Android开发工程师文集-Fragment，适配器，轮播图，ScrollView，Gallery 图片浏览器，Android常用布局样式

达达前端

发布于 2019-07-03 12:19:22

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发布于 2019-07-03 12:19:22

文章被收录于专栏：达达前端

Android开发工程师文集-Fragment，适配器，轮播图，ScrollView，Gallery 图片浏览器，Android常用布局样式

Fragment

FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction beginTransaction = fragmentManager.beginTransaction();

事务

add(),remove(),replace(),commit()

MyFragment2 fragment2=new MyFragment2();
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction beginTransaction = fragmentManager.beginTransaction();
beginTransaction.add(R.id.frame,fragement2);
beginTransaction.commit();

fragment的生命周期

Created

onAttach()->onCreate()->onCreateView()->onActivityCreated()

Started

onStart()

Resumed

onResume()

Paused

onPause()

Stopped

onStop()

Destroyed

onDestroyView()->onDestroy()->onDetach()

//当Fragment被添加到Activity的时候回调这个方法，并且只调用一次
@Override
public void onAttach(Activity activity){
    super.onAttach(activity);
}

//创建Fragment时会回调，只调用一次
@Override
public void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
}

//每次创建回调
@Override
public View onCreateView(## ##){

}

//当Fragment所在的Activity启动完成后调用
@Override
public void onActivityCreated(Bundle savedInstanceState){
    super.onActivityCreated(savedInstanceState);
}

//启动onStart()
@Override
public void onStart(){
    super.onStart();
}

//onResume
@Override
public void onResume(){
    super.onResume();
}

//onPause 暂停
@Override
public void onPause(){
    super.onPause();
}

//onStop 停止
@Override
public void onStop(){
    super.onStop();
}

//last

//onDestroyView
@Override
public void onDestroyView(){
    super.onDestroyView();
}

//销毁

//onDestroy
@Override
public void onDestroy(){
    super.onDestroy();
}

重点删除Fragment //onDetach

@Override
public void onDetach(){
    super.onDetach();
}

启动Fragment

onAttach()->onCreate()->onCreateView()->onActivityCreated()->onStart()->onResume()

暂停Fragment - //暂停和停止的方法

onPause()->onStop()

重新看到Fragment

onStart()->onResume()

Fragment1 -> Fragment2

Fragment1: onPause()->onStop()->onDestroyView->onDestroy()->onDetach()
Fragment2: onAttach()->onCreate()->onCreateView()->onActivityCreated()->onStart()->onResume()

Fragment2回到主界面时

onPause()->onStop()

又重新看见

//Fragment2回到界面 
onStart()->onResume()

Fragment2 退出

onPause()->onStop()->onDestroyView()->onDestroy()->onDetach()

Fragment与Activity

Fragment是通过调用getActivity()的方法获取Activity的；
Activity是通过调用FragmentManager的findFramentById()的，也可以用findFragmentByTag()方法获取Fragment片段的。

重点

public class MyFragment extends Fragment{
    @Override
    public View onCreateView(LayoutInflater inflater,ViewGrop container,Bundle savedInstanceState){
        return super.onCreateView(inflater,container,savedInstanceState);

        //View view = inflater.inflate(R.layout.fragment, container, false);
        //TextView tv = view.findViewById(R.id.textview);
        //return view;
    }
}

一个Activity调用Fragment的界面显示数据内容

String text = editext.getText().toString();
MyFragment fragment = new MyFragment();
Bundle bundle = new Bundle();
bundle.putString("name",text);
fragment.setArguments(bundle);
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction beginTransaction = fragmentManager.beginTransaction();

//beginTransaction.add(containerViewId,fragment,tag)
beginTransaction.add(R.id.layout.textview,fragment,"fragment");
beginTransaction.commit();

在Fragement中设置

public class MyFragment extends Fragment{
    @0verride
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        View view = inflater.infate(R.layout.fragement,container,false);
        TextView tv=view.findViewById(R.id.textview);
        String text = getArguments().get("name")+"";
        tv.setText(text);
    }
}

Fragment

private String name = "v";
public interface Myvoid
{
    public void name(String name);
}

Activity

implements Myvoid

fragment

@Override
public void onAttach(Activity activity){
    myvoid = activity;
    super.onAttach(activity);
}

回到Activity

覆盖方法

另类

xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@android:color/white"
    android:orientation="vertical">
    
</LinearLayout>

Fragment

public class MyinfoFragment extends Fragment implements View.OnClickListener{

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_myinfo, null);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
    }

    @Override
    public void onClick(View v) {

    }
}

MainActivity

public class MainActivity extends FragmentActivity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        setMain();
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
       
    }

    private void setMain() {
        
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        
    }

    private void setSelectStatus(int index) {
        switch (index){
            
        }
    }
    private void initView() {
        
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            
        }
    }
}

继续

FragmentManager fragmentManager = getFragmentManager();
Fragment findFragmentById = fragmentManager.findFragmentById(R.id.fragment);

