组件与组件间的交互机制

1.布局文件

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" ><TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="Data viewer view" android:textSize="10pt" android:textColor="#00FF00" android:gravity="center_horizontal" android:padding="20sp" /> <EditText android:id="@+id/TXT_DATA" android:layout_width="fill_parent" android:layout_height="fill_parent" android:textSize="6pt" android:editable ="false" android:scrollbars="vertical" android:layout_gravity="top" /> </LinearLayout>

 

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" ><TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="Main view" android:textSize="10pt" android:textColor="#00FF00" android:gravity="center_horizontal" android:padding="20sp" /><Button android:id="@+id/BTN_START" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Start another activity" android:layout_gravity="center_horizontal" /> </LinearLayout>

 

2.代码

package foolstudio.demo;import java.util.ArrayList;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.Toast;public class IntentDataTestAct extends Activity implements OnClickListener {public static final int REQ_CODE = 2012;public static final String EXTRAS_KEY = "EXTRAS_DATA";private ArrayList<Kid> mKids = new ArrayList<Kid>();/*Andoid平台禁止访问Activity的构造函数，否则抛出异常public static IntentDataTestAct mInstance = new IntentDataTestAct();private IntentDataTestAct() {}public static IntentDataTestAct getInstance() {return (mInstance);}*/ /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_view); Button btnStart = (Button)findViewById(R.id.BTN_START); btnStart.setOnClickListener(this); }@Overridepublic void onClick(View v) {// TODO Auto-generated method stubswitch(v.getId() ) {case R.id.BTN_START: {doStart();break;}}}//启动新的活动private void doStart() {Intent startNew = new Intent(this, DataViewerAct.class);ArrayList<Kid> kids = initArrayList();startNew.putParcelableArrayListExtra(EXTRAS_KEY, kids);//this.startActivity(startNew);this.startActivityForResult(startNew, REQ_CODE);}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {// TODO Auto-generated method stubif(requestCode == REQ_CODE) {Bundle bundle = data.getExtras();String msg = bundle.getString("Msg");Toast.makeText(this, msg, Toast.LENGTH_LONG).show();}super.onActivityResult(requestCode, resultCode, data);}//初始化列表private ArrayList<Kid> initArrayList() {//ArrayList<Kid> kids = new ArrayList<Kid>();addKid(mKids, "Jim", Kid.SEX_FEMALE, "2007-5-31");addKid(mKids, "Jane", Kid.SEX_MALE, "2007-10-31");addKid(mKids, "Bob", Kid.SEX_FEMALE, "2007-6-1");return mKids;}//获取列表public ArrayList<Kid> getArrayList() {return (mKids);}//添加小孩记录private void addKid(ArrayList<Kid> kids, String name, int sex_flag, String birthday) {Kid kid = new Kid(name, sex_flag, birthday);kids.add(kid);}};

3.意向对象的附加容器

 

package foolstudio.demo;import android.os.Parcel;import android.os.Parcelable;public class Kid implements Parcelable {public static final int SEX_FEMALE = 1;public static final int SEX_MALE = 0;private String name = null;private int sex = 1;private String birthday = null;//必须要有一个名为CREATOR的成员对象，否则无法进行Parcelable对象通信 public static final Parcelable.Creator<Kid> CREATOR = new Parcelable.Creator<Kid>() {public Kid createFromParcel(Parcel in) { return new Kid(in);}public Kid[] newArray(int size) { return new Kid[size];}};public Kid(String _name, int _sex, String _birthday) {this.birthday = _birthday;this.sex = _sex;this.name = _name;}public void setName(String name) {this.name = name;}public String getName() {return name;}public void setBirthday(String birthday) {this.birthday = birthday;}public String getBirthday() {return birthday;}public void setSex(int sex) {this.sex = sex;}public int getSex() {return sex;}public String toString() {StringBuffer sb = new StringBuffer();sb.append("Name: ");sb.append(this.name + "/n");sb.append("Sex: ");sb.append( ((this.sex == 1) ? "Female" : "Male") + "/n");sb.append("Birthday: ");sb.append(this.birthday );return (sb.toString() );}//实现Parcelable接口public Kid(Parcel in) {this.name = in.readString();this.sex = in.readInt();this.birthday = in.readString();}@Overridepublic int describeContents() {// TODO Auto-generated method stubreturn 0;}@Overridepublic void writeToParcel(Parcel dest, int flags) {// TODO Auto-generated method stubdest.writeString(this.name);dest.writeInt(this.sex);dest.writeString(this.birthday);}};

 

4.被调用方Activity接收传递数据

package foolstudio.demo;import java.util.ArrayList;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.widget.EditText;public class DataViewerAct extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.data_viewer_view); EditText txtData = (EditText)findViewById(R.id.TXT_DATA); //获取父Activity所传递的附加数据 Intent intent = this.getIntent(); ArrayList<Kid> kids = intent.getParcelableArrayListExtra(IntentDataTestAct.EXTRAS_KEY); //ArrayList<Kid> kids = IntentDataTestAct.getInstance().getArrayList(); for(int i = 0; i < kids.size(); ++i) { Kid kid = kids.get(i); txtData.append("#" + i + " ========/n"); txtData.append(kid.toString() ); txtData.append("/n"); } //返回结果 Intent result = new Intent(); result.putExtra("Msg", "Get " + kids.size() + " record(s)."); this.setResult(IntentDataTestAct.REQ_CODE, result); }};

5.注册清单

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="foolstudio.demo" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".IntentDataTestAct" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".DataViewerAct"></activity></application> <uses-sdk android:minSdkVersion="3" /></manifest>