《Android进阶》之第六篇 Fragment 的使用2

最近通过学习，对fragment的使用有了新的认识。

一开始接触android的时候，很是受不了这个fragment，总感觉它把一个简单的事情搞复杂啦，所以每次新建工程的时候总是固执的选择empty Activity

但是后来发现这样写出来的代码移植的时候总是要该来该去，现在开始偏爱带fragment的工程向导

向导默认生成一个JAVA文件，和两个布局文件

MainActivity.JAVA

package com.example.tesf;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends Activity {

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

if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}

/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {

public PlaceholderFragment() {
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}

}

布局文件：activity_main.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.tesf.MainActivity"
tools:ignore="MergeRootFrame" />

另外一个布局文件：fragment_main.xml 这个布局文件就可以自己发挥啦

下面演示一个登录注册的功能：

package com.example.tesf;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.ViewFlipper;

public class RegiserLogin extends Fragment{

private ImageButton ib_back;
private ImageButton ib_menu;
private TextView regster_text;//
private TextView ivTitleName;
private TextView ivTextViewRigh;
private ViewFlipper vf;
private Button confirm_button;
private Button load_btn;
private EditText login_number;
private EditText login_passward;
private EditText register_number;
private EditText register_passward;
private EditText register_code;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
initView(rootView);
return rootView;
}
private void initView(View view){
vf = (ViewFlipper) view.findViewById(R.id.mainFlipper);
ib_menu = (ImageButton) view.findViewById(R.id.ivTitleBtnLeft2);
ib_back = (ImageButton) view.findViewById(R.id.ivTitleBtnLeft1);

regster_text = (TextView) view.findViewById(R.id.regster_text);
ivTitleName = (TextView) view.findViewById(R.id.ivTitleName);

confirm_button = (Button) view.findViewById(R.id.confirm_button);
load_btn = (Button) view.findViewById(R.id.loadBtn);

login_number = (EditText) view.findViewById(R.id.login_number);
login_passward = (EditText) view.findViewById(R.id.login_passward);
register_number = (EditText) view.findViewById(R.id.register_number);
register_passward = (EditText) view.findViewById(R.id.register_passward);
register_code = (EditText) view.findViewById(R.id.register_code);

ib_back.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
//                finish();
}
});

regster_text.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
ib_menu.setVisibility(View.VISIBLE);
ivTitleName.setText("注册新账号");
vf.showNext();
ib_back.setVisibility(View.GONE);
}
});

ib_menu.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
ib_back.setVisibility(View.VISIBLE);
ivTitleName.setText("登录");
vf.showPrevious();
ib_menu.setVisibility(View.GONE);

}
});

}

}

View Code
实现登录注册功能只需要在向导生成的MainActivity里稍加改动就行

if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new RegiserLogin())
.commit();
}

其实在学习Android的过程中都可以仿照这种模式，在向导生成代码的基础上，自己创建extends Fragment的类，再建一个该类需要用的布局文件。

这样所有的demo都可以在一个工程下完成啦。