圆角Tablayout以及仿微信QQ小红点，数字通知

最近在项目中遇到类似微信或者QQ那样的通知小红点，还要有数字通知，当数字大于99时显示99+。看到网上很多朋友提到用BadgeView（github上有），自己也用了下，发现虽然不错但是还是有点不足。后来又有个功能用到如图所示的Tablayout，



在github上找到了FlycoTabLayout这个开源的项目，不仅满足了市面上大多数Tablayout的UI，还封装了小红点和数字通知的功能，于是把其中具有代表性的几个功能实现在自己的Demo上，最后实现的效果是这个样子的，



废话好像有点多了下面开始进入主题。

FlycoTabLayout这个库里关于Tablayout的设计形式有很多，这里我仅使用了其中的一种SegmentTablayout。SegmentTablayout和Google官方提供的Tablayout不一样，没有定义与ViewPager关联起来的方法。所以我在使用的时候需要给它设置选中监听。

这部分的布局文件很简单：

<com.flyco.tablayout.SegmentTabLayout
android:id="@+id/mtablayout"
android:layout_width="match_parent"
android:layout_height="32dp"
android:layout_gravity="center_horizontal"
android:layout_margin="10dp"
tl:tl_bar_color="#ffffff"
tl:tl_indicator_color="#2C97DE"
tl:tl_indicator_corner_radius="8dp"
tl:tl_tab_padding="20dp"
/>
<android.support.v4.view.ViewPager
android:id="@+id/mviewpager"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>

 

程序部分代码：
private String[] mTitles = {"警告","通知","推荐"};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tabLayout = (SegmentTabLayout) findViewById(R.id.mtablayout);
viewPager = (ViewPager) findViewById(R.id.mviewpager);
fragments.add(new PagerOne());
fragments.add(new PagerTwo());
fragments.add(new PagerThree());
tabLayout.setTabData(mTitles);//给Tablayout设置标题

viewPager.setAdapter(new MyPagerAdpater(getSupportFragmentManager()));
//为tablayout设置选中监听
tabLayout.setOnTabSelectListener(new OnTabSelectListener() {
@Override
public void onTabSelect(int position) {
viewPager.setCurrentItem(position);
}

@Override
public void onTabReselect(int position) {

}
});

//同时，还要给Viewpager设置选中监听，才能使SegmentTablayout和ViewPager双向同步。
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int
positionOffsetPixels) {

}

@Override
public void onPageSelected(int position) {
tabLayout.setCurrentTab(position);
}

@Override
public void onPageScrollStateChanged(int state) {

}
});
至于Adapter的代码就是灰常简单了。
private class MyPagerAdpater extends FragmentPagerAdapter {
public MyPagerAdpater(FragmentManager fm) {
super(fm);
}

@Override
public int getCount() {
return fragments.size();
}

@Override
public CharSequence getPageTitle(int position) {
return mTitles[position];
}

@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
}

这样就形成了文章最开始贴的图片的Tab样式了，并且Viewpager随便滑，Tab随便点。

下面开始说小红点，在FlycoTabLayout中定义了一个小红点的封装类——MsgView。当要添加小红点的时候，我们只需要在布局文件中把它加上就好了，下面先说我在顶部Toolbar上的99+小红点，布局文件代码如下：

<android.support.v7.widget.Toolbar
android:id="@+id/azure_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#0065bd">
<RelativeLayout android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageButton
android:id="@+id/notification"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@android:color/transparent"
android:src="@android:drawable/ic_menu_add"/>
<com.flyco.tablayout.widget.MsgView
android:id="@+id/msgview"
xmlns:mv="http://schemas.android.com/apk/res-auto"
android:layout_toRightOf="@id/notification"
android:gravity="center"
android:textColor="#ffffff"
android:textSize="11.5sp"
android:visibility="gone"
mv:mv_backgroundColor="#FD481F"
mv:mv_isRadiusHalfHeight="true"
mv:mv_strokeColor="#ffffff"
mv:mv_strokeWidth="1dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>

<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:text="Tablayout"
android:textColor="#ffffff"
android:textSize="16sp"/>
</android.support.v7.widget.Toolbar>

