如何优化臃肿的fragment
来源:互联网 发布:js获取本机ip地址 编辑:程序博客网 时间:2024/04/28 21:28
正文
一、应用场景
1、不使用ViewPager
2、不能用replace来切换Fragment,会导致Fragment释放(调用onDestroyView)
二、实现
1、xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1.0" >
</FrameLayout>
<RadioGroup
android:id="@+id/main_radio"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:gravity="bottom"
android:layout_marginBottom="-6dp"
android:orientation="horizontal" >
<RadioButton
android:id="@+id/radio_button0"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_1" />
<RadioButton
android:id="@+id/radio_button1"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_2" />
<RadioButton
android:id="@+id/radio_button2"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_3" />
<RadioButton
android:id="@+id/radio_button3"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_4" />
<RadioButton
android:id="@+id/radio_button4"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_5" />
</RadioGroup>
</LinearLayout>
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<FrameLayout
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="1.0" >
</FrameLayout>
<RadioGroup
android:id="@+id/main_radio"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:gravity="bottom"
android:layout_marginBottom="-6dp"
android:orientation="horizontal" >
<RadioButton
android:id="@+id/radio_button0"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_1" />
<RadioButton
android:id="@+id/radio_button1"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_2" />
<RadioButton
android:id="@+id/radio_button2"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_3" />
<RadioButton
android:id="@+id/radio_button3"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_4" />
<RadioButton
android:id="@+id/radio_button4"
style="@style/main_tab_bottom"
android:drawableTop="@drawable/bottom_5" />
</RadioGroup>
</LinearLayout>
代码说明:
非常常见的底部放5个RadioButton,点击切换不同的Fragment。
2、Activity
为RadioButton设置setOnCheckedChangeListener事件,其他代码:
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
Fragment fragment = (Fragment) mFragmentPagerAdapter.instantiateItem(mContainer, buttonView.getId());
mFragmentPagerAdapter.setPrimaryItem(mContainer, 0, fragment);
mFragmentPagerAdapter.finishUpdate(mContainer);
}
}
private FragmentPagerAdapter mFragmentPagerAdapter = new FragmentPagerAdapter(getSupportFragmentManager()) {
@Override
public Fragment getItem(int position) {
switch (position) {
case R.id.radio_button1:
return new Fragment1();
case R.id.radio_button2:
return new Fragment2();
case R.id.radio_button3:
return new Fragment3();
case R.id.radio_button4:
return new Fragment4();
case R.id.radio_button0:
default:
return new Fragment0();
}
}
@Override
public int getCount() {
return 5;
}
};
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
Fragment fragment = (Fragment) mFragmentPagerAdapter.instantiateItem(mContainer, buttonView.getId());
mFragmentPagerAdapter.setPrimaryItem(mContainer, 0, fragment);
mFragmentPagerAdapter.finishUpdate(mContainer);
}
}
private FragmentPagerAdapter mFragmentPagerAdapter = new FragmentPagerAdapter(getSupportFragmentManager()) {
@Override
public Fragment getItem(int position) {
switch (position) {
case R.id.radio_button1:
return new Fragment1();
case R.id.radio_button2:
return new Fragment2();
case R.id.radio_button3:
return new Fragment3();
case R.id.radio_button4:
return new Fragment4();
case R.id.radio_button0:
default:
return new Fragment0();
}
}
@Override
public int getCount() {
return 5;
}
};
代码说明:
instantiateItem从FragmentManager中查找Fragment,找不到就getItem新建一个,setPrimaryItem设置隐藏和显示,最后finishUpdate提交事务。
mContainer就是xml中的FrameLayout。
三、FragmentPagerAdapter核心代码
@Override
public Object instantiateItem(ViewGroup container, int position) {
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
final long itemId = getItemId(position);
// Do we already have this fragment?
String name = makeFragmentName(container.getId(), itemId);
Fragment fragment = mFragmentManager.findFragmentByTag(name);
if (fragment != null) {
if (DEBUG) Log.v(TAG, "Attaching item #" + itemId + ": f=" + fragment);
mCurTransaction.attach(fragment);
} else {
fragment = getItem(position);
if (DEBUG) Log.v(TAG, "Adding item #" + itemId + ": f=" + fragment);
mCurTransaction.add(container.getId(), fragment,
makeFragmentName(container.getId(), itemId));
}
if (fragment != mCurrentPrimaryItem) {
fragment.setMenuVisibility(false);
fragment.setUserVisibleHint(false);
}
return fragment;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
if (DEBUG) Log.v(TAG, "Detaching item #" + getItemId(position) + ": f=" + object
+ " v=" + ((Fragment)object).getView());
mCurTransaction.detach((Fragment)object);
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
Fragment fragment = (Fragment)object;
if (fragment != mCurrentPrimaryItem) {
if (mCurrentPrimaryItem != null) {
mCurrentPrimaryItem.setMenuVisibility(false);
mCurrentPrimaryItem.setUserVisibleHint(false);
}
if (fragment != null) {
fragment.setMenuVisibility(true);
fragment.setUserVisibleHint(true);
}
mCurrentPrimaryItem = fragment;
}
}
@Override
public void finishUpdate(ViewGroup container) {
if (mCurTransaction != null) {
mCurTransaction.commitAllowingStateLoss();
mCurTransaction = null;
mFragmentManager.executePendingTransactions();
}
}
public Object instantiateItem(ViewGroup container, int position) {
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
final long itemId = getItemId(position);
// Do we already have this fragment?