ViewPager左右滑动

<android.support.v4.view.ViewPager 
 android:id="@+id/viewpager"
 android:...
 android:...>
</android.support.v4.view.ViewPager>

ViewPager是一种容器，可以盛装两种类型的对象：一种是View对象；也可以放置Fragment。

getLayoutInflater().form(this);
getLayoutInflater().form(this).inflate(resource,root);

配置Adapter：

准备数据源 -> 准备适配器 ->加载适配器

List<View> PagerAdapter

ViewPager的声明：<android.support.v4.view.ViewPager> 是为了解决版本兼容性问题

过程

我们创建好布局文件，然后在MainActivity中添加，进行实例

准备数据源

private List<View> viewList;

viewList = new ArrayList<View>();

显示

View view = View.inflate(this, R.layout.view, null);

添加

viewList.add(view);

准备适配器

@Override
public Object instantiateItem(ViewGroup container, int position){

}

搭建构造方法

public MyPagerAdapter(List<View> viewList){
    this.viewList=viewList;
}

container.addview();
return viewList.get(position);

container.removeView(viweList.get(position));

Adapter

创建Adapter

PagerAdapter pagerAdapter = new PagerAdapter(viewList);

setAdapter(pagerAdapter);

对象

PagerTabStrip和PagerTitleStrip

一个View显示ViewPager，然后在ViewPager中添加PagerTabStrip
<android.support.v4.view.ViewPager 
 ...
 <android.support.v4.view.PagerTabStrip 
  ...>
 </android.support.v4.view.PagerTabStrip>
</android.support.v4.view.ViewPager>

然后加入标题，private List<String> titleList;

同理，ViewPager添加题目

titleList = new ArrayList<String>();
titleList.add("第一题")；
titleList.add("第二题")；
titleList.add("第三题")；
titleList.add("第五题");

在加入PagerAdapter中，创建Adapter下创建，MyPagerAdapter.java

MyPagerAdapter.java

public class MyPagerAdapter extends PagerAdapter{
    private List<View> viewList;
    private List<String> titleList;
    public MyPagerAdapter(List<View> viewList, List<String> titleList){
        this.viewList=viewList;
        this.titleList=titleList;
    }
}

加入题目数量第几题显示标题 getPageTitle(),显示所对应的标题

@Override
public CharSequence getPageTitle(int position){
    //return super.getPageTitle(position);
    return titleList.get(position);
}

PagerTabStrip的属性背景

setBackgroundColor(Color.RED); 文本 setTextColor(); 下划线 setDrawFullUnderline(false); 分割线 setTabIndicatorColor();

PagerTitleStrip 与 PagerTabStrip 类似

适配器

FragmentPagerAdapter

import android.os.Bundle;
import android.support.v4.app.Fragment;

public class ExercisesFragment extends Fragment {

    private ListView lvList;//来源fragment
    private ListItemAdapter adapter; //适配器
    private List<> ebl; //列表集合

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment, null);
    }
    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        initData();
        lvList = view.findViewById(R.id.lv_list);
        adapter = new ListItemAdapter(getActivity());
        adapter.setData(ebl);
        lvList.setAdapter(adapter);
    }

    private void initData(){
        ebl = new ArrayList<Bean>();
        for (int i=0;i<10;i++){
            Bean bean = new Bean();
            bean.id=(i+1);
            switch (i){
                case 0:
                    
                case 9:
                    
                default:
                    break;
            }
        }
    }
}

设置MyFragment继承Fragment

public class MyFragment extends Fragment{
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        return inflater.infate(R.layout.view, container, false);
        //return inflater.infate(R.layout.view, null);
    }
}

点击跳转Fragment

public void onClick(View v) {
        switch (v.getId()){
            case R.id.bottom1:
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new CFragment()).commit();
               
                break;
            case R.id.bottom2:
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new EFragment()).commit();
                
                break;
            case R.id.bottom3:
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new MFragment()).commit();
                
                break;
        }
    }

实例

private List<Fragment> fragmentList;

Fragment作为数据源

添加Fragment
fragmentList = new ArrayList<Fragment>();
fragmentList.add(new Fragment());
添加创建的Fragment
//fragmentList.add(new Fragment%());

导入的包

import android.support.v4.app.Fragment;

配置数据适配器

如果用FragmentPagerAdapter，一次性加载同理

public class MyFragment extends FragmentPagerAdapter{
    private List<Fragment> fragmentList;
    private List<String> titleList;
    public MyFragment(FragmentManager fm，List<Fragment> fragmentList，List<String> titleList){
        super(fm)
        this.fragmentList=fragmentList;
        this.titleList=titleList;
    }
}

MainActivity.java

public class MainActivity extends FragmentActivity implements View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    private void setMain() {
       
    }

    private void setSelectStatus(int index) {
        switch (index){
           
        }
    }
    private void initView() {
        
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new CourseFragment()).commit();
            
