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

时间:2024-06-24 20:35:20

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

  1. Fragment是通过调用getActivity()的方法获取Activity的;
  2. 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

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

  1. public int getCount()

  2. public long getItemId(int position)

  3. public Object getItem(int position)

  4. 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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