MsgView定义了三种红点的显示方式：1.没有数字的，就单纯显示个点。2.数字在1-99的，显示实际数字。3.数字大于99的，显示99+。

我们在Toolbar上的99+，实际上就一行代码的事儿。

{
//添加未读消息,带数字未读红点。其实就是在布局文件中写好了
msgView = (MsgView) findViewById(R.id.msgview);
UnreadMsgUtils.show(msgView,666);
}

Tab上通知的小红点呢，不要我们写布局文件和其他方法，SegmentTablayout都给我们封装好了，我们只需要调用SegmentTablayout.showDot(position)方法就行了。

当然，还没有结束，我底部红点就和这些不一样了，底部我采用的是RadioGroup和RadioButton的方式，如果直接在需要显示红点的地方加上MsgView，会不显示，那怎么办呢？这时候就需要我们自己定义一个RadioGroup，让它继承LinearLayout，这样就可以了。

public class NestRadioGroup extends LinearLayout {
// holds the checked id; the selection is empty by default
private int mCheckedId = -1;
// tracks children radio buttons checked state
private CompoundButton.OnCheckedChangeListener mChildOnCheckedChangeListener;
// when true, mOnCheckedChangeListener discards events
private boolean mProtectFromCheckedChange = false;
private OnCheckedChangeListener mOnCheckedChangeListener;
private PassThroughHierarchyChangeListener mPassThroughListener;

/**
* {@inheritDoc}
*/
public NestRadioGroup(Context context) {
super(context);
init();
}

/**
* {@inheritDoc}
*/
public NestRadioGroup(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}

private void init() {
mCheckedId = View.NO_ID;
setOrientation(HORIZONTAL);
mChildOnCheckedChangeListener = new CheckedStateTracker();
mPassThroughListener = new PassThroughHierarchyChangeListener();
super.setOnHierarchyChangeListener(mPassThroughListener);
}

/**
* {@inheritDoc}
*/
@Override
public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) {
// the user listener is delegated to our pass-through listener
mPassThroughListener.mOnHierarchyChangeListener = listener;
}

/**
* {@inheritDoc}
*/
@Override
protected void onFinishInflate() {
super.onFinishInflate();

// checks the appropriate radio button as requested in the XML file
if (mCheckedId != View.NO_ID) {
mProtectFromCheckedChange = true;
setCheckedStateForView(mCheckedId, true);
mProtectFromCheckedChange = false;
setCheckedId(mCheckedId);
}
}

/** 递归查找具有选中属性的子控件 */
private static CompoundButton findCheckedView(View child) {
if (child instanceof CompoundButton)
return (CompoundButton) child;
if (child instanceof ViewGroup) {
ViewGroup group = (ViewGroup) child;
for (int i = 0, j = group.getChildCount(); i < j; i++) {
CompoundButton check = findCheckedView(group.getChildAt(i));
if (check != null)
return check;
}
}
return null;//没有找到
}

@Override
public void addView(View child, int index, ViewGroup.LayoutParams params) {
final CompoundButton view = findCheckedView(child);
if (view != null) {
if (view.isChecked()) {
mProtectFromCheckedChange = true;
if (mCheckedId != -1) {
setCheckedStateForView(mCheckedId, false);
}
mProtectFromCheckedChange = false;
setCheckedId(view.getId());
}
}
super.addView(child, index, params);
}

/**
* <p>Sets the selection to the radio button whose identifier is passed in
* parameter. Using -1 as the selection identifier clears the selection;
* such an operation is equivalent to invoking {@link #clearCheck()}.</p>
*
* @param id the unique id of the radio button to select in this group
*
* @see #getCheckedRadioButtonId()
* @see #clearCheck()
*/
public void check(int id) {
// don't even bother
if (id != -1 && (id == mCheckedId)) {
return;
}

if (mCheckedId != -1) {
setCheckedStateForView(mCheckedId, false);
}

if (id != -1) {
setCheckedStateForView(id, true);
}

setCheckedId(id);
}

private void setCheckedId(int id) {
mCheckedId = id;
if (mOnCheckedChangeListener != null) {
mOnCheckedChangeListener.onCheckedChanged(this, mCheckedId);
}
}

private void setCheckedStateForView(int viewId, boolean checked) {
View checkedView = findViewById(viewId);
if (checkedView != null && checkedView instanceof CompoundButton) {
((CompoundButton) checkedView).setChecked(checked);
}
}