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new ExercisesFragment()).commit();
            
                //getSupportFragmentManager().beginTransaction().add(R.id.main_body,new MyinfoFragment()).commit();
        }
    }
}

FragmentPagerAdapter adapter=new FragmentPagerAdapter(getSupportFragmentManager());

轮播图

ViewFlipper

自动播放

静态的方法导入：

<ViewFlipper
 android:id="@+id/flipper"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:layout_marginTop="10dp"
 android:flipInterval="4000">
 <ImageView
 android:scaleType="matrix"
 android:id="@+id/ex2"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"/>
 <ImageView
 android:scaleType="matrix"
 android:id="@+id/ex3"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"/>
 <ImageView
 android:scaleType="matrix"
 android:id="@+id/ex4"
 android:android:layout_width="match_parent"
 android:layout_height="wrap_content"/>
</ViewFlipper>

动态导入：

flipper = findViewById(R.id.flipper); flipper.addView(getImageView(R.drawable.picture));

自己定义动态效果，一般用anim的文件夹表示：

然后创建布局界面：创建轮播图

<ViewFlipper 
 android:id="@+id/flipper"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
</ViewFlipper>

MainActivity.java

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

声明变量

private ViewFlipper flipper;

进行初始化

flipper = findViewById(R.id.flipper);

动态导入：addView(getImageView(R.drawable.picture));

轮播图有多张图片，创建数组，分别导入

获取图片

private ImageView getImageView(int imageId){
    ImageView image = new ImageView(this);
    image.setImageResource(imageId);
    return image;
}

for(int i=0; i<imageId.length;i++){
    flipper.addView(getImageView( 数组[i] ));
}

手势滑动的方法

@Override
public boolean onTouchEvent(MotionEvent event){
    return super.onTouchEvent(event);
}

自动播放效果：

flipper.setFlipInterval(3000);
flipper.startFlipping();

ScrollView

HorizontalScrollView,ScrollView

滚动视图

不能滚动，因为布局不是ScrollVeiw，而是<TextView>

tv.setText(getResources().getString(R.string.content));

如果是这样就可以

<ScrollView
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 <TextView
  android:layout_width="match_parent"
  android:layout_height="wrap_content"/>
</ScrollView>

setOnTouchListener的方法

scroll.setOnTouchListener(new OnTouchListener){

}

记得 scrollBy 和 scrollTo 的区别

Gallery 图片浏览器

Gallery像一个走廊，ImageSwitcher像幻灯片

显示图片，就要对图片进行封装，声明数组

布局
<Gallery 
 android:...
 />
 老样子

图片id,private int[] res 定义数组

我们学过的适配器，都是继承BaseAdapter

ArrayAdapter<String> adapter;
SimpleAdapter adapter;

继承BaseAdapter中必须要实现的方法

public int getCount()
public long getItemId(int position)
public Object getItem(int position)
public View gtView(int position, View convertView, ViewGroup parent)

如果自己定义一个适配器，定义后，实现BaseAdapter中的方法，然后创建构造函数

private int[] images;
public ImageAdapter(int []images)
{
    this.images = images;
}

说明

获取视图

private Context context;
public ImageAdapter(int[] images, Context context){
    this.images = images;
    this.context = context;
}

public View gtView(int position, View convertView, ViewGroup parent)

{
    //ImageView image=new ImageView(this);

    ImageView image = new ImageView(context);
    image.setBackgroundResource(数组[position]);
    //设置图片大小
    image.setLayoutParams(new Gallery.LayoutParams(400,300));
    return image;
}

加载适配器 MainActivity.java

声明适配器： private ImageAdapter adapter;

初始化： adapter = new ImageAdapter(数组的变量名，上下文(this));

gallery.setAdapter(adapter);

无限制浏览

return Interger.MAX_VALUE;

监听器

setOnItemSelectedListener(this);

同样<ImageSwitcher>也要布局

声明 private ImageSwitcher is;

进行初始化 is = findViewById(R.id.is);

监听器：gallery.setOnItemSelectedListener(this);

现实的接口：implements OnItemSelectedListener,ViewFactory

public View makeView(){
    
}

is.setFactory(this);

public View makeView(){
    ImageView image = new ImageView(this);

    return image;
}

SeekBar 拖动进度条

setOnSeekBarChangeListener(this);

<SeekBar 
 style="@android:style/Widget.SeekBar"
 />

<selecter xmlns:android="http...."
 <item 
  android:android:state_pressed="true"
  android:state_window_focused="true"
  andeoid:drawable=""/>

Android常用布局样式

线性布局 LinearLayout

相对布局 RelativeLayout

表格布局 TableLayout

可以使用GridView替代

绝对布局 AbsoluteLayout

帧布局(主要布局叠加) FrameLayout

多用LinearLayout和RelativeLayout

少用AbsoluteLayout

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原始发表：2018.05.24 ，如有侵权请联系 cloudcommunity@tencent.com 删除

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