String name = makeFragmentName(container.getId(), itemId);
Fragment fragment = mFragmentManager.findFragmentByTag(name);
if (fragment != null) {
if (DEBUG) Log.v(TAG, "Attaching item #" + itemId + ": f=" + fragment);
mCurTransaction.attach(fragment);
} else {
fragment = getItem(position);
if (DEBUG) Log.v(TAG, "Adding item #" + itemId + ": f=" + fragment);
mCurTransaction.add(container.getId(), fragment,
makeFragmentName(container.getId(), itemId));
}
if (fragment != mCurrentPrimaryItem) {
fragment.setMenuVisibility(false);
fragment.setUserVisibleHint(false);
}
return fragment;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
if (DEBUG) Log.v(TAG, "Detaching item #" + getItemId(position) + ": f=" + object
+ " v=" + ((Fragment)object).getView());
mCurTransaction.detach((Fragment)object);
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
Fragment fragment = (Fragment)object;
if (fragment != mCurrentPrimaryItem) {
if (mCurrentPrimaryItem != null) {
mCurrentPrimaryItem.setMenuVisibility(false);
mCurrentPrimaryItem.setUserVisibleHint(false);
}
if (fragment != null) {
fragment.setMenuVisibility(true);
fragment.setUserVisibleHint(true);
}
mCurrentPrimaryItem = fragment;
}
}
@Override
public void finishUpdate(ViewGroup container) {
if (mCurTransaction != null) {
mCurTransaction.commitAllowingStateLoss();
mCurTransaction = null;
mFragmentManager.executePendingTransactions();
}
}
FragmentPagerAdapter是support包自带的类。
四、注意
之前自己模拟ViewPager用attach、setMenuVisibility、setUserVisibleHint来控制Fragment的显示隐藏,经常会出现Fragment重叠现象,非常头疼,换了这个之后目前没有发现重叠现象。
五、文章后期维护
2013-12-01 上传示例代码:http://files.cnblogs.com/over140/SampleFragmentSwitch.zip
@Override
public void setMenuVisibility(boolean menuVisible) {
super.setMenuVisibility(menuVisible);
if (this.getView() != null)
this.getView().setVisibility(menuVisible ? View.VISIBLE : View.GONE);
}
public void setMenuVisibility(boolean menuVisible) {
super.setMenuVisibility(menuVisible);
if (this.getView() != null)
this.getView().setVisibility(menuVisible ? View.VISIBLE : View.GONE);
}
重新做例子时发现自己也出不来效果了,后来发现少了这段代码。
结束
需要多看看源码,才能很好的解决问题。
0 0
- 如何优化臃肿的fragment
- 臃肿的代码
- VS的臃肿
- Fragment的代码优化
- Fragment的优化1
- fragment+viewpager的优化
- 微软的软件就是臃肿
- 软件太臃肿了,如何解决?
- Fragment代码优化的savedInstance
- 对Fragment切换的优化
- 关于fragment+viewpager的优化
- 苛评VCL: 臃肿的Windows控件
- C#变得越来越臃肿是不可避免的
- 苛评VCL: 臃肿的Windows控件
- 苛评VCL: 臃肿的Windows控件
- 臃肿的C++ - 浅谈过度包装
- 怎么样减少模板特化的代码臃肿
- 利用Eclipse处理臃肿代码的方法
- Java CSV读--Read And Parse CSV File In Java
- clEnqueueNDRangeKernel参数说明
- CentOS升级Python到2.7
- Robbe-1.6.0 发布 - PHP开源中文分词扩展, GBK支持
- 关于框架是否要兼容MYSQL,SQL Server,Oracle
- 如何优化臃肿的fragment
- 怎么获得windows版Redis数据库
- Linux 下将sd格式化成ext2并挂载
- Apache 配置虚拟主机三种方式
- latch: library cache等待(只存在于9i,10g)
- 计算机科学中最重要的32个算法
- 1.jstl
- 模拟javascript函数:
- Linux 配置支持高并发TCP连接(socket最大连接数)