/**
* <p>Returns the identifier of the selected radio button in this group.
* Upon empty selection, the returned value is -1.</p>
*
* @return the unique id of the selected radio button in this group
*
* @see #check(int)
* @see #clearCheck()
*
* @attr ref android.R.styleable#NestRadioGroup_checkedButton
*/
public int getCheckedRadioButtonId() {
return mCheckedId;
}

/**
* <p>Clears the selection. When the selection is cleared, no radio button
* in this group is selected and {@link #getCheckedRadioButtonId()} returns
* null.</p>
*
* @see #check(int)
* @see #getCheckedRadioButtonId()
*/
public void clearCheck() {
check(-1);
}

/**
* <p>Register a callback to be invoked when the checked radio button
* changes in this group.</p>
*
* @param listener the callback to call on checked state change
*/
public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {
mOnCheckedChangeListener = listener;
}

/**
* {@inheritDoc}
*/
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new NestRadioGroup.LayoutParams(getContext(), attrs);
}

/**
* {@inheritDoc}
*/
@Override
protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
return p instanceof NestRadioGroup.LayoutParams;
}

@Override
protected LinearLayout.LayoutParams generateDefaultLayoutParams() {
return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
}

/**
* <p>This set of layout parameters defaults the width and the height of
* the children to {@link #WRAP_CONTENT} when they are not specified in the
* XML file. Otherwise, this class ussed the value read from the XML file.</p>
*
* <p>See
* {@link android.R.styleable#LinearLayout_Layout LinearLayout Attributes}
* for a list of all child view attributes that this class supports.</p>
*
*/
public static class LayoutParams extends LinearLayout.LayoutParams {
/**
* {@inheritDoc}
*/
public LayoutParams(Context c, AttributeSet attrs) {
super(c, attrs);
}

/**
* {@inheritDoc}
*/
public LayoutParams(int w, int h) {
super(w, h);
}

/**
* {@inheritDoc}
*/
public LayoutParams(int w, int h, float initWeight) {
super(w, h, initWeight);
}

/**
* {@inheritDoc}
*/
public LayoutParams(ViewGroup.LayoutParams p) {
super(p);
}

/**
* {@inheritDoc}
*/
public LayoutParams(MarginLayoutParams source) {
super(source);
}

/**
* <p>Fixes the child's width to
* {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} and the child's
* height to  {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT}
* when not specified in the XML file.</p>
*
* @param a the styled attributes set
* @param widthAttr the width attribute to fetch
* @param heightAttr the height attribute to fetch
*/
@Override
protected void setBaseAttributes(TypedArray a, int widthAttr, int heightAttr) {

if (a.hasValue(widthAttr)) {
width = a.getLayoutDimension(widthAttr, "layout_width");
} else {
width = WRAP_CONTENT;
}

if (a.hasValue(heightAttr)) {
height = a.getLayoutDimension(heightAttr, "layout_height");
} else {
height = WRAP_CONTENT;
}
}
}

/**
* <p>Interface definition for a callback to be invoked when the checked
* radio button changed in this group.</p>
*/
public interface OnCheckedChangeListener {
/**
* <p>Called when the checked radio button has changed. When the
* selection is cleared, checkedId is -1.</p>
*
* @param group the group in which the checked radio button has changed
* @param checkedId the unique identifier of the newly checked radio button
*/
public void onCheckedChanged(NestRadioGroup group, int checkedId);
}

private class CheckedStateTracker implements CompoundButton.OnCheckedChangeListener {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// prevents from infinite recursion
if (mProtectFromCheckedChange) {
return;
}

mProtectFromCheckedChange = true;
if (mCheckedId != -1) {
setCheckedStateForView(mCheckedId, false);
}
mProtectFromCheckedChange = false;

int id = buttonView.getId();
setCheckedId(id);
}
}

/**
* <p>A pass-through listener acts upon the events and dispatches them
* to another listener. This allows the table layout to set its own internal
* hierarchy change listener without preventing the user to setup his.</p>
*/
private class PassThroughHierarchyChangeListener implements ViewGroup.OnHierarchyChangeListener {
private ViewGroup.OnHierarchyChangeListener mOnHierarchyChangeListener;

