector"
            android:visibility="gone"/>
        <View
            android:id="@+id/rc_switch_divider"
            android:layout_width="1px"
            android:layout_height="48dp"
            android:background="@color/rc_divider_line"
            android:visibility="gone"/>
        <ImageView
            android:id="@+id/rc_voice_toggle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:layout_marginLeft="6dp"
            android:layout_marginRight="6dp"
            android:src="@drawable/rc_voice_toggle_selector"/>
    </LinearLayout>
    <!-- 文本,表情输入容器,通过控制“语音”,容器中填充不同的内容 -->
    <FrameLayout
        android:id="@+id/rc_container_layout"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:paddingTop="3dp"
        android:paddingBottom="3dp"
        android:gravity="center_vertical"/>
    <!-- 扩展栏 “+号” 布局-->
    <LinearLayout
        android:id="@+id/rc_plugin_layout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="6dp"
        android:layout_marginRight="6dp"
        android:orientation="horizontal">
        <ImageView
            android:id="@+id/rc_plugin_toggle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/rc_plugin_toggle_selector"/>
    </LinearLayout>
</LinearLayout>
<!-- 底部分割线 -->
<View
    android:layout_width="match_parent"
    android:layout_height="2px"
    android:layout_alignParentTop="true"
    android:background="@color/rc_divider_color"/>
</RelativeLayout>   //文本框输入之前
   public void beforeTextChanged(CharSequence s, int start,
                                  int count, int after);
    //文本框正在输入
    public void onTextChanged(CharSequence s, int start, int before, int count);
    //文本框输入后
    public void afterTextChanged(Editable s);public interface IExtensionClickListener extends TextWatcher {
    //发送按钮回调事件
    void onSendToggleClick(View var1, String var2);
    //发送图片回调事件
    void onImageResult(List<Uri> var1, boolean var2);
    //发送地理位置回调事件
    void onLocationResult(double var1, double var3, String var5, Uri var6);
    //语音按钮切换回调事件
    void onSwitchToggleClick(View var1, ViewGroup var2);
    //声音按钮触摸回调事件
    void onVoiceInputToggleTouch(View var1, MotionEvent var2);
    //表情按钮点击回调事件
    void onEmoticonToggleClick(View var1, ViewGroup var2);
    //‘+’按钮点击回调事件
    void onPluginToggleClick(View var1, ViewGroup var2);
    void onMenuClick(int var1, int var2);
    //文本框点击回调事件
    void onEditTextClick(EditText var1);
    //回调setOnKeyListener事件
    boolean onKey(View var1, int var2, KeyEvent var3);
    
    void onExtensionCollapsed();
    void onExtensionExpanded(int var1);
    //插件Item点击回调事件
    void onPluginClicked(IPluginModule var1, int var2);
}