/**
* {@inheritDoc}
*/
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
public void onChildViewAdded(View parent, View child) {
if (parent == NestRadioGroup.this) {
CompoundButton view = findCheckedView(child);//查找子控件
if (view != null) {
int id = view.getId();
// generates an id if it's missing
if (id == View.NO_ID && Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
id = View.generateViewId();
view.setId(id);
}
view.setOnCheckedChangeListener(mChildOnCheckedChangeListener);
}
}

if (mOnHierarchyChangeListener != null) {
mOnHierarchyChangeListener.onChildViewAdded(parent, child);
}
}

/**
* {@inheritDoc}
*/
public void onChildViewRemoved(View parent, View child) {
if (parent == NestRadioGroup.this) {
CompoundButton view = findCheckedView(child);//查找子控件
if (view != null) {
view.setOnCheckedChangeListener(null);
}
}

if (mOnHierarchyChangeListener != null) {
mOnHierarchyChangeListener.onChildViewRemoved(parent, child);
}
}
}
}

这时候我们在布局文件中把MsgView加上就可以了。为了不使文章过长，就只粘含有MagView的RadioButton了。

<com.example.v_lzhiy.tablayout.view.NestRadioGroup
android:id="@+id/radioGroup_bottom"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#f9f9f9"
android:gravity="center_horizontal"
android:orientation="horizontal"
android:padding="5dp"
>
<RelativeLayout android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="wrap_content">
<RadioButton
android:id="@+id/rb_azure"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:background="@android:color/transparent"
android:button="@android:color/transparent"
android:drawableTop="@drawable/rb_me_selector"
android:textSize="18sp"
android:textColor="@drawable/bottom_radiobutton_selector"
android:drawablePadding="1dp"
android:gravity="center"
android:text="Home"/>
<com.flyco.tablayout.widget.MsgView
android:id="@+id/msgview_azure"
xmlns:mv="http://schemas.android.com/apk/res-auto"
android:layout_toRightOf="@id/rb_azure"
android:gravity="center"
android:textColor="#ffffff"
android:visibility="visible"
mv:mv_backgroundColor="#FD481F"
mv:mv_isRadiusHalfHeight="true"
mv:mv_strokeColor="#ffffff"
mv:mv_strokeWidth="1dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>

这时候我们再调用UnreadMsgUtils.show(msgView,0);就可以了。但是会发现，这个红点有点小啊，怎么把它变大呢？ 虽然UnreadMsgUtils有提供setSize方法，但是用起来好像没卵用，为什么呢？看看源码就知道了。所以要改变红点的大小需要我们自己写show方法，其实也很简单，只需要把show方法中控制红点宽高的属性调整下就好。我是这样调整的：

radioGroup = (NestRadioGroup) findViewById(R.id.radioGroup_bottom);
msgView_bottom = (MsgView) findViewById(R.id.msgview_azure);
RelativeLayout.LayoutParams lp = (RelativeLayout.LayoutParams) msgView_bottom.getLayoutParams();
DisplayMetrics dm = msgView_bottom.getResources().getDisplayMetrics();
msgView_bottom.setVisibility(View.VISIBLE);
msgView_bottom.setStrokeWidth(0);
msgView_bottom.setText("");

lp.width = (int) (10 * dm.density);//这里从6变10
lp.height = (int) (10 * dm.density);//这里从6变10
msgView_bottom.setLayoutParams(lp);

就这样了，感谢FlycoTabLayout开源项目（github地址：https://github.com/H07000223/FlycoTabLayout）和农民伯伯的支持内部嵌套布局的RadioGroup。（农民伯伯： http://over140.cnblogs.com）
第一次写博客，如果有好的见解的话多多交流，欢迎提建议，O(∩_∩)O谢谢！